import fs from 'fs';
import path from 'path';
import os from 'os';
import { readAuthFile } from './opencode-auth.js';

const OPENCODE_CONFIG_DIR = path.join(os.homedir(), '.config', 'opencode');
const OPENCODE_DATA_DIR = path.join(os.homedir(), '.local', 'share', 'opencode');


const ANTIGRAVITY_ACCOUNTS_PATHS = [
  path.join(OPENCODE_CONFIG_DIR, 'antigravity-accounts.json'),
  path.join(OPENCODE_DATA_DIR, 'antigravity-accounts.json')
];

const readJsonFile = (filePath) => {
  if (!fs.existsSync(filePath)) {
    return null;
  }
  try {
    const raw = fs.readFileSync(filePath, 'utf8');
    const trimmed = raw.trim();
    if (!trimmed) return null;
    return JSON.parse(trimmed);
  } catch (error) {
    console.warn(`Failed to read JSON file: ${filePath}`, error);
    return null;
  }
};

const getAuthEntry = (auth, aliases) => {
  for (const alias of aliases) {
    if (auth[alias]) {
      return auth[alias];
    }
  }
  return null;
};

const normalizeAuthEntry = (entry) => {
  if (!entry) return null;
  if (typeof entry === 'string') {
    return { token: entry };
  }
  if (typeof entry === 'object') {
    return entry;
  }
  return null;
};

const asObject = (value) => (value && typeof value === 'object' ? value : null);

const asNonEmptyString = (value) => {
  if (typeof value !== 'string') return null;
  const trimmed = value.trim();
  return trimmed ? trimmed : null;
};

const parseGoogleRefreshToken = (rawRefreshToken) => {
  const refreshToken = asNonEmptyString(rawRefreshToken);
  if (!refreshToken) {
    return { refreshToken: null, projectId: null, managedProjectId: null };
  }

  const [rawToken = '', rawProject = '', rawManagedProject = ''] = refreshToken.split('|');
  return {
    refreshToken: asNonEmptyString(rawToken),
    projectId: asNonEmptyString(rawProject),
    managedProjectId: asNonEmptyString(rawManagedProject)
  };
};

const toNumber = (value) => {
  if (typeof value === 'number' && Number.isFinite(value)) {
    return value;
  }
  if (typeof value === 'string') {
    const parsed = Number(value);
    return Number.isFinite(parsed) ? parsed : null;
  }
  return null;
};

const toTimestamp = (value) => {
  if (!value) return null;
  if (typeof value === 'number') {
    return value < 1_000_000_000_000 ? value * 1000 : value;
  }
  if (typeof value === 'string') {
    const parsed = Date.parse(value);
    return Number.isNaN(parsed) ? null : parsed;
  }
  return null;
};

const formatResetTime = (timestamp) => {
  try {
    const resetDate = new Date(timestamp);
    const now = new Date();
    const isToday = resetDate.toDateString() === now.toDateString();
    
    if (isToday) {
      // Same day: show time only (e.g., "9:56 PM")
      return resetDate.toLocaleTimeString(undefined, {
        hour: 'numeric',
        minute: '2-digit'
      });
    }
    
    // Different day: show date + weekday + time (e.g., "Feb 2, Sun 9:56 PM")
    return resetDate.toLocaleString(undefined, {
      month: 'short',
      day: 'numeric',
      weekday: 'short',
      hour: 'numeric',
      minute: '2-digit'
    });
  } catch {
    return null;
  }
};

const calculateResetAfterSeconds = (resetAt) => {
  if (!resetAt) return null;
  const delta = Math.floor((resetAt - Date.now()) / 1000);
  return delta < 0 ? 0 : delta;
};

const toUsageWindow = ({ usedPercent, windowSeconds, resetAt, valueLabel }) => {
  const resetAfterSeconds = calculateResetAfterSeconds(resetAt);
  const resetFormatted = resetAt ? formatResetTime(resetAt) : null;
  return {
    usedPercent,
    remainingPercent: usedPercent !== null ? Math.max(0, 100 - usedPercent) : null,
    windowSeconds: windowSeconds ?? null,
    resetAfterSeconds,
    resetAt,
    resetAtFormatted: resetFormatted,
    resetAfterFormatted: resetFormatted,
    ...(valueLabel ? { valueLabel } : {})
  };
};

const buildResult = ({ providerId, providerName, ok, configured, usage, error }) => ({
  providerId,
  providerName,
  ok,
  configured,
  usage: usage ?? null,
  ...(error ? { error } : {}),
  fetchedAt: Date.now()
});

const durationToLabel = (duration, unit) => {
  if (!duration || !unit) return 'limit';
  if (unit === 'TIME_UNIT_MINUTE') return `${duration}m`;
  if (unit === 'TIME_UNIT_HOUR') return `${duration}h`;
  if (unit === 'TIME_UNIT_DAY') return `${duration}d`;
  return 'limit';
};

const durationToSeconds = (duration, unit) => {
  if (!duration || !unit) return null;
  if (unit === 'TIME_UNIT_MINUTE') return duration * 60;
  if (unit === 'TIME_UNIT_HOUR') return duration * 3600;
  if (unit === 'TIME_UNIT_DAY') return duration * 86400;
  return null;
};


export const listConfiguredQuotaProviders = () => {
  const auth = readAuthFile();
  const configured = new Set();

  const anthropicAuth = normalizeAuthEntry(getAuthEntry(auth, ['anthropic', 'claude']));
  if (anthropicAuth?.access || anthropicAuth?.token) {
    configured.add('claude');
  }

  const openaiAuth = normalizeAuthEntry(getAuthEntry(auth, ['openai', 'codex', 'chatgpt']));
  if (openaiAuth?.access || openaiAuth?.token) {
    configured.add('codex');
  }

  if (resolveGeminiCliAuth(auth) || resolveAntigravityAuth()) {
    configured.add('google');
  }

  const zaiAuth = normalizeAuthEntry(getAuthEntry(auth, ['zai-coding-plan', 'zai', 'z.ai']));
  if (zaiAuth?.key || zaiAuth?.token) {
    configured.add('zai-coding-plan');
  }

  const kimiAuth = normalizeAuthEntry(getAuthEntry(auth, ['kimi-for-coding', 'kimi']));
  if (kimiAuth?.key || kimiAuth?.token) {
    configured.add('kimi-for-coding');
  }

  const openrouterAuth = normalizeAuthEntry(getAuthEntry(auth, ['openrouter']));
  if (openrouterAuth?.key || openrouterAuth?.token) {
    configured.add('openrouter');
  }

  const copilotAuth = normalizeAuthEntry(getAuthEntry(auth, ['github-copilot', 'copilot']));
  if (copilotAuth?.access || copilotAuth?.token) {
    configured.add('github-copilot');
    configured.add('github-copilot-addon');
  }

  return Array.from(configured);
};

export const fetchOpenaiQuota = async () => {
  const auth = readAuthFile();
  const entry = normalizeAuthEntry(getAuthEntry(auth, ['openai', 'codex', 'chatgpt']));
  const accessToken = entry?.access ?? entry?.token;

  if (!accessToken) {
    return buildResult({
      providerId: 'openai',
      providerName: 'OpenAI',
      ok: false,
      configured: false,
      error: 'Not configured'
    });
  }

  try {
    const response = await fetch('https://chatgpt.com/backend-api/wham/usage', {
      method: 'GET',
      headers: {
        Authorization: `Bearer ${accessToken}`,
        'Content-Type': 'application/json'
      }
    });

    if (!response.ok) {
      return buildResult({
        providerId: 'openai',
        providerName: 'OpenAI',
        ok: false,
        configured: true,
        error: `API error: ${response.status}`
      });
    }

    const payload = await response.json();
    const primary = payload?.rate_limit?.primary_window ?? null;
    const secondary = payload?.rate_limit?.secondary_window ?? null;

    const windows = {};
    if (primary) {
      windows['5h'] = toUsageWindow({
        usedPercent: primary.used_percent ?? null,
        windowSeconds: primary.limit_window_seconds ?? null,
        resetAt: primary.reset_at ? primary.reset_at * 1000 : null
      });
    }
    if (secondary) {
      windows['weekly'] = toUsageWindow({
        usedPercent: secondary.used_percent ?? null,
        windowSeconds: secondary.limit_window_seconds ?? null,
        resetAt: secondary.reset_at ? secondary.reset_at * 1000 : null
      });
    }

    return buildResult({
      providerId: 'openai',
      providerName: 'OpenAI',
      ok: true,
      configured: true,
      usage: { windows }
    });
  } catch (error) {
    return buildResult({
      providerId: 'openai',
      providerName: 'OpenAI',
      ok: false,
      configured: true,
      error: error instanceof Error ? error.message : 'Request failed'
    });
  }
};

// OAuth Secret value used to init client
// Note: It's ok to save this in git because this is an installed application
// as described here: https://developers.google.com/identity/protocols/oauth2#installed
// "The process results in a client ID and, in some cases, a client secret,
// which you embed in the source code of your application. (In this context,
// the client secret is obviously not treated as a secret.)"
// ref: https://github.com/opgginc/opencode-bar

const ANTIGRAVITY_GOOGLE_CLIENT_ID =
  '1071006060591-tmhssin2h21lcre235vtolojh4g403ep.apps.googleusercontent.com';
const ANTIGRAVITY_GOOGLE_CLIENT_SECRET = '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';
const GEMINI_GOOGLE_CLIENT_ID =
  '681255809395-oo8ft2oprdrnp9e3aqf6av3hmdib135j.apps.googleusercontent.com';
const GEMINI_GOOGLE_CLIENT_SECRET = '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';
const DEFAULT_PROJECT_ID = 'rising-fact-p41fc';
const GOOGLE_FIVE_HOUR_WINDOW_SECONDS = 5 * 60 * 60;
const GOOGLE_DAILY_WINDOW_SECONDS = 24 * 60 * 60;
const GOOGLE_PRIMARY_ENDPOINT = 'https://cloudcode-pa.googleapis.com';

const GOOGLE_ENDPOINTS = [
  'https://daily-cloudcode-pa.sandbox.googleapis.com',
  'https://autopush-cloudcode-pa.sandbox.googleapis.com',
  GOOGLE_PRIMARY_ENDPOINT
];

const GOOGLE_HEADERS = {
  'User-Agent': 'antigravity/1.11.5 windows/amd64',
  'X-Goog-Api-Client': 'google-cloud-sdk vscode_cloudshelleditor/0.1',
  'Client-Metadata':
    '{"ideType":"IDE_UNSPECIFIED","platform":"PLATFORM_UNSPECIFIED","pluginType":"GEMINI"}'
};

const resolveGoogleWindow = (sourceId, resetAt) => {
  if (sourceId === 'gemini') {
    return { label: 'daily', seconds: GOOGLE_DAILY_WINDOW_SECONDS };
  }

  if (sourceId === 'antigravity') {
    const remainingSeconds = typeof resetAt === 'number'
      ? Math.max(0, Math.round((resetAt - Date.now()) / 1000))
      : null;

    if (remainingSeconds !== null && remainingSeconds > 10 * 60 * 60) {
      return { label: 'daily', seconds: GOOGLE_DAILY_WINDOW_SECONDS };
    }

    return { label: '5h', seconds: GOOGLE_FIVE_HOUR_WINDOW_SECONDS };
  }

  return { label: 'daily', seconds: GOOGLE_DAILY_WINDOW_SECONDS };
};

const resolveGeminiCliAuth = (auth) => {
  const entry = normalizeAuthEntry(getAuthEntry(auth, ['google', 'google.oauth']));
  const entryObject = asObject(entry);
  if (!entryObject) {
    return null;
  }

  const oauthObject = asObject(entryObject.oauth) ?? entryObject;
  const accessToken = asNonEmptyString(oauthObject.access) ?? asNonEmptyString(oauthObject.token);
  const refreshParts = parseGoogleRefreshToken(oauthObject.refresh);

  if (!accessToken && !refreshParts.refreshToken) {
    return null;
  }

  return {
    sourceId: 'gemini',
    sourceLabel: 'Gemini',
    accessToken,
    refreshToken: refreshParts.refreshToken,
    projectId: refreshParts.projectId ?? refreshParts.managedProjectId,
    expires: toTimestamp(oauthObject.expires)
  };
};

const resolveAntigravityAuth = () => {
  for (const filePath of ANTIGRAVITY_ACCOUNTS_PATHS) {
    const data = readJsonFile(filePath);
    const accounts = data?.accounts;
    if (Array.isArray(accounts) && accounts.length > 0) {
      const index = typeof data.activeIndex === 'number' ? data.activeIndex : 0;
      const account = accounts[index] ?? accounts[0];
      if (account?.refreshToken) {
        const refreshParts = parseGoogleRefreshToken(account.refreshToken);
        return {
          sourceId: 'antigravity',
          sourceLabel: 'Antigravity',
          refreshToken: refreshParts.refreshToken,
          projectId: asNonEmptyString(account.projectId)
            ?? asNonEmptyString(account.managedProjectId)
            ?? refreshParts.projectId
            ?? refreshParts.managedProjectId,
          email: account.email
        };
      }
    }
  }

  return null;
};

const resolveGoogleAuthSources = () => {
  const auth = readAuthFile();
  const sources = [];

  const geminiAuth = resolveGeminiCliAuth(auth);
  if (geminiAuth) {
    sources.push(geminiAuth);
  }

  const antigravityAuth = resolveAntigravityAuth();
  if (antigravityAuth) {
    sources.push(antigravityAuth);
  }

  return sources;
};

const resolveGoogleOAuthClient = (sourceId) => {
  if (sourceId === 'gemini') {
    return {
      clientId: GEMINI_GOOGLE_CLIENT_ID,
      clientSecret: GEMINI_GOOGLE_CLIENT_SECRET
    };
  }

  return {
    clientId: ANTIGRAVITY_GOOGLE_CLIENT_ID,
    clientSecret: ANTIGRAVITY_GOOGLE_CLIENT_SECRET
  };
};

const refreshGoogleAccessToken = async (refreshToken, clientId, clientSecret) => {
  const response = await fetch('https://oauth2.googleapis.com/token', {
    method: 'POST',
    headers: { 'Content-Type': 'application/x-www-form-urlencoded' },
    body: new URLSearchParams({
      client_id: clientId,
      client_secret: clientSecret,
      refresh_token: refreshToken,
      grant_type: 'refresh_token'
    })
  });

  if (!response.ok) {
    return null;
  }

  const data = await response.json();
  return typeof data?.access_token === 'string' ? data.access_token : null;
};

const fetchGoogleQuotaBuckets = async (accessToken, projectId) => {
  const body = projectId ? { project: projectId } : {};

  try {
    const response = await fetch(`${GOOGLE_PRIMARY_ENDPOINT}/v1internal:retrieveUserQuota`, {
      method: 'POST',
      headers: {
        Authorization: `Bearer ${accessToken}`,
        'Content-Type': 'application/json'
      },
      body: JSON.stringify(body),
      signal: AbortSignal.timeout(15000)
    });

    if (!response.ok) {
      return null;
    }

    return await response.json();
  } catch {
    return null;
  }
};

const fetchGoogleModels = async (accessToken, projectId) => {
  const body = projectId ? { project: projectId } : {};

  for (const endpoint of GOOGLE_ENDPOINTS) {
    try {
      const response = await fetch(`${endpoint}/v1internal:fetchAvailableModels`, {
        method: 'POST',
        headers: {
          Authorization: `Bearer ${accessToken}`,
          'Content-Type': 'application/json',
          ...GOOGLE_HEADERS
        },
        body: JSON.stringify(body),
        signal: AbortSignal.timeout(15000)
      });

      if (response.ok) {
        return await response.json();
      }
    } catch {
      continue;
    }
  }

  return null;
};

export const fetchGoogleQuota = async () => {
  const authSources = resolveGoogleAuthSources();
  if (!authSources.length) {
    return buildResult({
      providerId: 'google',
      providerName: 'Google',
      ok: false,
      configured: false,
      error: 'Not configured'
    });
  }

  const models = {};
  const sourceErrors = [];

  for (const source of authSources) {
    const now = Date.now();
    let accessToken = source.accessToken;

    if (!accessToken || (typeof source.expires === 'number' && source.expires <= now)) {
      if (!source.refreshToken) {
        sourceErrors.push(`${source.sourceLabel}: Missing refresh token`);
        continue;
      }
      const { clientId, clientSecret } = resolveGoogleOAuthClient(source.sourceId);
      accessToken = await refreshGoogleAccessToken(source.refreshToken, clientId, clientSecret);
    }

    if (!accessToken) {
      sourceErrors.push(`${source.sourceLabel}: Failed to refresh OAuth token`);
      continue;
    }

    const projectId = source.projectId ?? DEFAULT_PROJECT_ID;
    let mergedAnyModel = false;

    if (source.sourceId === 'gemini') {
      const quotaPayload = await fetchGoogleQuotaBuckets(accessToken, projectId);
      const buckets = Array.isArray(quotaPayload?.buckets) ? quotaPayload.buckets : [];

      for (const bucket of buckets) {
        const modelId = asNonEmptyString(bucket?.modelId);
        if (!modelId) {
          continue;
        }

        const scopedName = modelId.startsWith(`${source.sourceId}/`)
          ? modelId
          : `${source.sourceId}/${modelId}`;

        const remainingFraction = toNumber(bucket?.remainingFraction);
        const remainingPercent = remainingFraction !== null
          ? Math.round(remainingFraction * 100)
          : null;
        const usedPercent = remainingPercent !== null ? Math.max(0, 100 - remainingPercent) : null;
        const resetAt = toTimestamp(bucket?.resetTime);
        const window = resolveGoogleWindow(source.sourceId, resetAt);

        models[scopedName] = {
          windows: {
            [window.label]: toUsageWindow({
              usedPercent,
              windowSeconds: window.seconds,
              resetAt
            })
          }
        };
        mergedAnyModel = true;
      }
    }

    const payload = await fetchGoogleModels(accessToken, projectId);
    if (payload) {
      for (const [modelName, modelData] of Object.entries(payload.models ?? {})) {
        const scopedName = modelName.startsWith(`${source.sourceId}/`)
          ? modelName
          : `${source.sourceId}/${modelName}`;

        const remainingFraction = modelData?.quotaInfo?.remainingFraction;
        const remainingPercent = typeof remainingFraction === 'number'
          ? Math.round(remainingFraction * 100)
          : null;
        const usedPercent = remainingPercent !== null ? Math.max(0, 100 - remainingPercent) : null;
        const resetAt = modelData?.quotaInfo?.resetTime
          ? new Date(modelData.quotaInfo.resetTime).getTime()
          : null;
        const window = resolveGoogleWindow(source.sourceId, resetAt);
        models[scopedName] = {
          windows: {
            [window.label]: toUsageWindow({
              usedPercent,
              windowSeconds: window.seconds,
              resetAt
            })
          }
        };
        mergedAnyModel = true;
      }
    }

    if (!mergedAnyModel) {
      sourceErrors.push(`${source.sourceLabel}: Failed to fetch models`);
    }
  }

  if (!Object.keys(models).length) {
    return buildResult({
      providerId: 'google',
      providerName: 'Google',
      ok: false,
      configured: true,
      error: sourceErrors[0] ?? 'Failed to fetch models'
    });
  }

  return buildResult({
    providerId: 'google',
    providerName: 'Google',
    ok: true,
    configured: true,
    usage: {
      windows: {},
      models: Object.keys(models).length ? models : undefined
    }
  });
};

const formatMoney = (value) => {
  if (typeof value !== 'number' || !Number.isFinite(value)) return null;
  return value.toFixed(2);
};

export const fetchClaudeQuota = async () => {
  const auth = readAuthFile();
  const entry = normalizeAuthEntry(getAuthEntry(auth, ['anthropic', 'claude']));
  const accessToken = entry?.access ?? entry?.token;

  if (!accessToken) {
    return buildResult({
      providerId: 'claude',
      providerName: 'Claude',
      ok: false,
      configured: false,
      error: 'Not configured'
    });
  }

  try {
    const response = await fetch('https://api.anthropic.com/api/oauth/usage', {
      method: 'GET',
      headers: {
        Authorization: `Bearer ${accessToken}`,
        'anthropic-beta': 'oauth-2025-04-20'
      }
    });

    if (!response.ok) {
      return buildResult({
        providerId: 'claude',
        providerName: 'Claude',
        ok: false,
        configured: true,
        error: `API error: ${response.status}`
      });
    }

    const payload = await response.json();
    const windows = {};
    const fiveHour = payload?.five_hour ?? null;
    const sevenDay = payload?.seven_day ?? null;
    const sevenDaySonnet = payload?.seven_day_sonnet ?? null;
    const sevenDayOpus = payload?.seven_day_opus ?? null;

    if (fiveHour) {
      windows['5h'] = toUsageWindow({
        usedPercent: toNumber(fiveHour.utilization),
        windowSeconds: null,
        resetAt: toTimestamp(fiveHour.resets_at)
      });
    }
    if (sevenDay) {
      windows['7d'] = toUsageWindow({
        usedPercent: toNumber(sevenDay.utilization),
        windowSeconds: null,
        resetAt: toTimestamp(sevenDay.resets_at)
      });
    }
    if (sevenDaySonnet) {
      windows['7d-sonnet'] = toUsageWindow({
        usedPercent: toNumber(sevenDaySonnet.utilization),
        windowSeconds: null,
        resetAt: toTimestamp(sevenDaySonnet.resets_at)
      });
    }
    if (sevenDayOpus) {
      windows['7d-opus'] = toUsageWindow({
        usedPercent: toNumber(sevenDayOpus.utilization),
        windowSeconds: null,
        resetAt: toTimestamp(sevenDayOpus.resets_at)
      });
    }

    return buildResult({
      providerId: 'claude',
      providerName: 'Claude',
      ok: true,
      configured: true,
      usage: { windows }
    });
  } catch (error) {
    return buildResult({
      providerId: 'claude',
      providerName: 'Claude',
      ok: false,
      configured: true,
      error: error instanceof Error ? error.message : 'Request failed'
    });
  }
};

export const fetchCodexQuota = async () => {
  const auth = readAuthFile();
  const entry = normalizeAuthEntry(getAuthEntry(auth, ['openai', 'codex', 'chatgpt']));
  const accessToken = entry?.access ?? entry?.token;
  const accountId = entry?.accountId;

  if (!accessToken) {
    return buildResult({
      providerId: 'codex',
      providerName: 'Codex',
      ok: false,
      configured: false,
      error: 'Not configured'
    });
  }

  try {
    const headers = {
      Authorization: `Bearer ${accessToken}`,
      'Content-Type': 'application/json',
      ...(accountId ? { 'ChatGPT-Account-Id': accountId } : {})
    };
    const response = await fetch('https://chatgpt.com/backend-api/wham/usage', {
      method: 'GET',
      headers
    });

    if (!response.ok) {
      return buildResult({
        providerId: 'codex',
        providerName: 'Codex',
        ok: false,
        configured: true,
        error: `API error: ${response.status}`
      });
    }

    const payload = await response.json();
    const primary = payload?.rate_limit?.primary_window ?? null;
    const secondary = payload?.rate_limit?.secondary_window ?? null;
    const credits = payload?.credits ?? null;

    const windows = {};
    if (primary) {
      windows['5h'] = toUsageWindow({
        usedPercent: toNumber(primary.used_percent),
        windowSeconds: toNumber(primary.limit_window_seconds),
        resetAt: toTimestamp(primary.reset_at)
      });
    }
    if (secondary) {
      windows['weekly'] = toUsageWindow({
        usedPercent: toNumber(secondary.used_percent),
        windowSeconds: toNumber(secondary.limit_window_seconds),
        resetAt: toTimestamp(secondary.reset_at)
      });
    }
    if (credits) {
      const balance = toNumber(credits.balance);
      const unlimited = Boolean(credits.unlimited);
      const label = unlimited
        ? 'Unlimited'
        : balance !== null
          ? `$${formatMoney(balance)} remaining`
          : null;
      windows.credits = toUsageWindow({
        usedPercent: null,
        windowSeconds: null,
        resetAt: null,
        valueLabel: label
      });
    }

    return buildResult({
      providerId: 'codex',
      providerName: 'Codex',
      ok: true,
      configured: true,
      usage: { windows }
    });
  } catch (error) {
    return buildResult({
      providerId: 'codex',
      providerName: 'Codex',
      ok: false,
      configured: true,
      error: error instanceof Error ? error.message : 'Request failed'
    });
  }
};

const buildCopilotWindows = (payload) => {
  const quota = payload?.quota_snapshots ?? {};
  const resetAt = toTimestamp(payload?.quota_reset_date);
  const windows = {};

  const addWindow = (label, snapshot) => {
    if (!snapshot) return;
    const entitlement = toNumber(snapshot.entitlement);
    const remaining = toNumber(snapshot.remaining);
    const usedPercent = entitlement && remaining !== null
      ? Math.max(0, Math.min(100, 100 - (remaining / entitlement) * 100))
      : null;
    const valueLabel = entitlement !== null && remaining !== null
      ? `${remaining.toFixed(0)} / ${entitlement.toFixed(0)} left`
      : null;
    windows[label] = toUsageWindow({
      usedPercent,
      windowSeconds: null,
      resetAt,
      valueLabel
    });
  };

  addWindow('chat', quota.chat);
  addWindow('completions', quota.completions);
  addWindow('premium', quota.premium_interactions);

  return windows;
};

export const fetchCopilotQuota = async () => {
  const auth = readAuthFile();
  const entry = normalizeAuthEntry(getAuthEntry(auth, ['github-copilot', 'copilot']));
  const accessToken = entry?.access ?? entry?.token;

  if (!accessToken) {
    return buildResult({
      providerId: 'github-copilot',
      providerName: 'GitHub Copilot',
      ok: false,
      configured: false,
      error: 'Not configured'
    });
  }

  try {
    const response = await fetch('https://api.github.com/copilot_internal/user', {
      method: 'GET',
      headers: {
        Authorization: `token ${accessToken}`,
        Accept: 'application/json',
        'Editor-Version': 'vscode/1.96.2',
        'X-Github-Api-Version': '2025-04-01'
      }
    });

    if (!response.ok) {
      return buildResult({
        providerId: 'github-copilot',
        providerName: 'GitHub Copilot',
        ok: false,
        configured: true,
        error: `API error: ${response.status}`
      });
    }

    const payload = await response.json();
    return buildResult({
      providerId: 'github-copilot',
      providerName: 'GitHub Copilot',
      ok: true,
      configured: true,
      usage: { windows: buildCopilotWindows(payload) }
    });
  } catch (error) {
    return buildResult({
      providerId: 'github-copilot',
      providerName: 'GitHub Copilot',
      ok: false,
      configured: true,
      error: error instanceof Error ? error.message : 'Request failed'
    });
  }
};

export const fetchCopilotAddonQuota = async () => {
  const auth = readAuthFile();
  const entry = normalizeAuthEntry(getAuthEntry(auth, ['github-copilot', 'copilot']));
  const accessToken = entry?.access ?? entry?.token;

  if (!accessToken) {
    return buildResult({
      providerId: 'github-copilot-addon',
      providerName: 'GitHub Copilot Add-on',
      ok: false,
      configured: false,
      error: 'Not configured'
    });
  }

  try {
    const response = await fetch('https://api.github.com/copilot_internal/user', {
      method: 'GET',
      headers: {
        Authorization: `token ${accessToken}`,
        Accept: 'application/json',
        'Editor-Version': 'vscode/1.96.2',
        'X-Github-Api-Version': '2025-04-01'
      }
    });

    if (!response.ok) {
      return buildResult({
        providerId: 'github-copilot-addon',
        providerName: 'GitHub Copilot Add-on',
        ok: false,
        configured: true,
        error: `API error: ${response.status}`
      });
    }

    const payload = await response.json();
    const windows = buildCopilotWindows(payload);
    const premium = windows.premium ? { premium: windows.premium } : windows;

    return buildResult({
      providerId: 'github-copilot-addon',
      providerName: 'GitHub Copilot Add-on',
      ok: true,
      configured: true,
      usage: { windows: premium }
    });
  } catch (error) {
    return buildResult({
      providerId: 'github-copilot-addon',
      providerName: 'GitHub Copilot Add-on',
      ok: false,
      configured: true,
      error: error instanceof Error ? error.message : 'Request failed'
    });
  }
};

export const fetchKimiQuota = async () => {
  const auth = readAuthFile();
  const entry = normalizeAuthEntry(getAuthEntry(auth, ['kimi-for-coding', 'kimi']));
  const apiKey = entry?.key ?? entry?.token;

  if (!apiKey) {
    return buildResult({
      providerId: 'kimi-for-coding',
      providerName: 'Kimi for Coding',
      ok: false,
      configured: false,
      error: 'Not configured'
    });
  }

  try {
    const response = await fetch('https://api.kimi.com/coding/v1/usages', {
      method: 'GET',
      headers: {
        Authorization: `Bearer ${apiKey}`,
        'Content-Type': 'application/json'
      }
    });

    if (!response.ok) {
      return buildResult({
        providerId: 'kimi-for-coding',
        providerName: 'Kimi for Coding',
        ok: false,
        configured: true,
        error: `API error: ${response.status}`
      });
    }

    const payload = await response.json();
    const windows = {};
    const usage = payload?.usage ?? null;
    if (usage) {
      const limit = toNumber(usage.limit);
      const remaining = toNumber(usage.remaining);
      const usedPercent = limit && remaining !== null
        ? Math.max(0, Math.min(100, 100 - (remaining / limit) * 100))
        : null;
      windows.weekly = toUsageWindow({
        usedPercent,
        windowSeconds: null,
        resetAt: toTimestamp(usage.resetTime)
      });
    }

    const limits = Array.isArray(payload?.limits) ? payload.limits : [];
    for (const limit of limits) {
      const window = limit?.window;
      const detail = limit?.detail;
      const rawLabel = durationToLabel(window?.duration, window?.timeUnit);
      const windowSeconds = durationToSeconds(window?.duration, window?.timeUnit);
      const label = windowSeconds === 5 * 60 * 60 ? `Rate Limit (${rawLabel})` : rawLabel;
      const total = toNumber(detail?.limit);
      const remaining = toNumber(detail?.remaining);
      const usedPercent = total && remaining !== null
        ? Math.max(0, Math.min(100, 100 - (remaining / total) * 100))
        : null;
      windows[label] = toUsageWindow({
        usedPercent,
        windowSeconds,
        resetAt: toTimestamp(detail?.resetTime)
      });
    }

    return buildResult({
      providerId: 'kimi-for-coding',
      providerName: 'Kimi for Coding',
      ok: true,
      configured: true,
      usage: { windows }
    });
  } catch (error) {
    return buildResult({
      providerId: 'kimi-for-coding',
      providerName: 'Kimi for Coding',
      ok: false,
      configured: true,
      error: error instanceof Error ? error.message : 'Request failed'
    });
  }
};

export const fetchOpenRouterQuota = async () => {
  const auth = readAuthFile();
  const entry = normalizeAuthEntry(getAuthEntry(auth, ['openrouter']));
  const apiKey = entry?.key ?? entry?.token;

  if (!apiKey) {
    return buildResult({
      providerId: 'openrouter',
      providerName: 'OpenRouter',
      ok: false,
      configured: false,
      error: 'Not configured'
    });
  }

  try {
    const response = await fetch('https://openrouter.ai/api/v1/credits', {
      method: 'GET',
      headers: {
        Authorization: `Bearer ${apiKey}`,
        'Content-Type': 'application/json'
      }
    });

    if (!response.ok) {
      return buildResult({
        providerId: 'openrouter',
        providerName: 'OpenRouter',
        ok: false,
        configured: true,
        error: `API error: ${response.status}`
      });
    }

    const payload = await response.json();
    const credits = payload?.data ?? {};
    const totalCredits = toNumber(credits.total_credits);
    const totalUsage = toNumber(credits.total_usage);
    const remaining = totalCredits !== null && totalUsage !== null
      ? Math.max(0, totalCredits - totalUsage)
      : null;
    const usedPercent = totalCredits && totalUsage !== null
      ? Math.max(0, Math.min(100, (totalUsage / totalCredits) * 100))
      : null;
    const valueLabel = remaining !== null ? `$${formatMoney(remaining)} remaining` : null;

    const windows = {
      credits: toUsageWindow({
        usedPercent,
        windowSeconds: null,
        resetAt: null,
        valueLabel
      })
    };

    return buildResult({
      providerId: 'openrouter',
      providerName: 'OpenRouter',
      ok: true,
      configured: true,
      usage: { windows }
    });
  } catch (error) {
    return buildResult({
      providerId: 'openrouter',
      providerName: 'OpenRouter',
      ok: false,
      configured: true,
      error: error instanceof Error ? error.message : 'Request failed'
    });
  }
};

const normalizeTimestamp = (value) => {
  if (typeof value !== 'number') return null;
  return value < 1_000_000_000_000 ? value * 1000 : value;
};

const ZAI_TOKEN_WINDOW_SECONDS = { 3: 3600 };

const resolveWindowSeconds = (limit) => {
  if (!limit || !limit.number) return null;
  const unitSeconds = ZAI_TOKEN_WINDOW_SECONDS[limit.unit];
  if (!unitSeconds) return null;
  return unitSeconds * limit.number;
};

const resolveWindowLabel = (windowSeconds) => {
  if (!windowSeconds) return 'tokens';
  if (windowSeconds % 86400 === 0) {
    const days = windowSeconds / 86400;
    return days === 7 ? 'weekly' : `${days}d`;
  }
  if (windowSeconds % 3600 === 0) {
    return `${windowSeconds / 3600}h`;
  }
  return `${windowSeconds}s`;
};

export const fetchZaiQuota = async () => {
  const auth = readAuthFile();
  const entry = normalizeAuthEntry(getAuthEntry(auth, ['zai-coding-plan', 'zai', 'z.ai']));
  const apiKey = entry?.key ?? entry?.token;

  if (!apiKey) {
    return buildResult({
      providerId: 'zai-coding-plan',
      providerName: 'z.ai',
      ok: false,
      configured: false,
      error: 'Not configured'
    });
  }

  try {
    const response = await fetch('https://api.z.ai/api/monitor/usage/quota/limit', {
      method: 'GET',
      headers: {
        Authorization: `Bearer ${apiKey}`,
        'Content-Type': 'application/json'
      }
    });

    if (!response.ok) {
      return buildResult({
        providerId: 'zai-coding-plan',
        providerName: 'z.ai',
        ok: false,
        configured: true,
        error: `API error: ${response.status}`
      });
    }

    const payload = await response.json();
    const limits = Array.isArray(payload?.data?.limits) ? payload.data.limits : [];
    const tokensLimit = limits.find((limit) => limit?.type === 'TOKENS_LIMIT');
    const windowSeconds = resolveWindowSeconds(tokensLimit);
    const windowLabel = resolveWindowLabel(windowSeconds);
    const resetAt = tokensLimit?.nextResetTime ? normalizeTimestamp(tokensLimit.nextResetTime) : null;
    const usedPercent = typeof tokensLimit?.percentage === 'number' ? tokensLimit.percentage : null;

    const windows = {};
    if (tokensLimit) {
      windows[windowLabel] = toUsageWindow({
        usedPercent,
        windowSeconds,
        resetAt
      });
    }

    return buildResult({
      providerId: 'zai-coding-plan',
      providerName: 'z.ai',
      ok: true,
      configured: true,
      usage: { windows }
    });
  } catch (error) {
    return buildResult({
      providerId: 'zai-coding-plan',
      providerName: 'z.ai',
      ok: false,
      configured: true,
      error: error instanceof Error ? error.message : 'Request failed'
    });
  }
};

export const fetchQuotaForProvider = async (providerId) => {
  switch (providerId) {
    case 'claude':
      return fetchClaudeQuota();
    case 'codex':
      return fetchCodexQuota();
    case 'github-copilot':
      return fetchCopilotQuota();
    case 'github-copilot-addon':
      return fetchCopilotAddonQuota();
    case 'google':
      return fetchGoogleQuota();
    case 'kimi-for-coding':
      return fetchKimiQuota();
    case 'openrouter':
      return fetchOpenRouterQuota();
    case 'zai-coding-plan':
      return fetchZaiQuota();
    default:
      return buildResult({
        providerId,
        providerName: providerId,
        ok: false,
        configured: false,
        error: 'Unsupported provider'
      });
  }
};