"use client";

import Image from "next/image";
import { useEffect, useState } from "react";
import { AudioLines, Images, PlayCircle } from "lucide-react";

import { Badge } from "@/components/ui/badge";
import { Card, CardContent } from "@/components/ui/card";
import { formatDateTime } from "@/lib/format";
import { getPostAuthor, getPostPreviewMedia, getUserLabel } from "@/lib/post-utils";
import type { ApiPost } from "@/types/api";

function formatDuration(durationSeconds?: number | null) {
  if (typeof durationSeconds !== "number" || !Number.isFinite(durationSeconds) || durationSeconds <= 0) {
    return null;
  }

  const minutes = Math.floor(durationSeconds / 60);
  const seconds = Math.floor(durationSeconds % 60);
  return `${minutes}:${seconds.toString().padStart(2, "0")}`;
}

export function PostPreviewCard({ post }: { post: ApiPost }) {
  const author = getPostAuthor(post);
  const media = getPostPreviewMedia(post);
  const likes = post.engagement?.likesCount ?? post.likesCount ?? 0;
  const comments = post.engagement?.commentsCount ?? post.commentsCount ?? 0;
  const shares = post.engagement?.shareCount ?? post.shareCount ?? 0;
  const waveformPeaks = Array.isArray(post.waveformPeaks) && post.waveformPeaks.length ? post.waveformPeaks : [18, 32, 24, 44, 28, 40, 22, 36, 26, 30];
  const durationLabel = formatDuration(post.durationSeconds);
  const [imageFailed, setImageFailed] = useState(false);
  const [sourceFailed, setSourceFailed] = useState(false);
  const [isVideoPlaying, setIsVideoPlaying] = useState(false);

  useEffect(() => {
    setImageFailed(false);
    setSourceFailed(false);
    setIsVideoPlaying(false);
  }, [media.url, media.sourceUrl]);

  const showAudioPreview = media.kind === "audio" && !!media.sourceUrl && !sourceFailed;
  const showVideoPreview =
    media.kind === "video" && !!media.sourceUrl && !sourceFailed && (isVideoPlaying || !media.url || imageFailed);
  const showImagePreview = !!media.url && !imageFailed && !(media.kind === "video" && isVideoPlaying);
  const showMediaShell = media.kind !== "text";
  const showUnavailable = !showImagePreview && !showVideoPreview && !showAudioPreview;

  return (
    <Card className="overflow-hidden border-border/70">
      <CardContent className="p-0">
        {showMediaShell ? (
          <div className="relative aspect-[16/9] border-b border-border/70 bg-secondary/30">
            {showImagePreview ? (
              <Image
                src={media.url}
                alt={post.content || post.postType || "post"}
                fill
                unoptimized
                loading="lazy"
                onError={() => setImageFailed(true)}
                className="object-cover"
              />
            ) : null}
            {showVideoPreview ? (
              <video
                src={media.sourceUrl}
                preload="metadata"
                controls={isVideoPlaying}
                autoPlay={isVideoPlaying}
                muted={!isVideoPlaying}
                playsInline
                onError={() => setSourceFailed(true)}
                className="h-full w-full object-cover"
              />
            ) : null}
            {showAudioPreview ? (
              <div className="absolute inset-0 flex flex-col justify-between bg-gradient-to-br from-secondary/70 via-background/60 to-secondary/80 p-5">
                <div className="flex items-center justify-between gap-3 text-sm text-foreground">
                  <div className="inline-flex items-center gap-2 rounded-full border border-border/60 bg-background/70 px-3 py-1">
                    <AudioLines className="h-4 w-4" />
                    <span>Audio preview</span>
                  </div>
                  {durationLabel ? <span className="text-xs text-muted-foreground">{durationLabel}</span> : null}
                </div>

                <div className="flex h-24 items-end justify-center gap-1.5 px-2">
                  {waveformPeaks.slice(0, 48).map((peak, index) => {
                    const safePeak = Number.isFinite(peak) ? Math.max(8, Math.min(100, peak)) : 20;
                    return (
                      <span
                        key={`${post._id}-peak-${index}`}
                        className="w-1.5 rounded-full bg-primary/80"
                        style={{ height: `${safePeak}%` }}
                      />
                    );
                  })}
                </div>

                <audio
                  src={media.sourceUrl}
                  preload="metadata"
                  controls
                  onError={() => setSourceFailed(true)}
                  className="w-full"
                />
              </div>
            ) : null}
            {showUnavailable ? (
              <div className="absolute inset-0 flex items-center justify-center px-4 text-center text-sm text-muted-foreground">
                Media preview unavailable
              </div>
            ) : null}
            <div className="absolute left-3 top-3 flex items-center gap-2">
              <Badge variant="warning">{post.postType ?? "post"}</Badge>
              {media.kind === "image" && media.count > 1 ? (
                <Badge variant="muted">
                  <Images className="mr-1 h-3 w-3" />
                  {media.count}
                </Badge>
              ) : null}
            </div>
            {media.kind === "video" && media.sourceUrl && !isVideoPlaying && !sourceFailed ? (
              <button
                type="button"
                aria-label="Play video"
                onClick={() => setIsVideoPlaying(true)}
                className="absolute inset-0 z-10 cursor-pointer bg-transparent"
              >
                <span className="sr-only">Play video</span>
              </button>
            ) : null}
            <div className="pointer-events-none absolute bottom-3 right-3 z-20 rounded-full border border-border/60 bg-background/85 p-2 text-foreground">
              {media.kind === "audio" ? <AudioLines className="h-4 w-4" /> : <PlayCircle className="h-4 w-4" />}
            </div>
          </div>
        ) : null}

        <div className="space-y-3 p-4">
          <div className="flex flex-wrap items-center gap-2">
            <Badge variant="muted">{post.visibility ?? "public"}</Badge>
            <Badge
              variant={
                post.moderationStatus === "hidden"
                  ? "danger"
                  : post.moderationStatus === "flagged"
                    ? "warning"
                    : "success"
              }
            >
              {post.moderationStatus ?? "active"}
            </Badge>
          </div>

          <div>
            <div className="text-sm font-semibold text-foreground">{getUserLabel(author)}</div>
            <div className="mt-1 text-xs text-muted-foreground">{formatDateTime(post.createdAt)}</div>
          </div>

          <p className="line-clamp-4 text-sm leading-6 text-foreground">
            {post.content?.trim() || "Media post without caption."}
          </p>

          <div className="flex flex-wrap gap-2 text-xs text-muted-foreground">
            <span>{likes} likes</span>
            <span>{comments} comments</span>
            <span>{shares} shares</span>
          </div>
        </div>
      </CardContent>
    </Card>
  );
}