UMBRA/frontend/src/components/projects/ProjectDetail.tsx

import { useState, useMemo, useCallback } from 'react';
import { useMediaQuery, DESKTOP } from '@/hooks/useMediaQuery';
import { useParams, useNavigate } from 'react-router-dom';
import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query';
import { toast } from 'sonner';
import { format, isPast, parseISO } from 'date-fns';
import {
  DndContext,
  closestCenter,
  KeyboardSensor,
  PointerSensor,
  useSensor,
  useSensors,
  type DragEndEvent,
} from '@dnd-kit/core';
import {
  SortableContext,
  verticalListSortingStrategy,
  useSortable,
  arrayMove,
} from '@dnd-kit/sortable';
import { CSS } from '@dnd-kit/utilities';
import {
  ArrowLeft, Plus, Trash2, ListChecks, Pencil, Pin,
  Calendar, CheckCircle2, PlayCircle, AlertTriangle,
  List, Columns3, ArrowUpDown, Users, Eye,
} from 'lucide-react';
import api from '@/lib/api';
import type { Project, ProjectTask, ProjectMember } from '@/types';
import { Button } from '@/components/ui/button';
import { Badge } from '@/components/ui/badge';
import { Card, CardContent } from '@/components/ui/card';
import { Select } from '@/components/ui/select';
import { ListSkeleton } from '@/components/ui/skeleton';
import { EmptyState } from '@/components/ui/empty-state';
import { useSettings } from '@/hooks/useSettings';
import { useDeltaPoll } from '@/hooks/useDeltaPoll';
import TaskRow from './TaskRow';
import TaskDetailPanel from './TaskDetailPanel';
import KanbanBoard from './KanbanBoard';
import TaskForm from './TaskForm';
import ProjectForm from './ProjectForm';
import { ProjectShareSheet } from './ProjectShareSheet';
import { statusColors, statusLabels } from './constants';
import MobileDetailOverlay from '@/components/shared/MobileDetailOverlay';

type SortMode = 'manual' | 'priority' | 'due_date';
type ViewMode = 'list' | 'kanban';

const PRIORITY_ORDER: Record<string, number> = { high: 0, medium: 1, low: 2, none: 3 };

function SortableTaskRow({
  task,
  isSelected,
  isExpanded,
  showDragHandle,
  onSelect,
  onToggleExpand,
  onToggleStatus,
  togglePending,
}: {
  task: ProjectTask;
  isSelected: boolean;
  isExpanded: boolean;
  showDragHandle: boolean;
  onSelect: () => void;
  onToggleExpand: () => void;
  onToggleStatus: () => void;
  togglePending: boolean;
}) {
  const {
    attributes,
    listeners,
    setNodeRef,
    transform,
    transition,
    isDragging,
  } = useSortable({ id: task.id });

  const style = {
    transform: CSS.Transform.toString(transform),
    transition,
    opacity: isDragging ? 0.5 : 1,
  };

  return (
    <div ref={setNodeRef} style={style} {...attributes}>
      <TaskRow
        task={task}
        isSelected={isSelected}
        isExpanded={isExpanded}
        showDragHandle={showDragHandle}
        onSelect={onSelect}
        onToggleExpand={onToggleExpand}
        onToggleStatus={onToggleStatus}
        togglePending={togglePending}
        dragHandleProps={listeners}
      />
    </div>
  );
}

export default function ProjectDetail() {
  const { id } = useParams();
  const navigate = useNavigate();
  const queryClient = useQueryClient();

  const [showTaskForm, setShowTaskForm] = useState(false);
  const [showProjectForm, setShowProjectForm] = useState(false);
  const [editingTask, setEditingTask] = useState<ProjectTask | null>(null);
  const [subtaskParentId, setSubtaskParentId] = useState<number | null>(null);
  const [expandedTasks, setExpandedTasks] = useState<Set<number>>(new Set());
  const [selectedTaskId, setSelectedTaskId] = useState<number | null>(null);
  const [kanbanParentTaskId, setKanbanParentTaskId] = useState<number | null>(null);
  const [sortMode, setSortMode] = useState<SortMode>('manual');
  const [viewMode, setViewMode] = useState<ViewMode>('list');
  const [showShareSheet, setShowShareSheet] = useState(false);
  const { settings } = useSettings();
  const currentUserId = settings?.user_id ?? 0;

  const sensors = useSensors(
    useSensor(PointerSensor, { activationConstraint: { distance: 5 } }),
    useSensor(KeyboardSensor)
  );

  const toggleExpand = (taskId: number) => {
    setExpandedTasks((prev) => {
      const next = new Set(prev);
      if (next.has(taskId)) next.delete(taskId);
      else next.add(taskId);
      return next;
    });
  };

  const { data: project, isLoading } = useQuery({
    queryKey: ['projects', id],
    queryFn: async () => {
      const { data } = await api.get<Project>(`/projects/${id}`);
      return data;
    },
  });

  // Permission derivation
  const isOwner = project ? project.user_id === currentUserId : true;
  const isShared = project ? project.user_id !== currentUserId : false;
  // For now, if they can see the project but don't own it, check if they can edit
  // The backend enforces actual permissions — this is just UI gating
  const canEdit = isOwner; // Members with create_modify can also edit tasks (handled per-task)
  const canManageProject = isOwner;

  // Delta polling for real-time sync on shared projects
  const pollKey = useMemo(() => ['projects', id], [id]);
  useDeltaPoll(
    id ? `/projects/${id}/poll` : null,
    pollKey,
    5000,
  );

  // Fetch members for shared projects
  const { data: members = [] } = useQuery<ProjectMember[]>({
    queryKey: ['project-members', id],
    queryFn: async () => {
      const { data } = await api.get(`/projects/${id}/members`);
      return data;
    },
    enabled: !!id,
  });
  const acceptedMembers = members.filter((m) => m.status === 'accepted');

  const toggleTaskMutation = useMutation({
    mutationFn: async ({ taskId, status }: { taskId: number; status: string }) => {
      const newStatus = status === 'completed' ? 'pending' : 'completed';
      const { data } = await api.put(`/projects/${id}/tasks/${taskId}`, { status: newStatus });
      return data;
    },
    onSuccess: () => {
      queryClient.invalidateQueries({ queryKey: ['projects', id] });
    },
    onError: () => {
      toast.error('Failed to update task');
    },
  });

  const deleteTaskMutation = useMutation({
    mutationFn: async (taskId: number) => {
      await api.delete(`/projects/${id}/tasks/${taskId}`);
    },
    onSuccess: () => {
      queryClient.invalidateQueries({ queryKey: ['projects', id] });
      toast.success('Task deleted');
      setSelectedTaskId(null);
    },
  });

  const deleteProjectMutation = useMutation({
    mutationFn: async () => {
      await api.delete(`/projects/${id}`);
    },
    onSuccess: () => {
      queryClient.invalidateQueries({ queryKey: ['projects'] });
      toast.success('Project deleted');
      navigate('/projects');
    },
    onError: () => {
      toast.error('Failed to delete project');
    },
  });

  const toggleTrackMutation = useMutation({
    mutationFn: async () => {
      const { data } = await api.put(`/projects/${id}`, { is_tracked: !project?.is_tracked });
      return data;
    },
    onSuccess: () => {
      queryClient.invalidateQueries({ queryKey: ['projects'] });
      queryClient.invalidateQueries({ queryKey: ['projects', id] });
      queryClient.invalidateQueries({ queryKey: ['tracked-tasks'] });
      toast.success(project?.is_tracked ? 'Project untracked' : 'Project tracked');
    },
    onError: () => {
      toast.error('Failed to update tracking');
    },
  });

  const reorderMutation = useMutation({
    mutationFn: async (items: { id: number; sort_order: number }[]) => {
      await api.put(`/projects/${id}/tasks/reorder`, items);
    },
    onSuccess: () => {
      queryClient.invalidateQueries({ queryKey: ['projects', id] });
    },
  });

  const updateTaskStatusMutation = useMutation({
    mutationFn: async ({ taskId, status }: { taskId: number; status: string }) => {
      const { data } = await api.put(`/projects/${id}/tasks/${taskId}`, { status });
      return data;
    },
    onSuccess: () => {
      queryClient.invalidateQueries({ queryKey: ['projects', id] });
    },
    onError: () => {
      toast.error('Failed to update task status');
    },
  });

  const allTasks = project?.tasks || [];
  const topLevelTasks = useMemo(
    () => allTasks.filter((t) => !t.parent_task_id),
    [allTasks]
  );

  const sortSubtasks = useCallback(
    (subtasks: ProjectTask[]): ProjectTask[] => {
      if (sortMode === 'manual') return subtasks;
      const sorted = [...subtasks];
      if (sortMode === 'priority') {
        sorted.sort((a, b) => (PRIORITY_ORDER[a.priority] ?? 3) - (PRIORITY_ORDER[b.priority] ?? 3));
      } else if (sortMode === 'due_date') {
        sorted.sort((a, b) => {
          if (!a.due_date && !b.due_date) return 0;
          if (!a.due_date) return 1;
          if (!b.due_date) return -1;
          return a.due_date.localeCompare(b.due_date);
        });
      }
      return sorted;
    },
    [sortMode]
  );

  const sortedTasks = useMemo(() => {
    const tasks = [...topLevelTasks].map((t) => ({
      ...t,
      subtasks: sortSubtasks(t.subtasks || []),
    }));
    switch (sortMode) {
      case 'priority':
        return tasks.sort(
          (a, b) => (PRIORITY_ORDER[a.priority] ?? 3) - (PRIORITY_ORDER[b.priority] ?? 3)
        );
      case 'due_date':
        return tasks.sort((a, b) => {
          if (!a.due_date && !b.due_date) return 0;
          if (!a.due_date) return 1;
          if (!b.due_date) return -1;
          return a.due_date.localeCompare(b.due_date);
        });
      case 'manual':
      default:
        return tasks.sort((a, b) => a.sort_order - b.sort_order);
    }
  }, [topLevelTasks, sortMode, sortSubtasks]);

  const isDesktop = useMediaQuery(DESKTOP);

  const selectedTask = useMemo(() => {
    if (!selectedTaskId) return null;
    // Search top-level and subtasks
    for (const task of allTasks) {
      if (task.id === selectedTaskId) return task;
      if (task.subtasks) {
        const sub = task.subtasks.find((s) => s.id === selectedTaskId);
        if (sub) return sub;
      }
    }
    return null;
  }, [selectedTaskId, allTasks]);

  const kanbanParentTask = useMemo(() => {
    if (!kanbanParentTaskId) return null;
    return topLevelTasks.find((t) => t.id === kanbanParentTaskId) || null;
  }, [kanbanParentTaskId, topLevelTasks]);

  const handleKanbanSelectTask = useCallback(
    (taskId: number) => {
      setSelectedTaskId(taskId);
      // Only enter subtask view when clicking a top-level task with subtasks
      // and we're not already in subtask view
      if (!kanbanParentTaskId) {
        const task = topLevelTasks.find((t) => t.id === taskId);
        if (task && task.subtasks && task.subtasks.length > 0) {
          setKanbanParentTaskId(taskId);
        }
      }
    },
    [kanbanParentTaskId, topLevelTasks]
  );

  const handleBackToAllTasks = useCallback(() => {
    setKanbanParentTaskId(null);
    setSelectedTaskId(null);
  }, []);

  const handleDragEnd = useCallback(
    (event: DragEndEvent) => {
      const { active, over } = event;
      if (!over || active.id === over.id) return;

      const oldIndex = sortedTasks.findIndex((t) => t.id === active.id);
      const newIndex = sortedTasks.findIndex((t) => t.id === over.id);
      const reordered = arrayMove(sortedTasks, oldIndex, newIndex);

      const items = reordered.map((task, index) => ({
        id: task.id,
        sort_order: index,
      }));

      // Optimistic update
      queryClient.setQueryData(['projects', id], (old: Project | undefined) => {
        if (!old) return old;
        const updated = { ...old, tasks: [...old.tasks] };
        for (const item of items) {
          const t = updated.tasks.find((tt) => tt.id === item.id);
          if (t) t.sort_order = item.sort_order;
        }
        return updated;
      });

      reorderMutation.mutate(items);
    },
    [sortedTasks, id, queryClient, reorderMutation]
  );

  const openTaskForm = (task: ProjectTask | null, parentId: number | null) => {
    setEditingTask(task);
    setSubtaskParentId(parentId);
    setShowTaskForm(true);
  };

  const closeTaskForm = () => {
    setShowTaskForm(false);
    setEditingTask(null);
    setSubtaskParentId(null);
  };

  const handleDeleteTask = (taskId: number) => {
    if (!window.confirm('Delete this task and all its subtasks?')) return;
    deleteTaskMutation.mutate(taskId);
  };

  if (isLoading) {
    return (
      <div className="flex flex-col h-full animate-fade-in">
        <div className="border-b bg-card px-4 md:px-6 min-h-[4rem] flex items-center gap-2 md:gap-4 flex-wrap py-2 md:py-0 md:h-16 md:flex-nowrap shrink-0">
          <Button variant="ghost" size="icon" onClick={() => navigate('/projects')}>
            <ArrowLeft className="h-5 w-5" />
          </Button>
          <h1 className="font-heading text-xl md:text-2xl font-bold tracking-tight flex-1">Loading...</h1>
        </div>
        <div className="flex-1 overflow-y-auto px-4 md:px-6 py-5">
          <ListSkeleton rows={4} />
        </div>
      </div>
    );
  }

  if (!project) {
    return <div className="p-6 text-center text-muted-foreground">Project not found</div>;
  }

  const completedTasks = allTasks.filter((t) => t.status === 'completed').length;
  const inProgressTasks = allTasks.filter((t) => t.status === 'in_progress').length;
  const overdueTasks = allTasks.filter(
    (t) => t.due_date && t.status !== 'completed' && isPast(parseISO(t.due_date))
  ).length;
  const totalTasks = allTasks.length;
  const progressPercent = totalTasks > 0 ? (completedTasks / totalTasks) * 100 : 0;
  const isProjectOverdue =
    project.due_date && project.status !== 'completed' && isPast(parseISO(project.due_date));

  return (
    <div className="flex flex-col h-full animate-fade-in">
      {/* Header */}
      <div className="border-b bg-card px-4 md:px-6 h-16 flex items-center gap-2 md:gap-4 shrink-0">
        <Button variant="ghost" size="icon" onClick={() => navigate('/projects')}>
          <ArrowLeft className="h-5 w-5" />
        </Button>
        <h1 className="font-heading text-xl md:text-2xl font-bold tracking-tight flex-1 truncate min-w-0">
          {project.name}
        </h1>
        <Badge className={`shrink-0 hidden sm:inline-flex ${statusColors[project.status]}`}>
          {statusLabels[project.status]}
        </Badge>
        {/* Permission badge for non-owners */}
        {isShared && (
          <Badge className="shrink-0 bg-blue-500/10 text-blue-400 border-0">
            {acceptedMembers.find((m) => m.user_id === currentUserId)?.permission === 'create_modify' ? 'Editor' : 'Viewer'}
          </Badge>
        )}
        {canManageProject && (
          <Button
            variant="ghost"
            size="icon"
            onClick={() => toggleTrackMutation.mutate()}
            disabled={toggleTrackMutation.isPending}
            className={`shrink-0 ${project.is_tracked ? 'text-accent' : 'text-muted-foreground'}`}
            title={project.is_tracked ? 'Untrack project' : 'Track project'}
          >
            <Pin className={`h-4 w-4 ${project.is_tracked ? 'fill-current' : ''}`} />
          </Button>
        )}
        <Button
          variant="ghost"
          size="icon"
          className="shrink-0 text-muted-foreground relative"
          onClick={() => setShowShareSheet(true)}
          title="Project members"
        >
          <Users className="h-4 w-4" />
          {acceptedMembers.length > 0 && (
            <span className="absolute -top-0.5 -right-0.5 w-4 h-4 rounded-full bg-accent text-[9px] font-bold flex items-center justify-center text-background">
              {acceptedMembers.length}
            </span>
          )}
        </Button>
        {canManageProject && (
          <Button variant="outline" size="sm" className="shrink-0" onClick={() => setShowProjectForm(true)}>
            <Pencil className="h-3.5 w-3.5 md:mr-2" /><span className="hidden md:inline">Edit</span>
          </Button>
        )}
        {canManageProject && (
          <Button
            variant="ghost"
            size="sm"
            className="shrink-0 text-destructive hover:bg-destructive/10"
            onClick={() => {
              if (!window.confirm('Delete this project and all its tasks?')) return;
              deleteProjectMutation.mutate();
            }}
            disabled={deleteProjectMutation.isPending}
          >
            <Trash2 className="h-3.5 w-3.5 md:mr-2" /><span className="hidden md:inline">Delete</span>
          </Button>
        )}
      </div>

      {/* Content area */}
      <div className="flex-1 overflow-hidden flex flex-col">
        {/* Summary section - scrolls with left panel on small, fixed on large */}
        <div className="px-4 md:px-6 py-5 space-y-5 shrink-0 overflow-y-auto max-h-[50vh] lg:max-h-none lg:overflow-visible">
          {/* Description */}
          {project.description && (
            <p className="text-sm text-muted-foreground">{project.description}</p>
          )}

          {/* Project Summary Card */}
          <Card className="bg-gradient-to-br from-accent/[0.03] to-transparent">
            <CardContent className="p-5">
              <div className="flex flex-col sm:flex-row sm:items-center gap-4 sm:gap-6">
                <div className="flex-1">
                  <div className="flex items-baseline justify-between mb-2">
                    <span className="text-sm text-muted-foreground">Overall Progress</span>
                    <span className="font-heading text-lg font-bold tabular-nums">
                      {Math.round(progressPercent)}%
                    </span>
                  </div>
                  <div className="h-2.5 bg-secondary rounded-full overflow-hidden">
                    <div
                      className="h-full bg-accent rounded-full transition-all duration-300"
                      style={{ width: `${progressPercent}%` }}
                    />
                  </div>
                  <p className="text-xs text-muted-foreground mt-1.5 tabular-nums">
                    {completedTasks} of {totalTasks} tasks completed
                  </p>
                </div>
                <div className="hidden sm:block w-px h-16 bg-border" />
                <div className="flex items-center gap-5">
                  <div className="text-center">
                    <div className="p-1.5 rounded-md bg-blue-500/10 mx-auto w-fit mb-1">
                      <ListChecks className="h-4 w-4 text-blue-400" />
                    </div>
                    <p className="font-heading text-lg font-bold tabular-nums">{totalTasks}</p>
                    <p className="text-[10px] tracking-wider uppercase text-muted-foreground">Total</p>
                  </div>
                  <div className="text-center">
                    <div className="p-1.5 rounded-md bg-purple-500/10 mx-auto w-fit mb-1">
                      <PlayCircle className="h-4 w-4 text-purple-400" />
                    </div>
                    <p className="font-heading text-lg font-bold tabular-nums">{inProgressTasks}</p>
                    <p className="text-[10px] tracking-wider uppercase text-muted-foreground">Active</p>
                  </div>
                  <div className="text-center">
                    <div className="p-1.5 rounded-md bg-green-500/10 mx-auto w-fit mb-1">
                      <CheckCircle2 className="h-4 w-4 text-green-400" />
                    </div>
                    <p className="font-heading text-lg font-bold tabular-nums">{completedTasks}</p>
                    <p className="text-[10px] tracking-wider uppercase text-muted-foreground">Done</p>
                  </div>
                  {overdueTasks > 0 && (
                    <div className="text-center">
                      <div className="p-1.5 rounded-md bg-red-500/10 mx-auto w-fit mb-1">
                        <AlertTriangle className="h-4 w-4 text-red-400" />
                      </div>
                      <p className="font-heading text-lg font-bold tabular-nums text-red-400">{overdueTasks}</p>
                      <p className="text-[10px] tracking-wider uppercase text-muted-foreground">Overdue</p>
                    </div>
                  )}
                </div>
              </div>
              {project.due_date && (
                <div className={`flex items-center gap-2 text-sm mt-4 pt-3 border-t border-border ${isProjectOverdue ? 'text-red-400' : 'text-muted-foreground'}`}>
                  <Calendar className="h-4 w-4" />
                  Due {format(parseISO(project.due_date), 'MMM d, yyyy')}
                  {isProjectOverdue && <span className="text-xs font-medium">(Overdue)</span>}
                </div>
              )}
            </CardContent>
          </Card>
        </div>

        {/* Read-only banner for viewers */}
        {isShared && !canEdit && (
          <div className="mx-4 md:mx-6 mb-3 px-3 py-2 rounded-md bg-secondary/50 border border-border flex items-center gap-2">
            <Eye className="h-3.5 w-3.5 text-muted-foreground shrink-0" />
            <span className="text-xs text-muted-foreground">You have view-only access to this project</span>
          </div>
        )}

        {/* Task list header + view controls */}
        <div className="px-4 md:px-6 pb-3 flex items-center justify-between flex-wrap gap-2 shrink-0">
          <h2 className="font-heading text-lg font-semibold">Tasks</h2>
          <div className="flex items-center gap-2">
            {/* View toggle */}
            <div className="flex items-center rounded-md border border-border overflow-hidden">
              <button
                onClick={() => { setViewMode('list'); setKanbanParentTaskId(null); }}
                className={`px-2.5 py-1.5 transition-colors ${
                  viewMode === 'list'
                    ? 'bg-accent/15 text-accent'
                    : 'text-muted-foreground hover:text-foreground hover:bg-card-elevated'
                }`}
              >
                <List className="h-3.5 w-3.5" />
              </button>
              <button
                onClick={() => setViewMode('kanban')}
                className={`px-2.5 py-1.5 transition-colors ${
                  viewMode === 'kanban'
                    ? 'bg-accent/15 text-accent'
                    : 'text-muted-foreground hover:text-foreground hover:bg-card-elevated'
                }`}
              >
                <Columns3 className="h-3.5 w-3.5" />
              </button>
            </div>

            {/* Sort dropdown (list view only) */}
            {viewMode === 'list' && (
              <div className="flex items-center gap-1.5">
                <ArrowUpDown className="h-3.5 w-3.5 text-muted-foreground" />
                <Select
                  value={sortMode}
                  onChange={(e) => setSortMode(e.target.value as SortMode)}
                  className="h-8 text-xs w-auto min-w-[100px]"
                >
                  <option value="manual">Manual</option>
                  <option value="priority">Priority</option>
                  <option value="due_date">Due Date</option>
                </Select>
              </div>
            )}

            {(isOwner || acceptedMembers.find((m) => m.user_id === currentUserId)?.permission === 'create_modify') && (
              <Button size="sm" onClick={() => openTaskForm(null, null)}>
                <Plus className="mr-2 h-3.5 w-3.5" />
                Add Task
              </Button>
            )}
          </div>
        </div>

        {/* Main content: task list/kanban + detail panel */}
        <div className="flex-1 overflow-hidden flex">
          {/* Left panel: task list or kanban */}
          <div className={`overflow-y-auto transition-all duration-300 ease-[cubic-bezier(0.16,1,0.3,1)] ${selectedTaskId ? 'w-full lg:w-[55%]' : 'w-full'}`}>
            <div className="px-4 md:px-6 pb-6">
              {topLevelTasks.length === 0 ? (
                <EmptyState
                  icon={ListChecks}
                  title="No tasks yet"
                  description="Break this project down into tasks to track your progress."
                  actionLabel="Add Task"
                  onAction={() => openTaskForm(null, null)}
                />
              ) : viewMode === 'kanban' ? (
                <KanbanBoard
                  tasks={topLevelTasks}
                  selectedTaskId={selectedTaskId}
                  kanbanParentTask={kanbanParentTask}
                  onSelectTask={handleKanbanSelectTask}
                  onStatusChange={(taskId, status) =>
                    updateTaskStatusMutation.mutate({ taskId, status })
                  }
                  onBackToAllTasks={handleBackToAllTasks}
                />
              ) : (
                <DndContext
                  sensors={sensors}
                  collisionDetection={closestCenter}
                  onDragEnd={handleDragEnd}
                >
                  <SortableContext
                    items={sortedTasks.map((t) => t.id)}
                    strategy={verticalListSortingStrategy}
                    disabled={sortMode !== 'manual'}
                  >
                    <div className="space-y-1">
                      {sortedTasks.map((task) => {
                        const isExpanded = expandedTasks.has(task.id);
                        const hasSubtasks = task.subtasks && task.subtasks.length > 0;

                        return (
                          <div key={task.id}>
                            <SortableTaskRow
                              task={task}
                              isSelected={selectedTaskId === task.id}
                              isExpanded={isExpanded}
                              showDragHandle={sortMode === 'manual'}
                              onSelect={() => setSelectedTaskId(task.id)}
                              onToggleExpand={() => toggleExpand(task.id)}
                              onToggleStatus={() =>
                                toggleTaskMutation.mutate({
                                  taskId: task.id,
                                  status: task.status,
                                })
                              }
                              togglePending={toggleTaskMutation.isPending}
                            />
                            {/* Expanded subtasks */}
                            {isExpanded && hasSubtasks && (
                              <div className="ml-5 sm:ml-10 mt-0.5 space-y-0.5">
                                {task.subtasks.map((subtask) => (
                                  <TaskRow
                                    key={subtask.id}
                                    task={subtask}
                                    isSelected={selectedTaskId === subtask.id}
                                    isExpanded={false}
                                    showDragHandle={false}
                                    onSelect={() => setSelectedTaskId(subtask.id)}
                                    onToggleExpand={() => {}}
                                    onToggleStatus={() =>
                                      toggleTaskMutation.mutate({
                                        taskId: subtask.id,
                                        status: subtask.status,
                                      })
                                    }
                                    togglePending={toggleTaskMutation.isPending}
                                  />
                                ))}
                              </div>
                            )}
                          </div>
                        );
                      })}
                    </div>
                  </SortableContext>
                </DndContext>
              )}
            </div>
          </div>

          {/* Right panel: task detail (desktop only) */}
          {selectedTaskId && isDesktop && (
            <div
              className="overflow-hidden transition-all duration-300 ease-[cubic-bezier(0.16,1,0.3,1)] border-l border-border bg-card flex w-[45%]"
            >
              <div className="flex-1 overflow-hidden min-w-[360px]">
                <TaskDetailPanel
                  task={selectedTask}
                  projectId={parseInt(id!)}
                  onDelete={handleDeleteTask}
                  onAddSubtask={(parentId) => openTaskForm(null, parentId)}
                  onClose={() => setSelectedTaskId(null)}
                  onSelectTask={setSelectedTaskId}
                />
              </div>
            </div>
          )}
        </div>
      </div>

      {/* Mobile: show detail panel as overlay when task selected on small screens */}
      {selectedTaskId && selectedTask && !isDesktop && (
        <MobileDetailOverlay open={true} onClose={() => setSelectedTaskId(null)}>
          <div className="flex items-center justify-between px-4 py-3 border-b border-border">
            <span className="text-sm font-medium text-muted-foreground">Task Details</span>
            <Button
              variant="ghost"
              size="sm"
              onClick={() => setSelectedTaskId(null)}
            >
              Close
            </Button>
          </div>
          <div className="h-[calc(100%-49px)]">
            <TaskDetailPanel
              task={selectedTask}
              projectId={parseInt(id!)}
              onDelete={handleDeleteTask}
              onAddSubtask={(parentId) => openTaskForm(null, parentId)}
              onClose={() => setSelectedTaskId(null)}
              onSelectTask={setSelectedTaskId}
            />
          </div>
        </MobileDetailOverlay>
      )}

      {showTaskForm && (
        <TaskForm
          projectId={parseInt(id!)}
          task={editingTask}
          parentTaskId={subtaskParentId}
          defaultDueDate={
            subtaskParentId
              ? allTasks.find((t) => t.id === subtaskParentId)?.due_date
              : project?.due_date
          }
          onClose={closeTaskForm}
        />
      )}

      {showProjectForm && (
        <ProjectForm
          project={project}
          onClose={() => setShowProjectForm(false)}
        />
      )}

      <ProjectShareSheet
        open={showShareSheet}
        onOpenChange={setShowShareSheet}
        projectId={parseInt(id!)}
        isOwner={isOwner}
        ownerName={settings?.preferred_name || 'Owner'}
      />
    </div>
  );
}