/**
 * Vazin Pay → Google Sheets rate logger
 * Source: https://pay.vazin.online/v3/portal/rates
 *
 * Setup:
 * 1) Open your Google Sheet → Extensions → Apps Script
 * 2) Paste this whole file, Save
 * 3) Run setupVazinRates once (authorize when asked)
 * 4) Optional: Triggers → verify hourly trigger exists
 */
var VAZIN_RATES_URL = 'https://pay.vazin.online/v3/portal/rates';
var SHEET_WALLET = 'wallet_rates';
var SHEET_TOMAN = 'toman_ref';
var SHEET_META = 'meta';

function setupVazinRates() {
  var ss = SpreadsheetApp.getActive();
  ensureSheet_(ss, SHEET_WALLET, [
    'logged_at_utc', 'asset', 'units_per_usd', 'deposit_units_per_usd',
    'withdrawal_units_per_usd', 'deposit_enabled', 'withdrawal_enabled',
    'stale', 'exchange_available', 'rate_updated_at'
  ]);
  ensureSheet_(ss, SHEET_TOMAN, [
    'logged_at_utc', 'asset', 'toman', 'source', 'age_seconds', 'ref_updated_at'
  ]);
  ensureSheet_(ss, SHEET_META, ['key', 'value']);
  upsertMeta_('source_url', VAZIN_RATES_URL);
  upsertMeta_('setup_at_utc', new Date().toISOString());
  // remove old triggers for this function, then create hourly
  ScriptApp.getProjectTriggers().forEach(function (t) {
    if (t.getHandlerFunction() === 'logVazinRates') ScriptApp.deleteTrigger(t);
  });
  ScriptApp.newTrigger('logVazinRates').timeBased().everyHours(1).create();
  // also run once now
  logVazinRates();
  SpreadsheetApp.getUi().alert('Vazin rates: setup OK. Hourly logging is on.');
}

function logVazinRates() {
  var ss = SpreadsheetApp.getActive();
  var res = UrlFetchApp.fetch(VAZIN_RATES_URL, {
    muteHttpExceptions: true,
    followRedirects: true,
    validateHttpsCertificates: true
  });
  var code = res.getResponseCode();
  var body = res.getContentText();
  if (code !== 200) {
    upsertMeta_('last_error', code + ' ' + body.slice(0, 200));
    throw new Error('Rates fetch failed: HTTP ' + code);
  }
  var data = JSON.parse(body);
  var now = new Date().toISOString();
  var wallet = ss.getSheetByName(SHEET_WALLET);
  var toman = ss.getSheetByName(SHEET_TOMAN);
  if (!wallet || !toman) {
    throw new Error('Run setupVazinRates first');
  }

  var walletRows = (data.rates || []).map(function (r) {
    return [
      now,
      String(r.asset || '').toUpperCase(),
      num_(r.units_per_usd),
      num_(r.deposit_units_per_usd),
      num_(r.withdrawal_units_per_usd),
      !!r.deposit_enabled,
      !!r.withdrawal_enabled,
      !!r.stale,
      !!r.exchange_available,
      r.updated_at || ''
    ];
  });
  if (walletRows.length) {
    wallet.getRange(wallet.getLastRow() + 1, 1, walletRows.length, walletRows[0].length).setValues(walletRows);
  }

  var tomanRows = (data.reference || []).map(function (r) {
    return [
      now,
      String(r.asset || '').toUpperCase(),
      num_(r.toman),
      r.source || '',
      r.age_seconds == null ? '' : Number(r.age_seconds),
      r.updated_at || ''
    ];
  });
  if (tomanRows.length) {
    toman.getRange(toman.getLastRow() + 1, 1, tomanRows.length, tomanRows[0].length).setValues(tomanRows);
  }

  upsertMeta_('last_ok_utc', now);
  upsertMeta_('last_wallet_rows', String(walletRows.length));
  upsertMeta_('last_toman_rows', String(tomanRows.length));
  upsertMeta_('last_error', '');
}

function ensureSheet_(ss, name, headers) {
  var sh = ss.getSheetByName(name);
  if (!sh) sh = ss.insertSheet(name);
  if (sh.getLastRow() === 0) {
    sh.getRange(1, 1, 1, headers.length).setValues([headers]);
    sh.setFrozenRows(1);
  }
  return sh;
}

function upsertMeta_(key, value) {
  var ss = SpreadsheetApp.getActive();
  var sh = ensureSheet_(ss, SHEET_META, ['key', 'value']);
  var values = sh.getDataRange().getValues();
  for (var i = 1; i < values.length; i++) {
    if (String(values[i][0]) === key) {
      sh.getRange(i + 1, 2).setValue(value);
      return;
    }
  }
  sh.appendRow([key, value]);
}

function num_(v) {
  var n = Number(v);
  return isFinite(n) ? n : '';
}