"use client";

import { useRef, useState, useCallback } from "react";
import { Upload, X, Loader2, ImageIcon, ZoomIn, Pencil } from "lucide-react";
import { cn } from "@/lib/utils";
import type { TakeAttachmentData } from "./TakeEditorPanel";
import { SketchPad } from "./SketchPad";

// ─── Lightbox ─────────────────────────────────────────────────────────────────

function Lightbox({
  attachments,
  index,
  onClose,
}: {
  attachments: TakeAttachmentData[];
  index: number;
  onClose: () => void;
}) {
  const [current, setCurrent] = useState(index);
  const att = attachments[current];

  return (
    <div
      className="fixed inset-0 z-50 bg-black/90 flex flex-col items-center justify-center"
      onClick={onClose}
    >
      <button
        className="absolute top-4 right-4 text-white/70 hover:text-white p-2"
        onClick={onClose}
      >
        <X className="h-6 w-6" />
      </button>

      {/* Image */}
      <div
        className="max-w-[90vw] max-h-[80vh] overflow-hidden"
        onClick={(e) => e.stopPropagation()}
      >
        {/* eslint-disable-next-line @next/next/no-img-element */}
        <img
          src={att.fileUrl}
          alt={att.fileName}
          className="max-w-full max-h-[80vh] object-contain rounded-lg"
        />
      </div>

      {/* Caption */}
      {att.caption && (
        <p className="mt-3 text-sm text-zinc-300 max-w-lg text-center">{att.caption}</p>
      )}
      <p className="mt-1 text-xs text-zinc-500">{att.fileName}</p>

      {/* Prev / Next */}
      {attachments.length > 1 && (
        <div className="flex gap-4 mt-4" onClick={(e) => e.stopPropagation()}>
          <button
            disabled={current === 0}
            onClick={() => setCurrent((c) => c - 1)}
            className="px-4 py-2 rounded bg-zinc-800 text-zinc-300 disabled:opacity-30 hover:bg-zinc-700 text-sm"
          >
            ← Prev
          </button>
          <span className="text-zinc-500 text-sm self-center">
            {current + 1} / {attachments.length}
          </span>
          <button
            disabled={current === attachments.length - 1}
            onClick={() => setCurrent((c) => c + 1)}
            className="px-4 py-2 rounded bg-zinc-800 text-zinc-300 disabled:opacity-30 hover:bg-zinc-700 text-sm"
          >
            Next →
          </button>
        </div>
      )}
    </div>
  );
}

// ─── Main component ───────────────────────────────────────────────────────────

interface Props {
  takeId: string;
  attachments: TakeAttachmentData[];
  onChange: (updated: TakeAttachmentData[]) => void;
}

export function TakeImageGallery({ takeId, attachments, onChange }: Props) {
  const fileInputRef = useRef<HTMLInputElement>(null);
  const [uploading, setUploading] = useState(false);
  const [lightboxIndex, setLightboxIndex] = useState<number | null>(null);
  const [dragOver, setDragOver] = useState(false);
  const [showSketch, setShowSketch] = useState(false);

  const imageAttachments = attachments.filter((a) => a.fileType === "IMAGE");

  const uploadFile = useCallback(
    async (file: File) => {
      const formData = new FormData();
      formData.append("file", file);
      formData.append("type", "image");

      const res = await fetch("/api/upload", { method: "POST", body: formData });
      if (!res.ok) throw new Error("Upload failed");
      const { url, key } = await res.json();

      // Register attachment in DB
      const attachRes = await fetch(`/api/shoot-log/takes/${takeId}/attachments`, {
        method: "POST",
        headers: { "Content-Type": "application/json" },
        body: JSON.stringify({
          fileUrl: url,
          fileKey: key ?? "",
          fileName: file.name,
          fileSize: file.size,
          fileType: "IMAGE",
          category: "MISCELLANEOUS",
        }),
      });
      if (!attachRes.ok) throw new Error("Failed to save attachment");
      const { attachment } = await attachRes.json();
      return attachment as TakeAttachmentData;
    },
    [takeId]
  );

  const handleFiles = useCallback(
    async (files: FileList | File[]) => {
      const imageFiles = Array.from(files).filter((f) => f.type.startsWith("image/"));
      if (!imageFiles.length) return;
      setUploading(true);
      try {
        const results = await Promise.all(imageFiles.map(uploadFile));
        onChange([...attachments, ...results]);
      } finally {
        setUploading(false);
      }
    },
    [attachments, onChange, uploadFile]
  );

  const handleDelete = useCallback(
    async (id: string) => {
      const res = await fetch(
        `/api/shoot-log/takes/${takeId}/attachments/${id}`,
        { method: "DELETE" }
      );
      if (res.ok) {
        onChange(attachments.filter((a) => a.id !== id));
      }
    },
    [attachments, onChange, takeId]
  );

  const onDrop = useCallback(
    (e: React.DragEvent) => {
      e.preventDefault();
      setDragOver(false);
      handleFiles(e.dataTransfer.files);
    },
    [handleFiles]
  );

  return (
    <div className="space-y-3">
      {/* Upload zone */}
      <div
        onDragOver={(e) => { e.preventDefault(); setDragOver(true); }}
        onDragLeave={() => setDragOver(false)}
        onDrop={onDrop}
        className={cn(
          "border-2 border-dashed rounded-lg p-4 text-center transition-colors cursor-pointer",
          dragOver
            ? "border-amber-500 bg-amber-500/5"
            : "border-zinc-700 hover:border-zinc-600"
        )}
        onClick={() => fileInputRef.current?.click()}
      >
        <input
          ref={fileInputRef}
          type="file"
          accept="image/*"
          multiple
          capture="environment"
          className="hidden"
          onChange={(e) => e.target.files && handleFiles(e.target.files)}
        />
        {uploading ? (
          <div className="flex items-center justify-center gap-2 text-zinc-400">
            <Loader2 className="h-4 w-4 animate-spin" />
            <span className="text-sm">Uploading...</span>
          </div>
        ) : (
          <div className="flex items-center justify-center gap-2 text-zinc-500">
            <Upload className="h-4 w-4" />
            <span className="text-sm">
              Drop images here, tap to upload, or use camera
            </span>
          </div>
        )}
      </div>

      {/* Thumbnail grid */}
      {imageAttachments.length > 0 && (
        <div className="grid grid-cols-3 sm:grid-cols-4 md:grid-cols-5 lg:grid-cols-6 gap-2">
          {imageAttachments.map((att, i) => (
            <div key={att.id} className="relative group aspect-square">
              {/* eslint-disable-next-line @next/next/no-img-element */}
              <img
                src={att.fileUrl}
                alt={att.caption ?? att.fileName}
                className="w-full h-full object-cover rounded-lg bg-zinc-800 cursor-pointer"
                onClick={() => setLightboxIndex(i)}
              />
              {/* Overlay */}
              <div className="absolute inset-0 rounded-lg bg-black/0 group-hover:bg-black/40 transition-colors flex items-center justify-center">
                <div className="opacity-0 group-hover:opacity-100 flex gap-1 transition-opacity">
                  <button
                    onClick={() => setLightboxIndex(i)}
                    className="p-1.5 rounded bg-black/60 text-white hover:bg-black/80"
                  >
                    <ZoomIn className="h-3.5 w-3.5" />
                  </button>
                  <button
                    onClick={() => handleDelete(att.id)}
                    className="p-1.5 rounded bg-black/60 text-red-400 hover:bg-black/80"
                  >
                    <X className="h-3.5 w-3.5" />
                  </button>
                </div>
              </div>
              {/* Caption badge */}
              {att.caption && (
                <div className="absolute bottom-0 left-0 right-0 px-1 py-0.5 bg-black/60 rounded-b-lg text-[9px] text-zinc-300 truncate">
                  {att.caption}
                </div>
              )}
            </div>
          ))}
        </div>
      )}

      {/* Sketch button */}
      <button
        type="button"
        onClick={() => setShowSketch(true)}
        className="flex items-center gap-2 px-3 py-2 rounded-lg border border-zinc-700 hover:border-zinc-500 text-xs text-zinc-500 hover:text-zinc-300 transition-colors"
      >
        <Pencil className="h-3.5 w-3.5" />
        Add Sketch
      </button>

      {imageAttachments.length === 0 && !uploading && (
        <div className="flex items-center gap-2 text-zinc-600 text-xs py-2">
          <ImageIcon className="h-4 w-4" />
          No images yet
        </div>
      )}

      {/* Sketch pad */}
      {showSketch && (
        <SketchPad
          takeId={takeId}
          onSaved={(attachment) => onChange([...attachments, attachment])}
          onClose={() => setShowSketch(false)}
        />
      )}

      {/* Lightbox */}
      {lightboxIndex !== null && (
        <Lightbox
          attachments={imageAttachments}
          index={lightboxIndex}
          onClose={() => setLightboxIndex(null)}
        />
      )}
    </div>
  );
}