// ====== Text-to-Speech for Blogger (Language Picker, External JS) ======
// Self-contained: injects its own controls & styles above each post (.post-body)
(function(){
  const STORAGE_KEY_LANG = 'crml_tts_lang_v1';   // remember language choice

  // ---- Inject minimal CSS once ----
  (function injectCSS(){
    if (document.getElementById('crml-tts-style')) return;
    const css = `
      .crml-actions{background:#fff0c2;padding:12px 14px;border-radius:14px;display:flex;gap:10px;align-items:center;flex-wrap:wrap;margin:12px 0;box-shadow:0 2px 6px rgba(0,0,0,.06)}
      .crml-label{font-size:13px;opacity:.85}
      .crml-select{appearance:none;padding:8px 12px;border-radius:12px;border:1px solid #d7dde3;background:#fff;font-size:14px}
      .crml-btn{border:0;border-radius:16px;padding:10px 16px;font-weight:600;font-size:14px;cursor:pointer;display:inline-flex;gap:8px;align-items:center;box-shadow:0 2px 4px rgba(0,0,0,.06);background:#2787f5;color:#fff}
      .crml-btn:disabled{opacity:.5;cursor:not-allowed}
      .crml-btn:active{transform:translateY(1px)}
      .crml-btn-stop{background:#FF6C00 !important;color:#fff !important}
    `;
    const style = document.createElement('style');
    style.id = 'crml-tts-style';
    style.textContent = css;
    document.head.appendChild(style);
  })();

  const TTS = {
    utter: null,
    state: 'idle', // idle | playing | paused
    voices: [],
    byLang: new Map(),

    loadVoices(){
      this.voices = window.speechSynthesis.getVoices() || [];
      this.byLang.clear();
      this.voices.forEach(v=>{
        const L = (v.lang || '').trim();
        if (!this.byLang.has(L)) this.byLang.set(L, []);
        this.byLang.get(L).push(v);
      });
    },

    pickVoice(langHint){
      const vs = this.voices.length ? this.voices : window.speechSynthesis.getVoices();
      const lang = (langHint||'').toLowerCase();

      // exact match (e.g., el-GR)
      let v = vs.find(v => (v.lang||'').toLowerCase() === lang);
      if (v) return v;

      // base language match (e.g., el-*)
      const base = lang.split('-')[0];
      v = vs.find(v => (v.lang||'').toLowerCase().startsWith(base));
      if (v) return v;

      // heuristics for Greek / English
      if (base === 'el'){
        v = vs.find(v => /greek/i.test(v.name||'')) || vs.find(v => (v.lang||'').toLowerCase().startsWith('el'));
        if (v) return v;
      }
      if (base === 'en'){
        v = vs.find(v => /^en-(gb|us)/i.test(v.lang||'')) || vs.find(v => (v.lang||'').toLowerCase().startsWith('en'));
        if (v) return v;
      }

      // fallback
      return vs[0] || null;
    },

    textFrom(root){
      const body = root.querySelector('.post-body,[itemprop="articleBody"]')
                || document.querySelector('.post-body,[itemprop="articleBody"]');
      const c = (body ? body.cloneNode(true) : null);
      if (!c) return '';
      c.querySelectorAll('script,style,noscript,iframe,svg,canvas,.MathJax,mjx-container').forEach(n=>n.remove());
      let text = (c.innerText || '').replace(/\s+\n/g,'\n').replace(/\n{3,}/g,'\n\n').trim();
      if (text.length>100000) text = text.slice(0,100000);
      return text;
    },

    getChosenLang(selectEl){
      const v = (selectEl && selectEl.value) ? selectEl.value : '__auto__';
      if (v && v !== '__auto__') return v;

      const htmlLang = (document.documentElement.lang || '').trim();
      const navLang  = (navigator.language || 'en-US');
      const langs    = Array.from(this.byLang.keys());
      const pick = want => langs.find(L => L.toLowerCase().startsWith(want.toLowerCase().split('-')[0]));
      return pick(htmlLang) || pick(navLang) || 'en-US';
    },

    start(btn){
      if (!('speechSynthesis' in window)) { alert('Ο browser δεν υποστηρίζει Text-to-Speech.'); return; }
      const row  = btn.closest('.crml-actions') || btn.parentElement || document;
      const langSelect = row.querySelector('[data-tts="lang"]');
      const root = btn.closest('.post') || document;
      const text = this.textFrom(root);
      if (!text) { alert('Δεν βρέθηκε κείμενο για ανάγνωση.'); return; }

      window.speechSynthesis.cancel();
      this.loadVoices();

      const chosenLang = this.getChosenLang(langSelect);
      const u = new SpeechSynthesisUtterance(text);
      u.lang   = chosenLang;
      u.rate   = 1;
      u.pitch  = 1;
      const voice = this.pickVoice(chosenLang);
      if (voice) u.voice = voice;

      u.onstart = ()=>{ this.state='playing'; this.updateButtons(btn,'playing'); };
      u.onend   = ()=>{ this.state='idle';    this.updateButtons(btn,'idle');    };
      u.onerror = ()=>{ this.state='idle';    this.updateButtons(btn,'idle');    };

      try { localStorage.setItem(STORAGE_KEY_LANG, langSelect ? (langSelect.value || '__auto__') : '__auto__'); } catch(e){}

      this.utter = u;
      window.speechSynthesis.speak(u);
    },

    toggle(btn){
      if (!('speechSynthesis' in window)) { alert('Ο browser δεν υποστηρίζει Text-to-Speech.'); return; }
      if (this.state==='playing'){
        window.speechSynthesis.pause();
        this.state='paused';
        this.updateButtons(btn,'paused');
      } else if (this.state==='paused'){
        window.speechSynthesis.resume();
        this.state='playing';
        this.updateButtons(btn,'playing');
      } else {
        this.start(btn);
      }
    },

    stop(btn){
      window.speechSynthesis.cancel();
      this.state='idle';
      this.updateButtons(btn,'idle');
    },

    updateButtons(anyBtn,state){
      const row = anyBtn.closest('.crml-actions') || anyBtn.parentElement;
      const playBtn = row ? row.querySelector('[data-tts="toggle"]') : null;
      const stopBtn = row ? row.querySelector('[data-tts="stop"]') : null;
      if (!playBtn || !stopBtn) return;

      if (state==='playing'){
        playBtn.textContent = '⏸️ Παύση';
        stopBtn.removeAttribute('disabled');
      } else if (state==='paused'){
        playBtn.textContent = '▶️ Συνέχεια';
        stopBtn.removeAttribute('disabled');
      } else {
        playBtn.textContent = '🔊 Listen';
        stopBtn.setAttribute('disabled','disabled');
      }
    }
  };

  window.CRML_TTS = TTS;

  if ('speechSynthesis' in window){
    window.speechSynthesis.onvoiceschanged = function(){
      window.CRML_TTS.loadVoices();
    };
  }

  function buildLangOptions(){
    const saved = (function(){ try { return localStorage.getItem(STORAGE_KEY_LANG) || '__auto__'; } catch(e){ return '__auto__'; } })();
    const sel = document.createElement('select');
    sel.setAttribute('data-tts','lang');
    sel.className = 'crml-select';
    sel.innerHTML = '<option value="__auto__">Auto</option>';
    TTS.loadVoices();
    const langs = Array.from(TTS.byLang.keys()).sort((a,b)=>a.localeCompare(b));
    langs.forEach(L=>{
      const opt = document.createElement('option');
      opt.value = L;
      opt.textContent = L;
      sel.appendChild(opt);
    });
    sel.value = saved;
    sel.title = 'Επιλογή γλώσσας αναπαραγωγής';
    return sel;
  }

  function makeRow(){
    const row = document.createElement('div');
    row.className = 'crml-actions';

    const langLabel = document.createElement('span');
    langLabel.textContent = 'Language: ';
    langLabel.className = 'crml-label';

    const sel = buildLangOptions();

    const btnPlay = document.createElement('button');
    btnPlay.className = 'crml-btn';
    btnPlay.setAttribute('data-tts','toggle');
    btnPlay.textContent = '🔊 Listen';
    btnPlay.onclick = function(){ CRML_TTS.toggle(this); };

    const btnStop = document.createElement('button');
    btnStop.className = 'crml-btn crml-btn-stop';
    btnStop.setAttribute('data-tts','stop');
    btnStop.setAttribute('disabled','disabled');
    btnStop.textContent = '■ Stop';
    btnStop.onclick = function(){ CRML_TTS.stop(this); };

    row.appendChild(langLabel);
    row.appendChild(sel);
    row.appendChild(btnPlay);
    row.appendChild(btnStop);
    return row;
  }

  function injectOnce(postRoot){
    if (!postRoot) return;
    if (postRoot.querySelector('.crml-actions')) return;
    const body = postRoot.querySelector('.post-body,[itemprop="articleBody"]') || postRoot;
    const row = makeRow();
    if (body && body.parentElement) {
      body.parentElement.insertBefore(row, body);
    }
  }

  function findPostRoots(){
    const roots = new Set();
    document.querySelectorAll('.post, article, .post-outer, [itemtype*="Article"], .blog-posts')
      .forEach(node=>{
        const root = node.closest('.post, article, .post-outer') || node;
        if (root) roots.add(root);
      });
    if (roots.size===0) {
      document.querySelectorAll('.post-body,[itemprop="articleBody"]').forEach(b=>{
        roots.add(b.parentElement || b);
      });
    }
    return Array.from(roots);
  }

  function init(){
    const posts = findPostRoots();
    posts.forEach(injectOnce);
  }

  if (document.readyState === 'loading') {
    document.addEventListener('DOMContentLoaded', init);
  } else {
    init();
  }
  new MutationObserver(()=>init()).observe(document.documentElement, {childList:true, subtree:true});
})();