// Emblem Scanner Library - Utility functions for QR scanning
// Self-contained utility functions for camera rules, device detection, and query building

var camera_rules = null;

/**
 * Get system information
 */
function get_system_info() {
  return wx.getSystemInfoSync();
}

/**
 * Get phone model from system info
 */
function get_phone_model() {
  var ret = get_system_info().model;
  console.log("phone model", ret);
  return ret;
}

/**
 * Match camera rules based on phone model
 */
function match_camera_rules(model, rules, default_zoom) {
  console.log(model, "apply zoom rules:", rules);
  var best_match = null;
  for (var rule of rules) {
    if (model.toLowerCase().startsWith(rule.model.toLowerCase())) {
      if (!best_match || rule.model.length > best_match.model.length) {
        best_match = rule;
      }
    }
  }
  if (best_match) {
    console.log("found best match", best_match);
    return best_match;
  }
  var ret = {
    zoom: default_zoom,
    web_view: false
  };
  console.log("using default", ret);
  return ret;
}

/**
 * Get camera rule from API or cache
 */
function get_camera_rule(max_zoom, cb) {
  var default_zoom = 4;
  if (max_zoom && max_zoom >= 60) {
    /*
     * 2024.06.01: in some Huawei/Honor models, the scale is different, use 40
     * in this case so we don't need to set up rules for each specific model
     */
    console.log(`max zoom is ${max_zoom}, default zoom will be 40`);
    default_zoom = 40;
  }
  if (camera_rules) {
    let rule = match_camera_rules(get_phone_model(), camera_rules, default_zoom);
    cb(rule);
  } else {
    var url = 'https://themblem.com/api/v1/camera-rules/';
    wx.request({
      url,
      complete: (res) => {
        var rules = res.data;
        camera_rules = rules;
        let rule = match_camera_rules(get_phone_model(), rules, default_zoom);
        cb(rule);
      }
    });
  }
}

/**
 * Build query string for web-view camera
 */
function make_query(zoom, return_page, real_ip, tenant_id) {
  var ret = "zoom=" + zoom;
  var ui = wx.getStorageSync('userinfo') || {};
  ret += "&phonemodel=" + encodeURIComponent(get_phone_model());
  ret += "&realip=" + (real_ip || "");
  ret += "&emblem_id=" + (ui.emblem_id || "");
  ret += "&nick_name=" + encodeURIComponent(ui.nickName || "");
  ret += "&tenant=" + (tenant_id || "");
  ret += "&tk=" + Date.now();
  if (return_page) {
    ret += "&wx_redirect_to=" + encodeURIComponent(return_page);
  }
  console.log("Web-view query:", ret);
  return ret;
}

/**
 * Fetch real IP address
 */
function fetch_real_ip(callback) {
  wx.request({
    url: 'https://whatsmyip.hondcloud.com',
    success: (res) => {
      const ip = res.data || '';
      console.log('Real IP fetched:', ip);
      callback(null, ip);
    },
    fail: (err) => {
      console.error('Failed to fetch real IP:', err);
      callback(err, '');
    }
  });
}

/**
 * Get tenant ID from storage
 */
function get_tenant_id() {
  const tenant_id = wx.getStorageSync('tenant_id') || '';
  console.log('Tenant ID:', tenant_id);
  return tenant_id;
}

/**
 * Check if QR code matches Emblem pattern
 */
function is_emblem_qr_pattern(p) {
  if (p.search(/code=[0-9a-zA-Z]+/) >= 0) return true;
  if (p.search(/id=[0-9a-zA-Z]+/) >= 0) return true;
  if (p.search(/c=[0-9a-zA-Z]+/) >= 0) return true;
  if (p.search(/https:\/\/xy.ltd\/v\/[0-9a-zA-Z]+/) >= 0) return true;
  return false;
}

module.exports = {
  get_system_info,
  get_phone_model,
  get_camera_rule,
  make_query,
  fetch_real_ip,
  get_tenant_id,
  is_emblem_qr_pattern
};