/**
 * AKSRT Captcha front-end runtime — cloud providers only.
 *
 * Mounts are registered internally by uid and resolved by scene plus DOM scope.
 * The only public surface is window.AKSRTCaptcha.
 */
(function () {
  'use strict';

  var TOKEN_FIELDS = Object.freeze([
    'captcha_verified',
    'aksrt_captcha_challenge',
    'aksrt_captcha_proof',
    'cf_turnstile_response',
    'tencent_ticket', 'tencent_randstr',
    'geetest_lot_number', 'geetest_captcha_output', 'geetest_pass_token', 'geetest_gen_time',
    'aliyun_captcha_verify_param'
  ]);
  var loaders = {};
  var instances = {};
  var scenes = {};

  function asElement(scope) {
    if (!scope) return null;
    if (scope.nodeType === 1 || scope.nodeType === 9) return scope;
    if (typeof scope !== 'string') return null;
    if (instances[scope]) return instances[scope].box;
    try { return document.querySelector(scope); } catch (_) { return null; }
  }

  function scopeBoundary(box, config) {
    if (config.scope) {
      try {
        var configured = document.querySelector(config.scope);
        if (configured) return configured;
      } catch (_) {}
    }
    return box.closest('[data-aksrt-captcha-scope], form, [data-aksrt-download-box], [data-aksrt-auth], .aksrt-modal, [data-signin-captcha], #comments') || box.parentElement;
  }

  function register(instance) {
    instances[instance.uid] = instance;
    scenes[instance.scene] = scenes[instance.scene] || [];
    if (scenes[instance.scene].indexOf(instance) === -1) scenes[instance.scene].push(instance);
  }

  function resolve(scene, scope) {
    scan();
    if (typeof scope === 'string' && instances[scope] && instances[scope].scene === scene) {
      return instances[scope];
    }
    var candidates = scenes[scene] || [];
    var element = asElement(scope);
    if (element && element.getAttribute) {
      var uid = element.getAttribute('data-aksrt-captcha-uid') || element.getAttribute('data-captcha-uid');
      if (uid && instances[uid] && instances[uid].scene === scene) return instances[uid];
    }
    if (!element) return scope ? null : (candidates.length === 1 ? candidates[0] : null);
    var matches = candidates.filter(function (instance) {
      var boundary = instance.scope;
      return element === instance.box || element === instance.mount || element === boundary ||
        instance.box.contains(element) || instance.mount.contains(element) ||
        (boundary && boundary.contains(element)) ||
        (element.contains && (element.contains(instance.box) || (boundary && element.contains(boundary))));
    });
    if (matches.length === 1) return matches[0];
    if (!matches.length) return null;
    matches.sort(function (a, b) {
      if (a.scope === b.scope) return 0;
      if (a.scope && b.scope && a.scope.contains(b.scope)) return 1;
      if (a.scope && b.scope && b.scope.contains(a.scope)) return -1;
      return 0;
    });
    return matches[0];
  }

  function verify(scene, scope) {
    var instance = resolve(scene, scope);
    if (!instance) return Promise.resolve(true);
    return instance.verify();
  }

  function collect(scene, scope) {
    var instance = resolve(scene, scope);
    return instance ? instance.collect() : {};
  }

  function reset(scene, scope) {
    var instance = resolve(scene, scope);
    if (instance) instance.reset();
  }

  function releaseRunLock(instance) {
    instance.runLocked = false;
    var waiters = instance.lockWaiters.slice();
    instance.lockWaiters = [];
    waiters.forEach(function (resolveWaiter) { resolveWaiter(null); });
  }

  function run(scene, scope) {
    var instance = resolve(scene, scope);
    if (!instance) return Promise.resolve({});
    if (instance.runLocked) {
      return new Promise(function (resolveWaiter) { instance.lockWaiters.push(resolveWaiter); });
    }
    instance.runLocked = true;
    return instance.verify().then(function (passed) {
      if (!passed) releaseRunLock(instance);
      return passed ? instance.collect() : null;
    }).catch(function (error) {
      releaseRunLock(instance);
      throw error;
    });
  }

  window.AKSRTCaptcha = Object.freeze({
    verify: verify,
    collect: collect,
    reset: reset,
    run: run,
    TOKEN_FIELDS: TOKEN_FIELDS
  });

  function scan(root, reason) {
    var scope = root && root.querySelectorAll ? root : document;
    var mounts = [];
    if (scope.nodeType === 1 && scope.matches('[data-aksrt-captcha-config]')) mounts.push(scope);
    Array.prototype.push.apply(mounts, scope.querySelectorAll('[data-aksrt-captcha-config]'));
    Array.prototype.forEach.call(mounts, function (mount) {
      if (mount.dataset.aksrtCaptchaBound) return;
      var config;
      try {
        config = JSON.parse(mount.getAttribute('data-aksrt-captcha-config'));
      } catch (_) {
        return;
      }
      if (!config || !config.scene || !config.uid || !config.vid) return;
      mount.dataset.aksrtCaptchaBound = '1';
      initMount(config, mount);
    });
  }

  function initMount(C, mount) {
    var box = document.getElementById(C.uid);
    var hField = document.getElementById(C.vid);
    if (!box || !hField) return;

    var container = box.closest('form') || mount;
    mount.setAttribute('data-aksrt-captcha-uid', C.uid);
    var verified = false;
    var pending = [];
    var refreshingChallenge = null;
    var providerReset = function () {};
    var triggerCaptcha = function () {
      showTip('验证码加载中，请稍候', '#e67e22');
      finishPending(false);
    };

    function loadScriptOnce(key, src, readyCheck) {
      if (typeof readyCheck === 'function' && readyCheck()) return Promise.resolve();
      if (loaders[key]) return loaders[key];
      loaders[key] = new Promise(function (resolveLoad, rejectLoad) {
        var existing = document.querySelector('script[data-aksrt-sdk="' + key + '"]');
        if (existing) {
          if (typeof readyCheck === 'function' && readyCheck()) { resolveLoad(); return; }
          existing.addEventListener('load', resolveLoad, { once: true });
          existing.addEventListener('error', function () { rejectLoad(new Error(key + ' load failed')); }, { once: true });
          return;
        }
        var script = document.createElement('script');
        script.src = src;
        script.async = true;
        script.setAttribute('data-aksrt-sdk', key);
        script.onload = resolveLoad;
        script.onerror = function () { rejectLoad(new Error(key + ' load failed')); };
        document.head.appendChild(script);
      });
      return loaders[key];
    }

    function setField(name, value) {
      var field = container.querySelector('input[name="' + name + '"]');
      if (!field) {
        field = document.createElement('input');
        field.type = 'hidden';
        field.name = name;
        container.appendChild(field);
      }
      field.value = value == null ? '' : value;
    }

    function collectFields() {
      var payload = {};
      TOKEN_FIELDS.forEach(function (name) {
        var field = container.querySelector('input[name="' + name + '"]');
        if (field && field.value !== '') payload[name] = field.value;
      });
      return payload;
    }

    function refreshChallenge() {
      if (!C.challenge_url || typeof window.fetch !== 'function') return Promise.resolve();
      if (refreshingChallenge) return refreshingChallenge;
      refreshingChallenge = window.fetch(C.challenge_url, {
        method: 'POST',
        credentials: 'same-origin',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ scene: C.scene })
      }).then(function (response) {
        return response.json().catch(function () { return {}; }).then(function (body) {
          if (!response.ok || !body || body.success === false) throw new Error(body.message || 'challenge refresh failed');
          var data = body.data || body;
          if (!data.challenge) throw new Error('challenge missing');
          setField('aksrt_captcha_challenge', data.challenge);
        });
      }).catch(function () {
        showTip('无法刷新人机验证会话，请刷新页面重试', '#e74c3c');
      }).finally(function () {
        refreshingChallenge = null;
      });
      return refreshingChallenge;
    }

    function clearProviderTokens() {
      TOKEN_FIELDS.forEach(function (name) {
        if (name === 'captcha_verified' || name === 'aksrt_captcha_challenge' || name === 'aksrt_captcha_proof') return;
        Array.prototype.forEach.call(container.querySelectorAll('input[name="' + name + '"]'), function (field) {
          field.remove();
        });
      });
    }

    function resetVerificationState() {
      verified = false;
      releaseRunLock(instance);
      hField.value = '0';
      setField('aksrt_captcha_proof', '');
      clearProviderTokens();
      try { providerReset(); } catch (_) {}
      refreshChallenge();
    }

    function finishPending(ok) {
      var callbacks = pending.slice();
      pending = [];
      callbacks.forEach(function (callback) { callback(!!ok); });
    }

    function cancelPending(message) {
      if (message) showTip(message, '#e67e22');
      finishPending(false);
    }

    function providerPayload() {
      var payload = collectFields();
      payload.scene = C.scene;
      return payload;
    }

    function exchangeVerification() {
      if (!C.exchange_url || typeof window.fetch !== 'function') {
        cancelPending('人机验证服务不可用，请刷新页面重试');
        return;
      }
      window.fetch(C.exchange_url, {
        method: 'POST',
        credentials: 'same-origin',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify(providerPayload())
      }).then(function (response) {
        return response.json().catch(function () { return {}; }).then(function (body) {
          if (!response.ok || !body || body.success === false) throw new Error(body.message || '人机验证失败');
          var data = body.data || body;
          if (!data.proof) throw new Error('人机验证凭证缺失');
          setField('aksrt_captcha_proof', data.proof);
          clearProviderTokens();
          completeVerification();
        });
      }).catch(function (error) {
        cancelPending(error.message || '人机验证失败，请重试');
        resetVerificationState();
      });
    }

    function completeProviderVerification() {
      hField.value = '1';
      exchangeVerification();
    }

    function completeVerification() {
      verified = true;
      hField.value = '1';
      finishPending(true);
    }

    function showTip(message, color) {
      var tip = box.querySelector('.captcha-tip');
      if (!tip) {
        tip = document.createElement('div');
        tip.className = 'captcha-tip';
        tip.style.cssText = 'font-size:12px;margin-top:4px;text-align:left;';
        box.appendChild(tip);
      }
      tip.style.color = color || '#e74c3c';
      tip.textContent = message;
      setTimeout(function () { if (tip.parentNode) tip.remove(); }, 4000);
    }

    function showLoading() {
      box.innerHTML = '<div style="text-align:center;padding:20px;color:#9ca3af;">验证码加载中...</div>';
    }

    function clearLoading() {
      box.innerHTML = '';
    }

    var instance = {
      uid: C.uid,
      scene: C.scene,
      box: box,
      mount: mount,
      scope: scopeBoundary(box, C),
      runLocked: false,
      lockWaiters: [],
      collect: collectFields,
      reset: resetVerificationState,
      verify: function () {
        var challengeField = container.querySelector('input[name="aksrt_captcha_challenge"]');
        var preparation = challengeField && challengeField.value ? Promise.resolve() : refreshChallenge();
        return preparation.then(function () {
          challengeField = container.querySelector('input[name="aksrt_captcha_challenge"]');
          if (!challengeField || !challengeField.value) {
            showTip('人机验证会话未就绪，请稍后重试', '#e74c3c');
            return false;
          }
          if (verified || hField.value === '1') return true;
          return new Promise(function (resolveVerify) {
            pending.push(resolveVerify);
            if (pending.length === 1) triggerCaptcha();
          });
        });
      }
    };
    register(instance);
    refreshingChallenge = refreshChallenge();

    function loadTencent() {
      showLoading();
      loadScriptOnce('tencent', 'https://turing.captcha.qcloud.com/TJCaptcha.js', function () {
        return typeof window.TencentCaptcha !== 'undefined';
      }).then(function () {
        clearLoading();
        var captchaInstance = null;
        triggerCaptcha = function () {
          if (!captchaInstance) {
            captchaInstance = new window.TencentCaptcha(C.tc.app_id, function (result) {
              if (result.ret === 2) { cancelPending('已取消验证'); return; }
              if (result.ret === 0 && result.ticket) {
                if (result.ticket.indexOf('trerror_') === 0) {
                  cancelPending('验证码服务异常，请刷新页面重试');
                  return;
                }
                setField('tencent_ticket', result.ticket);
                setField('tencent_randstr', result.randstr);
                completeProviderVerification();
                return;
              }
              var errorMap = { 1001: '验证码组件加载失败', 1002: '验证码超时', 1006: '验证码配置拉取失败', 1008: '验证码页面加载异常', 1012: '验证码刷新次数过多', 1013: '验证码网络异常' };
              cancelPending(errorMap[result.errorCode] || '验证码异常，请重试');
            }, { userLanguage: 'zh-cn' });
          }
          captchaInstance.show();
        };
      }).catch(function () {
        clearLoading();
        cancelPending('验证码组件加载失败，请刷新重试');
      });
    }

    function loadCloudflare() {
      var widgetId = null;
      var verifying = false;
      var modal = null;

      function closeModal() {
        if (widgetId !== null && typeof window.turnstile !== 'undefined') {
          try { window.turnstile.remove(widgetId); } catch (_) {}
        }
        widgetId = null;
        if (modal && modal.parentNode) modal.parentNode.removeChild(modal);
        modal = null;
      }

      function renderWidget() {
        if (typeof window.turnstile === 'undefined') { setTimeout(renderWidget, 200); return; }
        widgetId = window.turnstile.render('#modalWidget_' + C.uid, {
          sitekey: C.cf.site_key,
          theme: C.cf.theme,
          size: C.cf.size,
          action: 'aksrt-verify',
          cdata: C.scene,
          callback: function (token) {
            if (!verifying) return;
            verifying = false;
            setField('cf_turnstile_response', token);
            closeModal();
            completeProviderVerification();
          },
          'error-callback': function () {
            verifying = false;
            closeModal();
            cancelPending('验证码失败，请重试');
          },
          'expired-callback': function () {
            verifying = false;
            closeModal();
            cancelPending('验证码已过期，请重新验证');
          }
        });
      }

      function createModal() {
        modal = document.createElement('div');
        modal.className = 'aksrt-captcha-modal-overlay';
        modal.innerHTML = '<div class="aksrt-captcha-modal-backdrop"></div>' +
          '<div class="aksrt-captcha-modal-box"><div class="aksrt-captcha-modal-header">' +
          '<span class="aksrt-captcha-modal-title">人机验证</span>' +
          '<button type="button" class="aksrt-captcha-modal-close">&times;</button></div>' +
          '<div class="aksrt-captcha-modal-body"><p class="aksrt-captcha-modal-hint">请完成验证后继续操作</p>' +
          '<div id="modalWidget_' + C.uid + '" class="aksrt-captcha-modal-widget"></div></div></div></div>';
        document.body.appendChild(modal);
        var cancel = function () {
          verifying = false;
          closeModal();
          cancelPending('已取消验证');
        };
        modal.querySelector('.aksrt-captcha-modal-backdrop').addEventListener('click', cancel);
        modal.querySelector('.aksrt-captcha-modal-close').addEventListener('click', cancel);
        renderWidget();
      }

      window['onTurnstileLoad_' + C.uid] = function () {};
      if (typeof window.turnstile === 'undefined') {
        loadScriptOnce('cloudflare', 'https://challenges.cloudflare.com/turnstile/v0/api.js?onload=onTurnstileLoad_' + C.uid + '&render=explicit', function () {
          return typeof window.turnstile !== 'undefined';
        }).catch(function () { cancelPending('验证码组件加载失败，请刷新重试'); });
      }
      triggerCaptcha = function () {
        if (verifying) return;
        verifying = true;
        createModal();
      };
      providerReset = closeModal;
    }

    function loadGeetest() {
      showLoading();
      var captchaId = C.gt && C.gt.captcha_id ? String(C.gt.captcha_id).trim() : '';
      var product = C.gt && C.gt.product ? String(C.gt.product) : 'bind';
      if (!captchaId) {
        clearLoading();
        cancelPending('极验 Captcha ID 未配置');
        return;
      }

      function render() {
        clearLoading();
        window.initGeetest4({ captchaId: captchaId, product: product, hideSuccess: true }, function (captchaInstance) {
          function onSuccess() {
            var result = captchaInstance.getValidate();
            if (!result) { cancelPending('验证码失败，请重试'); return; }
            setField('geetest_lot_number', result.lot_number);
            setField('geetest_captcha_output', result.captcha_output);
            setField('geetest_pass_token', result.pass_token);
            setField('geetest_gen_time', result.gen_time);
            completeProviderVerification();
          }
          captchaInstance.onReady(function () {}).onSuccess(onSuccess).onClose(function () { cancelPending('已取消验证'); });
          if (product !== 'bind' && product !== 'popup') captchaInstance.appendTo('#' + C.uid);
          triggerCaptcha = function () {
            if (product === 'bind' || product === 'popup') captchaInstance.showCaptcha();
            else showTip('请先完成人机验证', '#e67e22');
          };
          providerReset = function () {
            if (typeof captchaInstance.reset === 'function') captchaInstance.reset();
          };
        });
      }

      if (typeof window.initGeetest4 === 'undefined') {
        loadScriptOnce('geetest', 'https://static.geetest.com/v4/gt4.js', function () {
          return typeof window.initGeetest4 !== 'undefined';
        }).then(render).catch(function () {
          clearLoading();
          cancelPending('极验组件加载失败');
        });
      } else {
        render();
      }
    }

    function loadAliyun() {
      showLoading();
      window.AliyunCaptchaConfig = { region: C.al.region || 'cn', prefix: C.al.prefix };

      function render() {
        clearLoading();
        var captchaInstance = null;
        window.initAliyunCaptcha({
          SceneId: C.al.scene_id,
          mode: 'popup',
          element: '#' + C.uid,
          success: function (verifyParam) {
            setField('aliyun_captcha_verify_param', verifyParam);
            completeProviderVerification();
          },
          fail: function () { cancelPending('验证码失败，请重试'); },
          getInstance: function (value) { captchaInstance = value; },
          slideStyle: { width: 360, height: 40 },
          language: 'cn'
        });
        triggerCaptcha = function () {
          if (captchaInstance && captchaInstance.show) captchaInstance.show();
          else cancelPending('验证码组件加载中，请稍候再试');
        };
        providerReset = function () {
          if (captchaInstance && typeof captchaInstance.reset === 'function') captchaInstance.reset();
        };
      }

      if (typeof window.initAliyunCaptcha === 'undefined') {
        loadScriptOnce('aliyun', 'https://o.alicdn.com/captcha-frontend/aliyunCaptcha/AliyunCaptcha.js', function () {
          return typeof window.initAliyunCaptcha !== 'undefined';
        }).then(render).catch(function () {
          clearLoading();
          cancelPending('验证码组件加载失败，请刷新重试');
        });
      } else {
        render();
      }
    }

    switch (C.provider) {
      case 'tencent': loadTencent(); break;
      case 'cloudflare': loadCloudflare(); break;
      case 'geetest': loadGeetest(); break;
      case 'aliyun': loadAliyun(); break;
    }
  }

  window.AksrtFrontend.register('aksrt-captcha-front', scan);
})();