"use client";

// ============================================================================
// Projects Page (Target Channels) - Enhanced with Statistics
// ============================================================================

import { useEffect, useState } from "react";
import { useParams } from "next/navigation";
import Link from "next/link";
import {
  Loader2,
  Tv,
  ExternalLink,
  Grid,
  List,
  TrendingUp,
  Users,
  Eye,
  ShoppingCart,
  Info,
  Bot,
  Settings,
  Folder,
  Archive,
  Trash2,
} from "lucide-react";
import { DashboardHeader } from "@/components/layout/dashboard-header";
import { useWorkspace } from "@/components/providers/workspace-provider";
import { demoAwareAnalyticsApi, demoAwareProjectsApi } from "@/lib/demo";
import { projectsApi } from "@/lib/api";
import { Avatar, AvatarImage, AvatarFallback } from "@/components/ui/avatar";
import {
  Dialog,
  DialogContent,
  DialogDescription,
  DialogFooter,
  DialogHeader,
  DialogTitle,
} from "@/components/ui/dialog";
import {
  AlertDialog,
  AlertDialogAction,
  AlertDialogCancel,
  AlertDialogContent,
  AlertDialogDescription,
  AlertDialogFooter,
  AlertDialogHeader,
  AlertDialogTitle,
} from "@/components/ui/alert-dialog";
import {
  Select,
  SelectContent,
  SelectItem,
  SelectTrigger,
  SelectValue,
} from "@/components/ui/select";
import { Label } from "@/components/ui/label";
import {
  Card,
  CardContent,
  CardDescription,
  CardHeader,
  CardTitle,
} from "@/components/ui/card";
import { Badge } from "@/components/ui/badge";
import { Button } from "@/components/ui/button";
import { Input } from "@/components/ui/input";
import { Alert, AlertDescription } from "@/components/ui/alert";
import {
  Table,
  TableBody,
  TableCell,
  TableHead,
  TableHeader,
  TableRow,
} from "@/components/ui/table";
import {
  Tooltip,
  TooltipContent,
  TooltipProvider,
  TooltipTrigger,
} from "@/components/ui/tooltip";
import { BOT_USERNAME } from "@/lib/utils/constants";
import type { Project, SpendingAnalytics } from "@/lib/types/api";

// ============================================================================
// Types
// ============================================================================

interface ProjectWithStats extends Project {
  stats?: {
    total_cost: number;
    total_subscriptions: number;
    total_views: number;
    avg_cpf: number | null;
  };
}

// ============================================================================
// Helpers
// ============================================================================

const formatNumber = (value: number | null | undefined): string => {
  if (value === null || value === undefined) return "—";
  return new Intl.NumberFormat("ru-RU").format(value);
};

const formatCurrency = (value: number | null | undefined): string => {
  if (value === null || value === undefined) return "—";
  return new Intl.NumberFormat("ru-RU", {
    style: "currency",
    currency: "RUB",
    minimumFractionDigits: 0,
    maximumFractionDigits: 0,
  }).format(value);
};

// ============================================================================
// Component
// ============================================================================

export default function ProjectsPage() {
  const params = useParams();
  const workspaceId = params?.workspaceId as string;
  const { projects, isLoadingProjects, currentWorkspace, refreshProjects } = useWorkspace();

  const [projectsWithStats, setProjectsWithStats] = useState<ProjectWithStats[]>([]);
  const [loadingStats, setLoadingStats] = useState(false);
  const [viewMode, setViewMode] = useState<"grid" | "table">("grid");
  const [settingsProject, setSettingsProject] = useState<Project | null>(null);
  const [inviteLinkType, setInviteLinkType] = useState<"public" | "approval">("public");
  const [isUpdatingSettings, setIsUpdatingSettings] = useState(false);
  const [isArchiving, setIsArchiving] = useState(false);
  const [isDeleting, setIsDeleting] = useState(false);
  const [showDeleteDialog, setShowDeleteDialog] = useState(false);
  const [deleteConfirmationText, setDeleteConfirmationText] = useState("");
  const { isDemoMode } = useWorkspace();

  const handleOpenSettings = (project: Project) => {
    setSettingsProject(project);
    setInviteLinkType(project.purchase_invite_type_default || "public");
  };

  const handleSaveSettings = async () => {
    if (!settingsProject) return;

    try {
      setIsUpdatingSettings(true);
      const api = isDemoMode ? demoAwareProjectsApi : projectsApi;
      await api.updateInviteLinkType(workspaceId, settingsProject.id, {
        purchase_invite_type_default: inviteLinkType,
      });
      await refreshProjects();
      setSettingsProject(null);
    } catch (err) {
      console.error("Failed to update settings:", err);
    } finally {
      setIsUpdatingSettings(false);
    }
  };

  const handleArchive = async () => {
    if (!settingsProject) return;

    try {
      setIsArchiving(true);
      const api = isDemoMode ? demoAwareProjectsApi : projectsApi;
      await api.archive(workspaceId, settingsProject.id);
      await refreshProjects();
      setSettingsProject(null);
    } catch (err) {
      console.error("Failed to archive project:", err);
    } finally {
      setIsArchiving(false);
    }
  };

  const handleDelete = async () => {
    if (!settingsProject) return;

    try {
      setIsDeleting(true);
      const api = isDemoMode ? demoAwareProjectsApi : projectsApi;
      await api.delete(workspaceId, settingsProject.id);
      await refreshProjects();
      setSettingsProject(null);
      setShowDeleteDialog(false);
      setDeleteConfirmationText("");
    } catch (err) {
      console.error("Failed to delete project:", err);
    } finally {
      setIsDeleting(false);
    }
  };

  const handleOpenDeleteDialog = () => {
    setShowDeleteDialog(true);
  };

  const handleCloseDeleteDialog = () => {
    setShowDeleteDialog(false);
    setDeleteConfirmationText("");
  };

  const getChannelAvatar = (project: Project) => {
    // Telegram channel avatar URL format
    if (project.username) {
      return `https://t.me/i/userpic/320/${project.username}.jpg`;
    }
    return null;
  };

  // Load statistics for each project
  useEffect(() => {
    if (projects.length === 0) {
      setProjectsWithStats([]);
      return;
    }

    const loadStats = async () => {
      setLoadingStats(true);
      try {
        const statsPromises = projects.map(async (project) => {
          try {
            const spending = await demoAwareAnalyticsApi.spending(workspaceId, {
              project_id: project.id,
            });
            return {
              ...project,
              stats: {
                total_cost: spending.total_cost,
                total_subscriptions: spending.total_subscriptions,
                total_views: spending.total_views,
                avg_cpf:
                  spending.total_subscriptions > 0
                    ? spending.total_cost / spending.total_subscriptions
                    : null,
              },
            };
          } catch {
            return { ...project, stats: undefined };
          }
        });

        const results = await Promise.all(statsPromises);
        setProjectsWithStats(results);
      } catch (err) {
        console.error("Failed to load project stats:", err);
        setProjectsWithStats(projects);
      } finally {
        setLoadingStats(false);
      }
    };

    loadStats();
  }, [projects, workspaceId]);

  const isLoading = isLoadingProjects || loadingStats;

  return (
    <TooltipProvider>
      <DashboardHeader
        breadcrumbs={[
          { label: "Главная", href: `/dashboard/${currentWorkspace?.id}` },
          { label: "Проекты" },
        ]}
      />

      <div className="flex flex-1 flex-col gap-4 p-4 pt-0 mt-4">
        <div className="flex items-center justify-between">
          <div>
            <h1 className="text-2xl font-bold tracking-tight">Проекты</h1>
            <p className="text-muted-foreground">
              Telegram каналы, которые вы продвигаете
            </p>
          </div>
          <div className="flex items-center gap-2 border rounded-lg p-1">
            <Button
              variant={viewMode === "grid" ? "secondary" : "ghost"}
              size="sm"
              onClick={() => setViewMode("grid")}
              aria-label="Плиточный вид"
            >
              <Grid className="h-4 w-4" />
            </Button>
            <Button
              variant={viewMode === "table" ? "secondary" : "ghost"}
              size="sm"
              onClick={() => setViewMode("table")}
              aria-label="Табличный вид"
            >
              <List className="h-4 w-4" />
            </Button>
          </div>
        </div>

        <Alert>
          <Tv className="h-4 w-4" />
          <AlertDescription className="flex items-center justify-between flex-wrap gap-3">
            <span>
              Чтобы добавить новый проект, добавьте бота{" "}
              <a
                href={`https://t.me/${BOT_USERNAME}`}
                target="_blank"
                rel="noopener noreferrer"
                className="font-mono text-primary hover:underline inline-flex items-center gap-1"
              >
                @{BOT_USERNAME}
                <ExternalLink className="h-3 w-3" />
              </a>{" "}
              администратором в ваш Telegram канал.
            </span>
            <Button
              asChild
              size="sm"
              className="shrink-0"
            >
              <a
                href={`tg://resolve?domain=${BOT_USERNAME}&startchannel&admin=invite_users+post_messages+edit_messages+delete_messages`}
                target="_blank"
                rel="noopener noreferrer"
              >
                <Bot className="h-4 w-4 mr-2" />
                Добавить бота
              </a>
            </Button>
          </AlertDescription>
        </Alert>

        {isLoading ? (
          <div className="flex items-center justify-center py-12">
            <Loader2 className="h-8 w-8 animate-spin text-muted-foreground" />
          </div>
        ) : projectsWithStats.length === 0 ? (
          <Card>
            <CardContent className="flex flex-col items-center justify-center py-12">
              <Tv className="h-12 w-12 text-muted-foreground mb-4" />
              <h3 className="text-lg font-semibold mb-2">Нет проектов</h3>
              <p className="text-muted-foreground text-center max-w-md">
                Добавьте бота администратором в ваш Telegram канал, и он
                автоматически появится здесь как проект.
              </p>
            </CardContent>
          </Card>
        ) : viewMode === "table" ? (
          // Table View
          <Card>
            <Table>
              <TableHeader>
                <TableRow>
                  <TableHead>Канал</TableHead>
                  <TableHead>Статус</TableHead>
                  <TableHead className="text-right">
                    <div className="flex items-center justify-end gap-1">
                      Подписчиков
                      <Tooltip>
                        <TooltipTrigger asChild>
                          <Info className="h-3.5 w-3.5 text-muted-foreground cursor-help" />
                        </TooltipTrigger>
                        <TooltipContent>
                          Количество подписчиков в канале
                        </TooltipContent>
                      </Tooltip>
                    </div>
                  </TableHead>
                  <TableHead className="text-right">
                    <div className="flex items-center justify-end gap-1">
                      Привлечено подписчиков
                      <Tooltip>
                        <TooltipTrigger asChild>
                          <Info className="h-3.5 w-3.5 text-muted-foreground cursor-help" />
                        </TooltipTrigger>
                        <TooltipContent>
                          Привлеченные подписчики по пригласительным ссылкам
                        </TooltipContent>
                      </Tooltip>
                    </div>
                  </TableHead>
                  <TableHead className="text-right">
                    <div className="flex items-center justify-end gap-1">
                      Суммарный охват
                      <Tooltip>
                        <TooltipTrigger asChild>
                          <Info className="h-3.5 w-3.5 text-muted-foreground cursor-help" />
                        </TooltipTrigger>
                        <TooltipContent>
                          Суммарные просмотры рекламных постов
                        </TooltipContent>
                      </Tooltip>
                    </div>
                  </TableHead>
                  <TableHead className="text-right">
                    <div className="flex items-center justify-end gap-1">
                      CPF
                      <Tooltip>
                        <TooltipTrigger asChild>
                          <Info className="h-3.5 w-3.5 text-muted-foreground cursor-help" />
                        </TooltipTrigger>
                        <TooltipContent>
                          Cost Per Follower — средняя стоимость подписчика
                        </TooltipContent>
                      </Tooltip>
                    </div>
                  </TableHead>
                  <TableHead className="w-[200px]"></TableHead>
                </TableRow>
              </TableHeader>
              <TableBody>
                {projectsWithStats.map((project) => (
                  <TableRow key={project.id}>
                    <TableCell>
                      <div className="flex items-center gap-3">
                        <Avatar className="h-9 w-9">
                          <AvatarImage src={getChannelAvatar(project) || undefined} alt={project.title} />
                          <AvatarFallback className="rounded-lg bg-primary/10">
                            <Tv className="h-4 w-4 text-primary" />
                          </AvatarFallback>
                        </Avatar>
                        <div>
                          <div className="font-medium">{project.title}</div>
                          {project.username && (
                            <a
                              href={`https://t.me/${project.username}`}
                              target="_blank"
                              rel="noopener noreferrer"
                              className="text-xs text-muted-foreground hover:underline inline-flex items-center gap-0.5"
                            >
                              @{project.username}
                              <ExternalLink className="h-2.5 w-2.5" />
                            </a>
                          )}
                        </div>
                      </div>
                    </TableCell>
                    <TableCell>
                      <Badge
                        variant={project.status === "active" ? "default" : "secondary"}
                      >
                        {project.status === "active"
                          ? "Активен"
                          : project.status === "inactive"
                          ? "Неактивен"
                          : "Архив"}
                      </Badge>
                    </TableCell>
                    <TableCell className="text-right">
                      {formatNumber(project.subscribers_count)}
                    </TableCell>
                    <TableCell className="text-right">
                      {formatNumber(project.stats?.total_subscriptions)}
                    </TableCell>
                    <TableCell className="text-right">
                      {formatNumber(project.stats?.total_views)}
                    </TableCell>
                    <TableCell className="text-right">
                      {formatCurrency(project.stats?.avg_cpf)}
                    </TableCell>
                    <TableCell>
                      <div className="flex gap-1 flex-wrap">
                        <Button variant="outline" size="sm" asChild>
                          <Link
                            href={`/dashboard/${currentWorkspace?.id}/purchase-plans/${project.id}`}
                          >
                            План закупов
                          </Link>
                        </Button>
                        <Button variant="outline" size="sm" asChild>
                          <Link
                            href={`/dashboard/${currentWorkspace?.id}/creatives?project_id=${project.id}`}
                          >
                            <Folder className="h-3 w-3 mr-1" />
                            Креативы
                          </Link>
                        </Button>
                        <Button
                          variant="outline"
                          size="sm"
                          onClick={() => handleOpenSettings(project)}
                        >
                          <Settings className="h-3 w-3 mr-1" />
                          Настройки
                        </Button>
                      </div>
                    </TableCell>
                  </TableRow>
                ))}
              </TableBody>
            </Table>
          </Card>
        ) : (
          // Grid View
          <div className="grid gap-4 md:grid-cols-2 lg:grid-cols-3">
            {projectsWithStats.map((project) => (
              <Card key={project.id}>
                <CardHeader>
                  <div className="flex items-start justify-between">
                    <div className="flex items-center gap-3">
                      <Avatar className="h-10 w-10">
                        <AvatarImage src={getChannelAvatar(project) || undefined} alt={project.title} />
                        <AvatarFallback className="rounded-lg bg-primary/10">
                          <Tv className="h-5 w-5 text-primary" />
                        </AvatarFallback>
                      </Avatar>
                      <div>
                        <CardTitle className="text-base">{project.title}</CardTitle>
                        {project.username && (
                          <CardDescription>
                            <a
                              href={`https://t.me/${project.username}`}
                              target="_blank"
                              rel="noopener noreferrer"
                              className="hover:underline inline-flex items-center gap-0.5"
                            >
                              @{project.username}
                              <ExternalLink className="h-2.5 w-2.5" />
                            </a>
                          </CardDescription>
                        )}
                      </div>
                    </div>
                    <Badge
                      variant={project.status === "active" ? "default" : "secondary"}
                    >
                      {project.status === "active"
                        ? "Активен"
                        : project.status === "inactive"
                        ? "Неактивен"
                        : "Архив"}
                    </Badge>
                  </div>
                </CardHeader>
                <CardContent className="space-y-4">
                  {/* Stats Grid */}
                  <div className="grid grid-cols-2 gap-3 text-sm">
                    {project.subscribers_count !== undefined && (
                      <div className="flex items-center gap-2">
                        <Users className="h-4 w-4 text-muted-foreground" />
                        <div>
                          <div className="font-medium">
                            {formatNumber(project.subscribers_count)}
                          </div>
                          <div className="text-xs text-muted-foreground">
                            Подписчиков
                          </div>
                        </div>
                      </div>
                    )}
                    {project.stats && (
                      <>
                        <div className="flex items-center gap-2">
                          <Users className="h-4 w-4 text-muted-foreground" />
                          <div>
                            <div className="font-medium">
                              {formatNumber(project.stats.total_subscriptions)}
                            </div>
                            <div className="text-xs text-muted-foreground">
                              Привлечено подписчиков
                            </div>
                          </div>
                        </div>
                        <div className="flex items-center gap-2">
                          <Eye className="h-4 w-4 text-muted-foreground" />
                          <div>
                            <div className="font-medium">
                              {formatNumber(project.stats.total_views)}
                            </div>
                            <div className="text-xs text-muted-foreground">
                              Суммарный охват
                            </div>
                          </div>
                        </div>
                        <div className="flex items-center gap-2">
                          <TrendingUp className="h-4 w-4 text-muted-foreground" />
                          <div>
                            <div className="font-medium">
                              {formatCurrency(project.stats.avg_cpf)}
                            </div>
                            <div className="text-xs text-muted-foreground">
                              CPF
                            </div>
                          </div>
                        </div>
                      </>
                    )}
                  </div>

                  {/* Actions */}
                  <div className="flex gap-2 flex-wrap">
                    <Button variant="outline" size="sm" asChild>
                      <Link
                        href={`/dashboard/${currentWorkspace?.id}/purchase-plans/${project.id}`}
                      >
                        План закупов
                      </Link>
                    </Button>
                    <Button variant="outline" size="sm" asChild>
                      <Link
                        href={`/dashboard/${currentWorkspace?.id}/creatives?project_id=${project.id}`}
                      >
                        <Folder className="h-4 w-4 mr-1" />
                        Креативы
                      </Link>
                    </Button>
                    <Button
                      variant="outline"
                      size="sm"
                      onClick={() => handleOpenSettings(project)}
                    >
                      <Settings className="h-4 w-4 mr-1" />
                      Настройки
                    </Button>
                  </div>
                </CardContent>
              </Card>
            ))}
          </div>
        )}

        {/* Settings Dialog */}
        <Dialog open={!!settingsProject} onOpenChange={(open) => !open && setSettingsProject(null)}>
          <DialogContent className="sm:max-w-md">
            <DialogHeader>
              <DialogTitle>Настройки проекта</DialogTitle>
              <DialogDescription>
                {settingsProject?.title}
              </DialogDescription>
            </DialogHeader>
            <div className="space-y-4 py-4">
              <div className="space-y-2">
                <Label htmlFor="invite-link-type">Тип ссылки по умолчанию</Label>
                <Select
                  value={inviteLinkType}
                  onValueChange={(value) => setInviteLinkType(value as "public" | "approval")}
                >
                  <SelectTrigger id="invite-link-type">
                    <SelectValue />
                  </SelectTrigger>
                  <SelectContent>
                    <SelectItem value="public">Открытая</SelectItem>
                    <SelectItem value="approval">С заявками</SelectItem>
                  </SelectContent>
                </Select>
                <p className="text-xs text-muted-foreground">
                  Тип пригласительной ссылки, который будет использоваться по умолчанию при создании размещений для этого проекта
                </p>
              </div>

              {/* Danger Zone */}
              <div className="space-y-3 pt-4 border-t">
                <div className="space-y-2">
                  <h4 className="text-sm font-semibold text-destructive">Опасная зона</h4>
                  <div className="flex flex-col gap-2">
                    {settingsProject?.status !== "archived" && (
                      <Button
                        variant="outline"
                        onClick={handleArchive}
                        disabled={isArchiving || isDeleting || isUpdatingSettings}
                        className="w-full justify-start"
                      >
                        {isArchiving ? (
                          <>
                            <Loader2 className="h-4 w-4 animate-spin mr-2" />
                            Архивирование...
                          </>
                        ) : (
                          <>
                            <Archive className="h-4 w-4 mr-2" />
                            Архивировать проект
                          </>
                        )}
                      </Button>
                    )}
                    <Button
                      variant="destructive"
                      onClick={handleOpenDeleteDialog}
                      disabled={isArchiving || isDeleting || isUpdatingSettings}
                      className="w-full justify-start"
                    >
                      <Trash2 className="h-4 w-4 mr-2" />
                      Удалить проект
                    </Button>
                  </div>
                </div>
              </div>
            </div>
            <DialogFooter>
              <Button
                variant="outline"
                onClick={() => setSettingsProject(null)}
              >
                Отмена
              </Button>
              <Button
                onClick={handleSaveSettings}
                disabled={isUpdatingSettings || isArchiving || isDeleting}
              >
                {isUpdatingSettings ? (
                  <>
                    <Loader2 className="h-4 w-4 animate-spin mr-2" />
                    Сохранение...
                  </>
                ) : (
                  "Сохранить"
                )}
              </Button>
            </DialogFooter>
          </DialogContent>
        </Dialog>

        {/* Delete Confirmation Dialog */}
        <AlertDialog open={showDeleteDialog} onOpenChange={handleCloseDeleteDialog}>
          <AlertDialogContent>
            <AlertDialogHeader>
              <AlertDialogTitle>Удалить проект "{settingsProject?.title}"?</AlertDialogTitle>
              <AlertDialogDescription>
                Это действие необратимо. Все данные проекта будут удалены, включая креативы, размещения и аналитику.
                <br /><br />
                Для подтверждения введите <strong>Удалить {settingsProject?.title}</strong> ниже:
              </AlertDialogDescription>
            </AlertDialogHeader>
            <div className="space-y-4 py-4">
              <Input
                placeholder={`Удалить ${settingsProject?.title}`}
                value={deleteConfirmationText}
                onChange={(e) => setDeleteConfirmationText(e.target.value)}
                className="mt-4"
              />
            </div>
            <AlertDialogFooter>
              <AlertDialogCancel onClick={handleCloseDeleteDialog}>
                Отмена
              </AlertDialogCancel>
              <AlertDialogAction
                onClick={handleDelete}
                disabled={isDeleting || deleteConfirmationText !== `Удалить ${settingsProject?.title}`}
                className="bg-destructive text-destructive-foreground hover:bg-destructive/90"
              >
                {isDeleting ? (
                  <>
                    <Loader2 className="h-4 w-4 animate-spin mr-2" />
                    Удаление...
                  </>
                ) : (
                  "Удалить"
                )}
              </AlertDialogAction>
            </AlertDialogFooter>
          </AlertDialogContent>
        </AlertDialog>
      </div>
    </TooltipProvider>
  );
}