"use client";

import { Upload, X } from "lucide-react";
import { useCallback, useEffect, useMemo, useRef, useState } from "react";
import { Button } from "@/components/ui/button";
import { resizeImageToDataURL } from "@/lib/image/resize";
import { cn } from "@/lib/utils";

export interface ProcessedImage {
  id: string;
  originalName: string;
  previewUrl: string;
  dataUrl: string;
  mimeType: string;
  width: number;
  height: number;
}

interface ItemImageCaptureProps {
  maxImages?: number;
  className?: string;
  onImagesChange?: (images: ProcessedImage[]) => void;
}

export function ItemImageCapture({
  maxImages = 2,
  className,
  onImagesChange,
}: ItemImageCaptureProps) {
  const generateId = useCallback(() => {
    if (typeof crypto !== "undefined" && "randomUUID" in crypto) {
      return crypto.randomUUID();
    }
    return `img-${Date.now()}-${Math.random().toString(16).slice(2)}`;
  }, []);

  const [images, setImages] = useState<ProcessedImage[]>([]);
  const inputRef = useRef<HTMLInputElement>(null);
  const previewUrlsRef = useRef<Set<string>>(new Set());

  const updateImages = useCallback(
    (next: ProcessedImage[]) => {
      setImages(next);
      onImagesChange?.(next);
    },
    [onImagesChange],
  );

  const handleFiles = useCallback(
    async (files: FileList | File[]) => {
      const fileArray = Array.from(files).slice(0, maxImages - images.length);
      if (fileArray.length === 0) return;

      const processed: ProcessedImage[] = [];

      for (const file of fileArray) {
        if (!file.type.startsWith("image/")) continue;
        try {
          const { dataUrl, width, height } = await resizeImageToDataURL(file, {
            mimeType: file.type === "image/png" ? "image/png" : "image/jpeg",
          });

          const previewUrl = URL.createObjectURL(file);
          previewUrlsRef.current.add(previewUrl);

          processed.push({
            id: generateId(),
            originalName: file.name,
            previewUrl,
            dataUrl,
            mimeType: file.type === "image/png" ? "image/png" : "image/jpeg",
            width,
            height,
          });
        } catch (error) {
          console.error("Falha ao processar imagem", error);
        }
      }

      if (processed.length > 0) {
        updateImages([...images, ...processed].slice(0, maxImages));
      }
    },
    [generateId, images, maxImages, updateImages],
  );

  const handleDrop = useCallback(
    async (event: React.DragEvent<HTMLDivElement>) => {
      event.preventDefault();
      if (event.dataTransfer.files?.length) {
        await handleFiles(event.dataTransfer.files);
      }
    },
    [handleFiles],
  );

  const onPaste = useCallback(
    async (event: React.ClipboardEvent<HTMLDivElement>) => {
      const items = event.clipboardData?.items;
      if (!items) return;
      const files: File[] = [];
      for (const item of items) {
        if (item.type.startsWith("image/")) {
          const file = item.getAsFile();
          if (file) files.push(file);
        }
      }
      if (files.length) {
        await handleFiles(files);
      }
    },
    [handleFiles],
  );

  const removeImage = useCallback(
    (id: string) => {
      const nextImage = images.find((image) => image.id === id);
      if (nextImage) {
        URL.revokeObjectURL(nextImage.previewUrl);
        previewUrlsRef.current.delete(nextImage.previewUrl);
      }
      const next = images.filter((image) => image.id !== id);
      updateImages(next);
    },
    [images, updateImages],
  );

  const canAddMore = images.length < maxImages;

  const dropLabel = useMemo(() => {
    if (images.length === 0) {
      return "Arraste, cole (Ctrl+V) ou escolha imagens";
    }
    if (canAddMore) {
      return "Adicione mais imagens ou cole via Ctrl+V";
    }
    return "Limite máximo de imagens atingido";
  }, [images.length, canAddMore]);

  useEffect(
    () => () => {
      previewUrlsRef.current.forEach((url) => URL.revokeObjectURL(url));
      previewUrlsRef.current.clear();
    },
    [],
  );

  return (
    <div className={cn("space-y-4", className)}>
      <div
        className={cn(
          "rounded-lg border-2 border-dashed border-muted-foreground/40 bg-muted/40 p-6 text-center transition-colors",
          canAddMore ? "hover:border-primary" : "opacity-70",
        )}
        onDragOver={(event) => {
          event.preventDefault();
          event.dataTransfer.dropEffect = "copy";
        }}
        onDrop={handleDrop}
        onPaste={onPaste}
        role="presentation"
      >
        <div className="flex flex-col items-center gap-3">
          <Upload className="h-8 w-8 text-muted-foreground" />
          <p className="text-sm text-muted-foreground">{dropLabel}</p>
          <Button
            type="button"
            variant="outline"
            onClick={() => inputRef.current?.click()}
            disabled={!canAddMore}
          >
            Selecionar arquivo
          </Button>
          <input
            ref={inputRef}
            type="file"
            accept="image/*"
            multiple
            className="hidden"
            onChange={async (event) => {
              if (event.target.files?.length) {
                await handleFiles(event.target.files);
                event.target.value = "";
              }
            }}
          />
        </div>
      </div>

      {images.length > 0 && (
        <div className="grid gap-3 sm:grid-cols-2">
          {images.map((image) => (
            <div
              key={image.id}
              className="relative overflow-hidden rounded-md border bg-background shadow-sm"
            >
              <button
                type="button"
                className="absolute right-2 top-2 rounded-full bg-background/80 p-1 text-muted-foreground transition hover:bg-destructive hover:text-destructive-foreground"
                onClick={() => removeImage(image.id)}
                aria-label="Remover imagem"
              >
                <X className="h-4 w-4" />
              </button>
              <span className="absolute left-2 top-2 inline-flex items-center gap-1 rounded-full bg-emerald-600/90 px-2 py-0.5 text-[11px] text-white">
                <span className="h-1.5 w-1.5 rounded-full bg-white" />
                Pronta
              </span>
              <img
                src={image.previewUrl}
                alt={image.originalName}
                className="h-48 w-full object-cover"
              />
              <div className="border-t p-3 text-xs text-muted-foreground">
                <p className="font-medium">{image.originalName}</p>
                <p>
                  {image.width}×{image.height}px ·{" "}
                  {Math.round((image.dataUrl.length * 3) / 4 / 1024)}KB
                </p>
              </div>
            </div>
          ))}
        </div>
      )}
    </div>
  );
}