/**
 * Cloud function: uploadManager
 * Signs Qiniu direct-upload tokens. File bytes are uploaded from the browser
 * directly to Qiniu, so the cloud function never handles large payloads.
 *
 * actions:
 *   createUploadToken -> { uploadUrl, token, key, url, mimeType, kind, expiresAt }
 */
async function handler(request, response) {
  try {
    const action = pickParam(request, 'action') || 'createUploadToken';

    if (action !== 'createUploadToken') {
      return response.json({ code: 400, success: false, error: `Unknown action: ${action}` });
    }

    const filename = String(pickParam(request, 'filename', 'fileName') || `asset-${Date.now()}`);
    const mimeType = String(pickParam(request, 'mimeType', 'contentType') || 'application/octet-stream');
    const requestedKind = String(pickParam(request, 'kind') || '').trim();
    const size = Number(pickParam(request, 'size') || 0);
    const kind = normalizeKind(requestedKind, mimeType);
    const key = buildDigitalHumanAssetKey(filename, kind);
    const { token, deadline } = await buildQiniuUploadToken(key);
    const url = `${QINIU_CDN_DOMAIN.replace(/\/$/, '')}/${key}`;

    response.json({
      code: 200,
      success: true,
      data: {
        uploadUrl: QINIU_UPLOAD_URL,
        token,
        key,
        url,
        mimeType,
        kind,
        size,
        expiresAt: deadline * 1000,
      },
    });
  } catch (error) {
    console.error('uploadManager failed:', error && error.message ? error.message : error);
    response.json({
      code: 500,
      success: false,
      error: error && error.message ? error.message : 'uploadManager failed',
    });
  }
}

const QINIU_ACCESS_KEY = readEnv('QINIU_AK') || readEnv('QINIU_ACCESS_KEY') || 'EXsA-z_n4LGmWrwC088bygcGJtAditnWQe2nH-ZE';
const QINIU_SECRET_KEY = readEnv('QINIU_SK') || readEnv('QINIU_SECRET_KEY') || 'HWTL92OL-Tup0-8ex8A9jnG3OaJzTxlF4OwiiDsX';
const QINIU_BUCKET = readEnv('QINIU_BUCKET') || 'nova-repos';
const QINIU_CDN_DOMAIN = readEnv('QINIU_CDN_DOMAIN') || 'https://repos.fmode.cn';
const QINIU_CDN_PREFIX = readEnv('QINIU_CDN_PREFIX') || 'x/openclaw-skills';
const QINIU_UPLOAD_URL = readEnv('QINIU_UPLOAD_URL') || 'https://up-z2.qiniup.com';

async function buildQiniuUploadToken(key) {
  if (!QINIU_ACCESS_KEY || !QINIU_SECRET_KEY) {
    throw new Error('Qiniu AK/SK is not configured');
  }

  const deadline = Math.floor(Date.now() / 1000) + 3600;
  const putPolicy = {
    scope: `${QINIU_BUCKET}:${key}`,
    deadline,
  };
  const encodedPutPolicy = toBase64Url(JSON.stringify(putPolicy));
  const sign = await hmacSha1Base64Url(QINIU_SECRET_KEY, encodedPutPolicy);

  return {
    token: `${QINIU_ACCESS_KEY}:${sign}:${encodedPutPolicy}`,
    deadline,
  };
}

function buildDigitalHumanAssetKey(fileName, kind) {
  const rawName = String(fileName || `asset-${Date.now()}`);
  const extMatch = rawName.match(/(\.[a-z0-9]+)$/i);
  const ext = extMatch ? extMatch[1].toLowerCase() : '';
  const safeExt = ext && /^[.a-z0-9]+$/i.test(ext) ? ext : '';
  const baseName = rawName
    .replace(/\\/g, '/')
    .split('/')
    .pop()
    .replace(/\.[^.]*$/, '')
    .replace(/[^a-zA-Z0-9_-]/g, '_') || `asset-${Date.now()}`;
  const date = new Date();
  const yyyy = date.getFullYear();
  const mm = String(date.getMonth() + 1).padStart(2, '0');
  const dd = String(date.getDate()).padStart(2, '0');
  const timestamp = `${yyyy}${mm}${dd}-${Date.now()}`;

  return `${QINIU_CDN_PREFIX}/digital-human/${kind}/${yyyy}${mm}${dd}/${timestamp}-${baseName}${safeExt}`;
}

function normalizeKind(kind, mimeType) {
  if (kind === 'audio' || kind === 'video' || kind === 'image') return kind;
  if (mimeType.startsWith('audio/')) return 'audio';
  if (mimeType.startsWith('video/')) return 'video';
  return 'image';
}

function toBase64Url(input) {
  return base64UrlEncode(bytesFromString(input));
}

function pickParam(request, ...names) {
  const sources = [request.params, request.body, request];
  for (const src of sources) {
    if (!src || typeof src !== 'object') continue;
    for (const n of names) {
      const v = src[n];
      if (v !== undefined && v !== null && v !== '') return v;
    }
  }
  return null;
}

function readEnv(name) {
  if (typeof process !== 'undefined' && process.env && process.env[name]) {
    return process.env[name];
  }
  return '';
}

async function hmacSha1Base64Url(secret, message) {
  const subtle = typeof globalThis !== 'undefined' && globalThis.crypto && globalThis.crypto.subtle;
  if (subtle && typeof TextEncoder !== 'undefined') {
    const encoder = new TextEncoder();
    const key = await subtle.importKey(
      'raw',
      encoder.encode(secret),
      { name: 'HMAC', hash: 'SHA-1' },
      false,
      ['sign']
    );
    const signature = await subtle.sign('HMAC', key, encoder.encode(message));
    return base64UrlEncode(new Uint8Array(signature));
  }

  if (typeof require === 'function') {
    const nodeCrypto = require('crypto');
    return nodeCrypto
      .createHmac('sha1', secret)
      .update(message)
      .digest('base64')
      .replace(/\+/g, '-')
      .replace(/\//g, '_');
  }

  return base64UrlEncode(hmacSha1Bytes(bytesFromString(secret), bytesFromString(message)));
}

function bytesFromString(input) {
  if (typeof TextEncoder !== 'undefined') {
    return new TextEncoder().encode(input);
  }
  if (typeof Buffer !== 'undefined') {
    return Buffer.from(input, 'utf8');
  }
  throw new Error('No UTF-8 encoder is available in this cloud runtime');
}

function base64UrlEncode(bytes) {
  let base64;
  if (typeof Buffer !== 'undefined') {
    base64 = Buffer.from(bytes).toString('base64');
  } else if (typeof btoa === 'function') {
    let binary = '';
    for (let i = 0; i < bytes.length; i++) {
      binary += String.fromCharCode(bytes[i]);
    }
    base64 = btoa(binary);
  } else {
    base64 = base64EncodeBytes(bytes);
  }

  return base64
    .replace(/\+/g, '-')
    .replace(/\//g, '_');
}

function base64EncodeBytes(bytes) {
  const alphabet = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/';
  let output = '';
  for (let i = 0; i < bytes.length; i += 3) {
    const b1 = bytes[i];
    const b2 = i + 1 < bytes.length ? bytes[i + 1] : 0;
    const b3 = i + 2 < bytes.length ? bytes[i + 2] : 0;
    const triplet = (b1 << 16) | (b2 << 8) | b3;

    output += alphabet[(triplet >> 18) & 0x3f];
    output += alphabet[(triplet >> 12) & 0x3f];
    output += i + 1 < bytes.length ? alphabet[(triplet >> 6) & 0x3f] : '=';
    output += i + 2 < bytes.length ? alphabet[triplet & 0x3f] : '=';
  }
  return output;
}

function hmacSha1Bytes(secretBytes, messageBytes) {
  const blockSize = 64;
  let key = toByteArray(secretBytes);
  if (key.length > blockSize) {
    key = sha1Bytes(key);
  }

  const paddedKey = new Uint8Array(blockSize);
  paddedKey.set(key);

  const innerPad = new Uint8Array(blockSize);
  const outerPad = new Uint8Array(blockSize);
  for (let i = 0; i < blockSize; i++) {
    innerPad[i] = paddedKey[i] ^ 0x36;
    outerPad[i] = paddedKey[i] ^ 0x5c;
  }

  return sha1Bytes(concatBytes(outerPad, sha1Bytes(concatBytes(innerPad, messageBytes))));
}

function sha1Bytes(inputBytes) {
  const bytes = toByteArray(inputBytes);
  const bitLength = bytes.length * 8;
  const paddedLength = (((bytes.length + 9 + 63) >> 6) << 6);
  const padded = new Uint8Array(paddedLength);
  padded.set(bytes);
  padded[bytes.length] = 0x80;

  const view = new DataView(padded.buffer);
  view.setUint32(paddedLength - 8, Math.floor(bitLength / 0x100000000), false);
  view.setUint32(paddedLength - 4, bitLength >>> 0, false);

  let h0 = 0x67452301;
  let h1 = 0xefcdab89;
  let h2 = 0x98badcfe;
  let h3 = 0x10325476;
  let h4 = 0xc3d2e1f0;
  const w = new Uint32Array(80);

  for (let offset = 0; offset < paddedLength; offset += 64) {
    for (let i = 0; i < 16; i++) {
      w[i] = view.getUint32(offset + i * 4, false);
    }
    for (let i = 16; i < 80; i++) {
      w[i] = rotateLeft(w[i - 3] ^ w[i - 8] ^ w[i - 14] ^ w[i - 16], 1);
    }

    let a = h0;
    let b = h1;
    let c = h2;
    let d = h3;
    let e = h4;

    for (let i = 0; i < 80; i++) {
      let f;
      let k;
      if (i < 20) {
        f = (b & c) | (~b & d);
        k = 0x5a827999;
      } else if (i < 40) {
        f = b ^ c ^ d;
        k = 0x6ed9eba1;
      } else if (i < 60) {
        f = (b & c) | (b & d) | (c & d);
        k = 0x8f1bbcdc;
      } else {
        f = b ^ c ^ d;
        k = 0xca62c1d6;
      }

      const temp = (rotateLeft(a, 5) + f + e + k + w[i]) >>> 0;
      e = d;
      d = c;
      c = rotateLeft(b, 30);
      b = a;
      a = temp;
    }

    h0 = (h0 + a) >>> 0;
    h1 = (h1 + b) >>> 0;
    h2 = (h2 + c) >>> 0;
    h3 = (h3 + d) >>> 0;
    h4 = (h4 + e) >>> 0;
  }

  const output = new Uint8Array(20);
  const outputView = new DataView(output.buffer);
  outputView.setUint32(0, h0, false);
  outputView.setUint32(4, h1, false);
  outputView.setUint32(8, h2, false);
  outputView.setUint32(12, h3, false);
  outputView.setUint32(16, h4, false);
  return output;
}

function concatBytes(a, b) {
  const left = toByteArray(a);
  const right = toByteArray(b);
  const out = new Uint8Array(left.length + right.length);
  out.set(left);
  out.set(right, left.length);
  return out;
}

function toByteArray(bytes) {
  return bytes instanceof Uint8Array ? bytes : new Uint8Array(bytes);
}

function rotateLeft(value, bits) {
  return ((value << bits) | (value >>> (32 - bits))) >>> 0;
}