import path from "path";
import { mkdirSync } from "fs";
import { runAgentStep } from "./claude";
import { getAllSettings } from "./settings";

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

const PLATFORM_FORMATS: Record<string, { width: number; height: number; label: string; ratio: string }> = {
  "instagram-feed": { width: 1080, height: 1080, label: "Instagram Feed", ratio: "1:1" },
  "instagram-stories": { width: 1080, height: 1920, label: "Instagram Stories", ratio: "9:16" },
  tiktok: { width: 1080, height: 1920, label: "TikTok", ratio: "9:16" },
  "nextdoor-spotlight": { width: 1200, height: 1200, label: "Nextdoor Spotlight", ratio: "1:1" },
  "nextdoor-display": { width: 1200, height: 628, label: "Nextdoor Display", ratio: "191:100" },
};

export function getAvailableFormats(currentDimensions: string | null): string[] {
  return Object.keys(PLATFORM_FORMATS).filter((key) => {
    const fmt = PLATFORM_FORMATS[key];
    return `${fmt.width}x${fmt.height}` !== currentDimensions;
  });
}

export function getPlatformFormat(key: string) {
  return PLATFORM_FORMATS[key] || null;
}

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

/**
 * Repurpose an image to target platform formats using Gemini via Claude CLI.
 * Claude analyzes the original ad and instructs Gemini to regenerate it
 * at the new dimensions with proper layout adaptation.
 */
export async function repurposeImage(
  sourcePath: string,
  sourceDimensions: string | null,
  targetFormats: string[],
  outputDir: string
): Promise<Array<{ filePath: string; fileName: string; dimensions: string; platform: string }>> {
  mkdirSync(path.join(PIPELINE_ROOT, outputDir), { recursive: true });

  const sourceBase = path.basename(sourcePath, path.extname(sourcePath));
  const env = await loadPipelineEnv();

  const formatInstructions = targetFormats.map((key) => {
    const fmt = PLATFORM_FORMATS[key];
    if (!fmt) return null;
    const fileName = `${sourceBase}_${key}_${fmt.width}x${fmt.height}.png`;
    return { key, fmt, fileName };
  }).filter(Boolean) as Array<{ key: string; fmt: typeof PLATFORM_FORMATS[string]; fileName: string }>;

  // Resolve absolute paths so the agent doesn't have to guess
  const absPipelineRoot = path.resolve(PIPELINE_ROOT);
  const absSourcePath = path.join(absPipelineRoot, sourcePath);

  const prompt = `You are an ad creative reformatter. Your job is to take an existing ad image and recreate it at different dimensions, keeping ALL the same content — same text, same layout structure, same colors, same branding, same imagery — but properly recomposed for the new aspect ratio.

## Source Ad
- File: ${absSourcePath}
- Current dimensions: ${sourceDimensions || "unknown"}

First, use the Read tool to look at the source image so you can see exactly what it contains.

## What To Do

For EACH target format below, do this EXACT sequence:
1. Call mcp__nanobanana__set_aspect_ratio with the correct ratio string
2. Call mcp__nanobanana__gemini_generate_image with:
   - reference_images: ["${absSourcePath}"]
   - prompt: Describe in detail everything you see in the source ad — the exact headline text, body text, phone mockup, app screenshot, app icon, CTA button text and color, brand name, background color and style. Then say: "Recreate this ad with all these elements recomposed for the new aspect ratio. Keep all text word-for-word identical. Adapt the layout naturally for the new dimensions."
   - output_path: the ABSOLUTE output path shown below

## Target Formats

${formatInstructions.map((f) => `### ${f.fmt.label} (${f.fmt.width}x${f.fmt.height})
- Aspect ratio for set_aspect_ratio: "${f.fmt.ratio}"
- output_path: "${path.join(absPipelineRoot, outputDir, f.fileName)}"`).join("\n\n")}

CRITICAL RULES:
- You MUST read the source image first to see what it contains
- Every piece of text from the original MUST appear in the output, word for word
- The visual style, colors, and branding must match exactly
- The layout should be ADAPTED for the new dimensions, not just cropped or padded
- Use the exact output_path values above — they are absolute paths
- The reference_images array must use the absolute source path above`;

  await runAgentStep("repurpose-adapter", prompt, PIPELINE_ROOT, env);

  // Return expected output info — the agent writes files to disk
  return formatInstructions.map((f) => ({
    filePath: path.join(outputDir, f.fileName),
    fileName: f.fileName,
    dimensions: `${f.fmt.width}x${f.fmt.height}`,
    platform: f.key.split("-")[0],
  }));
}

/**
 * Re-tone a caption for a different platform using Claude CLI.
 */
export async function retoneCaption(
  originalCaption: string,
  originalPlatform: string,
  targetPlatform: string
): Promise<string> {
  const prompt = `You are a social media copywriter. Adapt this ${originalPlatform} caption for ${targetPlatform}.

Original caption:
${originalCaption}

Rules:
- ${targetPlatform === "tiktok" ? "Raw, authentic tone. Short. Trending hashtags. Hook in first line." : ""}
- ${targetPlatform === "instagram" ? "Polished, aspirational. Hook → Value → CTA → Hashtags. 150-300 chars." : ""}
- ${targetPlatform === "nextdoor" ? "Warm, neighborly. No hashtags. Reference local/community context." : ""}
- Keep the core message but match the platform's voice.
- Return ONLY the new caption text, nothing else.`;

  const { output } = await runAgentStep("caption-retone", prompt, PIPELINE_ROOT, {});
  return output.trim();
}