const fs = require('fs');
const path = require('path');
const {
  uploadTemplateFile,
  uploadTemplateAsset,
  templateAssetsBaseUrl,
} = require('../../src/utils/s3MicrositeV2');
const { parseTemplateSchema } = require('../../src/utils/templateSchema');
require('../../src/models/Organization');
require('../../src/models/User');
const MicrositeV2Template = require('../../src/models/MicrositeV2Template');
const { getGlobalMicrositeV2Template } = require('../../src/config/globalMicrositeV2Templates');

const BACKEND_ROOT = path.join(__dirname, '..', '..');
const TEMPLATES_ROOT = path.join(BACKEND_ROOT, 'microsite-v2-templates');

function walkDir(dir, base = dir) {
  const files = [];
  if (!fs.existsSync(dir)) return files;
  for (const name of fs.readdirSync(dir)) {
    const full = path.join(dir, name);
    const stat = fs.statSync(full);
    if (stat.isDirectory()) {
      files.push(...walkDir(full, base));
    } else {
      files.push({ full, rel: path.relative(base, full).replace(/\\/g, '/') });
    }
  }
  return files;
}

function mimeFor(filePath) {
  if (filePath.endsWith('.css')) return 'text/css';
  if (filePath.endsWith('.js')) return 'application/javascript';
  if (filePath.endsWith('.woff')) return 'font/woff';
  if (filePath.endsWith('.woff2')) return 'font/woff2';
  if (filePath.endsWith('.ttf')) return 'font/ttf';
  if (filePath.endsWith('.eot')) return 'application/vnd.ms-fontobject';
  if (filePath.endsWith('.png')) return 'image/png';
  if (filePath.endsWith('.jpg') || filePath.endsWith('.jpeg')) return 'image/jpeg';
  if (filePath.endsWith('.svg')) return 'image/svg+xml';
  if (filePath.endsWith('.gif')) return 'image/gif';
  if (filePath.endsWith('.webp')) return 'image/webp';
  return 'application/octet-stream';
}

/**
 * Theme packs often bake cache-busters into filenames (LineIcons.woff?y2l643,
 * fontawesome-webfont.eot?v=4.7.0). Strip those so S3 keys match clean @font-face URLs.
 */
function normalizeAssetRelPath(rel) {
  const base = String(rel).replace(/\\/g, '/');
  // Strip query suffix from any path segment (literal ? in filename or ?query).
  return base.replace(/(\.(?:woff2?|ttf|eot|svg|otf))\?[^/]*$/i, '$1');
}

function svgPlaceholder(label, color) {
  const safeLabel = String(label || 'Template').slice(0, 40);
  const fill = String(color || '#5c6ac4');
  return Buffer.from(
    `<svg xmlns="http://www.w3.org/2000/svg" width="400" height="240"><rect fill="${fill}" width="400" height="240"/><text x="50%" y="50%" fill="#fff" text-anchor="middle" dy=".3em" font-family="sans-serif" font-size="22">${safeLabel}</text></svg>`,
  );
}

/**
 * Upload template files to S3 and upsert MicrositeV2Template row.
 * @param {{ slug: string, user: import('mongoose').Document, dbOnly?: boolean }} opts
 */
async function seedOneMicrositeV2Template({ slug, user, dbOnly = false }) {
  const def = getGlobalMicrositeV2Template(slug);
  if (!def) {
    throw new Error(`Unknown global microsite template slug: ${slug}`);
  }

  const templateDir = path.join(TEMPLATES_ROOT, def.slug);
  const templateAssets = path.join(templateDir, 'assets');
  const htmlPath = path.join(templateDir, 'template.html');
  const jsonPath = path.join(templateDir, 'template.json');
  if (!fs.existsSync(htmlPath) || !fs.existsSync(jsonPath)) {
    throw new Error(`Missing template.html or template.json in ${templateDir}`);
  }

  const htmlBuf = fs.readFileSync(htmlPath);
  const jsonBuf = fs.readFileSync(jsonPath);
  const schema = parseTemplateSchema(jsonBuf);

  let htmlS3Key;
  let schemaS3Key;
  let thumbnailUrl;
  let assetsBaseUrl = templateAssetsBaseUrl(def.slug);

  if (!dbOnly && process.env.AWS_BUCKET) {
    console.log(`[${def.slug}] Uploading template.html...`);
    const htmlUp = await uploadTemplateFile(def.slug, 'template.html', htmlBuf, 'text/html; charset=utf-8');
    htmlS3Key = htmlUp.s3Key;

    console.log(`[${def.slug}] Uploading template.json...`);
    const jsonUp = await uploadTemplateFile(def.slug, 'template.json', jsonBuf, 'application/json');
    schemaS3Key = jsonUp.s3Key;

    for (const rel of def.thumbnailCandidates || []) {
      const tp = path.join(templateDir, rel);
      if (!fs.existsSync(tp)) continue;
      const ext = path.extname(tp).slice(1) || 'jpg';
      const thumbUp = await uploadTemplateFile(
        def.slug,
        `thumbnail.${ext}`,
        fs.readFileSync(tp),
        `image/${ext === 'jpg' ? 'jpeg' : ext}`,
      );
      thumbnailUrl = thumbUp.url;
      break;
    }
    if (!thumbnailUrl) {
      const thumbUp = await uploadTemplateFile(
        def.slug,
        'thumbnail.svg',
        svgPlaceholder(def.placeholderSvgLabel || def.name, def.placeholderSvgColor),
        'image/svg+xml',
      );
      thumbnailUrl = thumbUp.url;
    }

    const assetRoots = [];
    if (fs.existsSync(templateAssets)) assetRoots.push(templateAssets);
    for (const externalRel of def.externalAssetRoots || []) {
      const externalRoot = path.isAbsolute(externalRel)
        ? externalRel
        : path.join(BACKEND_ROOT, '..', externalRel);
      if (fs.existsSync(externalRoot)) assetRoots.push(externalRoot);
    }

    for (const root of assetRoots) {
      console.log(`[${def.slug}] Uploading assets from ${root}...`);
      for (const { full, rel } of walkDir(root)) {
        const normalizedRel = normalizeAssetRelPath(rel);
        if (normalizedRel !== rel && fs.existsSync(path.join(root, normalizedRel))) {
          continue;
        }
        await uploadTemplateAsset(def.slug, normalizedRel, fs.readFileSync(full), mimeFor(normalizedRel));
      }
    }

    assetsBaseUrl = templateAssetsBaseUrl(def.slug);
    console.log(`[${def.slug}] S3 upload complete.`);
  } else {
    console.log(`[${def.slug}] Skipping S3 upload (--db-only or AWS_BUCKET not set).`);
  }

  const existing = await MicrositeV2Template.findOne({ slug: def.slug }).select('_id htmlS3Key schemaS3Key thumbnailUrl').lean();
  const doc = {
    slug: def.slug,
    name: def.name,
    description: def.description,
    thumbnailUrl: thumbnailUrl || existing?.thumbnailUrl || '',
    htmlS3Key: htmlS3Key || existing?.htmlS3Key || '',
    schemaS3Key: schemaS3Key || existing?.schemaS3Key || '',
    schema,
    assetsBaseUrl,
    assetsS3Prefix: `templates/${def.slug}/assets`,
    isActive: Boolean((htmlS3Key || existing?.htmlS3Key) && (schemaS3Key || existing?.schemaS3Key)),
    version: schema.version || 1,
    createdBy: user._id,
  };

  const now = new Date();
  const setFields = {
    ...doc,
    updatedAt: now,
  };

  await MicrositeV2Template.collection.updateOne(
    { slug: def.slug },
    {
      $set: setFields,
      $setOnInsert: {
        allowedOrganizations: [],
        visibility: 'public',
        createdAt: now,
      },
    },
    { upsert: true },
  );

  const saved = await MicrositeV2Template.findOne({ slug: def.slug }).select('_id slug').lean();
  console.log(
    `[${def.slug}] ${existing ? 'Updated' : 'Created'} MicrositeV2Template: ${saved?._id}`,
  );
  return saved;
}

module.exports = {
  seedOneMicrositeV2Template,
};