import { ArrowLeft, CheckCircle2, ChevronDown, ChevronUp, ClipboardList, Copy, EyeOff, FolderKanban, Pencil, Plus, RotateCcw, Save, Star, Trash2 } from "lucide-react";
import { FormEvent, useEffect, useMemo, useState } from "react";
import { toast } from "sonner";
import { Alert } from "@/components/ui/alert";
import { Badge } from "@/components/ui/badge";
import { Button } from "@/components/ui/button";
import { Card, CardContent, CardDescription, CardHeader, CardTitle } from "@/components/ui/card";
import { Checkbox } from "@/components/ui/checkbox";
import { Dialog, DialogContent, DialogDescription, DialogHeader, DialogTitle } from "@/components/ui/dialog";
import { Input } from "@/components/ui/input";
import { Textarea } from "@/components/ui/textarea";
import { CopyTicketButton } from "@/components/CopyTicketButton";
import { HelpLink } from "@/components/HelpLink";
import { OrganizationSelect } from "@/components/OrganizationSelect";
import { TodoPanel } from "@/components/TodoPanel";
import {
  createSession,
  deleteProject,
  deleteSession,
  hideProject,
  addFavoriteTicket,
  getDashboardPreference,
  getTicketDetails,
  getTicketPeriod,
  removeFavoriteTicket,
  updateSessionBilling,
  updateSessionDetails,
  updateTicket,
  updateTicketDayBilling,
  updateProject,
  updateProjectStatus
} from "../api";
import { currentDay, currentMonth, formatDate, formatDateTime, formatMinutes, formatTimeRange } from "../format";
import { ticketHasRecurringBilling } from "../recurring-billings";
import type { BillingStatus, PeriodType, ProjectSummary, ProjectTeamspaceEntry, SessionEntry, TicketDetailPeriodType, TicketPeriod, WorkType } from "../types";
import { ZammadPriorityBadge, ZammadStateBadge } from "../zammad-meta";
import { cn } from "@/lib/utils";

type TicketDetailPageProps = {
  periodType: TicketDetailPeriodType;
  period: string;
  ticketId: string;
  onNavigate: (to: string) => void;
  onOpenTicketChange?: (ticket: {
    key: string;
    ticketId: string;
    ticketNumber: string;
    periodType: TicketDetailPeriodType;
    period: string;
    path: string;
    returnPath?: string;
    dirty: boolean;
  }) => void;
  returnPath: string;
};

type TicketSessionFormState = {
  organizationId: string;
  organizationName: string | null;
  projectTeamspaceEntryId: string;
  activity: string;
  workType: WorkType;
  day: string;
  startTime: string;
  endTime: string;
};

type ProjectEditFormState = {
  title: string;
  organizationId: string;
  organizationName: string | null;
  description: string;
  startsOn: string;
  endsOn: string;
  teamspaceEntries: ProjectTeamspaceEntryForm[];
};

type ProjectTeamspaceEntryForm = {
  clientId: string;
  teamspaceProject: string;
  hourBudget: string;
  budgetSyncDisabled: boolean;
  manualConsumption: string;
  isDefault: boolean;
};

function emptyTicketSessionForm(): TicketSessionFormState {
  return {
    organizationId: "",
    organizationName: null,
    projectTeamspaceEntryId: "",
    activity: "",
    workType: "support",
    day: currentDay(),
    startTime: "09:00",
    endTime: "09:30"
  };
}

function projectEntryId() {
  if (typeof crypto !== "undefined" && typeof crypto.randomUUID === "function") {
    return crypto.randomUUID();
  }

  return `entry-${Date.now()}-${Math.random().toString(16).slice(2)}`;
}

function projectTeamspaceEntries(project: ProjectSummary): ProjectTeamspaceEntry[] {
  if (project.teamspace_entries?.length) {
    return project.teamspace_entries;
  }

  return [
    {
      id: `${project.id}-default`,
      teamspace_project: project.teamspace_project,
      is_default: true,
      hour_budget_minutes: project.hour_budget_minutes,
      manual_consumption_minutes: project.manual_consumption_minutes ?? 0,
      teamspace_consumption_minutes: project.teamspace_consumption_minutes ?? 0,
      consumption_minutes: project.consumption_minutes ?? project.teamspace_consumption_minutes ?? 0,
      display_order: 0
    }
  ];
}

function budgetedProjectTeamspaceEntries(project: ProjectSummary) {
  return projectTeamspaceEntries(project).filter((entry) => Number(entry.hour_budget_minutes ?? 0) > 0);
}

function teamspaceEntryOptionLabel(entry: { teamspace_project: string | null; is_default: boolean }) {
  const label = entry.teamspace_project || "Ohne Teamspace-ID";

  return entry.is_default ? `${label} (Standard)` : label;
}

function projectEditForm(project: ProjectSummary): ProjectEditFormState {
  const entries = projectTeamspaceEntries(project).map((entry, index) => ({
    clientId: entry.id || projectEntryId(),
    teamspaceProject: entry.teamspace_project ?? "",
    hourBudget: formatHoursInput(entry.hour_budget_minutes),
    budgetSyncDisabled: entry.budget_sync_disabled ?? false,
    manualConsumption: formatHoursInput(entry.manual_consumption_minutes),
    isDefault: entry.is_default || index === 0
  }));
  const hasDefault = entries.some((entry) => entry.isDefault);

  return {
    title: project.title ?? "",
    organizationId: project.organization_id ?? "",
    organizationName: project.organization_name ?? project.customer_name ?? null,
    description: combinedProjectDescription(project),
    startsOn: project.starts_on ?? "",
    endsOn: project.ends_on ?? "",
    teamspaceEntries: hasDefault ? entries : entries.map((entry, index) => ({ ...entry, isDefault: index === 0 }))
  };
}

function combinedProjectDescription(project: ProjectSummary) {
  return [project.description, project.goals].map((part) => part.trim()).filter(Boolean).join("\n\n");
}

function BillingButtons({
  session,
  disabled,
  loading,
  onChange
}: {
  session: SessionEntry;
  disabled: boolean;
  loading: boolean;
  onChange: (status: BillingStatus) => void;
}) {
  const status = session.billing_status;

  return (
    <div className="grid grid-cols-2 gap-1.5 sm:inline-grid">
      <Button
        type="button"
        size="sm"
        variant={status === "billed" ? "default" : "secondary"}
        disabled={loading || (disabled && status !== "billed")}
        onClick={() => onChange(status === "billed" ? null : "billed")}
        className={cn("h-8", status === "billed" ? "" : "bg-secondary/70")}
      >
        Abgerechnet
      </Button>
      <Button
        type="button"
        size="sm"
        variant={status === "non_billable" ? "default" : "secondary"}
        disabled={loading || (disabled && status !== "non_billable")}
        onClick={() => onChange(status === "non_billable" ? null : "non_billable")}
        className={cn("h-8", status === "non_billable" ? "" : "bg-secondary/70")}
      >
        Nicht abrechenbar
      </Button>
    </div>
  );
}

function sessionDayKey(value: string) {
  const date = new Date(value);
  return `${date.getFullYear()}-${String(date.getMonth() + 1).padStart(2, "0")}-${String(date.getDate()).padStart(2, "0")}`;
}

async function writeTextToClipboard(value: string) {
  if (typeof navigator !== "undefined" && navigator.clipboard?.writeText) {
    await navigator.clipboard.writeText(value);
    return;
  }

  if (typeof document === "undefined") {
    throw new Error("Zwischenablage nicht verfügbar");
  }

  const textarea = document.createElement("textarea");
  textarea.value = value;
  textarea.style.position = "fixed";
  textarea.style.left = "-9999px";
  textarea.setAttribute("readonly", "");
  document.body.appendChild(textarea);
  textarea.focus();
  textarea.select();

  try {
    if (!document.execCommand("copy")) {
      throw new Error("Zwischenablage nicht verfügbar");
    }
  } finally {
    document.body.removeChild(textarea);
  }
}

function teamspacePreparationText(ticket: TicketPeriod["ticket"] | null | undefined, sessions: SessionEntry[]) {
  const ticketNumber = ticket?.ticket_number ?? "Ticket#-";
  const customerName = ticket?.organization_name ?? ticket?.customer_name ?? "-";
  const activities = sessions
    .slice()
    .sort((left, right) => new Date(left.started_at).getTime() - new Date(right.started_at).getTime())
    .map((session) => session.activity.trim())
    .filter(Boolean)
    .join("\n");

  return [`${ticketNumber} - ${customerName}`, "", activities, "", "Tickethandling und Dokumentation"].join("\n");
}

function toDateLocalValue(value: string) {
  const date = new Date(value);
  const offsetMs = date.getTimezoneOffset() * 60_000;
  return new Date(date.getTime() - offsetMs).toISOString().slice(0, 10);
}

function toTimeLocalValue(value: string) {
  const date = new Date(value);
  const offsetMs = date.getTimezoneOffset() * 60_000;
  return new Date(date.getTime() - offsetMs).toISOString().slice(11, 16);
}

function formatHoursInput(minutes?: number | null) {
  if (minutes === null || minutes === undefined) {
    return "";
  }

  return new Intl.NumberFormat("de-DE", { maximumFractionDigits: 2 }).format(minutes / 60);
}

function parseHoursInput(value: string) {
  const trimmed = value.trim();

  if (!trimmed) {
    return null;
  }

  if (/[,.]$/.test(trimmed)) {
    return undefined;
  }

  const hours = Number(trimmed.replace(",", "."));

  if (!Number.isFinite(hours) || hours < 0) {
    return undefined;
  }

  return Math.round(hours * 60);
}

function projectConsumptionBarClass(percent: number) {
  if (percent >= 100) {
    return "bg-blue-500";
  }

  if (percent >= 90) {
    return "bg-red-500";
  }

  return "bg-emerald-500";
}

function projectConsumptionPercent(consumptionMinutes: number, budgetMinutes?: number | null) {
  if (!budgetMinutes || budgetMinutes <= 0) {
    return null;
  }

  return Math.round((consumptionMinutes / budgetMinutes) * 100);
}

function projectRemainingLabel(remainingMinutes: number | null) {
  if (remainingMinutes === null) {
    return "Rest offen";
  }

  if (remainingMinutes < 0) {
    return `Überzogen ${formatMinutes(Math.abs(remainingMinutes))}`;
  }

  return `Rest ${formatMinutes(remainingMinutes)}`;
}

function isPartialHoursInput(value: string) {
  return /^\d*(?:[,.]\d*)?$/.test(value.trim());
}

function normalizeProjectTeamspaceEntryForms(entries: ProjectTeamspaceEntryForm[]) {
  const source = entries.length
    ? entries
    : [
      {
        clientId: projectEntryId(),
        teamspaceProject: "",
        hourBudget: "",
        budgetSyncDisabled: false,
        manualConsumption: "",
        isDefault: true
      }
    ];
  const defaultIndex = Math.max(0, source.findIndex((entry) => entry.isDefault));

  return source.map((entry, index) => ({
    ...entry,
    isDefault: index === defaultIndex
  }));
}

function parseProjectTeamspaceEntryForms(entries: ProjectTeamspaceEntryForm[]) {
  const normalizedEntries = normalizeProjectTeamspaceEntryForms(entries);
  const parsedEntries = normalizedEntries.map((entry) => {
    const hourBudgetMinutes = parseHoursInput(entry.hourBudget);
    const manualConsumptionMinutes = parseHoursInput(entry.manualConsumption);

    if (hourBudgetMinutes === undefined || manualConsumptionMinutes === undefined) {
      return undefined;
    }

    return {
      id: /^\d+$/.test(entry.clientId) ? entry.clientId : null,
      teamspaceProject: entry.teamspaceProject.trim() || null,
      isDefault: entry.isDefault,
      hourBudgetMinutes,
      budgetSyncDisabled: entry.budgetSyncDisabled,
      manualConsumptionMinutes: manualConsumptionMinutes ?? 0
    };
  });

  if (parsedEntries.some((entry) => entry === undefined)) {
    return undefined;
  }

  return parsedEntries as Array<{
    id?: string | null;
    teamspaceProject: string | null;
    isDefault: boolean;
    hourBudgetMinutes: number | null;
    budgetSyncDisabled: boolean;
    manualConsumptionMinutes: number;
  }>;
}

function ProjectTeamspaceEntriesEditor({
  entries,
  onChange
}: {
  entries: ProjectTeamspaceEntryForm[];
  onChange: (entries: ProjectTeamspaceEntryForm[]) => void;
}) {
  const normalizedEntries = normalizeProjectTeamspaceEntryForms(entries);

  function updateEntry(clientId: string, changes: Partial<ProjectTeamspaceEntryForm>) {
    onChange(normalizeProjectTeamspaceEntryForms(normalizedEntries.map((entry) => (entry.clientId === clientId ? { ...entry, ...changes } : entry))));
  }

  function removeEntry(clientId: string) {
    onChange(normalizeProjectTeamspaceEntryForms(normalizedEntries.filter((entry) => entry.clientId !== clientId)));
  }

  return (
    <div className="space-y-2">
      <div className="flex items-center justify-between gap-2">
        <label className="text-sm font-medium">Teamspace-Einträge</label>
        <Button type="button" size="sm" variant="secondary" onClick={() => onChange([...normalizedEntries, { clientId: projectEntryId(), teamspaceProject: "", hourBudget: "", budgetSyncDisabled: false, manualConsumption: "", isDefault: false }])}>
          <Plus className="size-3.5" />
          Eintrag
        </Button>
      </div>
      {normalizedEntries.map((entry, index) => (
        <div key={entry.clientId} className="grid gap-2 rounded-lg border bg-muted/10 p-3 lg:grid-cols-[minmax(180px,1fr)_120px_150px_130px_120px_36px] lg:items-end">
          <div className="space-y-1.5">
            <label className="text-xs font-medium text-muted-foreground" htmlFor={`project-ticket-teamspace-${entry.clientId}`}>
              Teamspace-Projekt {entry.isDefault ? "(Standard)" : ""}
            </label>
            <Input
              id={`project-ticket-teamspace-${entry.clientId}`}
              value={entry.teamspaceProject}
              onChange={(event) => updateEntry(entry.clientId, { teamspaceProject: event.currentTarget.value })}
            />
          </div>
          <div className="space-y-1.5">
            <label className="text-xs font-medium text-muted-foreground" htmlFor={`project-ticket-budget-${entry.clientId}`}>Budget h</label>
            <Input id={`project-ticket-budget-${entry.clientId}`} inputMode="decimal" value={entry.hourBudget} onChange={(event) => updateEntry(entry.clientId, { hourBudget: event.currentTarget.value, budgetSyncDisabled: true })} />
          </div>
          <label className="flex min-h-9 items-center gap-2 rounded-md border bg-background px-3 text-xs">
            <Checkbox checked={entry.budgetSyncDisabled} onCheckedChange={(checked) => updateEntry(entry.clientId, { budgetSyncDisabled: checked === true })} />
            <span>Budget schützen</span>
          </label>
          <div className="space-y-1.5">
            <label className="text-xs font-medium text-muted-foreground" htmlFor={`project-ticket-manual-${entry.clientId}`}>Manueller Verbrauch h</label>
            <Input id={`project-ticket-manual-${entry.clientId}`} inputMode="decimal" value={entry.manualConsumption} onChange={(event) => updateEntry(entry.clientId, { manualConsumption: event.currentTarget.value })} />
          </div>
          <Button
            type="button"
            size="sm"
            variant={entry.isDefault ? "default" : "secondary"}
            onClick={() => onChange(normalizedEntries.map((candidate) => ({ ...candidate, isDefault: candidate.clientId === entry.clientId })))}
          >
            {entry.isDefault ? "Standard" : "Als Standard"}
          </Button>
          <Button type="button" size="icon" variant="ghost" disabled={normalizedEntries.length === 1} onClick={() => removeEntry(entry.clientId)}>
            <Trash2 className="size-4 text-destructive" />
            <span className="sr-only">Teamspace-Eintrag {index + 1} löschen</span>
          </Button>
        </div>
      ))}
      <p className="text-xs text-muted-foreground">Der Standard-Eintrag erhält die gebuchten Teamspace-Tageswerte. Manuelle Stunden zählen nur im Projektverbrauch.</p>
    </div>
  );
}

export function TicketDetailPage({ periodType, period, ticketId, onNavigate, onOpenTicketChange, returnPath }: TicketDetailPageProps) {
  const initialGlobalMonthFilter = periodType === "all" && period !== "all" ? period : currentMonth();
  const [data, setData] = useState<TicketPeriod | null>(null);
  const [loadingId, setLoadingId] = useState<string | null>(null);
  const [deletingId, setDeletingId] = useState<string | null>(null);
  const [savingTicket, setSavingTicket] = useState(false);
  const [savingFavorite, setSavingFavorite] = useState(false);
  const [isFavorite, setIsFavorite] = useState(false);
  const [editTicketNumber, setEditTicketNumber] = useState("");
  const [editTicketTitle, setEditTicketTitle] = useState("");
  const [editOrganizationId, setEditOrganizationId] = useState("");
  const [editOrganizationName, setEditOrganizationName] = useState<string | null>(null);
  const [editWorkType, setEditWorkType] = useState<WorkType>("support");
  const [editingSession, setEditingSession] = useState<SessionEntry | null>(null);
  const [pendingProjectDelete, setPendingProjectDelete] = useState<{ projectId: string } | null>(null);
  const [editSessionOrganizationId, setEditSessionOrganizationId] = useState("");
  const [editSessionOrganizationName, setEditSessionOrganizationName] = useState<string | null>(null);
  const [editSessionActivity, setEditSessionActivity] = useState("");
  const [editSessionWorkType, setEditSessionWorkType] = useState<WorkType>("support");
  const [editSessionProjectTeamspaceEntryId, setEditSessionProjectTeamspaceEntryId] = useState("");
  const [editSessionDay, setEditSessionDay] = useState("");
  const [editSessionStartTime, setEditSessionStartTime] = useState("");
  const [editSessionEndTime, setEditSessionEndTime] = useState("");
  const [savingSessionDetails, setSavingSessionDetails] = useState(false);
  const [dayBillingInputs, setDayBillingInputs] = useState<Record<string, string>>({});
  const [savingDayBillingKey, setSavingDayBillingKey] = useState<string | null>(null);
  const [ticketSession, setTicketSession] = useState<TicketSessionFormState>(() => emptyTicketSessionForm());
  const [savingTicketSession, setSavingTicketSession] = useState(false);
  const [globalMonthFilter, setGlobalMonthFilter] = useState(initialGlobalMonthFilter);
  const [globalStatusFilter, setGlobalStatusFilter] = useState<"all" | "open" | "billed" | "non_billable">("all");
  const [globalSourceFilter, setGlobalSourceFilter] = useState<"all" | "manual" | "recurring">("all");
  const [editingProject, setEditingProject] = useState(false);
  const [savingProject, setSavingProject] = useState(false);
  const [deletingEmptyProject, setDeletingEmptyProject] = useState(false);
  const [savingProjectStatus, setSavingProjectStatus] = useState(false);
  const [projectForm, setProjectForm] = useState<ProjectEditFormState>({
    title: "",
    organizationId: "",
    organizationName: null,
    description: "",
    startsOn: "",
    endsOn: "",
    teamspaceEntries: [
      {
        clientId: projectEntryId(),
        teamspaceProject: "",
        hourBudget: "",
        budgetSyncDisabled: false,
        manualConsumption: "",
        isDefault: true
      }
    ]
  });
  const [todoFilter, setTodoFilter] = useState<"open" | "all" | "done">("open");
  const [expandedSessionIds, setExpandedSessionIds] = useState<string[]>([]);
  const [projectDescriptionExpanded, setProjectDescriptionExpanded] = useState(false);
  const [teamspacePreparation, setTeamspacePreparation] = useState<{ day: string; label: string; text: string } | null>(null);

  async function load() {
    try {
      setData(
        periodType === "all"
          ? await getTicketDetails(ticketId, {
              month: globalMonthFilter,
              status: globalStatusFilter,
              source: globalSourceFilter
            })
          : await getTicketPeriod(periodType, period, ticketId)
      );
    } catch (error) {
      toast.error("Ticket konnte nicht geladen werden", {
        description: error instanceof Error ? error.message : "Unbekannter Fehler"
      });
    }
  }

  useEffect(() => {
    void load();
  }, [periodType, period, ticketId, globalMonthFilter, globalStatusFilter, globalSourceFilter]);

  useEffect(() => {
    if (periodType !== "all") {
      return;
    }

    setGlobalMonthFilter(period !== "all" ? period : currentMonth());
  }, [periodType, period, ticketId]);

  useEffect(() => {
    const nextInputs = Object.fromEntries((data?.dayBillings ?? []).map((billing) => [billing.day, formatHoursInput(billing.billed_minutes)]));
    setDayBillingInputs(nextInputs);
  }, [data?.dayBillings]);

  useEffect(() => {
    if (!data?.ticket) {
      return;
    }

    setEditTicketNumber(data.ticket.ticket_number);
    setEditTicketTitle(data.ticket.title ?? "");
    setEditOrganizationId(data.ticket.organization_id ?? "");
    setEditOrganizationName(data.ticket.organization_name ?? null);
    setEditWorkType(data.ticket.work_type ?? "support");
    const loadedProjectEntries = data.project ? projectTeamspaceEntries(data.project) : [];
    setTicketSession((current) => ({
      ...current,
      organizationId: data.ticket.organization_id ?? current.organizationId,
      organizationName: data.ticket.organization_name ?? current.organizationName,
      projectTeamspaceEntryId: loadedProjectEntries.length === 1 ? loadedProjectEntries[0].id : current.projectTeamspaceEntryId,
      workType: data.ticket.work_type ?? current.workType
    }));
  }, [data?.ticket, data?.project]);

  useEffect(() => {
    setProjectDescriptionExpanded(false);
  }, [data?.project?.id]);

  const ticket = data?.ticket;
  const project = data?.project ?? null;
  const isRecurringBillingTicket = ticketHasRecurringBilling(ticket);
  const projectDescription = project ? combinedProjectDescription(project) : "";
  const projectEntries = useMemo(() => (project ? projectTeamspaceEntries(project) : []), [project]);
  const budgetedProjectEntries = useMemo(() => (project ? budgetedProjectTeamspaceEntries(project) : []), [project]);
  const hasMultipleProjectTeamspaceEntries = projectEntries.length > 1;
  const showBudgetedProjectEntries = budgetedProjectEntries.length > 1;
  const requiresProjectTeamspaceEntry = Boolean(project && hasMultipleProjectTeamspaceEntries);
  const projectConsumptionMinutes = project?.consumption_minutes ?? 0;
  const projectBudgetMinutes = project?.hour_budget_minutes ?? null;
  const projectConsumptionUsagePercent = project ? projectConsumptionPercent(projectConsumptionMinutes, projectBudgetMinutes) : null;
  const projectRemainingMinutes = projectBudgetMinutes && projectBudgetMinutes > 0 ? projectBudgetMinutes - projectConsumptionMinutes : null;
  const canEditProject = project?.can_edit !== false;
  const canEditTicketData = !project || canEditProject;
  const isProject = Boolean(project);
  const isGlobalTicket = periodType === "all";
  const isPeriodClosed = Boolean(data?.closed);
  const periodLabel = periodType === "month" ? "Monat" : periodType === "day" ? "Tag" : "Ticket";
  const sessionsScopeLabel = isGlobalTicket
    ? globalMonthFilter === "all"
      ? "im gesamten Ticketverlauf"
      : `im Monat ${globalMonthFilter}`
    : `im ${periodLabel.toLowerCase()} ${period}`;
  const teamspaceLabel = isGlobalTicket || periodType === "month" ? "Teamspace gesamt" : "Teamspace Tag";
  const availableMonths = data?.availableMonths ?? [];
  const selectedMonthHasSessions = availableMonths.some((month) => month.month === globalMonthFilter);
  const dayBillingMap = useMemo(() => new Map((data?.dayBillings ?? []).map((billing) => [billing.day, billing.billed_minutes])), [data?.dayBillings]);
  const savedDayBillingInput = (day: string) => formatHoursInput(dayBillingMap.get(day));
  const isDayBillingDirty = (day: string) => (dayBillingInputs[day] ?? "") !== savedDayBillingInput(day);
  const sessionGroups = useMemo(() => {
    const groups = new Map<
      string,
      { key: string; label: string; totalMinutes: number; nonBillableMinutes: number; openMinutes: number; sessions: SessionEntry[] }
    >();

    for (const session of data?.sessions ?? []) {
      const key = sessionDayKey(session.started_at);
      const group = groups.get(key);
      const billedMinutes = session.billing_status === "billed" ? session.rounded_minutes : 0;
      const nonBillableMinutes = session.billing_status === "non_billable" ? session.rounded_minutes : 0;
      const openMinutes = session.billing_status === null ? session.rounded_minutes : 0;

      if (group) {
        group.sessions.push(session);
        group.totalMinutes += billedMinutes;
        group.nonBillableMinutes += nonBillableMinutes;
        group.openMinutes += openMinutes;
        continue;
      }

      groups.set(key, {
        key,
        label: formatDate(session.started_at),
        totalMinutes: billedMinutes,
        nonBillableMinutes,
        openMinutes,
        sessions: [session]
      });
    }

    return Array.from(groups.values());
  }, [data?.sessions]);
  const sessionIds = useMemo(() => sessionGroups.flatMap((group) => group.sessions.map((session) => session.id)), [sessionGroups]);
  const allSessionsExpanded = sessionIds.length > 0 && sessionIds.every((sessionId) => expandedSessionIds.includes(sessionId));
  const periodTotalMinutes = sessionGroups.reduce((sum, group) => sum + group.totalMinutes, 0);
  const periodTeamspaceMinutes = Array.from(dayBillingMap.values()).reduce((sum, minutes) => sum + Number(minutes ?? 0), 0);
  const ticketDataDirty = Boolean(
    ticket &&
      (editTicketNumber !== ticket.ticket_number ||
        editTicketTitle !== (ticket.title ?? "") ||
        editOrganizationId !== (ticket.organization_id ?? "") ||
        editWorkType !== (ticket.work_type ?? "support"))
  );
  const todos = data?.todos ?? [];
  const visibleTodos = todoFilter === "all" ? todos : todos.filter((todo) => todo.status === todoFilter);
  const todoCounts = {
    open: todos.filter((todo) => todo.status === "open").length,
    done: todos.filter((todo) => todo.status === "done").length,
    all: todos.length
  };
  const hasUnsavedChanges = ticketDataDirty || sessionGroups.some((group) => isDayBillingDirty(group.key));

  useEffect(() => {
    setExpandedSessionIds((current) => current.filter((sessionId) => sessionIds.includes(sessionId)));
  }, [sessionIds]);

  useEffect(() => {
    if (!ticket) {
      return;
    }

    const ticketMonth = isGlobalTicket ? globalMonthFilter : periodType === "day" ? period.slice(0, 7) : period;

    onOpenTicketChange?.({
      key: `ticket:${ticket.id}`,
      ticketId: ticket.id,
      ticketNumber: ticket.ticket_number,
      periodType: "all",
      period: ticketMonth,
      path: `/tickets/${ticket.id}?month=${ticketMonth}`,
      returnPath,
      dirty: hasUnsavedChanges
    });
  }, [ticket, periodType, period, isGlobalTicket, globalMonthFilter, returnPath, hasUnsavedChanges, onOpenTicketChange]);

  useEffect(() => {
    let cancelled = false;

    if (!ticket?.ticket_number) {
      setIsFavorite(false);
      return;
    }

    async function loadFavoriteStatus() {
      try {
        const result = await getDashboardPreference();
        const favorites = Array.isArray(result.preference.favorites) ? result.preference.favorites : [];

        if (!cancelled) {
          setIsFavorite(favorites.some((favorite) => favorite.ticketNumber === ticket?.ticket_number));
        }
      } catch {
        if (!cancelled) {
          setIsFavorite(false);
        }
      }
    }

    void loadFavoriteStatus();

    return () => {
      cancelled = true;
    };
  }, [ticket?.ticket_number]);

  async function setBilling(sessionId: string, billingStatus: BillingStatus) {
    if (isPeriodClosed && billingStatus !== null) {
      toast.warning("Monat ist abgeschlossen", {
        description: "Öffne den Monat zuerst wieder, um Bewertungen zu ändern."
      });
      return;
    }

    setLoadingId(sessionId);
    try {
      await updateSessionBilling(sessionId, billingStatus);
      await load();
    } catch (error) {
      toast.error("Status konnte nicht gespeichert werden", {
        description: error instanceof Error ? error.message : "Unbekannter Fehler"
      });
    } finally {
      setLoadingId(null);
    }
  }

  function toggleSessionDetails(sessionId: string) {
    setExpandedSessionIds((current) =>
      current.includes(sessionId) ? current.filter((id) => id !== sessionId) : [...current, sessionId]
    );
  }

  function toggleAllSessionDetails() {
    setExpandedSessionIds(allSessionsExpanded ? [] : sessionIds);
  }

  async function saveDayBilling(day: string) {
    if (!ticket) {
      return;
    }

    if (isPeriodClosed) {
      toast.warning("Monat ist abgeschlossen", {
        description: "Öffne den Monat zuerst wieder, um Teamspace-Zeiten zu ändern."
      });
      return;
    }

    const parsedMinutes = parseHoursInput(dayBillingInputs[day] ?? "");

    if (parsedMinutes === undefined) {
      toast.error("Teamspace-Zeit prüfen", {
        description: "Bitte Stunden als positive Zahl eintragen, z.B. 1,5."
      });
      return;
    }

    const currentMinutes = dayBillingMap.get(day) ?? null;

    if (parsedMinutes === currentMinutes) {
      return;
    }

    setSavingDayBillingKey(day);
    try {
      await updateTicketDayBilling(ticket.id, day, parsedMinutes);
      toast.success("Zeit gespeichert");
      await load();
    } catch (error) {
      toast.error("Zeit konnte nicht gespeichert werden", {
        description: error instanceof Error ? error.message : "Unbekannter Fehler"
      });
    } finally {
      setSavingDayBillingKey(null);
    }
  }

  async function saveTicketData(event: FormEvent) {
    event.preventDefault();

    if (!ticket) {
      return;
    }

    if (!canEditTicketData) {
      toast.error("Projekt ist geteilt", {
        description: "Nur der Zammad-Owner kann Ticket- und Projektdaten ändern."
      });
      return;
    }

    if (!editOrganizationId) {
      toast.error("Organisation wählen");
      return;
    }

    const removeProjectData = Boolean(project && editWorkType === "support");

    if (removeProjectData) {
      const confirmed = window.confirm(
        `Ticket "${ticket.title || ticket.ticket_number}" auf Support umstellen? Projektdaten, Kontingent und Teamspace-Zeiten werden entfernt. Sessions und ToDos bleiben erhalten.`
      );

      if (!confirmed) {
        return;
      }
    }

    setSavingTicket(true);
    try {
      await updateTicket(ticket.id, {
        ticketNumber: editTicketNumber,
        title: editTicketTitle || null,
        organizationId: editOrganizationId,
        workType: editWorkType,
        removeProjectData
      });
      toast.success("Ticketdaten gespeichert", {
        description: editWorkType === "consulting" ? "Das Ticket ist jetzt als Projekt angelegt." : "Organisation und Art wurden auf die vorhandenen Sessions übernommen."
      });
      await load();
    } catch (error) {
      toast.error("Ticketdaten konnten nicht gespeichert werden", {
        description: error instanceof Error ? error.message : "Unbekannter Fehler"
      });
    } finally {
      setSavingTicket(false);
    }
  }

  function openProjectEditor() {
    if (!project) {
      return;
    }

    if (project.can_edit === false) {
      toast.error("Projekt ist geteilt", {
        description: "Nur der Zammad-Owner kann die Projektdaten bearbeiten."
      });
      return;
    }

    setProjectForm(projectEditForm(project));
    setEditingProject(true);
  }

  async function saveProjectData(event: FormEvent) {
    event.preventDefault();

    if (!project || !ticket) {
      return;
    }

    if (project.can_edit === false) {
      toast.error("Projekt ist geteilt", {
        description: "Nur der Zammad-Owner kann die Projektdaten bearbeiten."
      });
      return;
    }

    if (!projectForm.organizationId) {
      toast.error("Organisation wählen");
      return;
    }

    const teamspaceEntries = parseProjectTeamspaceEntryForms(projectForm.teamspaceEntries);

    if (!teamspaceEntries) {
      toast.error("Teamspace-Einträge prüfen", {
        description: "Bitte Stunden als Zahl eintragen, z.B. 12,5."
      });
      return;
    }

    const defaultTeamspaceEntry = teamspaceEntries.find((entry) => entry.isDefault) ?? teamspaceEntries[0];

    setSavingProject(true);
    try {
      await updateProject(project.id, {
        ticketNumber: ticket.ticket_number,
        title: projectForm.title || null,
        organizationId: projectForm.organizationId,
        teamspaceProject: defaultTeamspaceEntry.teamspaceProject,
        teamspaceEntries,
        description: projectForm.description,
        goals: "",
        startsOn: projectForm.startsOn || null,
        endsOn: projectForm.endsOn || null,
        hourBudgetMinutes: defaultTeamspaceEntry.hourBudgetMinutes,
        manualConsumptionMinutes: defaultTeamspaceEntry.manualConsumptionMinutes
      });
      toast.success("Projekt gespeichert");
      setEditingProject(false);
      await load();
    } catch (error) {
      toast.error("Projekt konnte nicht gespeichert werden", {
        description: error instanceof Error ? error.message : "Unbekannter Fehler"
      });
    } finally {
      setSavingProject(false);
    }
  }

  async function setProjectClosed(closed: boolean) {
    if (!project) {
      return;
    }

    if (project.can_edit === false) {
      toast.error("Projekt ist geteilt", {
        description: "Nur der Zammad-Owner kann den Projektstatus ändern."
      });
      return;
    }

    setSavingProjectStatus(true);
    try {
      await updateProjectStatus(project.id, closed);
      toast.success(closed ? "Projekt geschlossen" : "Projekt wieder geöffnet");
      await load();
    } catch (error) {
      toast.error("Projektstatus konnte nicht gespeichert werden", {
        description: error instanceof Error ? error.message : "Unbekannter Fehler"
      });
    } finally {
      setSavingProjectStatus(false);
    }
  }

  async function submitTicketSession(event: FormEvent) {
    event.preventDefault();

    if (!ticket) {
      return;
    }

    if (isRecurringBillingTicket) {
      toast.error("Fixe Abrechnung", {
        description: "Für fixe Abrechnungen dürfen keine Sessions nachgetragen werden. Bitte die Definition bearbeiten."
      });
      return;
    }

    const effectiveOrganizationId = ticket.organization_id ?? ticketSession.organizationId;
    const effectiveWorkType = ticket.work_type ?? ticketSession.workType;

    if (!effectiveOrganizationId) {
      toast.error("Organisation wählen");
      return;
    }

    if (effectiveWorkType === "consulting" && requiresProjectTeamspaceEntry && !ticketSession.projectTeamspaceEntryId) {
      toast.error("Teamspace-Eintrag wählen", {
        description: "Dieses Projekt hat mehrere Teamspace-Einträge."
      });
      return;
    }

    const startedAt = new Date(`${ticketSession.day}T${ticketSession.startTime}:00`);
    const endedAt = new Date(`${ticketSession.day}T${ticketSession.endTime}:00`);

    if (Number.isNaN(startedAt.getTime()) || Number.isNaN(endedAt.getTime())) {
      toast.error("Datum oder Uhrzeit prüfen");
      return;
    }

    if (endedAt <= startedAt) {
      toast.error("Ende muss nach Beginn liegen");
      return;
    }

    if (editSessionWorkType === "consulting" && requiresProjectTeamspaceEntry && !editSessionProjectTeamspaceEntryId) {
      toast.error("Teamspace-Eintrag wählen", {
        description: "Dieses Projekt hat mehrere Teamspace-Einträge."
      });
      return;
    }

    const durationSeconds = Math.floor((endedAt.getTime() - startedAt.getTime()) / 1000);

    setSavingTicketSession(true);

    try {
      await createSession({
        ticketNumber: ticket.ticket_number,
        organizationId: effectiveOrganizationId,
        activity: ticketSession.activity,
        workType: effectiveWorkType,
        startedAt: startedAt.toISOString(),
        endedAt: endedAt.toISOString(),
        durationSeconds,
        projectTeamspaceEntryId: effectiveWorkType === "consulting" && requiresProjectTeamspaceEntry ? ticketSession.projectTeamspaceEntryId : null
      });
      toast.success("Session nachgetragen", {
        description: "Der Eintrag wurde diesem Ticket zugeordnet. Betroffene Abschlüsse wurden wieder geöffnet."
      });
      setTicketSession({
        ...emptyTicketSessionForm(),
        organizationId: ticket.organization_id ?? "",
        organizationName: ticket.organization_name ?? null,
        projectTeamspaceEntryId: "",
        workType: ticket.work_type ?? "support",
        day: ticketSession.day
      });
      await load();
    } catch (error) {
      toast.error("Session konnte nicht nachgetragen werden", {
        description: error instanceof Error ? error.message : "Unbekannter Fehler"
      });
    } finally {
      setSavingTicketSession(false);
    }
  }

  function openSessionEditor(session: SessionEntry) {
    setEditingSession(session);
    setEditSessionOrganizationId(session.organization_id ?? "");
    setEditSessionOrganizationName(session.organization_name ?? null);
    setEditSessionActivity(session.activity);
    setEditSessionWorkType(session.work_type);
    setEditSessionProjectTeamspaceEntryId(session.project_teamspace_entry_id ?? "");
    setEditSessionDay(toDateLocalValue(session.started_at));
    setEditSessionStartTime(toTimeLocalValue(session.started_at));
    setEditSessionEndTime(toTimeLocalValue(session.ended_at));
  }

  function openTeamspacePreparation(group: (typeof sessionGroups)[number]) {
    setTeamspacePreparation({
      day: group.key,
      label: group.label,
      text: teamspacePreparationText(ticket, group.sessions)
    });
  }

  async function copyTeamspacePreparation() {
    if (!teamspacePreparation) {
      return;
    }

    try {
      await writeTextToClipboard(teamspacePreparation.text);
      toast.success("TS Aufbereitung kopiert", {
        description: teamspacePreparation.label
      });
    } catch (error) {
      toast.error("TS Aufbereitung konnte nicht kopiert werden", {
        description: error instanceof Error ? error.message : "Zwischenablage nicht verfügbar"
      });
    }
  }

  async function saveSessionData(event: FormEvent) {
    event.preventDefault();

    if (!editingSession) {
      return;
    }

    if (!editSessionOrganizationId) {
      toast.error("Organisation wählen");
      return;
    }

    const startedAt = new Date(`${editSessionDay}T${editSessionStartTime}:00`);
    const endedAt = new Date(`${editSessionDay}T${editSessionEndTime}:00`);

    if (Number.isNaN(startedAt.getTime()) || Number.isNaN(endedAt.getTime())) {
      toast.error("Beginn und Ende prüfen");
      return;
    }

    if (endedAt <= startedAt) {
      toast.error("Ende muss nach Beginn liegen");
      return;
    }

    const removeProjectData = Boolean(project && editingSession.work_type === "consulting" && editSessionWorkType === "support");

    if (removeProjectData) {
      const confirmed = window.confirm(
        `Session auf Support umstellen? Falls dadurch keine Consulting-Sessions mehr für "${ticket?.title || ticket?.ticket_number || "dieses Ticket"}" bleiben, werden Projektdaten, Kontingent und Teamspace-Zeiten entfernt. Sessions und ToDos bleiben erhalten.`
      );

      if (!confirmed) {
        return;
      }
    }

    setSavingSessionDetails(true);
    try {
      await updateSessionDetails(editingSession.id, {
        organizationId: editSessionOrganizationId,
        activity: editSessionActivity,
        workType: editSessionWorkType,
        removeProjectData,
        projectTeamspaceEntryId: editSessionWorkType === "consulting" && requiresProjectTeamspaceEntry ? editSessionProjectTeamspaceEntryId : null,
        startedAt: startedAt.toISOString(),
        endedAt: endedAt.toISOString()
      });
      toast.success("Session aktualisiert");
      setEditingSession(null);
      await load();
    } catch (error) {
      toast.error("Session konnte nicht gespeichert werden", {
        description: error instanceof Error ? error.message : "Unbekannter Fehler"
      });
    } finally {
      setSavingSessionDetails(false);
    }
  }

  async function removeSession(session: SessionEntry) {
    const confirmed = window.confirm(`Session vom ${formatDateTime(session.started_at)} wirklich löschen?`);

    if (!confirmed) {
      return;
    }

    setDeletingId(session.id);
    try {
      const result = await deleteSession(session.id);

      if (result.deleted.projectDeleteAvailable && result.deleted.project_id) {
        setPendingProjectDelete({ projectId: result.deleted.project_id });
        toast.success("Session gelöscht", {
          description: "Für dieses Projekt sind keine Sessions mehr vorhanden."
        });
        return;
      }

      if (result.deleted.ticketDeleted || result.deleted.userTicketEmpty) {
        toast.success("Letzte Session gelöscht", {
          description: result.deleted.ticketDeleted ? "Das leere Ticket wurde entfernt." : "Für dich gibt es zu diesem Ticket keine Einträge mehr."
        });
        onNavigate(returnPath);
        return;
      }

      toast.success("Session gelöscht", {
        description: "Betroffene Abschlüsse wurden wieder geöffnet."
      });
      await load();
    } catch (error) {
      toast.error("Session konnte nicht gelöscht werden", {
        description: error instanceof Error ? error.message : "Unbekannter Fehler"
      });
    } finally {
      setDeletingId(null);
    }
  }

  async function keepEmptyProject() {
    setPendingProjectDelete(null);
    toast.success("Projekt behalten");
    await load();
  }

  async function deleteEmptyProject() {
    if (!pendingProjectDelete) {
      return;
    }

    setDeletingEmptyProject(true);
    try {
      await deleteProject(pendingProjectDelete.projectId);
      toast.success("Projekt gelöscht");
      setPendingProjectDelete(null);
      onNavigate(returnPath);
    } catch (error) {
      toast.error("Projekt konnte nicht gelöscht werden", {
        description: error instanceof Error ? error.message : "Unbekannter Fehler"
      });
    } finally {
      setDeletingEmptyProject(false);
    }
  }

  async function toggleTicketFavorite() {
    if (!ticket?.ticket_number) {
      return;
    }

    setSavingFavorite(true);
    try {
      if (isFavorite) {
        await removeFavoriteTicket(ticket.ticket_number);
        setIsFavorite(false);
        toast.success("Favorit entfernt", {
          description: ticket.ticket_number
        });
        return;
      }

      await addFavoriteTicket(ticket.ticket_number);
      setIsFavorite(true);
      toast.success("Favorit gespeichert", {
        description: ticket.ticket_number
      });
    } catch (error) {
      toast.error(isFavorite ? "Favorit konnte nicht entfernt werden" : "Favorit konnte nicht gespeichert werden", {
        description: error instanceof Error ? error.message : "Unbekannter Fehler"
      });
    } finally {
      setSavingFavorite(false);
    }
  }

  return (
    <div className="space-y-4">
      <div className="flex flex-col gap-3 lg:flex-row lg:items-end lg:justify-between">
        <div>
          <Button variant="ghost" size="sm" className="-ml-2 mb-1 h-8" onClick={() => onNavigate(returnPath)}>
            <ArrowLeft className="size-4" />
            Zurück
          </Button>
          <div className="flex flex-wrap items-center gap-2">
            <h2 className="text-xl font-semibold tracking-normal sm:text-2xl">{ticket?.title || ticket?.ticket_number || "Ticket"}</h2>
            
            {isProject ? <Badge variant="outline">Projekt</Badge> : null}
            <ZammadStateBadge stateId={ticket?.zammad_state_id} />
            <ZammadPriorityBadge priorityId={ticket?.zammad_priority_id} />
            {(periodType === "month" || (isGlobalTicket && globalMonthFilter !== "all")) && data?.closed ? <Badge variant="outline">Monat geschlossen</Badge> : null}
            {ticket?.ticket_number ? <CopyTicketButton ticketNumber={ticket.ticket_number} /> : null}
          </div>
          <p className="text-sm text-muted-foreground">
            {ticket?.title ? `${ticket.ticket_number} · ` : ""}
            Sessions {sessionsScopeLabel}
          </p>
        </div>

        <div className="flex flex-wrap items-center gap-2">
          {ticket?.ticket_number ? (
            <Button type="button" size="sm" variant={isFavorite ? "default" : "secondary"} disabled={savingFavorite} onClick={() => void toggleTicketFavorite()}>
              <Star className={cn("size-4", isFavorite && "fill-current")} />
              {isFavorite ? "Favorit entfernen" : "Favorit"}
            </Button>
          ) : null}
          <Badge variant={data?.openCount === 0 ? "success" : "warning"}>
            {data?.openCount === 0 ? "Bewertet" : `${data?.openCount ?? 0} offen`}
          </Badge>
        </div>
      </div>

      {(periodType === "month" || (isGlobalTicket && globalMonthFilter !== "all")) && data?.closed ? (
        <Alert variant="success" className="py-3 text-sm">
          Dieser Monat ist abgeschlossen. Bewertungen und Änderungen sind geschützt, bis du den Monat im Monatsabschluss wieder öffnest.
        </Alert>
      ) : null}

      {isGlobalTicket ? (
        <Card>
          <CardHeader className="p-4">
            <CardTitle>Filter</CardTitle>
            <CardDescription>Grenzt die Sessionliste dieses Tickets ein. Die Ticketdaten selbst bleiben global.</CardDescription>
          </CardHeader>
          <CardContent className="grid gap-3 px-4 pb-4 md:grid-cols-3">
            <div className="space-y-2">
              <label className="text-sm font-medium" htmlFor="ticket-month-filter">Monat</label>
              <select
                id="ticket-month-filter"
                className="h-8 w-full rounded-lg border border-input bg-background px-2 text-sm focus-visible:outline-none focus-visible:ring-3 focus-visible:ring-ring/50"
                value={globalMonthFilter}
                onChange={(event) => setGlobalMonthFilter(event.currentTarget.value)}
              >
                <option value="all">Alle Monate</option>
                {globalMonthFilter !== "all" && !selectedMonthHasSessions ? <option value={globalMonthFilter}>{globalMonthFilter} (0)</option> : null}
                {availableMonths.map((month) => (
                  <option key={month.month} value={month.month}>
                    {month.month} ({month.session_count})
                  </option>
                ))}
              </select>
            </div>
            <div className="space-y-2">
              <label className="text-sm font-medium" htmlFor="ticket-status-filter">Bewertung</label>
              <select
                id="ticket-status-filter"
                className="h-8 w-full rounded-lg border border-input bg-background px-2 text-sm focus-visible:outline-none focus-visible:ring-3 focus-visible:ring-ring/50"
                value={globalStatusFilter}
                onChange={(event) => setGlobalStatusFilter(event.currentTarget.value as typeof globalStatusFilter)}
              >
                <option value="all">Alle Bewertungen</option>
                <option value="open">Offen</option>
                <option value="billed">Abgerechnet</option>
                <option value="non_billable">Nicht abrechenbar</option>
              </select>
            </div>
          </CardContent>
        </Card>
      ) : null}

      <Card>
        <CardHeader className="p-4">
          <div className="flex items-start justify-between gap-3">
            <div>
              <CardTitle>Ticketdaten</CardTitle>
              <CardDescription>
                {canEditTicketData
                  ? "Änderungen an Organisation und Art werden auf alle vorhandenen Sessions dieses Tickets übernommen."
                  : "Dieses Projekt ist geteilt. Nur der Zammad-Owner kann Ticket- und Projektdaten ändern."}
              </CardDescription>
            </div>
            <HelpLink anchor="ticketdaten" label="Hilfe zu Ticketdaten" />
          </div>
        </CardHeader>
        <CardContent className="px-4 pb-4">
          <form className="grid gap-3 lg:grid-cols-[180px_minmax(220px,1fr)_minmax(220px,1fr)_160px_auto] lg:items-end" onSubmit={saveTicketData}>
            <div className="space-y-2">
              <label className="text-sm font-medium" htmlFor="edit-ticket-number">Ticketnummer</label>
              <Input id="edit-ticket-number" value={editTicketNumber} disabled={!canEditTicketData} onChange={(event) => setEditTicketNumber(event.currentTarget.value)} required />
            </div>
            <div className="space-y-2">
              <label className="text-sm font-medium" htmlFor="edit-ticket-title">Titel</label>
              <Input id="edit-ticket-title" value={editTicketTitle} disabled={!canEditTicketData} onChange={(event) => setEditTicketTitle(event.currentTarget.value)} placeholder="optional" />
            </div>
            <div className="space-y-2">
              <label className="text-sm font-medium" htmlFor="edit-ticket-organization">Organisation</label>
              {ticket?.customer_name && !ticket.organization_id ? (
                <p className="text-xs text-muted-foreground">Bisheriger Freitext: {ticket.customer_name}</p>
              ) : null}
              <OrganizationSelect
                value={editOrganizationId}
                selectedName={editOrganizationName}
                disabled={!canEditTicketData}
                onChange={(organization) => {
                  setEditOrganizationId(organization.id);
                  setEditOrganizationName(organization.name);
                }}
                required
              />
            </div>
            <div className="space-y-2">
              <label className="text-sm font-medium" htmlFor="edit-ticket-work-type">Art</label>
              <select
                id="edit-ticket-work-type"
                className="h-8 w-full rounded-lg border border-input bg-background px-2 text-sm focus-visible:outline-none focus-visible:ring-3 focus-visible:ring-ring/50"
                value={editWorkType}
                disabled={!canEditTicketData}
                onChange={(event) => setEditWorkType(event.currentTarget.value as WorkType)}
              >
                <option value="support">Support</option>
                <option value="consulting">Consulting</option>
              </select>
            </div>
            <Button type="submit" disabled={!canEditTicketData || savingTicket}>
              <Save className="size-4" />
              {savingTicket ? "Speichert..." : "Speichern"}
            </Button>
          </form>
        </CardContent>
      </Card>

      <div className={cn("grid gap-4", project && "xl:grid-cols-2")}>
        {project ? (
          <Card>
          <CardHeader className="p-4">
            <div className="flex items-start justify-between gap-3">
              <div>
                <CardTitle className="flex items-center gap-2">
                  <FolderKanban className="size-5 text-muted-foreground" />
                  Projekt
                  {project.closed_at ? <Badge variant="secondary">Geschlossen</Badge> : <Badge variant="success">Offen</Badge>}
                  <ZammadStateBadge stateId={project.zammad_state_id} />
                  <ZammadPriorityBadge priorityId={project.zammad_priority_id} />
                  {!canEditProject ? <Badge variant="outline">geteilt</Badge> : null}
                  {project.close_review_required ? <Badge variant="warning">TS/TT prüfen</Badge> : null}
                  {(project.unassigned_teamspace_session_count ?? 0) > 0 ? <Badge variant="warning">{project.unassigned_teamspace_session_count} ohne TS</Badge> : null}
                </CardTitle>
                <CardDescription>
                  {!canEditProject && project.owner_display_name
                    ? `Eigentümer: ${project.owner_display_name}`
                    : showBudgetedProjectEntries
                      ? `${budgetedProjectEntries.length} budgetierte Teamspace-Einträge`
                      : budgetedProjectEntries[0]?.teamspace_project || project.teamspace_project || "Kein Teamspace-Projekt hinterlegt"}
                </CardDescription>
              </div>
              <div className="flex shrink-0 items-center gap-1">
                <Button
                  type="button"
                  size="sm"
                  variant="secondary"
                  disabled={!canEditProject || savingProjectStatus}
                  onClick={() => void setProjectClosed(!project.closed_at)}
                >
                  {project.closed_at ? <RotateCcw className="size-4" /> : <CheckCircle2 className="size-4" />}
                  {project.closed_at ? "Öffnen" : "Schließen"}
                </Button>
                <Button type="button" size="sm" variant="secondary" disabled={!canEditProject} onClick={openProjectEditor}>
                  <Pencil className="size-4" />
                  Bearbeiten
                </Button>
                <HelpLink anchor="projekte" label="Hilfe zu Projekten" />
              </div>
            </div>
          </CardHeader>
          <CardContent className="space-y-3 px-4 pb-4">
            {(project.unassigned_teamspace_session_count ?? 0) > 0 ? (
              <Alert variant="warning">
                <div className="font-medium">Nicht zugeordnete Sessions</div>
                <div className="text-sm text-muted-foreground">
                  {project.unassigned_teamspace_session_count} Session(s) haben keinen Teamspace-Eintrag. Bitte über die Session-Bearbeitung neu zuordnen.
                </div>
              </Alert>
            ) : null}
            {project.close_review_required ? (
              <Alert variant="warning">
                <div className="font-medium">Zeiten prüfen</div>
                <div className="text-sm text-muted-foreground">
                  Zammad meldet dieses Consulting-Ticket als geschlossen. Bitte Zeiten in Teamspace und TicketTracker prüfen und das Projekt danach schließen.
                </div>
              </Alert>
            ) : null}
            <div className="flex flex-wrap gap-2 text-sm">
              <Badge variant="secondary">Zeitraum {project.starts_on || "offen"} - {project.ends_on || "offen"}</Badge>
              <Badge variant="secondary">Kontingent {projectBudgetMinutes ? formatMinutes(projectBudgetMinutes) : "offen"}</Badge>
              <Badge variant="secondary">Verbrauch {formatMinutes(projectConsumptionMinutes)}</Badge>
              <Badge variant={projectRemainingMinutes !== null && projectRemainingMinutes < 0 ? "destructive" : "secondary"}>{projectRemainingLabel(projectRemainingMinutes)}</Badge>
              {showBudgetedProjectEntries ? <Badge variant="outline">{budgetedProjectEntries.length} Budgets</Badge> : null}
            </div>
            <div className="space-y-2">
              <div>
                <div className="mb-1 flex items-center justify-between gap-2 text-xs text-muted-foreground">
                  <span>Budgetverbrauch</span>
                  <span className="shrink-0 text-right">
                    {projectBudgetMinutes && projectBudgetMinutes > 0
                      ? `${formatMinutes(projectConsumptionMinutes)} / ${formatMinutes(projectBudgetMinutes)} · ${projectRemainingLabel(projectRemainingMinutes)}`
                      : `${formatMinutes(projectConsumptionMinutes)} / offen`}
                  </span>
                </div>
                <div
                  className="h-2 overflow-hidden rounded-full bg-muted"
                  title={projectConsumptionUsagePercent !== null ? `${projectConsumptionUsagePercent}% Verbrauch` : "ohne Gesamtbudget"}
                  aria-label={projectConsumptionUsagePercent !== null ? `${projectConsumptionUsagePercent}% Verbrauch` : "ohne Gesamtbudget"}
                >
                  <div
                    className={cn("h-full rounded-full", projectConsumptionUsagePercent === null ? "bg-muted-foreground/20" : projectConsumptionBarClass(projectConsumptionUsagePercent))}
                    style={{ width: `${projectConsumptionUsagePercent === null ? 0 : Math.min(100, projectConsumptionUsagePercent)}%` }}
                  />
                </div>
              </div>
              <div className="grid gap-1.5 md:grid-cols-2">
                {budgetedProjectEntries.map((entry) => {
                  const consumption = Number(entry.consumption_minutes ?? 0);
                  const percent = projectConsumptionPercent(consumption, entry.hour_budget_minutes);
                  const label = entry.teamspace_project || (entry.is_default ? "Standard" : "Ohne Teamspace-ID");

                  return (
                    <div key={entry.id} className="rounded-md border bg-background/50 px-2 py-1">
                      <div className="mb-1 flex min-w-0 items-center justify-between gap-2 text-[11px]">
                        <span className="truncate text-muted-foreground">
                          {label}
                          {entry.is_default ? " · Standard" : ""}
                          {entry.budget_sync_disabled ? " · Budget geschützt" : ""}
                        </span>
                        <span className="shrink-0 font-medium">
                          {formatMinutes(consumption)} / {entry.hour_budget_minutes ? formatMinutes(entry.hour_budget_minutes) : "offen"}
                        </span>
                      </div>
                      <div className="h-1 overflow-hidden rounded-full bg-muted">
                        <div
                          className={cn("h-full rounded-full", percent === null ? "bg-muted-foreground/20" : projectConsumptionBarClass(percent))}
                          style={{ width: `${percent === null ? 0 : Math.min(100, percent)}%` }}
                        />
                      </div>
                    </div>
                  );
                })}
              </div>
            </div>
            <div className="text-sm">
              <div className="min-w-0">
                <div className="mb-1 flex items-center gap-2 font-medium">
                  <FolderKanban className="size-4 text-muted-foreground" />
                  Beschreibung/Ziele
                </div>
                <p className={cn("whitespace-pre-wrap text-muted-foreground", !projectDescriptionExpanded && "line-clamp-4")}>
                  {projectDescription || "Noch keine Beschreibung/Ziele."}
                </p>
                {projectDescription ? (
                  <Button
                    type="button"
                    size="sm"
                    variant="ghost"
                    className="mt-1 h-7 px-2 text-xs"
                    onClick={() => setProjectDescriptionExpanded((current) => !current)}
                  >
                    {projectDescriptionExpanded ? (
                      <>
                        <ChevronUp className="size-3.5" />
                        Einklappen
                      </>
                    ) : (
                      <>
                        <ChevronDown className="size-3.5" />
                        Vollständig anzeigen
                      </>
                    )}
                  </Button>
                ) : null}
              </div>
            </div>
          </CardContent>
          </Card>
        ) : null}

        <Dialog open={editingProject} onOpenChange={setEditingProject}>
          <DialogContent className="max-h-[calc(100dvh-2rem)] overflow-y-auto sm:max-w-3xl">
            <DialogHeader>
              <DialogTitle>Projekt bearbeiten</DialogTitle>
              <DialogDescription>Projektinformationen zum geöffneten Ticket aktualisieren.</DialogDescription>
            </DialogHeader>
            <form className="space-y-4" onSubmit={saveProjectData}>
              <div className="grid gap-3 lg:grid-cols-[minmax(220px,1fr)_minmax(220px,1fr)]">
                <div className="space-y-2">
                  <label className="text-sm font-medium" htmlFor="project-edit-title">Titel</label>
                  <Input
                    id="project-edit-title"
                    value={projectForm.title}
                    onChange={(event) => setProjectForm({ ...projectForm, title: event.currentTarget.value })}
                    placeholder="optional"
                  />
                </div>
                <div className="space-y-2">
                  <label className="text-sm font-medium">Organisation</label>
                  <OrganizationSelect
                    value={projectForm.organizationId}
                    selectedName={projectForm.organizationName}
                    onChange={(organization) =>
                      setProjectForm({
                        ...projectForm,
                        organizationId: organization.id,
                        organizationName: organization.name
                      })
                    }
                    required
                  />
                </div>
              </div>
              <div className="grid gap-3 sm:grid-cols-2">
                <div className="space-y-2">
                  <label className="text-sm font-medium" htmlFor="project-edit-start">Von</label>
                  <Input id="project-edit-start" type="date" value={projectForm.startsOn} onChange={(event) => setProjectForm({ ...projectForm, startsOn: event.currentTarget.value })} />
                </div>
                <div className="space-y-2">
                  <label className="text-sm font-medium" htmlFor="project-edit-end">Bis</label>
                  <Input id="project-edit-end" type="date" value={projectForm.endsOn} onChange={(event) => setProjectForm({ ...projectForm, endsOn: event.currentTarget.value })} />
                </div>
              </div>
              <ProjectTeamspaceEntriesEditor
                entries={projectForm.teamspaceEntries}
                onChange={(teamspaceEntries) => setProjectForm({ ...projectForm, teamspaceEntries })}
              />
              <div className="space-y-2">
                <label className="text-sm font-medium" htmlFor="project-edit-description">Beschreibung/Ziele</label>
                <Textarea
                  id="project-edit-description"
                  className="min-h-32"
                  value={projectForm.description}
                  onChange={(event) => setProjectForm({ ...projectForm, description: event.currentTarget.value })}
                />
              </div>
              <div className="flex flex-wrap justify-end gap-2">
                <Button
                  type="button"
                  variant="secondary"
                  disabled={savingProjectStatus}
                  onClick={() => void setProjectClosed(!project?.closed_at)}
                >
                  {project?.closed_at ? <RotateCcw className="size-4" /> : <CheckCircle2 className="size-4" />}
                  {project?.closed_at ? "Wieder öffnen" : "Projekt schließen"}
                </Button>
                <Button type="submit" disabled={savingProject}>
                  <Save className="size-4" />
                  {savingProject ? "Speichert..." : "Projekt speichern"}
                </Button>
              </div>
            </form>
          </DialogContent>
        </Dialog>

        <Card>
          <CardHeader className="p-4">
            <div className="flex items-start justify-between gap-3">
              <div>
                <CardTitle className="flex items-center gap-2">
                  <ClipboardList className="size-5 text-muted-foreground" />
                  ToDos
                </CardTitle>
                <CardDescription>Aufgaben zu diesem Ticket oder Projekt verwalten.</CardDescription>
              </div>
              <div className="flex shrink-0 items-center gap-2">
                <div className="flex rounded-md border bg-muted/20 p-0.5">
                  {(["open", "all", "done"] as const).map((value) => (
                    <Button
                      key={value}
                      type="button"
                      size="sm"
                      variant={todoFilter === value ? "default" : "ghost"}
                      className="h-7 px-2 text-xs"
                      onClick={() => setTodoFilter(value)}
                    >
                      {value === "open" ? `Offen ${todoCounts.open}` : value === "done" ? `Erledigt ${todoCounts.done}` : `Alle ${todoCounts.all}`}
                    </Button>
                  ))}
                </div>
                <HelpLink anchor="todos" label="Hilfe zu ToDos" />
              </div>
            </div>
          </CardHeader>
          <CardContent className="px-4 pb-4">
            <TodoPanel ticketId={ticket?.id} todos={visibleTodos} onChanged={load} />
          </CardContent>
        </Card>
      </div>

      <Card>
        <CardHeader className="gap-3 p-4 sm:flex-row sm:items-start sm:justify-between sm:space-y-0">
          <div>
            <CardTitle>Session-Einträge</CardTitle>
            <CardDescription>Wähle für jede Session genau eine Bewertung aus oder lösche falsche Einträge.</CardDescription>
          </div>
          <div className="flex flex-wrap items-center gap-2">
            <div className="flex items-center gap-2 rounded-md border bg-muted/30 px-3 py-2 text-sm">
              <span className="text-muted-foreground">Abgerechnet</span>
              <span className="font-semibold">{formatMinutes(periodTotalMinutes)}</span>
            </div>
            <div className="flex items-center gap-2 rounded-md border bg-muted/30 px-3 py-2 text-sm">
              <span className="text-muted-foreground">{teamspaceLabel}</span>
              <span className="font-semibold">{formatMinutes(periodTeamspaceMinutes)}</span>
            </div>
            <HelpLink anchor="ticketdetail" label="Hilfe zur Ticketdetailansicht" />
          </div>
        </CardHeader>
        <CardContent className="px-4 pb-4">
          {data?.sessions.length ? (
            <div className="mb-3 flex justify-end">
              <Button type="button" size="sm" variant="secondary" onClick={toggleAllSessionDetails}>
                {allSessionsExpanded ? (
                  <>
                    <ChevronUp className="size-4" />
                    Alle einklappen
                  </>
                ) : (
                  <>
                    <ChevronDown className="size-4" />
                    Alle aufklappen
                  </>
                )}
              </Button>
            </div>
          ) : null}

          <div className="space-y-2">
            {sessionGroups.map((group) => (
              <div key={group.key} className="rounded-md border bg-background">
                <div className="grid min-w-0 gap-2 border-b bg-muted/25 px-3 py-2 lg:grid-cols-[minmax(180px,1fr)_auto] lg:items-center">
                  <div className="min-w-0 text-left">
                    <p className="truncate font-medium">{group.label}</p>
                    <p className="text-xs text-muted-foreground">{group.sessions.length} Session(s)</p>
                  </div>
                  <div className="grid w-full gap-2 sm:grid-cols-[13rem_10rem_8rem] xl:w-auto xl:grid-cols-[13rem_10rem_8rem_auto] xl:items-center xl:justify-end">
                    <Button type="button" size="sm" variant="secondary" className="h-7 w-full justify-center" onClick={() => openTeamspacePreparation(group)}>
                      <ClipboardList className="size-3.5" />
                      TS Aufbereitung
                    </Button>
                    <Badge variant="outline" className="flex h-7 w-full justify-center whitespace-nowrap">
                      Abgerechnet {formatMinutes(group.totalMinutes)}
                    </Badge>
                    <Badge variant={group.openMinutes > 0 ? "warning" : "success"} className="flex h-7 w-full justify-center whitespace-nowrap">
                      Offen {formatMinutes(group.openMinutes)}
                    </Badge>
                    <div className="flex items-center gap-2 text-xs text-muted-foreground sm:col-span-3 xl:col-span-1">
                      <label htmlFor={`crm-billing-${group.key}`}>Teamspace</label>
                      <Input
                        id={`crm-billing-${group.key}`}
                        type="text"
                        className="h-7 w-24 bg-background text-right"
                        autoComplete="off"
                        inputMode="decimal"
                        value={dayBillingInputs[group.key] ?? ""}
                        disabled={isPeriodClosed || savingDayBillingKey === group.key}
                        placeholder="0"
                        onChange={(event) => {
                          const nextValue = event.currentTarget.value;

                          if (!isPartialHoursInput(nextValue)) {
                            return;
                          }

                          setDayBillingInputs((current) => ({
                            ...current,
                            [group.key]: nextValue
                          }));
                        }}
                        onKeyDown={(event) => {
                          if (event.key === "Enter") {
                            event.preventDefault();
                          }
                        }}
                      />
                      <span>h</span>
                      <Button
                        type="button"
                        size="sm"
                        className={cn("h-7 w-[104px]", !isDayBillingDirty(group.key) && "invisible")}
                        disabled={isPeriodClosed || !isDayBillingDirty(group.key) || savingDayBillingKey === group.key}
                        onMouseDown={(event) => event.preventDefault()}
                        onClick={() => void saveDayBilling(group.key)}
                      >
                        <Save className="size-3.5" />
                        {savingDayBillingKey === group.key ? "Speichert..." : "Speichern"}
                      </Button>
                    </div>
                    {group.nonBillableMinutes > 0 ? (
                      <Badge variant="secondary" className="flex h-7 w-full justify-center whitespace-nowrap sm:col-span-3 xl:col-span-1 xl:col-start-2">
                        Nicht {formatMinutes(group.nonBillableMinutes)}
                      </Badge>
                    ) : null}
                  </div>
                </div>
                <div className="space-y-1.5 p-2 sm:p-3">
                  {group.sessions.map((session) => {
                    const expanded = expandedSessionIds.includes(session.id);

                    return (
                      <div key={session.id} className="ml-3 rounded-md border bg-card/40 sm:ml-6">
                        <div className="grid gap-2 p-2 lg:grid-cols-[220px_100px_minmax(260px,auto)_auto] lg:items-center">
                          <button
                            type="button"
                            className="flex min-w-0 items-center gap-2 rounded-md text-left text-sm text-muted-foreground hover:cursor-pointer hover:text-foreground focus-visible:outline-none focus-visible:ring-3 focus-visible:ring-ring/50"
                            onClick={() => toggleSessionDetails(session.id)}
                            aria-expanded={expanded}
                          >
                            {expanded ? <ChevronUp className="size-4 shrink-0" /> : <ChevronDown className="size-4 shrink-0" />}
                            <span className="truncate">
                              {formatTimeRange(session.started_at, session.ended_at)}
                            </span>
                          </button>
                          <div className="flex flex-wrap gap-1">
                            <Badge variant="outline" className="w-fit">{formatMinutes(session.rounded_minutes)}</Badge>
                            {session.recurring_billing_id ? <Badge variant="secondary">fix</Badge> : null}
                            {requiresProjectTeamspaceEntry ? (
                              session.project_teamspace_entry_id ? (
                                <Badge variant="info">{session.project_teamspace_project || "Teamspace"}</Badge>
                              ) : (
                                <Badge variant="warning">ohne Teamspace</Badge>
                              )
                            ) : null}
                          </div>
                          <BillingButtons
                            session={session}
                            disabled={isPeriodClosed}
                            loading={loadingId === session.id}
                            onChange={(value) => setBilling(session.id, value)}
                          />
                          <div className="flex gap-1 lg:justify-end">
                            <Button size="icon" variant="ghost" className="size-8" onClick={() => openSessionEditor(session)}>
                              <Pencil className="size-4" />
                              <span className="sr-only">Session bearbeiten</span>
                            </Button>
                            <Button
                              size="icon"
                              variant="ghost"
                              className="size-8 text-destructive hover:text-destructive"
                              disabled={deletingId === session.id}
                              onClick={() => removeSession(session)}
                            >
                              <Trash2 className="size-4" />
                              <span className="sr-only">Session löschen</span>
                            </Button>
                          </div>
                        </div>
                        {expanded ? (
                          <div className="border-t px-3 pb-3 pt-2">
                            <p className="whitespace-pre-wrap break-words text-sm font-medium">{session.activity}</p>
                            <div className="mt-2 flex flex-wrap gap-x-3 gap-y-1 text-xs text-muted-foreground">
                              <span>{session.organization_name ?? session.customer_name}</span>
                              <span>{session.work_type === "support" ? "Support" : "Consulting"}</span>
                              <span>Erfasst {formatDateTime(session.created_at)}</span>
                            </div>
                          </div>
                        ) : null}
                      </div>
                    );
                  })}
                </div>
              </div>
            ))}
          </div>

          {data?.sessions.length === 0 ? (
            <p className="py-8 text-center text-sm text-muted-foreground">Keine Sessions für dieses Ticket im gewählten Filter.</p>
          ) : null}
        </CardContent>
      </Card>
      {isRecurringBillingTicket ? (
        <Alert variant="warning">
          <div className="font-medium">Fixe Abrechnung</div>
          <div className="text-sm text-muted-foreground">Sessions für dieses Ticket werden ausschließlich aus der Definition erzeugt. Manuelles Nachtragen ist deaktiviert.</div>
        </Alert>
      ) : (
        <Card>
          <CardHeader className="p-4">
            <div className="flex items-start justify-between gap-3">
              <div>
                <CardTitle>Session nachtragen</CardTitle>
                <CardDescription>Neue Zeit direkt diesem Ticket zuordnen.</CardDescription>
              </div>
              <HelpLink anchor="session-nachtragen" label="Hilfe zum Nachtragen von Sessions" />
            </div>
          </CardHeader>
          <CardContent className="px-4 pb-4">
            <form className="space-y-4" onSubmit={submitTicketSession}>
              {ticket?.organization_id && ticket.work_type ? (
                <div className="grid gap-2 rounded-md border bg-muted/30 p-3 text-sm sm:grid-cols-[1fr_auto] sm:items-center">
                  <span className="font-medium">{ticket.organization_name ?? ticket.customer_name}</span>
                  <Badge variant="outline">{ticket.work_type === "support" ? "Support" : "Consulting"}</Badge>
                </div>
              ) : (
                <div className="grid gap-3 lg:grid-cols-[minmax(220px,1fr)_180px]">
                  <div className="space-y-2">
                    <label className="text-sm font-medium">Organisation</label>
                    {ticket?.customer_name && !ticket.organization_id ? (
                      <p className="text-xs text-muted-foreground">Bisheriger Freitext: {ticket.customer_name}</p>
                    ) : null}
                    <OrganizationSelect
                      value={ticketSession.organizationId}
                      selectedName={ticketSession.organizationName}
                      onChange={(organization) =>
                        setTicketSession({
                          ...ticketSession,
                          organizationId: organization.id,
                          organizationName: organization.name
                        })
                      }
                      required
                    />
                  </div>
                  <div className="space-y-2">
                    <label className="text-sm font-medium" htmlFor="ticket-session-work-type">
                      Art
                    </label>
                    <select
                      id="ticket-session-work-type"
                      className="h-8 w-full rounded-lg border border-input bg-background px-2 text-sm focus-visible:outline-none focus-visible:ring-3 focus-visible:ring-ring/50"
                      value={ticketSession.workType}
                      onChange={(event) => setTicketSession({ ...ticketSession, workType: event.currentTarget.value as WorkType })}
                    >
                      <option value="support">Support</option>
                      <option value="consulting">Consulting</option>
                    </select>
                  </div>
                </div>
              )}

              {requiresProjectTeamspaceEntry ? (
                <div className="space-y-2">
                  <label className="text-sm font-medium" htmlFor="ticket-session-teamspace-entry">Teamspace-Eintrag</label>
                  <select
                    id="ticket-session-teamspace-entry"
                    className="h-9 w-full rounded-lg border border-input bg-background px-2 text-sm focus-visible:outline-none focus-visible:ring-3 focus-visible:ring-ring/50"
                    value={ticketSession.projectTeamspaceEntryId}
                    onChange={(event) => setTicketSession({ ...ticketSession, projectTeamspaceEntryId: event.currentTarget.value })}
                    required
                  >
                    <option value="">Bitte wählen</option>
                    {projectEntries.map((entry) => (
                      <option key={entry.id} value={entry.id}>
                        {teamspaceEntryOptionLabel(entry)}
                      </option>
                    ))}
                  </select>
                </div>
              ) : null}

              <div className="grid gap-3 lg:grid-cols-[150px_120px_120px_minmax(220px,1fr)_auto] lg:items-end">
                <div className="space-y-2">
                  <label className="text-sm font-medium" htmlFor="ticket-session-day">
                    Datum
                  </label>
                  <Input
                    id="ticket-session-day"
                    type="date"
                    value={ticketSession.day}
                    onChange={(event) => setTicketSession({ ...ticketSession, day: event.currentTarget.value })}
                    required
                  />
                </div>
                <div className="space-y-2">
                  <label className="text-sm font-medium" htmlFor="ticket-session-start">
                    Von
                  </label>
                  <Input
                    id="ticket-session-start"
                    type="time"
                    value={ticketSession.startTime}
                    onChange={(event) => setTicketSession({ ...ticketSession, startTime: event.currentTarget.value })}
                    required
                  />
                </div>
                <div className="space-y-2">
                  <label className="text-sm font-medium" htmlFor="ticket-session-end">
                    Bis
                  </label>
                  <Input
                    id="ticket-session-end"
                    type="time"
                    value={ticketSession.endTime}
                    onChange={(event) => setTicketSession({ ...ticketSession, endTime: event.currentTarget.value })}
                    required
                  />
                </div>
                <div className="space-y-2">
                  <label className="text-sm font-medium" htmlFor="ticket-session-activity">
                    Tätigkeit
                  </label>
                  <Textarea
                    id="ticket-session-activity"
                    className="min-h-20"
                    value={ticketSession.activity}
                    onChange={(event) => setTicketSession({ ...ticketSession, activity: event.currentTarget.value })}
                    required
                  />
                </div>
                <Button type="submit" disabled={savingTicketSession}>
                  <Save className="size-4" />
                  {savingTicketSession ? "Speichert..." : "Nachtragen"}
                </Button>
              </div>
            </form>
          </CardContent>
        </Card>
      )}

      
      {data && data.openCount > 0 ? (
        <p className="text-sm text-muted-foreground">
          Noch {data.openCount} Session(s) ohne Auswahl. Erst wenn im Monat keine Sessions mehr offen sind, kann der Monat abgeschlossen werden.
        </p>
      ) : null}

      <Dialog open={Boolean(teamspacePreparation)} onOpenChange={(open) => !open && setTeamspacePreparation(null)}>
        <DialogContent className="max-h-[calc(100dvh-2rem)] w-[calc(100vw-2rem)] overflow-y-auto p-5 sm:max-w-2xl">
          <DialogHeader className="pr-8">
            <DialogTitle>TS Aufbereitung</DialogTitle>
            <DialogDescription>{teamspacePreparation?.label ?? "Sessiontätigkeiten des Tages"}</DialogDescription>
          </DialogHeader>
          <div className="space-y-4">
            <Textarea
              className="min-h-80 resize-y font-mono text-sm"
              value={teamspacePreparation?.text ?? ""}
              onChange={(event) =>
                setTeamspacePreparation((current) =>
                  current
                    ? {
                        ...current,
                        text: event.currentTarget.value
                      }
                    : current
                )
              }
            />
            <div className="flex flex-col-reverse gap-2 sm:flex-row sm:justify-end">
              <Button type="button" variant="secondary" onClick={() => setTeamspacePreparation(null)}>
                Schließen
              </Button>
              <Button type="button" disabled={!teamspacePreparation?.text.trim()} onClick={() => void copyTeamspacePreparation()}>
                <Copy className="size-4" />
                Kopieren
              </Button>
            </div>
          </div>
        </DialogContent>
      </Dialog>

      <Dialog open={Boolean(pendingProjectDelete)} onOpenChange={(open) => !open && void keepEmptyProject()}>
        <DialogContent className="sm:max-w-md">
          <DialogHeader>
            <DialogTitle>Keine Sessions mehr vorhanden</DialogTitle>
            <DialogDescription>Projekt löschen?</DialogDescription>
          </DialogHeader>
          <div className="flex flex-col-reverse gap-2 sm:flex-row sm:justify-end">
            <Button type="button" variant="secondary" disabled={deletingEmptyProject} onClick={() => void keepEmptyProject()}>
              Projekt behalten
            </Button>
            <Button type="button" variant="destructive" disabled={deletingEmptyProject} onClick={() => void deleteEmptyProject()}>
              <Trash2 className="size-4" />
              {deletingEmptyProject ? "Löscht..." : "Projekt löschen"}
            </Button>
          </div>
        </DialogContent>
      </Dialog>

      <Dialog open={Boolean(editingSession)} onOpenChange={(open) => !open && setEditingSession(null)}>
        <DialogContent className="max-h-[calc(100dvh-2rem)] w-[calc(100vw-2rem)] overflow-y-auto p-5 sm:max-w-2xl">
          <DialogHeader className="pr-8">
            <DialogTitle>Session bearbeiten</DialogTitle>
            <DialogDescription>Beginn, Ende, Tätigkeit und Stammdaten dieses Eintrags nachträglich korrigieren.</DialogDescription>
          </DialogHeader>
          <form className="space-y-4 overflow-x-hidden" onSubmit={saveSessionData}>
            <div className="grid gap-3 sm:grid-cols-3">
              <div className="space-y-2">
                <label className="text-sm font-medium" htmlFor="session-day">Datum</label>
                <Input
                  id="session-day"
                  type="date"
                  value={editSessionDay}
                  onChange={(event) => setEditSessionDay(event.currentTarget.value)}
                  required
                />
              </div>
              <div className="space-y-2">
                <label className="text-sm font-medium" htmlFor="session-start-time">Von</label>
                <Input
                  id="session-start-time"
                  type="time"
                  value={editSessionStartTime}
                  onChange={(event) => setEditSessionStartTime(event.currentTarget.value)}
                  required
                />
              </div>
              <div className="space-y-2">
                <label className="text-sm font-medium" htmlFor="session-end-time">Bis</label>
                <Input
                  id="session-end-time"
                  type="time"
                  value={editSessionEndTime}
                  onChange={(event) => setEditSessionEndTime(event.currentTarget.value)}
                  required
                />
              </div>
            </div>
            <div className="space-y-2">
              <label className="text-sm font-medium" htmlFor="session-organization">Organisation</label>
              {editingSession?.customer_name && !editingSession.organization_id ? (
                <p className="text-xs text-muted-foreground">Bisheriger Freitext: {editingSession.customer_name}</p>
              ) : null}
              <OrganizationSelect
                value={editSessionOrganizationId}
                selectedName={editSessionOrganizationName}
                onChange={(organization) => {
                  setEditSessionOrganizationId(organization.id);
                  setEditSessionOrganizationName(organization.name);
                }}
                required
              />
            </div>
            <div className="space-y-2">
              <label className="text-sm font-medium" htmlFor="session-activity">Tätigkeit</label>
              <Textarea
                id="session-activity"
                className="min-h-24 resize-y"
                value={editSessionActivity}
                onChange={(event) => setEditSessionActivity(event.currentTarget.value)}
                required
              />
            </div>
            <div className="space-y-2">
              <label className="text-sm font-medium" htmlFor="session-work-type">Art</label>
              <select
                id="session-work-type"
                className="h-8 w-full rounded-lg border border-input bg-background px-2 text-sm focus-visible:outline-none focus-visible:ring-3 focus-visible:ring-ring/50"
                value={editSessionWorkType}
                disabled={Boolean(editingSession?.recurring_billing_id)}
                onChange={(event) => setEditSessionWorkType(event.currentTarget.value as WorkType)}
              >
                <option value="support">Support</option>
                <option value="consulting">Consulting</option>
              </select>
            </div>
            {editSessionWorkType === "consulting" && requiresProjectTeamspaceEntry ? (
              <div className="space-y-2">
                <label className="text-sm font-medium" htmlFor="session-teamspace-entry">Teamspace-Eintrag</label>
                <select
                  id="session-teamspace-entry"
                  className="h-8 w-full rounded-lg border border-input bg-background px-2 text-sm focus-visible:outline-none focus-visible:ring-3 focus-visible:ring-ring/50"
                  value={editSessionProjectTeamspaceEntryId}
                  onChange={(event) => setEditSessionProjectTeamspaceEntryId(event.currentTarget.value)}
                  required
                >
                  <option value="">Bitte wählen</option>
                  {projectEntries.map((entry) => (
                    <option key={entry.id} value={entry.id}>
                      {teamspaceEntryOptionLabel(entry)}
                    </option>
                  ))}
                </select>
              </div>
            ) : null}
            <div className="flex justify-end">
              <Button type="submit" disabled={savingSessionDetails}>
                <Save className="size-4" />
                {savingSessionDetails ? "Speichert..." : "Session speichern"}
              </Button>
            </div>
          </form>
        </DialogContent>
      </Dialog>
    </div>
  );
}