import { mkdirSync } from "fs";
import path from "path";
import { prisma } from "./prisma";
import { runAgentStep } from "./claude";
import { getAllSettings } from "./settings";
import { scanOutputDirectory } from "./scanner";
import type { AppConfig } from "./claude";

const PIPELINE_ROOT = process.env.PIPELINE_ROOT || path.join(process.cwd(), "pipeline");

interface VariationRequest {
  assetId: string;
  count: number;
  appConfig?: AppConfig;
}

async function loadPipelineEnv(): Promise<Record<string, string>> {
  const settings = await getAllSettings();
  const env: Record<string, string> = {};
  if (settings.TAVILY_API_KEY) env.TAVILY_API_KEY = settings.TAVILY_API_KEY;
  if (settings.GEMINI_API_KEY) env.GEMINI_API_KEY = settings.GEMINI_API_KEY;
  return env;
}

/**
 * Extract the "DNA" from an asset — hook, CTA, visual style, platform, dimensions.
 */
function extractAssetDNA(asset: {
  metadata: string | null;
  platform: string | null;
  dimensions: string | null;
  filePath: string;
  type: string;
}) {
  const meta = asset.metadata ? JSON.parse(asset.metadata) : {};
  return {
    hook: meta.hook || meta.headline || meta.hookText || null,
    caption: meta.caption || null,
    cta: meta.cta || meta.ctaText || null,
    style: meta.style || null,
    platform: asset.platform,
    dimensions: asset.dimensions,
    type: asset.type,
    isGemini: asset.filePath.toLowerCase().includes("/gemini/"),
    isPoster: asset.filePath.toLowerCase().includes("/posters/"),
  };
}

/**
 * Build a prompt for the ad-creative-designer to generate variations of a winning asset.
 */
function buildVariationPrompt(
  dna: ReturnType<typeof extractAssetDNA>,
  sourceFilePath: string,
  count: number,
  outputDir: string,
  appConfig?: AppConfig
): string {
  const appName = appConfig?.name ?? "the app";
  const primaryColor = appConfig?.primaryColor ?? "#0079FF";
  const accentColor = appConfig?.accentColor ?? "#FF9400";
  const assetsDir = appConfig?.assetsDir ?? "assets";

  return `You are the Ad Creative Designer agent generating VARIATIONS of a winning ad.

## Source Asset (the winner to riff on)
- File: ${sourceFilePath}
- Platform: ${dna.platform || "instagram"}
- Dimensions: ${dna.dimensions || "1080x1920"}
- Hook: "${dna.hook || "Unknown"}"
- CTA: "${dna.cta || "Download Free"}"
- Style: ${dna.isGemini ? "Gemini AI-generated" : dna.isPoster ? "Canvas Design poster" : "Unknown"}

## Your Task
Generate ${count} NEW variations that keep the same emotional pattern as the winning hook but explore different angles.

Rules:
- Same platform and dimensions as the source
- Same visual style (${dna.isGemini ? "Gemini AI photo-realistic" : "Canvas Design poster art"})
- Same CTA pattern
- DIFFERENT hook text — same emotional structure, different scenarios
- Brand colors: ${primaryColor} (primary), ${accentColor} (accent)
- App name: ${appName}
- App icon: ${assetsDir}/icon.png — must appear in every ad

${dna.isGemini ? `Use mcp__nanobanana__gemini_generate_image for each variation.
Use the source ad as a reference_image so Gemini keeps visual consistency.
Reference image path: \${CWD}/${sourceFilePath}` : `Create each poster programmatically using Playwright (HTML → PNG).
Match the visual language of the source poster.`}

Save all outputs to: ${outputDir}/
Name files: variation_${dna.platform || "ig"}_${count > 1 ? "{n}" : "1"}_${dna.dimensions || "1080x1920"}.png
Save a manifest: ${outputDir}/variation_manifest.json with fields: fileName, hook, platform, dimensions, parentFile.

## Also Generate Copy
For each variation, write a platform-tuned caption.
Save to: ${outputDir}/captions.json as an array of { hook, caption, platform, fileName }.`;
}

/**
 * Spawn variations of a winning asset.
 * Runs ad-creative-designer agent with a focused variation prompt.
 */
export async function spawnVariations(request: VariationRequest) {
  const asset = await prisma.asset.findUnique({
    where: { id: request.assetId },
    include: { campaign: true },
  });

  if (!asset) throw new Error("Asset not found");
  if (!asset.campaign) throw new Error("Asset has no campaign");

  const dna = extractAssetDNA(asset);
  const dateStr = new Date().toISOString().slice(0, 10).replace(/-/g, "");
  const outputDir = `outputs/variations_${asset.id.slice(0, 8)}_${dateStr}`;

  mkdirSync(path.join(PIPELINE_ROOT, outputDir), { recursive: true });

  const prompt = buildVariationPrompt(
    dna,
    asset.filePath,
    request.count,
    outputDir,
    request.appConfig
  );

  const env = await loadPipelineEnv();

  const { output } = await runAgentStep("ad-creative-designer", prompt, PIPELINE_ROOT, env);

  // Scan for generated assets
  const scanResult = await scanOutputDirectory(asset.campaignId, outputDir, PIPELINE_ROOT);

  // Link new assets to the parent
  const newAssets = await prisma.asset.findMany({
    where: {
      campaignId: asset.campaignId,
      filePath: { startsWith: outputDir },
      parentAssetId: null,
    },
  });

  for (const newAsset of newAssets) {
    await prisma.asset.update({
      where: { id: newAsset.id },
      data: { parentAssetId: asset.id },
    });
  }

  return {
    output: output.slice(0, 500),
    outputDir,
    scanned: scanResult.scanned,
    created: scanResult.created,
    parentAssetId: asset.id,
  };
}