import { auth } from "@/lib/auth";
import { prisma } from "@/lib/prisma";

interface LikedEntry {
  assetId: string;
  filePath: string;
  fileName: string;
  dimensions: string | null;
  platform: string | null;
  style: string | null; // "with-people" | "without-people" | null
  timestamp: string;
}

interface DislikedEntry {
  assetId: string;
  reason: string;
  fileName: string;
  dimensions: string | null;
  platform: string | null;
  style: string | null;
  timestamp: string;
}

interface StylePreferences {
  liked: LikedEntry[];
  disliked: DislikedEntry[];
}

function parsePreferences(raw: string | null): StylePreferences {
  if (!raw) return { liked: [], disliked: [] };
  try {
    const parsed = JSON.parse(raw);
    return {
      liked: Array.isArray(parsed.liked) ? parsed.liked : [],
      disliked: Array.isArray(parsed.disliked) ? parsed.disliked : [],
    };
  } catch {
    return { liked: [], disliked: [] };
  }
}

export async function GET(
  _request: Request,
  { params }: { params: Promise<{ id: string }> }
) {
  const session = await auth();
  if (!session) return new Response("Unauthorized", { status: 401 });

  const { id } = await params;

  const asset = await prisma.asset.findUnique({
    where: { id },
    include: { campaign: { include: { app: true } } },
  });

  if (!asset) return Response.json({ error: "Not found" }, { status: 404 });

  const app = asset.campaign?.app;
  if (!app) return Response.json({ vote: null });

  const prefs = parsePreferences(app.stylePreferences);
  const isLiked = prefs.liked.some((e) => e.assetId === id);
  const isDisliked = prefs.disliked.some((e) => e.assetId === id);

  return Response.json({ vote: isLiked ? "up" : isDisliked ? "down" : null });
}

export async function POST(
  request: Request,
  { params }: { params: Promise<{ id: string }> }
) {
  const session = await auth();
  if (!session) return new Response("Unauthorized", { status: 401 });

  const { id } = await params;
  const body = await request.json();
  const { vote, reason } = body as { vote: "up" | "down"; reason?: string };

  if (vote !== "up" && vote !== "down") {
    return Response.json({ error: "vote must be 'up' or 'down'" }, { status: 400 });
  }

  const asset = await prisma.asset.findUnique({
    where: { id },
    include: { campaign: { include: { app: true } } },
  });

  if (!asset) return Response.json({ error: "Not found" }, { status: 404 });

  const app = asset.campaign?.app;
  if (!app) {
    return Response.json({ error: "Asset has no associated app" }, { status: 400 });
  }

  // Extract style from asset metadata (set by ad_manifest.json during generation)
  let assetStyle: string | null = null;
  if (asset.metadata) {
    try {
      const meta = JSON.parse(asset.metadata);
      if (meta.style === "with-people" || meta.style === "without-people") {
        assetStyle = meta.style;
      }
    } catch { /* metadata isn't JSON or has no style */ }
  }

  const prefs = parsePreferences(app.stylePreferences);

  // Remove from both lists first (clean slate for this asset)
  prefs.liked = prefs.liked.filter((e) => e.assetId !== id);
  prefs.disliked = prefs.disliked.filter((e) => e.assetId !== id);

  // Check if this was already the active vote (toggle off)
  const wasLiked = parsePreferences(app.stylePreferences).liked.some((e) => e.assetId === id);
  const wasDisliked = parsePreferences(app.stylePreferences).disliked.some((e) => e.assetId === id);
  const isToggleOff = (vote === "up" && wasLiked) || (vote === "down" && wasDisliked);

  if (!isToggleOff) {
    if (vote === "up") {
      prefs.liked.push({
        assetId: id,
        filePath: asset.filePath,
        fileName: asset.fileName,
        dimensions: asset.dimensions || null,
        platform: asset.platform || null,
        style: assetStyle,
        timestamp: new Date().toISOString(),
      });
      // Keep max ~10 liked
      if (prefs.liked.length > 10) {
        prefs.liked = prefs.liked.slice(-10);
      }
    } else {
      prefs.disliked.push({
        assetId: id,
        reason: reason || "Not preferred",
        fileName: asset.fileName,
        dimensions: asset.dimensions || null,
        platform: asset.platform || null,
        style: assetStyle,
        timestamp: new Date().toISOString(),
      });
      // Keep max ~20 disliked
      if (prefs.disliked.length > 20) {
        prefs.disliked = prefs.disliked.slice(-20);
      }
    }
  }

  await prisma.app.update({
    where: { id: app.id },
    data: { stylePreferences: JSON.stringify(prefs) },
  });

  const newVote = isToggleOff ? null : vote;
  return Response.json({ vote: newVote });
}