/* global window, document */

(function () {
  'use strict';

  function getSectok() {
    try {
      if (window.JSINFO && window.JSINFO.sectok) return String(window.JSINFO.sectok);
    } catch (e) {}

    try {
      var inp = document.querySelector('input[name="sectok"], input[name="securitytoken"]');
      if (inp && inp.value) return String(inp.value);
    } catch (e2) {}

    return '';
  }

  function getPageId() {
    try {
      if (window.JSINFO && window.JSINFO.id) return String(window.JSINFO.id);
    } catch (e) {}

    try {
      var input = document.querySelector('input[name="id"]');
      if (input && input.value) return String(input.value);
    } catch (e2) {}

    return '';
  }

  function getBaseUrl() {
    try {
      if (window.DOKU_BASE) return String(window.DOKU_BASE);
    } catch (e) {}

    try {
      if (window.JSINFO && window.JSINFO.base) return String(window.JSINFO.base);
    } catch (e2) {}

    return '/';
  }

  function requestPageLink(cmd, params) {
    var pageId = getPageId();
    if (!pageId) return Promise.reject(new Error('missing page id'));

    var endpoint = getBaseUrl() + 'lib/plugins/luxtools/pagelink.php';

    var payload = new window.URLSearchParams();
    payload.set('cmd', cmd);
    payload.set('id', pageId);
    if (params && typeof params === 'object') {
      Object.keys(params).forEach(function (key) {
        payload.set(key, String(params[key]));
      });
    }

    return window.fetch(endpoint, {
      method: 'POST',
      credentials: 'same-origin',
      headers: { 'Content-Type': 'application/x-www-form-urlencoded; charset=UTF-8' },
      body: payload.toString()
    }).then(function (res) {
      return res.json().catch(function () { return null; }).then(function (body) {
        if (!res.ok || !body || body.ok !== true) {
          throw new Error('request failed');
        }
        return body;
      });
    });
  }

  function ensurePageLink() {
    return requestPageLink('ensure', { sectok: getSectok() });
  }

  function unlinkPageLink() {
    return requestPageLink('unlink', { sectok: getSectok() });
  }

  function triggerDownload(pageId) {
    try {
      var endpoint = getBaseUrl() + 'lib/plugins/luxtools/pagelink.php';
      var href = endpoint + '?cmd=download&id=' + encodeURIComponent(pageId);

      var a = document.createElement('a');
      a.href = href;
      a.download = '.pagelink';
      a.style.display = 'none';
      document.body.appendChild(a);
      a.click();
      document.body.removeChild(a);
    } catch (e) {
      // ignore
    }
  }

  function fetchPageLinkInfo(pageId) {
    if (!pageId) return Promise.reject(new Error('missing page id'));

    var endpoint = getBaseUrl() + 'lib/plugins/luxtools/pagelink.php';
    var query = endpoint + '?cmd=info&id=' + encodeURIComponent(pageId);

    return window.fetch(query, {
      method: 'GET',
      credentials: 'same-origin'
    }).then(function (res) {
      return res.json().catch(function () { return null; }).then(function (body) {
        if (!res.ok || !body || body.ok !== true) {
          throw new Error('request failed');
        }
        return body;
      });
    });
  }

  function attachDocInfoLink() {
    var container = document.querySelector('.docInfo');
    if (!container || !container.getAttribute) return;
    if (container.getAttribute('data-luxtools-pagelink-docinfo') === '1') return;
    container.setAttribute('data-luxtools-pagelink-docinfo', '1');

    var pageId = getPageId();
    if (!pageId) return;

    fetchPageLinkInfo(pageId).then(function (info) {
      var link = document.createElement('a');
      link.href = '#';

      if (!info || !info.uuid) {
        link.textContent = 'Link Page';
        link.addEventListener('click', function (e) {
          e.preventDefault();
          ensurePageLink().then(function (res) {
            if (!res || !res.uuid) throw new Error('no uuid');
            triggerDownload(pageId);
          }).catch(function (err) {
            if (window.console && window.console.warn) {
              window.console.warn('PageLink ensure failed:', err);
            }
          });
        });
      } else if (info.linked) {
        link.textContent = 'Unlink Page';
        link.addEventListener('click', function (e) {
          e.preventDefault();
          if (!window.confirm('Unlink page?')) return;
          unlinkPageLink().then(function () {
            window.setTimeout(function () {
              try { window.location.reload(); } catch (e2) {}
            }, 400);
          }).catch(function (err) {
            if (window.console && window.console.warn) {
              window.console.warn('PageLink unlink failed:', err);
            }
          });
        });
      } else {
        link.textContent = 'Download Link File';
        link.addEventListener('click', function (e) {
          e.preventDefault();
          triggerDownload(pageId);
        });
      }

      var first = container.firstChild;
      container.insertBefore(link, first);
      if (first) {
        container.insertBefore(document.createTextNode(' · '), first);
      }
    }).catch(function () {
      // ignore failures
    });
  }

  document.addEventListener('DOMContentLoaded', function () {
    attachDocInfoLink();
  }, false);
})();