"use client";

import { useState, useTransition, useCallback } from "react";
import { useRouter } from "next/navigation";
import Image from "next/image";
import Link from "next/link";
import {
  Select,
  SelectContent,
  SelectItem,
  SelectTrigger,
  SelectValue,
} from "@/components/ui/select";
import { Badge } from "@/components/ui/badge";
import { Textarea } from "@/components/ui/textarea";
import { cn } from "@/lib/utils";
import { updateShotNotes } from "@/actions/shots";
import { useToast } from "@/components/ui/use-toast";
import {
  Film,
  Clock,
  CheckCircle2,
  AlertCircle,
  Calendar,
  ChevronDown,
  ChevronRight,
  Loader2,
} from "lucide-react";
import { format } from "date-fns";

type ShotRow = {
  id: string;
  shotCode: string;
  scene: string;
  episode: string | null;
  shotNumber: number;
  status: string;
  priority: string;
  dueDate: Date | string | null;
  thumbnailUrl: string | null;
  notes: string | null;
  description: string | null;
  artist: { id: string; name: string | null; image: string | null; email: string } | null;
};

interface Project {
  id: string;
  name: string;
  code: string;
  projectType: string;
}

interface ShotStatusClientProps {
  projects: Project[];
  selectedProjectId: string | null;
  selectedProject: Project | null;
  shots: ShotRow[];
  canManage: boolean;
}

const STATUS_CONFIG: Record<string, { label: string; color: string; icon: React.ElementType }> = {
  WAITING: { label: "Waiting", color: "bg-zinc-500/10 text-zinc-400 border-zinc-500/20", icon: Clock },
  IN_PROGRESS: { label: "In Progress", color: "bg-blue-500/10 text-blue-400 border-blue-500/20", icon: Film },
  IN_REVIEW: { label: "In Review", color: "bg-purple-500/10 text-purple-400 border-purple-500/20", icon: AlertCircle },
  REVISIONS: { label: "Revisions", color: "bg-orange-500/10 text-orange-400 border-orange-500/20", icon: AlertCircle },
  COMPLETE: { label: "Complete", color: "bg-emerald-500/10 text-emerald-400 border-emerald-500/20", icon: CheckCircle2 },
};

function NotesCell({
  shot,
  canManage,
}: {
  shot: ShotRow;
  canManage: boolean;
}) {
  const [value, setValue] = useState(shot.notes ?? "");
  const [saved, setSaved] = useState(true);
  const [isPending, startTransition] = useTransition();
  const { toast } = useToast();

  const handleBlur = useCallback(() => {
    if (value === (shot.notes ?? "")) return;
    startTransition(async () => {
      try {
        await updateShotNotes(shot.id, value);
        setSaved(true);
        toast({ title: "Notes saved" });
      } catch {
        toast({ title: "Failed to save notes", variant: "destructive" });
      }
    });
  }, [value, shot.id, shot.notes, toast]);

  if (!canManage) {
    return (
      <span className="text-sm text-zinc-400 whitespace-pre-wrap">
        {shot.notes ?? <span className="italic text-zinc-600">—</span>}
      </span>
    );
  }

  return (
    <div className="relative">
      <Textarea
        value={value}
        onChange={(e) => { setValue(e.target.value); setSaved(false); }}
        onBlur={handleBlur}
        placeholder="Add notes..."
        className="min-h-[60px] text-sm resize-none bg-zinc-900 border-zinc-700 focus:border-zinc-500 text-zinc-200 placeholder:text-zinc-600"
        rows={2}
      />
      {isPending && (
        <Loader2 className="absolute bottom-2 right-2 h-3 w-3 animate-spin text-zinc-500" />
      )}
      {!isPending && !saved && (
        <span className="absolute bottom-1.5 right-2 text-[10px] text-zinc-500">unsaved</span>
      )}
    </div>
  );
}

function ShotTable({ shots, canManage, projectId }: { shots: ShotRow[]; canManage: boolean; projectId: string }) {
  return (
    <table className="w-full text-sm">
      <thead>
        <tr className="border-b border-zinc-800">
          <th className="text-left py-2 px-3 text-xs font-medium text-zinc-500 w-32">Thumb</th>
          <th className="text-left py-2 px-3 text-xs font-medium text-zinc-500">Shot</th>
          <th className="text-left py-2 px-3 text-xs font-medium text-zinc-500 w-32">Status</th>
          <th className="text-left py-2 px-3 text-xs font-medium text-zinc-500 w-32">Due Date</th>
          <th className="text-left py-2 px-3 text-xs font-medium text-zinc-500">Notes</th>
        </tr>
      </thead>
      <tbody className="divide-y divide-zinc-800/60">
        {shots.map((shot) => {
          const cfg = STATUS_CONFIG[shot.status] ?? STATUS_CONFIG.WAITING;
          const StatusIcon = cfg.icon;
          const dueDate = shot.dueDate ? new Date(shot.dueDate) : null;
          const isOverdue = dueDate && dueDate < new Date() && shot.status !== "COMPLETE";

          return (
            <tr key={shot.id} className="hover:bg-zinc-800/30 transition-colors">
              {/* Thumbnail */}
              <td className="py-2 px-3">
                <div className="w-24 aspect-[2.39/1] rounded overflow-hidden bg-zinc-800 flex items-center justify-center shrink-0">
                  {shot.thumbnailUrl ? (
                    <Image
                      src={shot.thumbnailUrl}
                      alt={shot.shotCode}
                      width={96}
                      height={40}
                      className="object-cover w-full h-full"
                    />
                  ) : (
                    <Film className="h-4 w-4 text-zinc-600" />
                  )}
                </div>
              </td>

              {/* Shot name */}
              <td className="py-2 px-3">
                <Link
                  href={`/projects/${projectId}/shots/${shot.id}`}
                  className="font-mono text-sm text-white hover:text-blue-400 transition-colors"
                >
                  {shot.shotCode}
                </Link>
                {shot.description && (
                  <p className="text-xs text-zinc-500 mt-0.5 truncate max-w-[200px]">
                    {shot.description}
                  </p>
                )}
              </td>

              {/* Status */}
              <td className="py-2 px-3">
                <Badge className={cn("gap-1 text-xs", cfg.color)}>
                  <StatusIcon className="h-3 w-3" />
                  {cfg.label}
                </Badge>
              </td>

              {/* Due date */}
              <td className="py-2 px-3">
                {dueDate ? (
                  <span
                    className={cn(
                      "flex items-center gap-1 text-xs",
                      isOverdue ? "text-red-400" : "text-zinc-400"
                    )}
                  >
                    <Calendar className="h-3 w-3" />
                    {format(dueDate, "d MMM yyyy")}
                  </span>
                ) : (
                  <span className="text-xs text-zinc-600 italic">—</span>
                )}
              </td>

              {/* Notes */}
              <td className="py-2 px-3 min-w-[220px]">
                <NotesCell shot={shot} canManage={canManage} />
              </td>
            </tr>
          );
        })}
      </tbody>
    </table>
  );
}

export function ShotStatusClient({
  projects,
  selectedProjectId,
  selectedProject,
  shots,
  canManage,
}: ShotStatusClientProps) {
  const router = useRouter();
  const [collapsedEpisodes, setCollapsedEpisodes] = useState<Set<string>>(new Set());

  const toggleEpisode = (ep: string) =>
    setCollapsedEpisodes((prev) => {
      const next = new Set(prev);
      next.has(ep) ? next.delete(ep) : next.add(ep);
      return next;
    });

  const handleProjectChange = (id: string) => {
    router.push(`/shot-status?projectId=${id}`);
  };

  // Group by episode for episodic projects
  const isEpisodic = selectedProject?.projectType === "EPISODIC";
  const episodeGroups: [string, ShotRow[]][] = isEpisodic
    ? (() => {
        const map = new Map<string, ShotRow[]>();
        for (const shot of shots) {
          const key = shot.episode ?? "(No Episode)";
          if (!map.has(key)) map.set(key, []);
          map.get(key)!.push(shot);
        }
        return Array.from(map.entries());
      })()
    : [];

  const statusCounts = shots.reduce(
    (acc, s) => {
      acc[s.status] = (acc[s.status] ?? 0) + 1;
      return acc;
    },
    {} as Record<string, number>
  );

  return (
    <div className="p-8 space-y-6 max-w-[1600px] mx-auto">
      {/* Header */}
      <div>
        <h1 className="text-3xl font-bold text-white">Shot Status</h1>
        <p className="text-zinc-400 mt-1">Track shot progress and add production notes</p>
      </div>

      {/* Project selector */}
      <div className="flex items-center gap-3">
        <label className="text-sm text-zinc-400 shrink-0">Project:</label>
        <Select value={selectedProjectId ?? ""} onValueChange={handleProjectChange}>
          <SelectTrigger className="w-72">
            <SelectValue placeholder="Select a project..." />
          </SelectTrigger>
          <SelectContent>
            {projects.map((p) => (
              <SelectItem key={p.id} value={p.id}>
                <span className="font-mono text-xs text-zinc-400 mr-2">{p.code}</span>
                {p.name}
              </SelectItem>
            ))}
          </SelectContent>
        </Select>
      </div>

      {/* No project selected */}
      {!selectedProject && (
        <div className="text-center py-20 text-zinc-500">
          <Film className="h-10 w-10 mx-auto mb-3 opacity-30" />
          <p>Select a project to view shot status</p>
        </div>
      )}

      {/* Shots table */}
      {selectedProject && shots.length === 0 && (
        <div className="text-center py-20 text-zinc-500">
          <Film className="h-10 w-10 mx-auto mb-3 opacity-30" />
          <p>No shots in this project yet</p>
        </div>
      )}

      {selectedProject && shots.length > 0 && (
        <>
          {/* Summary pills */}
          <div className="flex flex-wrap gap-2">
            <span className="text-xs text-zinc-500 self-center">{shots.length} shots total</span>
            {Object.entries(STATUS_CONFIG).map(([key, cfg]) => {
              const count = statusCounts[key] ?? 0;
              if (!count) return null;
              return (
                <Badge key={key} className={cn("gap-1 text-xs", cfg.color)}>
                  {count} {cfg.label}
                </Badge>
              );
            })}
          </div>

          {/* Table */}
          <div className="rounded-xl border border-zinc-800 bg-zinc-900/50 overflow-hidden">
            {isEpisodic ? (
              <div className="divide-y divide-zinc-800">
                {episodeGroups.map(([episode, episodeShots]) => {
                  const collapsed = collapsedEpisodes.has(episode);
                  return (
                    <div key={episode}>
                      <button
                        onClick={() => toggleEpisode(episode)}
                        className="flex items-center gap-2 w-full px-4 py-3 bg-zinc-800/60 hover:bg-zinc-800/90 transition-colors text-left"
                      >
                        {collapsed ? (
                          <ChevronRight className="h-4 w-4 text-zinc-400 shrink-0" />
                        ) : (
                          <ChevronDown className="h-4 w-4 text-zinc-400 shrink-0" />
                        )}
                        <span className="font-semibold text-sm text-white">Episode {episode}</span>
                        <span className="text-xs text-zinc-500 font-normal">
                          {episodeShots.length} shot{episodeShots.length !== 1 ? "s" : ""}
                        </span>
                      </button>
                      {!collapsed && (
                        <div className="overflow-x-auto">
                          <ShotTable shots={episodeShots} canManage={canManage} projectId={selectedProjectId!} />
                        </div>
                      )}
                    </div>
                  );
                })}
              </div>
            ) : (
              <div className="overflow-x-auto">
                <ShotTable shots={shots} canManage={canManage} projectId={selectedProjectId!} />
              </div>
            )}
          </div>
        </>
      )}
    </div>
  );
}