/* FeedLite · 轻反馈 —— 轻量交互（图片/视频上传：经服务器中转落地，前端对 local/OSS 走同一路径） */
(function () {
  'use strict';

  /* ---------- 公共小工具 ---------- */
  function $(sel, root) { return (root || document).querySelector(sel); }
  function $$(sel, root) {
    var out = [], list = (root || document).querySelectorAll(sel);
    for (var i = 0; i < list.length; i++) { out.push(list[i]); }
    return out;
  }
  function qs(obj) {
    var parts = [];
    for (var k in obj) {
      if (obj.hasOwnProperty(k) && obj[k] !== undefined && obj[k] !== null) {
        parts.push(encodeURIComponent(k) + '=' + encodeURIComponent(obj[k]));
      }
    }
    return parts.join('&');
  }
  function human(bytes) {
    var b = Number(bytes) || 0;
    if (b < 1024) { return b + ' B'; }
    if (b < 1048576) { return (b / 1024).toFixed(1) + ' KB'; }
    return (b / 1048576).toFixed(1) + ' MB';
  }
  function extByMime(mime) {
    if (mime === 'image/webp') { return 'webp'; }
    if (mime === 'image/png') { return 'png'; }
    if (mime === 'image/gif') { return 'gif'; }
    if (mime === 'video/mp4') { return 'mp4'; }
    if (mime === 'video/quicktime') { return 'mov'; }
    if (mime === 'video/webm') { return 'webm'; }
    return 'jpg';
  }
  function renameExt(name, mime) {
    var base = String(name || 'file').replace(/\.[A-Za-z0-9]{1,8}$/, '') || 'file';
    return base + '.' + extByMime(mime);
  }

  /* ---------- 换一题：AJAX 刷新验证题，不丢失已填内容 ---------- */
  function bindCaptchaRefresh() {
    var links = document.querySelectorAll('[data-captcha-refresh]');
    for (var i = 0; i < links.length; i++) {
      links[i].addEventListener('click', function (e) {
        e.preventDefault();
        var box = this.closest('.captcha-line');
        var qEl = box ? box.querySelector('.c-q') : null;
        var input = box ? box.querySelector('input[name=captcha]') : null;
        var self = this;
        self.style.opacity = '.5';
        fetch('captcha.php', { credentials: 'same-origin' })
          .then(function (r) { return r.json(); })
          .then(function (d) {
            if (d && d.ok && qEl) { qEl.textContent = d.q; }
            if (input) { input.value = ''; input.focus(); }
          })
          .catch(function () { window.location.href = 'captcha.php'; })
          .then(function () { self.style.opacity = '1'; });
      });
    }
  }

  /* ---------- 管理员口令：填写后显示"处理状态"，并解除邮箱必填 ---------- */
  function bindAdminToggle() {
    var pw = document.querySelector('input[name=admin_password]');
    if (!pw) { return; }
    var statusBox = document.querySelector('.admin-status');
    var emailInput = document.querySelector('input[name=email]');
    var emailField = document.getElementById('emailField');

    function sync() {
      var isAdmin = pw.value.trim() !== '';
      if (statusBox) { statusBox.hidden = !isAdmin; }
      if (emailInput) {
        emailInput.required = !isAdmin;
        if (isAdmin) { emailInput.removeAttribute('required'); }
      }
      if (emailField) {
        var req = emailField.querySelector('.req');
        if (req) { req.style.visibility = isAdmin ? 'hidden' : 'visible'; }
      }
    }
    pw.addEventListener('input', sync);
    sync();
  }

  /* ---------- 防止重复提交（上传未完成时阻止提交） ---------- */
  function bindNoDoubleSubmit() {
    var forms = document.querySelectorAll('form');
    for (var i = 0; i < forms.length; i++) {
      forms[i].addEventListener('submit', function (ev) {
        var box = this.querySelector('[data-uploader-root]');
        if (box && Number(box.getAttribute('data-pending') || 0) > 0) {
          ev.preventDefault();
          alert('还有文件正在上传，请等待上传完成后再提交。');
          return;
        }
        var btn = this.querySelector('button[type=submit]');
        if (btn) {
          setTimeout(function () { btn.disabled = true; btn.style.opacity = '.6'; }, 0);
          setTimeout(function () { btn.disabled = false; btn.style.opacity = '1'; }, 5000);
        }
      });
    }
  }

  /* ---------- 图片压缩（canvas，保留动图） ---------- */
  function prepareImage(file, maxSide) {
    return new Promise(function (resolve) {
      // GIF 可能带动画，压缩会丢失动画 —— 原样上传
      if (file.type === 'image/gif') {
        resolve({ blob: file, mime: file.type, name: file.name });
        return;
      }
      var url = URL.createObjectURL(file);
      var img = new Image();
      img.onload = function () {
        var w = img.naturalWidth, h = img.naturalHeight;
        var scale = Math.min(1, maxSide / Math.max(w, h));
        var tw = Math.max(1, Math.round(w * scale));
        var th = Math.max(1, Math.round(h * scale));
        var small = file.size <= 600 * 1024;
        if (small && scale >= 1) {
          URL.revokeObjectURL(url);
          resolve({ blob: file, mime: file.type, name: file.name });
          return;
        }
        var cv = document.createElement('canvas');
        cv.width = tw; cv.height = th;
        cv.getContext('2d').drawImage(img, 0, 0, tw, th);

        var prefer = (file.type === 'image/png' || file.type === 'image/webp') ? 'image/webp' : 'image/jpeg';
        var quality = 0.82;

        function done(blob, mime) {
          URL.revokeObjectURL(url);
          if (!blob || (blob.size >= file.size && small)) {
            resolve({ blob: file, mime: file.type, name: file.name });
            return;
          }
          var real = blob.type || mime;
          resolve({ blob: blob, mime: real, name: renameExt(file.name, real) });
        }
        cv.toBlob(function (blob) {
          if (blob && blob.type !== prefer) {
            cv.toBlob(function (b2) { done(b2, 'image/jpeg'); }, 'image/jpeg', quality);
          } else {
            done(blob, prefer);
          }
        }, prefer, quality);
      };
      img.onerror = function () {
        URL.revokeObjectURL(url);
        resolve({ blob: file, mime: file.type, name: file.name });
      };
      img.src = url;
    });
  }

  /* ---------- 附件上传（经服务器中转，local/OSS 同一路径） ---------- */
  function initUploaderRoot(root) {
    var csrf    = root.getAttribute('data-csrf') || '';
    var signUrl = root.getAttribute('data-sign-url') || 'upload.php';
    var field   = root.querySelector('.att-field');
    var state   = [];      // 已成功的附件描述
    var pending = 0;

    try {
      var init = JSON.parse(root.getAttribute('data-init') || '[]');
      for (var i = 0; i < init.length; i++) { state.push(init[i]); }
    } catch (e) { /* 忽略 */ }

    function setPending(n) {
      pending = Math.max(0, pending + n);
      root.setAttribute('data-pending', String(pending));
    }

    function sync() {
      if (!field) { return; }
      var out = [];
      for (var i = 0; i < state.length; i++) {
        var s = state[i];
        out.push({ kind: s.kind, key: s.key, size: s.size, name: s.name || '', mime: s.mime || '', w: s.w || 0, h: s.h || 0 });
      }
      field.value = out.length ? JSON.stringify(out) : '';
    }

    function countOf(kind) {
      var n = 0;
      for (var i = 0; i < state.length; i++) { if (state[i].kind === kind) { n++; } }
      return n;
    }

    function makeNode(box, meta) {
      var list = box.querySelector('.up-list');
      var el = document.createElement('div');
      el.className = 'up-item' + (meta.kind === 'video' ? ' video' : '');

      var thumb = document.createElement('div');
      thumb.className = 'up-thumb';
      if (meta.kind === 'image') {
        var im = document.createElement('img');
        im.alt = '';
        if (meta.thumb) { im.src = meta.thumb; }
        thumb.appendChild(im);
      } else {
        thumb.classList.add('up-thumb-video');
        thumb.textContent = 'VIDEO';
      }

      var info = document.createElement('div');
      info.className = 'up-info';
      var nm = document.createElement('div');
      nm.className = 'up-name';
      nm.textContent = meta.name || (meta.kind === 'image' ? '图片' : '视频');
      var st = document.createElement('div');
      st.className = 'up-state';
      st.textContent = '等待上传…';
      var bar = document.createElement('div');
      bar.className = 'up-bar';
      var fill = document.createElement('i');
      bar.appendChild(fill);
      info.appendChild(nm); info.appendChild(st); info.appendChild(bar);

      var rm = document.createElement('button');
      rm.type = 'button';
      rm.className = 'up-del';
      rm.textContent = '移除';

      el.appendChild(thumb); el.appendChild(info); el.appendChild(rm);
      list.appendChild(el);
      return { el: el, fill: fill, st: st, rm: rm, thumb: thumb };
    }

    function removeItem(node, item) {
      if (node && node.el && node.el.parentNode) { node.el.parentNode.removeChild(node.el); }
      if (item) {
        for (var i = 0; i < state.length; i++) {
          if (state[i].key === item.key) { state.splice(i, 1); break; }
        }
      }
      sync();
    }

    function sign(kind, ext, size, mime) {
      return fetch(signUrl, {
        method: 'POST',
        credentials: 'same-origin',
        headers: { 'Content-Type': 'application/x-www-form-urlencoded;charset=UTF-8' },
        body: qs({ csrf: csrf, kind: kind, ext: ext, size: size, mime: mime })
      }).then(function (r) {
        return r.json().catch(function () { throw new Error('服务器返回异常（' + r.status + '）'); });
      }).then(function (d) {
        if (!d || !d.ok) { throw new Error((d && d.error) || '获取上传凭证失败'); }
        return d;
      });
    }

    function upload(cred, fields, blob, filename, onProgress) {
      return new Promise(function (resolve, reject) {
        var fd = new FormData();
        for (var k in fields) {
          if (fields.hasOwnProperty(k)) { fd.append(k, fields[k]); }
        }
        fd.append('file', blob, filename);          // 文件必须是最后一个字段

        var xhr = new XMLHttpRequest();
        xhr.open('POST', cred.host, true);
        xhr.upload.onprogress = function (e) {
          if (e.lengthComputable && onProgress) { onProgress(e.loaded / e.total); }
        };
        xhr.onload = function () {
          if (xhr.status === 200 || xhr.status === 204) { resolve(true); }
          else {
            var msg = String(xhr.responseText || '').replace(/<[^>]*>/g, ' ').slice(0, 160).trim();
            reject(new Error('上传到存储失败（' + xhr.status + '）' + (msg ? '：' + msg : '')));
          }
        };
        xhr.onerror = function () { reject(new Error('网络异常，上传中断')); };
        xhr.send(fd);
      });
    }

    async function handleFiles(box, files) {
      var kind     = box.getAttribute('data-kind') || 'image';
      var maxCount = parseInt(box.getAttribute('data-max-count') || '1', 10);
      var maxBytes = parseInt(box.getAttribute('data-max-bytes') || '0', 10);
      var maxSide  = parseInt(box.getAttribute('data-max-side') || '1600', 10);
      var label    = box.getAttribute('data-label') || '附件';
      var allowed  = (box.getAttribute('data-accept') || '').split(',');

      for (var i = 0; i < files.length; i++) {
        var file = files[i];

        if (allowed.length && allowed.indexOf(file.type) < 0) {
          alert('「' + file.name + '」格式不支持，请选择：' + allowed.join(' / '));
          continue;
        }
        if (maxBytes > 0 && file.size > maxBytes) {
          alert('「' + file.name + '」超过 ' + human(maxBytes) + ' 上限。');
          continue;
        }
        if (countOf(kind) >= maxCount) {
          alert(label + '最多上传 ' + maxCount + ' 个，请先移除已上传的文件。');
          break;
        }

        var node = makeNode(box, { kind: kind, name: file.name, thumb: '' });
        setPending(1);
        node.rm.disabled = true;

        try {
          node.st.textContent = '处理中…';
          var prepared;
          if (kind === 'image') {
            prepared = await prepareImage(file, maxSide);
            if (prepared.blob !== file && prepared.blob.size > 0) {
              node.st.textContent = '已压缩 ' + human(file.size) + ' → ' + human(prepared.blob.size);
              try { node.thumb.querySelector('img').src = URL.createObjectURL(prepared.blob); } catch (e2) { /* 忽略 */ }
            }
          } else {
            prepared = { blob: file, mime: file.type, name: file.name };
          }

          var ext = extByMime(prepared.mime);
          var d   = await sign(kind, ext, prepared.blob.size, prepared.mime);

          node.st.textContent = '上传中…';
          await upload(d.credential, d.fields, prepared.blob, prepared.name, function (p) {
            node.fill.style.width = Math.round(p * 100) + '%';
            node.st.textContent = '上传中 ' + Math.round(p * 100) + '%';
          });

          var item = {
            kind: kind,
            key: d.credential.key,
            size: prepared.blob.size,
            name: prepared.name,
            mime: prepared.mime,
            w: 0, h: 0,
            thumb: d.credential.url || ''
          };
          state.push(item);
          sync();

          node.el.classList.add('done');
          node.fill.style.width = '100%';
          node.st.textContent = '已上传 · ' + human(item.size);
          if (kind === 'image' && item.thumb) {
            var imgEl = node.thumb.querySelector('img');
            if (imgEl) { imgEl.src = item.thumb; }
          }
          node.rm.disabled = false;
          node.rm.addEventListener('click', function (it) {
            return function () { removeItem(node, it); };
          }(item));
        } catch (e) {
          node.el.classList.add('fail');
          node.st.textContent = (e && e.message) ? e.message : '上传失败';
          node.rm.textContent = '删除';
          node.rm.disabled = false;
          node.rm.addEventListener('click', function () { removeItem(node, null); });
        } finally {
          setPending(-1);
        }
      }
    }

    // 回填服务端已保存的附件（校验失败后重新提交时）
    var byKind = {};
    for (var s = 0; s < state.length; s++) {
      var it0 = state[s];
      var box0 = root.querySelector('[data-uploader][data-kind="' + it0.kind + '"]');
      if (!box0) { continue; }
      byKind[it0.kind] = (byKind[it0.kind] || 0) + 1;
      var nd = makeNode(box0, it0);
      nd.el.classList.add('done');
      nd.fill.style.width = '100%';
      nd.st.textContent = '已上传 · ' + human(it0.size);
      nd.rm.addEventListener('click', function (item, node) {
        return function () { removeItem(node, item); };
      }(it0, nd));
    }
    sync();

    var boxes = $$('[data-uploader]', root);
    for (var b = 0; b < boxes.length; b++) {
      (function (box) {
        var pick  = box.querySelector('.up-pick');
        var input = box.querySelector('.up-file');
        if (!pick || !input) { return; }
        pick.addEventListener('click', function () { input.click(); });
        input.addEventListener('change', function () {
          var files = [];
          for (var k = 0; k < input.files.length; k++) { files.push(input.files[k]); }
          input.value = '';
          if (files.length) { handleFiles(box, files); }
        });
        // 拖拽上传
        ['dragenter', 'dragover'].forEach(function (ev) {
          box.addEventListener(ev, function (e) { e.preventDefault(); box.classList.add('dragging'); });
        });
        ['dragleave', 'drop'].forEach(function (ev) {
          box.addEventListener(ev, function (e) { e.preventDefault(); box.classList.remove('dragging'); });
        });
        box.addEventListener('drop', function (e) {
          e.preventDefault();
          var files = [];
          if (e.dataTransfer && e.dataTransfer.files) {
            for (var k = 0; k < e.dataTransfer.files.length; k++) { files.push(e.dataTransfer.files[k]); }
          }
          if (files.length) { handleFiles(box, files); }
        });
      }(boxes[b]));
    }
  }

  function bindUploaders() {
    var roots = $$('[data-uploader-root]');
    for (var i = 0; i < roots.length; i++) { initUploaderRoot(roots[i]); }
  }

  /* ---------- 附件灯箱：点击放大 + 左右切换 ---------- */
  function bindLightbox() {
    var galleries = $$('[data-gallery]');
    if (!galleries.length) { return; }

    var ov = null, items = [], cur = 0, lastFocus = null, built = false;
    var media = null, nameEl = null, metaEl = null, origEl = null, prevBtn = null, nextBtn = null;

    function buildOverlay() {
      ov = document.createElement('div');
      ov.className = 'lb';
      ov.hidden = true;
      ov.setAttribute('role', 'dialog');
      ov.setAttribute('aria-modal', 'true');
      ov.setAttribute('aria-label', '附件查看');
      ov.innerHTML =
        '<button type="button" class="lb-x" aria-label="关闭">✕</button>' +
        '<div class="lb-stage">' +
          '<button type="button" class="lb-nav lb-prev" aria-label="上一个">‹</button>' +
          '<div class="lb-media"></div>' +
          '<button type="button" class="lb-nav lb-next" aria-label="下一个">›</button>' +
        '</div>' +
        '<div class="lb-bar">' +
          '<span class="lb-name"></span>' +
          '<span class="lb-meta"></span>' +
          '<a class="lb-orig" href="#" target="_blank" rel="noopener noreferrer">查看原图</a>' +
        '</div>';
      document.body.appendChild(ov);

      media   = $('.lb-media', ov);
      nameEl  = $('.lb-name', ov);
      metaEl  = $('.lb-meta', ov);
      origEl  = $('.lb-orig', ov);
      prevBtn = $('.lb-prev', ov);
      nextBtn = $('.lb-next', ov);

      $('.lb-x', ov).addEventListener('click', close);
      prevBtn.addEventListener('click', function () { go(-1); });
      nextBtn.addEventListener('click', function () { go(1); });
      ov.addEventListener('click', function (e) {
        // 点空白处（遮罩本身或图片外的区域）关闭
        if (e.target === ov || e.target === media) { close(); }
      });

      // 触摸左右滑动
      var tx = 0, ty = 0, tracking = false;
      ov.addEventListener('touchstart', function (e) {
        if (!e.touches || e.touches.length !== 1) { tracking = false; return; }
        tx = e.touches[0].clientX; ty = e.touches[0].clientY; tracking = true;
      }, { passive: true });
      ov.addEventListener('touchend', function (e) {
        if (!tracking || !e.changedTouches || !e.changedTouches.length) { return; }
        tracking = false;
        var dx = e.changedTouches[0].clientX - tx;
        var dy = e.changedTouches[0].clientY - ty;
        if (Math.abs(dx) < 40 || Math.abs(dx) < Math.abs(dy)) { return; }
        go(dx < 0 ? 1 : -1);   // 左滑＝看下一个，与浏览图片的直觉一致
      }, { passive: true });

      document.addEventListener('keydown', function (e) {
        if (!ov || ov.hidden) { return; }
        var k = e.key;
        if (k === 'Escape') { close(); }
        else if (k === 'ArrowLeft') { go(-1); }
        else if (k === 'ArrowRight') { go(1); }
        else if (k === 'Home') { cur = 0; render(); }
        else if (k === 'End') { cur = items.length - 1; render(); }
        else { return; }
        e.preventDefault();
      });
    }

    function render() {
      if (!items.length) { return; }
      var it = items[cur];
      media.className = 'lb-media loading';
      media.innerHTML = '';

      var node;
      if (it.kind === 'video') {
        node = document.createElement('video');
        node.controls = true;
        node.autoplay = true;
        node.playsInline = true;
        node.setAttribute('playsinline', '');
        node.src = it.src;
        if (it.poster) { node.poster = it.poster; }
      } else {
        node = document.createElement('img');
        node.alt = it.name || '';
        node.src = it.src;
      }
      function ready() { media.classList.remove('loading'); }
      node.addEventListener('load', ready);
      node.addEventListener('loadeddata', ready);
      node.addEventListener('error', ready);
      media.appendChild(node);

      nameEl.textContent = it.name || (it.kind === 'video' ? '视频' : '图片');
      metaEl.textContent = (cur + 1) + ' / ' + items.length + (it.size ? ' · ' + it.size : '');
      if (it.kind === 'video') {
        origEl.hidden = true;
      } else {
        origEl.hidden = false;
        origEl.href = it.full || it.src;
      }

      var multi = items.length > 1;
      prevBtn.hidden = !multi;
      nextBtn.hidden = !multi;

      // 预载相邻图片，切换时更快
      if (multi) {
        var nb = [items[(cur + 1) % items.length], items[(cur - 1 + items.length) % items.length]];
        for (var i = 0; i < nb.length; i++) {
          if (nb[i].kind === 'image' && nb[i].src) { (new Image()).src = nb[i].src; }
        }
      }
    }

    function go(step) {
      if (items.length < 2) { return; }
      cur = (cur + step + items.length) % items.length;
      render();
    }

    function open(list, idx) {
      if (!built) { buildOverlay(); built = true; }
      if (!list.length) { return; }
      items = list;
      cur = Math.max(0, Math.min(idx, list.length - 1));
      lastFocus = document.activeElement;

      // 打开灯箱时暂停正文里的内嵌视频，避免两个声音一起响
      var inline = document.querySelectorAll('.atts video');
      for (var i = 0; i < inline.length; i++) { try { inline[i].pause(); } catch (e) {} }

      ov.hidden = false;
      document.documentElement.classList.add('lb-open');
      document.body.classList.add('lb-open');
      render();
      var x = $('.lb-x', ov);
      if (x) { x.focus(); }
    }

    function close() {
      if (!ov || ov.hidden) { return; }
      ov.hidden = true;
      media.innerHTML = '';          // 顺带停止灯箱里的视频播放
      document.documentElement.classList.remove('lb-open');
      document.body.classList.remove('lb-open');
      if (lastFocus && lastFocus.focus) { try { lastFocus.focus(); } catch (e) {} }
    }

    // 收集一个画廊里的全部附件（按 DOM 顺序）
    function itemsOf(gal) {
      var els = $$('[data-lb-kind]', gal), out = [];
      for (var i = 0; i < els.length; i++) {
        var el = els[i];
        out.push({
          kind:   el.getAttribute('data-lb-kind') || 'image',
          src:    el.getAttribute('data-lb-src') || el.getAttribute('href') || '',
          full:   el.getAttribute('data-lb-full') || '',
          poster: el.getAttribute('data-lb-poster') || '',
          name:   el.getAttribute('data-lb-name') || '',
          size:   el.getAttribute('data-lb-size') || ''
        });
      }
      return out;
    }

    for (var g = 0; g < galleries.length; g++) {
      (function (gal) {
        gal.addEventListener('click', function (e) {
          var t = e.target, trigger = null;
          while (t && t !== gal) {
            if (t.getAttribute && t.getAttribute('data-lb-kind')) { trigger = t; break; }
            t = t.parentNode;
          }
          if (!trigger) { return; }
          e.preventDefault();                       // 图片是 <a>，有 JS 时就在页内放大

          var all = $$('[data-lb-kind]', gal), idx = 0;
          for (var i = 0; i < all.length; i++) { if (all[i] === trigger) { idx = i; break; } }
          open(itemsOf(gal), idx);
        });
      }(galleries[g]));
    }
  }

  function boot() {
    bindCaptchaRefresh();
    bindAdminToggle();
    bindNoDoubleSubmit();
    bindUploaders();
    bindLightbox();
  }

  if (document.readyState === 'loading') {
    document.addEventListener('DOMContentLoaded', boot);
  } else {
    boot();
  }
})();