/**
 * AKSRT frontend request adapter.
 *
 * Owns the injected REST root, nonce headers, response envelopes, and
 * abort-aware error normalization used by modal loaders.
 *
 * @package AKSRT
 */
(function (window) {
  "use strict";

  function data() {
    return window.aksrtData || window.aksrt || {};
  }

  function restBase() {
    var config = data();
    var raw = config.restUrl || config.apiUrl || config.rest_url || "";
    var siteUrl = config.siteUrl || config.homeUrl || (window.location.origin + "/");

    if (window.location.protocol === "https:" && siteUrl.substring(0, 5) === "http:") {
      siteUrl = "https:" + siteUrl.substring(5);
    }

    if (raw) return String(raw).replace(/\/$/, "");
    return String(siteUrl).replace(/\/$/, "") + "/index.php?rest_route=/aksrt/v1";
  }

  function appendQuery(url, query) {
    if (!query) return url;
    var parts = [];

    if (typeof query === "string") {
      parts = query.replace(/^\?/, "").split("&").filter(Boolean);
    } else if (typeof query === "object") {
      Object.keys(query).forEach(function (key) {
        if (query[key] === undefined || query[key] === null) return;
        parts.push(encodeURIComponent(key) + "=" + encodeURIComponent(String(query[key])));
      });
    }

    if (!parts.length) return url;
    return url + (url.indexOf("?") >= 0 ? "&" : "?") + parts.join("&");
  }

  function url(path, query) {
    path = String(path || "");
    var inlineQuery = "";
    var queryIndex = path.indexOf("?");

    if (queryIndex >= 0) {
      inlineQuery = path.slice(queryIndex + 1);
      path = path.slice(0, queryIndex);
    }

    if (/^https?:\/\//i.test(path)) {
      return appendQuery(path, query || inlineQuery);
    }

    if (path.charAt(0) !== "/") path = "/" + path;
    var base = restBase();
    var result = base.indexOf("rest_route=") >= 0 ? base + path : base + path;
    return appendQuery(result, query || inlineQuery);
  }

  function headers(options) {
    var config = data();
    var source = (options && options.headers) || {};
    var result = {};
    var nonce = config.restNonce || config.nonce || "";

    Object.keys(source).forEach(function (key) {
      result[key] = source[key];
    });

    if (!result.Accept) result.Accept = "application/json, text/html;q=0.9, */*;q=0.8";
    if (nonce && !result["X-WP-Nonce"]) result["X-WP-Nonce"] = nonce;

    if (options && options.body !== undefined && options.body !== null &&
        !(window.FormData && options.body instanceof window.FormData) &&
        !result["Content-Type"]) {
      result["Content-Type"] = "application/json";
    }

    return result;
  }

  function responseError(result) {
    var json = result.json;
    var message = json && (json.message || (json.data && json.data.message));
    var error = new Error(message || (result.status ? "请求失败（HTTP " + result.status + "）" : "请求失败"));
    error.status = result.status;
    error.code = result.status === 401 ? "unauthorized" : "http_error";
    error.response = result;
    error.json = json;
    return error;
  }

  function parseResponse(response) {
    return response.text().then(function (text) {
      var type = (response.headers.get("content-type") || "").toLowerCase();
      var json = null;
      var trimmed = String(text || "").trim();

      if (type.indexOf("application/json") >= 0 || trimmed.charAt(0) === "{" || trimmed.charAt(0) === "[") {
        try {
          json = trimmed ? JSON.parse(trimmed) : {};
        } catch (error) {
          json = null;
        }
      }

      return {
        ok: response.ok,
        status: response.status,
        headers: response.headers,
        text: text,
        json: json,
        data: json && json.data !== undefined ? json.data : json,
      };
    });
  }

  function request(path, options) {
    options = Object.assign({}, options || {});
    var requestUrl = url(path, options.query);
    delete options.query;

    var fetchOptions = Object.assign({}, options, {
      credentials: options.credentials || "same-origin",
      headers: headers(options),
    });

    return window.fetch(requestUrl, fetchOptions).then(function (response) {
      return parseResponse(response);
    }).then(function (result) {
      if (!result.ok || (result.json && result.json.success === false)) {
        throw responseError(result);
      }
      return result;
    });
  }

  window.AksrtRequest = {
    url: url,
    request: request,
    get: function (path, options) {
      return request(path, Object.assign({}, options || {}, { method: "GET" }));
    },
    post: function (path, body, options) {
      return request(path, Object.assign({}, options || {}, {
        method: "POST",
        body: body,
      }));
    },
  };
})(window);