/**
 * Alpine アプリ本体。単元データは ./data/categories.js と ./data/drills.js。
 *
 * HTML 方針:
 * - マークアップを描画する箇所は x-html="safeHtml(...)" のみ。
 * - タグを出さない一行表示には plainText(...)（サニタイズ後に textContent 化）。
 * - 状態に保持する解説文字列は保存時に sanitizeStoredHtml で正規化。
 */
import { DRILLS } from './data/drills.js';
import { CATEGORIES } from './data/categories.js';

function sanitizeTrustedHtml(dirty) {
  if (dirty == null || dirty === '') return '';
  const s = String(dirty);
  if (typeof window.DOMPurify === 'undefined') {
    const d = document.createElement('div');
    d.textContent = s;
    return d.innerHTML;
  }
  return window.DOMPurify.sanitize(s, {
    USE_PROFILES: { html: true, svg: true, svgFilters: true },
    ALLOW_UNKNOWN_PROTOCOLS: false
  });
}

/** localStorage / 画面状態に載せる HTML 断片の正規化（表示前と同じルール） */
function sanitizeStoredHtml(html) {
  return sanitizeTrustedHtml(html);
}

/** サニタイズ済み HTML からプレーン文字列（x-text 向け） */
function plainTextFromSanitizedHtml(html) {
  if (html == null || html === '') return '';
  const d = document.createElement('div');
  d.innerHTML = sanitizeTrustedHtml(String(html));
  return (d.textContent || '').replace(/\s+/g, ' ').trim();
}

document.addEventListener('alpine:init', () => {
  Alpine.data('bokiApp', () => ({
    safeHtml(s) {
      return sanitizeTrustedHtml(s);
    },
    plainText(s) {
      return plainTextFromSanitizedHtml(s);
    },
    categories:[],
    currentUnit:null,
    quizState:{},
    search:'',
    sidebarOpen:false,
    isDark:true,
    progress:{},
    scores:{},
    wrongUnits:{},
    keys:['A','B','C','D','E'],
    // concept fold
    conceptExpanded:false,
    // step mode
    stepMode:false,
    stepStep:1,
    stepKpIdx:0,
    stepFlashRevealed:false,
    stepDrillIdx:0,
    stepDrillAnswered:false,
    stepDrillSelected:-1,
    // weak drill
    weakDrillActive:false,
    weakDrillUnits:[],
    weakDrillUnitIdx:0,
    weakDrillQuizState:{},
    weakDrillResults:[],
    weakDrillDone:false,

    init(){
      this.categories = CATEGORIES.map(cat=>({
        ...cat,
        units: cat.units.map(u=>({...u, catLabel:cat.label}))
      }));
      try{ this.progress = JSON.parse(localStorage.getItem('posimai-boki-progress')||'{}'); }
      catch{ this.progress = {}; }
      try{ this.scores = JSON.parse(localStorage.getItem('posimai-boki-scores')||'{}'); }
      catch{ this.scores = {}; }
      try{ this.wrongUnits = JSON.parse(localStorage.getItem('posimai-boki-wrong')||'{}'); }
      catch{ this.wrongUnits = {}; }
      const t = localStorage.getItem('posimai-boki-theme')||'system';
      this.isDark = t==='dark'||(t==='system'&&matchMedia('(prefers-color-scheme:dark)').matches);
      const uid=(new URLSearchParams(location.search).get('unit')||'').trim().toLowerCase();
      if(uid){
        const u=this.allUnits().find(x=>x.id===uid);
        if(u){ this.currentUnit=u; this.quizState={}; }
        else{ try{ const url=new URL(window.location.href); url.searchParams.delete('unit'); const q=url.searchParams.toString(); history.replaceState(null,'',url.pathname+(q?'?'+q:'')+url.hash); }catch(e){} }
      }
      this.syncUnitToUrl();
      this.$nextTick(()=>{ if(window.lucide) lucide.createIcons(); });
      if('serviceWorker' in navigator){
        navigator.serviceWorker.register('/sw.js').catch(()=>{});
      }
    },

    syncUnitToUrl(){
      try{
        const url=new URL(window.location.href);
        if(this.currentUnit&&this.currentUnit.id) url.searchParams.set('unit',this.currentUnit.id);
        else url.searchParams.delete('unit');
        const q=url.searchParams.toString();
        const path=url.pathname+(q?'?'+q:'')+url.hash;
        if(path!==window.location.pathname+window.location.search+window.location.hash)
          history.replaceState(null,'',path);
      }catch(e){}
    },

    goHome(){
      this.currentUnit=null;
      this.quizState={};
      this.conceptExpanded=false;
      this.stepMode=false;
      this.weakDrillActive=false;
      this.syncUnitToUrl();
      this.$nextTick(()=>{ if(window.lucide) lucide.createIcons(); });
    },

    get filteredCats(){
      if(!this.search) return this.categories;
      const q=this.search.toLowerCase();
      return this.categories.map(cat=>({
        ...cat,
        units:cat.units.filter(u=>u.title.toLowerCase().includes(q)||u.num.toLowerCase().includes(q))
      })).filter(cat=>cat.units.length>0);
    },

    get totalCount(){ return this.categories.reduce((s,c)=>s+c.units.length,0); },
    get doneCount(){ return Object.keys(this.progress).length; },
    get progressPct(){ return this.totalCount ? Math.round(this.doneCount/this.totalCount*100) : 0; },

    get quizAnswered(){
      let n=0;
      Object.values(this.quizState).forEach(s=>{ if(s) n++; });
      return n;
    },
    get quizCorrect(){
      let n=0;
      Object.values(this.quizState).forEach(s=>{ if(s?.correct) n++; });
      return n;
    },

    catPct(cat){
      if(!cat.units.length) return 0;
      return Math.round(cat.units.filter(u=>this.progress[u.id]).length/cat.units.length*100);
    },

    allUnits(){ return this.categories.flatMap(c=>c.units); },

    isDone(id){ return !!this.progress[id]; },
    markDone(){
      if(!this.currentUnit) return;
      this.progress[this.currentUnit.id]=true;
      localStorage.setItem('posimai-boki-progress',JSON.stringify(this.progress));
    },
    bestScore(id){
      const s=this.scores[id];
      if(!s) return '';
      return s.best+'/'+s.total;
    },
    scoreChipCls(id){
      const s=this.scores[id];
      if(!s) return 'zero';
      if(s.best===s.total) return '';
      if(s.best>=s.total*0.6) return 'partial';
      return 'zero';
    },
    saveScore(id,correct,total){
      const prev=this.scores[id];
      if(!prev||correct>prev.best){
        this.scores[id]={best:correct,total};
        localStorage.setItem('posimai-boki-scores',JSON.stringify(this.scores));
      }
    },
    get freqBadgeCls(){
      const f=this.currentUnit?.freq;
      if(f==='high') return 'badge badge-high';
      if(f==='mid') return 'badge badge-mid';
      return 'badge badge-base';
    },
    get freqLabel(){
      const f=this.currentUnit?.freq;
      if(f==='high') return '頻出';
      if(f==='mid') return '重要';
      return '基礎';
    },
    get diffLabel(){
      const d=this.currentUnit?.diff||1;
      return '難易度 '+'★'.repeat(d)+'☆'.repeat(3-d);
    },

    openUnit(unit){
      this.currentUnit=unit;
      this.quizState={};
      this.conceptExpanded=false;
      this.stepMode=false;
      this.syncUnitToUrl();
      this.$nextTick(()=>{
        if(window.lucide) lucide.createIcons();
        const m=document.getElementById('main');
        if(m) m.scrollTo({top:0,behavior:'smooth'});
      });
    },

    // Weak unit tracking
    hasWrong(id){ return !!this.wrongUnits[id]; },
    _onAllAnswered(){
      if(!this.currentUnit) return;
      const uid=this.currentUnit.id;
      const total=this.currentUnit.quiz?.length||0;
      const correct=Object.values(this.quizState).filter(s=>s?.correct).length;
      if(correct>=total){
        delete this.wrongUnits[uid];
      } else {
        this.wrongUnits[uid]=(this.wrongUnits[uid]||0)+1;
      }
      localStorage.setItem('posimai-boki-wrong',JSON.stringify(this.wrongUnits));
      this.wrongUnits={...this.wrongUnits};
    },
    get weakUnits(){
      return this.allUnits().filter(u=>this.wrongUnits[u.id]>0)
        .sort((a,b)=>(this.wrongUnits[b.id]||0)-(this.wrongUnits[a.id]||0));
    },
    get todayUnits(){
      const result=[];
      // P0-1: pick worst wrong unit
      const weak=this.weakUnits;
      if(weak.length>0) result.push({...weak[0], todayTag:'苦手'});
      // P0-2: pick first undone unit (skip if same as weak)
      const all=this.allUnits();
      const weakId=result[0]?.id;
      // First try units with wrong answers but done (review)
      const review=all.find(u=>!this.wrongUnits[u.id] && this.scores[u.id] && u.id!==weakId && !this.progress[u.id]);
      if(review) result.push({...review, todayTag:'復習'});
      // Otherwise first unlearned
      if(result.length<2){
        const next=all.find(u=>!this.progress[u.id] && u.id!==weakId && !result.find(r=>r.id===u.id));
        if(next) result.push({...next, todayTag:'未学習'});
      }
      return result;
    },

    // Quiz
    answered(qi){ return !!this.quizState[qi]; },
    doAnswer(qi,ci,correct,exp){
      if(this.quizState[qi]) return;
      this.quizState[qi]={selected:ci,correct:ci===correct,exp:sanitizeStoredHtml(exp)};
      this.quizState={...this.quizState};
      // Check if all questions answered
      const total=this.currentUnit?.quiz?.length||0;
      if(total>0 && Object.keys(this.quizState).length>=total){
        this._onAllAnswered();
      }
    },
    qCardCls(qi){
      const s=this.quizState[qi];
      if(!s) return '';
      return s.correct?'correct':'wrong';
    },
    choiceCls(qi,ci,correct){
      const s=this.quizState[qi];
      if(!s) return '';
      if(ci===s.selected && s.correct) return 'sel-ok';
      if(ci===s.selected && !s.correct) return 'sel-ng';
      if(ci===correct && !s.correct) return 'rev-ok';
      return '';
    },
    get scoreLabel(){
      const total=this.currentUnit?.quiz?.length||0;
      const answered=Object.keys(this.quizState).length;
      const correct=Object.values(this.quizState).filter(s=>s?.correct).length;
      if(!answered) return total+'問';
      return correct+'/'+answered+'問正解';
    },
    get allAnswered(){
      const total=this.currentUnit?.quiz?.length||0;
      return total>0 && Object.keys(this.quizState).length>=total;
    },
    get resultScore(){
      const correct=Object.values(this.quizState).filter(s=>s?.correct).length;
      const total=this.currentUnit?.quiz?.length||0;
      if(this.currentUnit) this.saveScore(this.currentUnit.id,correct,total);
      return correct+' / '+total;
    },
    get resultMsg(){
      const correct=Object.values(this.quizState).filter(s=>s?.correct).length;
      const total=this.currentUnit?.quiz?.length||0;
      if(correct===total) return '完璧です！次の単元へ進みましょう。';
      if(correct>=total*0.8) return 'よくできました。あと少しで完璧です。';
      if(correct>=total*0.6) return '合格ラインです。間違えた問題の解説を確認しましょう。';
      return '解説をよく読んで、もう一度チャレンジしてみましょう。';
    },
    resetQuiz(){ this.quizState={}; },

    // Navigation
    currentIdx(){ return this.allUnits().findIndex(u=>u.id===this.currentUnit?.id); },
    get hasPrev(){ return this.currentIdx()>0; },
    get hasNext(){ return this.currentIdx()<this.allUnits().length-1; },
    prevUnit(){
      const i=this.currentIdx();
      if(i>0) this.openUnit(this.allUnits()[i-1]);
    },
    nextUnit(){
      const i=this.currentIdx();
      const all=this.allUnits();
      if(i<all.length-1) this.openUnit(all[i+1]);
    },

    toggleTheme(){
      this.isDark=!this.isDark;
      const val=this.isDark?'dark':'light';
      document.documentElement.setAttribute('data-theme',val);
      localStorage.setItem('posimai-boki-theme',val);
    },

    // ---- Concept expand ----
    get conceptPreview(){
      const c=this.currentUnit?.concept||'';
      const i=c.indexOf('</p>');
      return i===-1 ? c : c.substring(0,i+4);
    },
    get conceptRest(){
      const c=this.currentUnit?.concept||'';
      const i=c.indexOf('</p>');
      return i===-1 ? '' : c.substring(i+4);
    },

    // ---- Weak drill ----
    get weakDrillCandidates(){
      return this.allUnits()
        .filter(u=>this.hasWrong(u.id))
        .sort((a,b)=>{
          const sa=this.scores[a.id]?.best||0;
          const sb=this.scores[b.id]?.best||0;
          return sa-sb;
        })
        .slice(0,5);
    },
    startWeakDrill(){
      this.weakDrillUnits=[...this.weakDrillCandidates];
      this.weakDrillUnitIdx=0;
      this.weakDrillQuizState={};
      this.weakDrillResults=[];
      this.weakDrillDone=false;
      this.weakDrillActive=true;
      this.$nextTick(()=>{ if(window.lucide) lucide.createIcons(); });
    },
    exitWeakDrill(){
      this.weakDrillActive=false;
      this.weakDrillDone=false;
      this.$nextTick(()=>{ if(window.lucide) lucide.createIcons(); });
    },
    get weakDrillCurrentUnit(){
      return this.weakDrillUnits[this.weakDrillUnitIdx]||null;
    },
    wdAnswered(qi){ return !!this.weakDrillQuizState[qi]; },
    wdQCardCls(qi){
      const s=this.weakDrillQuizState[qi];
      if(!s) return '';
      return s.correct?'correct':'wrong';
    },
    wdChoiceCls(qi,ci,correct){
      const s=this.weakDrillQuizState[qi];
      if(!s) return '';
      if(ci===s.selected&&s.correct) return 'sel-ok';
      if(ci===s.selected&&!s.correct) return 'sel-ng';
      if(ci===correct&&!s.correct) return 'rev-ok';
      return '';
    },
    doWeakDrillAnswer(qi,ci,correct,exp){
      if(this.weakDrillQuizState[qi]) return;
      this.weakDrillQuizState[qi]={selected:ci,correct:ci===correct,exp:sanitizeStoredHtml(exp)};
      this.weakDrillQuizState={...this.weakDrillQuizState};
    },
    get weakDrillAllAnswered(){
      const total=this.weakDrillCurrentUnit?.quiz?.length||0;
      return total>0 && Object.keys(this.weakDrillQuizState).length>=total;
    },
    get weakDrillUnitScore(){
      const correct=Object.values(this.weakDrillQuizState).filter(s=>s?.correct).length;
      const total=this.weakDrillCurrentUnit?.quiz?.length||0;
      return correct+' / '+total;
    },
    nextWeakDrillUnit(){
      const unit=this.weakDrillCurrentUnit;
      if(!unit) return;
      const correct=Object.values(this.weakDrillQuizState).filter(s=>s?.correct).length;
      const total=unit.quiz?.length||0;
      this.weakDrillResults.push({unitId:unit.id,num:unit.num,unitTitle:unit.title,correct,total});
      // Update wrong tracking
      if(correct>=total){
        delete this.wrongUnits[unit.id];
        localStorage.setItem('posimai-boki-wrong',JSON.stringify(this.wrongUnits));
        this.wrongUnits={...this.wrongUnits};
      }
      if(this.weakDrillUnitIdx<this.weakDrillUnits.length-1){
        this.weakDrillUnitIdx++;
        this.weakDrillQuizState={};
      } else {
        this.weakDrillDone=true;
      }
      this.$nextTick(()=>{ if(window.lucide) lucide.createIcons(); });
    },
    get weakDrillClearCount(){
      return this.weakDrillResults.filter(r=>r.correct>=r.total).length;
    },

    // ---- Step mode ----
    startStepMode(){
      this.stepMode=true;
      this.stepStep=1;
      this.stepKpIdx=0;
      this.resetFlashRevealState();
      this.stepDrillIdx=0;
      this.stepDrillAnswered=false;
      this.stepDrillSelected=-1;
      this.$nextTick(()=>{
        if(window.lucide) lucide.createIcons();
        const m=document.getElementById('main');
        if(m) m.scrollTo({top:0,behavior:'smooth'});
      });
    },
    /** 理解度を空にしてから 3 ステップ（Step3 で一貫した初回解答） */
    startStepModeClearQuiz(){
      this.quizState={};
      this.startStepMode();
    },
    exitStepMode(){
      this.stepMode=false;
      this.$nextTick(()=>{ if(window.lucide) lucide.createIcons(); });
    },
    /** ガイド付き学習をやめ、単元画面に戻す（理解度の回答は保持） */
    finishStepMode(){
      this.stepMode=false;
      this.$nextTick(()=>{
        if(window.lucide) lucide.createIcons();
        const el=document.getElementById('comprehension-quiz');
        if(el) el.scrollIntoView({behavior:'smooth',block:'start'});
      });
    },
    scrollToComprehension(){
      this.$nextTick(()=>{
        const el=document.getElementById('comprehension-quiz');
        if(el) el.scrollIntoView({behavior:'smooth',block:'start'});
        if(window.lucide) lucide.createIcons();
      });
    },
    /** ヘッダ「戻る」: 同一ステップ内なら1枚前、先頭なら3ステップを終了 */
    stepGoBack(){
      if(!this.stepMode) return;
      if(this.stepStep===1){
        if(this.stepKpIdx>0){
          this.stepKpIdx--;
          this.resetFlashRevealState();
        } else {
          this.exitStepMode();
        }
      } else if(this.stepStep===2){
        if(this.stepDrillIdx>0){
          this.stepDrillIdx--;
          this.stepDrillAnswered=false;
          this.stepDrillSelected=-1;
        } else {
          const kps=this.currentUnit?.keypoints||[];
          this.stepStep=1;
          this.stepKpIdx=Math.max(0,kps.length-1);
          this.resetFlashRevealState();
        }
      } else if(this.stepStep===3){
        this.quizState={};
        const drills=this.unitDrills;
        if(drills.length>0){
          this.stepStep=2;
          this.stepDrillIdx=drills.length-1;
          this.stepDrillAnswered=false;
          this.stepDrillSelected=-1;
        } else {
          const kps=this.currentUnit?.keypoints||[];
          this.stepStep=1;
          this.stepKpIdx=Math.max(0,kps.length-1);
          this.resetFlashRevealState();
        }
      }
      this.$nextTick(()=>{
        if(window.lucide) lucide.createIcons();
        const m=document.getElementById('main');
        if(m) m.scrollTo({top:0,behavior:'smooth'});
      });
    },
    stepPipCls(n){
      if(this.stepStep===n) return 's-active';
      if(this.stepStep>n) return 's-done';
      return '';
    },
    _kpDelimiterIndex(kp){
      if(!kp||typeof kp!=='string') return -1;
      const ja=kp.indexOf('：');
      if(ja>=0) return ja;
      let depth=0;
      for(let i=0;i<kp.length;i++){
        const ch=kp[i];
        if(ch==='<') depth++;
        else if(ch==='>') depth=Math.max(0,depth-1);
        else if(ch===':'&&depth===0) return i;
      }
      return -1;
    },
    keypointHasFlip(idx){
      const kp=(this.currentUnit?.keypoints||[])[idx];
      const i=this._kpDelimiterIndex(kp);
      return i>0;
    },
    keypointTerm(idx){
      const kp=(this.currentUnit?.keypoints||[])[idx];
      const i=this._kpDelimiterIndex(kp);
      return i>0 ? kp.slice(0,i).trim() : '';
    },
    resetFlashRevealState(){
      this.stepFlashRevealed=!this.keypointHasFlip(this.stepKpIdx);
    },
    advanceStep1Card(){
      if(this.stepStep!==1) return;
      if(this.keypointHasFlip(this.stepKpIdx)&&!this.stepFlashRevealed){
        this.stepFlashRevealed=true;
        return;
      }
      this.nextStepFlash();
    },
    nextStepFlash(){
      const kps=this.currentUnit?.keypoints||[];
      if(this.stepKpIdx<kps.length-1){
        this.stepKpIdx++;
        this.resetFlashRevealState();
      } else {
        // All keypoints done — go to step 2 (or 3 if no drills)
        const drills=DRILLS[this.currentUnit?.id]||[];
        this.stepStep=drills.length>0 ? 2 : 3;
        this.stepDrillIdx=0;
        this.stepDrillAnswered=false;
        this.stepDrillSelected=-1;
        if(this.stepStep===3){
          this.$nextTick(()=>{
            const m=document.getElementById('main');
            if(m) m.scrollTo({top:m.scrollHeight,behavior:'smooth'});
          });
        }
        this.$nextTick(()=>{ if(window.lucide) lucide.createIcons(); });
      }
    },
    get unitDrills(){
      return DRILLS[this.currentUnit?.id]||[];
    },
    get unitVizHtml(){
      const c=this.currentUnit?.concept||'';
      if(!c) return '';
      const d=document.createElement('div');
      d.innerHTML=sanitizeTrustedHtml(c);
      const v=d.querySelector('.viz-taccount');
      return v?v.outerHTML:'';
    },
    doStepDrill(ci){
      if(this.stepDrillAnswered) return;
      this.stepDrillSelected=ci;
      this.stepDrillAnswered=true;
    },
    nextStepDrill(){
      const drills=this.unitDrills;
      if(this.stepDrillIdx<drills.length-1){
        this.stepDrillIdx++;
        this.stepDrillAnswered=false;
        this.stepDrillSelected=-1;
      } else {
        // All drills done — go to step 3
        this.stepStep=3;
        this.$nextTick(()=>{
          if(window.lucide) lucide.createIcons();
          const m=document.getElementById('main');
          if(m) m.scrollTo({top:m.scrollHeight,behavior:'smooth'});
        });
      }
    }
  }));
});