import { useState, useEffect } from 'react';
import { useTranslation } from 'react-i18next';
import { Toaster } from "@/components/ui/toaster";
import { TooltipProvider } from "@/components/ui/tooltip";
import { Button } from "@/components/ui/button";
import {
  AlertDialog,
  AlertDialogAction,
  AlertDialogCancel,
  AlertDialogContent,
  AlertDialogDescription,
  AlertDialogFooter,
  AlertDialogHeader,
  AlertDialogTitle,
} from "@/components/ui/alert-dialog";

import { Switch, Route, useLocation } from "wouter";

// ADHD Mode Components
import {
  ADHDModeProvider,
  useADHDMode,
  BreakReminderProvider,
  BreakReminderOverlay,
  EnergyCheckIn,
  HyperfocusGuard,
  EncouragementToast
} from '@/components/adhd';

// Components
import TaskCreationModal from './components/TaskCreationModal';
import TaskDetailsModal from './components/TaskDetailsModal';
import TasksWithCalendar from './components/TasksWithCalendar';
import FocusMode from './components/FocusMode';
import CalendarView from './components/CalendarView';
import KanbanBoard from './components/KanbanBoard';
import ProjectTemplate from './components/ProjectTemplate';
import WeekListView from './components/WeekListView';
import Settings from './pages/settings';
import AchievementsPage from './pages/AchievementsPage';
import UnscheduledTasksPage from './pages/UnscheduledTasksPage';
import { Task, Label } from '@shared/schema';
import { useTimer } from './hooks/useTimer';
import { Plus } from 'lucide-react';
import { SidebarProvider, SidebarInset, SidebarTrigger } from "@/components/ui/sidebar"
import { AppSidebar } from "./components/AppSidebar"
import { useNotifications } from './hooks/use-notifications';
import { useToast } from "@/hooks/use-toast";
import { CommandPalette } from './components/CommandPalette';
import PomodoroOverlay from './components/PomodoroOverlay';
import AuthPage from "@/pages/AuthPage";

import LeaderboardPage from "@/pages/LeaderboardPage";
import SetupWizard from "@/pages/SetupWizard";
import AdminUserManagement from "@/pages/AdminUserManagement";
import AdminSettings from "@/pages/AdminSettings";
import NotFound from "@/pages/not-found";
// import { AiChat } from "@/components/AiChat";
import ForgotPasswordPage from "@/pages/ForgotPasswordPage";
import ResetPasswordPage from "@/pages/ResetPasswordPage";
import AiChatPage from "@/pages/AiChatPage";
import NotificationsPage from "@/pages/NotificationsPage";
import FocusRoutinePage from "@/pages/FocusRoutinePage";


import { useRoutineBlocker } from './components/RoutineBlocker';

import { useQuery, useQueryClient } from "@tanstack/react-query";
import { User } from "@shared/schema";
import { Loader2 } from "lucide-react";


import TimeTrackingPage from './pages/TimeTrackingPage';

// ADHD Pages
import QuickWinsPage from './pages/QuickWinsPage';
import SingleTaskPage from './pages/SingleTaskPage';
import BodyDoublingPage from './pages/BodyDoublingPage';
import ADHDDashboardPage from './pages/ADHDDashboardPage';

// Inner App component that uses ADHD hooks
function AppContent() {
  const { t } = useTranslation();
  const { toast } = useToast();
  const [, setLocation] = useLocation();
  const isBlocked = useRoutineBlocker();
  const { isEnabled: adhdEnabled, settings: adhdSettings } = useADHDMode();

  const [isCreateModalOpen, setIsCreateModalOpen] = useState(false);
  const [isTaskDetailsOpen, setIsTaskDetailsOpen] = useState(false);
  const [selectedTask, setSelectedTask] = useState<Task | null>(null);
  const [deleteTaskId, setDeleteTaskId] = useState<string | null>(null);
  const [showPomodoro, setShowPomodoro] = useState(false);
  const [activePomodoroTaskId, setActivePomodoroTaskId] = useState<string | null>(null);

  // Enable global notifications polling
  useNotifications({ poll: true });

  const queryClient = useQueryClient();

  const { data: user, isLoading: isLoadingUser } = useQuery<User>({
    queryKey: ["/api/user"],
    retry: false,
  });

  const { data: setupStatus } = useQuery<{ isSetup: boolean }>({
    queryKey: ['/api/setup/status'],
  });

  // Fetch tasks and labels using React Query
  const { data: tasksData } = useQuery<Task[]>({
    queryKey: ['/api/tasks'],
    enabled: !!user,
  });

  const tasks = (tasksData ?? []).map(task => ({
    ...task,
    dueDate: task.dueDate ? new Date(task.dueDate) : null
  }));

  const { data: labelsData } = useQuery<Label[]>({
    queryKey: ['/api/labels'],
    enabled: !!user,
  });
  const labels = labelsData ?? [];

  const handleCreateTask = async (newTask: Partial<Task>) => {
    try {
      const response = await fetch('/api/tasks', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({
          title: newTask.title || '',
          description: newTask.description || undefined,
          status: 'todo',
          priority: newTask.priority || 'medium',
          dueDate: newTask.dueDate || null, // Explicitly handled as nullable in schema
          timeTracked: 0,
          isTracking: false,
          projectId: newTask.projectId || undefined,
          notes: newTask.notes || undefined,
          labelId: newTask.labelId || undefined,
          energyLevel: newTask.energyLevel || 'medium',
          estimatedDuration: newTask.estimatedDuration || undefined
        })
      });

      if (!response.ok) throw new Error('Failed to create task');

      const createdTask: Task = await response.json();

      // Update cache optimistically or invalidation
      queryClient.setQueryData(['/api/tasks'], (old: Task[] = []) => {
        const normalizedTask = {
          ...createdTask,
          dueDate: createdTask.dueDate ? new Date(createdTask.dueDate) : null
        };
        return [...old, normalizedTask];
      });
      // Invalidate to be sure
      queryClient.invalidateQueries({ queryKey: ['/api/tasks'] });

      toast({
        title: t('task.created', 'Task Created'),
        description: t('task.createdDescription', '"{title}" has been added.', { title: createdTask.title }),
      });

    } catch (error) {
      console.error('Error creating task:', error);
      toast({
        title: t('error.createTask', 'Error'),
        description: t('error.createTaskDescription', 'Failed to create task. Please try again.'),
        variant: "destructive"
      });
    }
  };

  const handleTaskUpdate = async (taskId: string, updates: Partial<Task>) => {
    // Optimistic Update
    const previousTasks = queryClient.getQueryData<Task[]>(['/api/tasks']);

    queryClient.setQueryData(['/api/tasks'], (old: Task[] = []) =>
      old.map(task => task.id === taskId ? { ...task, ...updates } : task)
    );

    try {
      const response = await fetch(`/api/tasks/${taskId}`, {
        method: 'PATCH',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify(updates)
      });

      if (!response.ok) throw new Error('Failed to update task');

      const updatedTask: Task = await response.json();

      queryClient.setQueryData(['/api/tasks'], (old: Task[] = []) => uniqueTasks(old, updatedTask));

    } catch (error) {
      console.error('Error updating task:', error);
      // Rollback
      if (previousTasks) {
        queryClient.setQueryData(['/api/tasks'], previousTasks);
      }
    }
  };

  // Helper to merge updated task into array
  const uniqueTasks = (tasks: Task[], updated: Task) => {
    const normalized = { ...updated, dueDate: updated.dueDate ? new Date(updated.dueDate) : null };
    return tasks.map(t => t.id === updated.id ? normalized : t);
  };

  const handleCreateFromTemplate = (templateId: string, startDate: Date, projectName: string) => {
    console.log('Creating project from template:', { templateId, startDate, projectName });
    // Assuming this might create tasks, we should invalidate
    setTimeout(() => queryClient.invalidateQueries({ queryKey: ['/api/tasks'] }), 1000);
  };

  const { startTimer, stopTimer } = useTimer({
    tasks,
    onTaskUpdate: handleTaskUpdate
  });

  const handleStartPomodoro = (taskId: string) => {
    setActivePomodoroTaskId(taskId);
    setShowPomodoro(true);
    startTimer(taskId);
  };

  const handleTaskStatusChange = (taskId: string, newStatus: Task['status']) => {
    handleTaskUpdate(taskId, { status: newStatus });
  };

  const handleTaskDrop = (taskId: string, newDate: Date) => {
    handleTaskUpdate(taskId, { dueDate: newDate });
  };

  const handleTaskClick = (task: Task) => {
    setSelectedTask(task);
    setIsTaskDetailsOpen(true);
  };

  const handleTaskDetailsClose = () => {
    setIsTaskDetailsOpen(false);
    setSelectedTask(null);
  };

  const handleTaskDetailsSave = (updatedTask: Task) => {
    handleTaskUpdate(updatedTask.id, updatedTask);
  };

  const handleTaskDelete = async (taskId: string) => {
    setDeleteTaskId(taskId);
  };

  const confirmTaskDelete = async () => {
    if (!deleteTaskId) return;

    const previousTasks = queryClient.getQueryData<Task[]>(['/api/tasks']);
    const taskToDelete = tasks.find(task => task.id === deleteTaskId);

    // Optimistic delete
    queryClient.setQueryData(['/api/tasks'], (old: Task[] = []) =>
      old.filter(task => task.id !== deleteTaskId)
    );

    if (selectedTask?.id === deleteTaskId) {
      handleTaskDetailsClose();
    }
    setDeleteTaskId(null);

    try {
      const response = await fetch(`/api/tasks/${deleteTaskId}`, { method: 'DELETE' });
      if (!response.ok && response.status !== 404) throw new Error('Failed to delete task');
      queryClient.invalidateQueries({ queryKey: ['/api/tasks'] });
    } catch (error) {
      console.error('Error deleting task:', error);
      // Rollback
      if (previousTasks) {
        queryClient.setQueryData(['/api/tasks'], previousTasks);
      }
    }
  };

  if (isLoadingUser) {
    return (
      <div className="flex items-center justify-center min-h-screen bg-background">
        <Loader2 className="h-8 w-8 animate-spin text-primary" />
      </div>
    );
  }

  // Setup Redirect
  if (setupStatus && !setupStatus.isSetup) {
    return (
      <Switch>
        <Route path="/setup" component={SetupWizard} />
        <Route component={() => <SetupWizard />} />
      </Switch>
    );
  }


  if (isBlocked) {
    return (
      <div className="min-h-screen bg-background w-full">
        <Switch>
          <Route path="/focus/routine/:type" component={FocusRoutinePage} />
          {/* Catch all redirects to nothing, the hook handles the push to routine page */}
          <Route component={() => <div />} />
        </Switch>
        <Toaster />
      </div>
    );
  }

  if (!user) {
    return (
      <div className="min-h-screen bg-background w-full">
        <Switch>
          <Route path="/auth" component={AuthPage} />
          <Route path="/achievements" component={AchievementsPage} />
          <Route path="/leaderboard" component={LeaderboardPage} />
          <Route path="/time-tracking" component={TimeTrackingPage} />
          <Route path="/ai" component={AiChatPage} />
          <Route component={AuthPage} />
        </Switch>
        <Toaster />
      </div>
    );
  }

  return (
    <TooltipProvider>
      <SidebarProvider>
        <AppSidebar user={user} />
        <SidebarInset>
          <div className={`min-h-screen bg-background flex flex-col ${adhdEnabled ? 'adhd-mode' : ''} ${adhdEnabled && adhdSettings.reducedAnimations ? 'reduced-motion' : ''} ${adhdEnabled && adhdSettings.largerTargets ? 'larger-targets' : ''}`}>
            {/* Mobile Header with Sidebar Toggle */}
            <header className="sticky top-0 z-50 flex items-center gap-3 px-4 py-3 bg-background/80 backdrop-blur-xl border-b border-border/50 md:hidden">
              <SidebarTrigger className="h-9 w-9" />
              <div className="flex items-center gap-2">
                <img src="/favicon.png" alt="Logo" className="w-7 h-7 rounded-lg" />
                <span className="font-bold text-lg">{t('app.title')}</span>
              </div>
            </header>
            <main className="flex-1 p-4 md:p-6 max-w-screen-2xl mx-auto w-full relative">
              <Switch>
                <Route path="/">
                  <FocusMode
                    tasks={tasks}
                    onTaskUpdate={handleTaskUpdate}
                    onTaskEdit={handleTaskClick}
                    onTaskDelete={handleTaskDelete}
                    onStartTimer={startTimer}
                    onStopTimer={stopTimer}
                    onNavigateToTasks={() => setLocation('/tasks')}
                  />
                </Route>
                <Route path="/focus">
                  <FocusMode
                    tasks={tasks}
                    onTaskUpdate={handleTaskUpdate}
                    onTaskEdit={handleTaskClick}
                    onTaskDelete={handleTaskDelete}
                    onStartTimer={startTimer}
                    onStopTimer={stopTimer}
                    onNavigateToTasks={() => setLocation('/tasks')}
                  />
                </Route>
                <Route path="/calendar">
                  <CalendarView tasks={tasks} />
                </Route>
                <Route path="/weeklist">
                  <WeekListView tasks={tasks} onTaskUpdate={handleTaskUpdate} />
                </Route>
                <Route path="/kanban">
                  <KanbanBoard
                    tasks={tasks}
                    onTaskUpdate={handleTaskUpdate}
                    onTaskEdit={handleTaskClick}
                    onTaskDelete={handleTaskDelete}
                  />
                </Route>
                <Route path="/auth">
                  {() => {
                    setLocation('/');
                    return null;
                  }}
                </Route>
                <Route path="/tasks">
                  <TasksWithCalendar
                    tasks={tasks}
                    onTaskUpdate={handleTaskUpdate}
                    onTaskEdit={handleTaskClick}
                    onTaskDelete={handleTaskDelete}
                    onStartTimer={startTimer}
                    onStopTimer={stopTimer}
                  />
                </Route>
                <Route path="/templates">
                  <ProjectTemplate
                    onCreateFromTemplate={handleCreateFromTemplate}
                    onCreateTasks={(newTasks) => {
                      queryClient.setQueryData(['/api/tasks'], (old: Task[] = []) => [...old, ...newTasks]);
                      queryClient.invalidateQueries({ queryKey: ['/api/tasks'] });
                    }}
                    onNavigateToSettings={() => setLocation('/settings')}
                  />
                </Route>
                <Route path="/achievements">
                  <AchievementsPage user={user} />
                </Route>

                <Route path="/unscheduled">
                  <UnscheduledTasksPage
                    user={user}
                    onToggleCompletion={(taskId, currentStatus) => handleTaskStatusChange(taskId, currentStatus === 'done' ? 'todo' : 'done')}
                    onDelete={(id) => setDeleteTaskId(id)}
                    onUpdate={handleTaskUpdate}
                    onSelect={setSelectedTask}
                  />
                </Route>
                <Route path="/leaderboard">
                  <LeaderboardPage />
                </Route>
                <Route path="/leaderboard">
                  <LeaderboardPage />
                </Route>
                <Route path="/ai">
                  <AiChatPage />
                </Route>
                <Route path="/notifications">
                  <NotificationsPage />
                </Route>
                <Route path="/time-tracking">
                  <TimeTrackingPage />
                </Route>
                <Route path="/settings">
                  <Settings onNavigateToTemplates={() => setLocation('/templates')} />
                </Route>

                {/* Admin Route */}
                {user?.role === 'admin' && (
                  <>
                    <Route path="/admin/users" component={AdminUserManagement} />
                    <Route path="/admin/settings" component={AdminSettings} />
                  </>
                )}

                <Route path="/focus/routine/:type" component={FocusRoutinePage} />

                {/* ADHD Mode Routes */}
                <Route path="/adhd" component={ADHDDashboardPage} />
                <Route path="/adhd/quick-wins" component={QuickWinsPage} />
                <Route path="/adhd/single-task" component={SingleTaskPage} />
                <Route path="/adhd/body-doubling" component={BodyDoublingPage} />

                <Route component={NotFound} />
              </Switch>
            </main>

            {/* Floating Action Button */}
            <div className="fixed bottom-8 right-8 z-[100]">
              <Button
                size="icon"
                className="h-14 w-14 rounded-full shadow-2xl bg-gradient-to-r from-violet-600 to-indigo-600 hover:scale-110 transition-transform duration-200"
                onClick={() => setIsCreateModalOpen(true)}
                data-testid="fab-create-task"
              >
                <Plus className="h-6 w-6 text-white" />
              </Button>
            </div>
            <CommandPalette
              onNavigate={(path) => setLocation(path.startsWith('/') ? path : `/${path}`)}
              onCreateTask={() => setIsCreateModalOpen(true)}
            />

            <PomodoroOverlay
              isOpen={showPomodoro}
              onClose={() => setShowPomodoro(false)}
              taskId={activePomodoroTaskId}
              taskTitle={tasks.find(t => t.id === activePomodoroTaskId)?.title || 'Quick Focus'}
              onCompleteTask={(id) => handleTaskUpdate(id, { status: 'done', isTracking: false })}
            />

            <Toaster />

            {/* ADHD Mode Overlays */}
            {adhdEnabled && <BreakReminderOverlay />}
            {adhdEnabled && adhdSettings.hyperfocusProtection && <HyperfocusGuard maxMinutes={adhdSettings.hyperfocusMaxMinutes} />}
            {adhdEnabled && adhdSettings.positiveMessagingLevel !== 'off' && <EncouragementToast />}

            <TaskCreationModal
              isOpen={isCreateModalOpen}
              onClose={() => setIsCreateModalOpen(false)}
              onSave={handleCreateTask}
            />

            <TaskDetailsModal
              isOpen={isTaskDetailsOpen}
              onClose={handleTaskDetailsClose}
              task={selectedTask}
              onSave={handleTaskDetailsSave}
              labels={labels}
              onNavigate={(id) => {
                const t = tasks.find(x => x.id === id);
                if (t) setSelectedTask(t);
              }}
            />

            <AlertDialog open={deleteTaskId !== null} onOpenChange={(open) => !open && setDeleteTaskId(null)}>
              <AlertDialogContent data-testid="dialog-delete-confirmation">
                <AlertDialogHeader>
                  <AlertDialogTitle>{t('deleteConfirmation.title')}</AlertDialogTitle>
                  <AlertDialogDescription>
                    {t('deleteConfirmation.description')}
                  </AlertDialogDescription>
                </AlertDialogHeader>
                <AlertDialogFooter>
                  <AlertDialogCancel data-testid="button-cancel-delete">
                    {t('deleteConfirmation.cancel')}
                  </AlertDialogCancel>
                  <AlertDialogAction
                    onClick={confirmTaskDelete}
                    className="bg-destructive text-destructive-foreground hover:bg-destructive/90"
                    data-testid="button-confirm-delete"
                  >
                    {t('deleteConfirmation.confirm')}
                  </AlertDialogAction>
                </AlertDialogFooter>
              </AlertDialogContent>
            </AlertDialog>
          </div>
        </SidebarInset>
      </SidebarProvider>
    </TooltipProvider>
  );


}

// Main App wrapper with ADHD providers
function App() {
  return (
    <ADHDModeProvider>
      <BreakReminderProvider>
        <AppContent />
      </BreakReminderProvider>
    </ADHDModeProvider>
  );
}

export default App;