/* ===========================================================
   temporal-graph-canva.js
   =========================================================== */
   import './temporal-graph-timestep.js';

   class TemporalGraphCanva extends HTMLElement {
       constructor() {
           super();
           this._knowledge_graph = [];
           this._maxTimestep     = 0;
           this._cursorIndex     = -1;
           this._keyHandler      = this._keyHandler.bind(this);
       }
   
       /* ---------- observed attributes ---------- */
       static get observedAttributes() { return ['current-timestep','view-mode']; }
       get currentTimestep() { return parseInt(this.getAttribute('current-timestep') || '0'); }
       set currentTimestep(v){ this.setAttribute('current-timestep', v); this._cursorIndex=-1; }
       get viewMode()        { return this.getAttribute('view-mode') || 'single'; }
       set viewMode(v)       { this.setAttribute('view-mode', v); this._cursorIndex=-1; }
   
       /* ---------- lifecycle ---------- */
       connectedCallback()   { document.addEventListener('keydown', this._keyHandler); }
       disconnectedCallback(){ document.removeEventListener('keydown', this._keyHandler); }
       async attributeChangedCallback(n,o,v){ if(o!==v) await this._render(); }
       async render(kg){ 
           this._knowledge_graph=kg;
           if (!kg || kg.length === 0) {
               this._maxTimestep = 0;
           } else {
               this._maxTimestep=Math.max(...kg.map(r=>r[3]));
           }
           await this._render(); 
       }
   
       /* ---------- keyboard ---------- */
       _keyHandler(e){
           const k=e.key.toLowerCase();
           if(this.viewMode==='single' && (k==='q'||k==='e')){
               const total=this._relationCount();
               if(total){
                   if(k==='e'){ this._cursorIndex++; if(this._cursorIndex>total-1) this._cursorIndex=-1; }
                   else      { this._cursorIndex--; if(this._cursorIndex< -1)     this._cursorIndex=total-1; }
                   this._render();
               }
               return;
           }
           if(this.viewMode==='single'){
               if(k==='arrowleft'||k==='a') this._navigate(-1);
               else if(k==='arrowright'||k==='d') this._navigate(1);
               else if(k==='s') this.currentTimestep=this._maxTimestep+1;
           }
           if(k==='f') this._toggleView();
       }
   
       /* ---------- helpers ---------- */
       _relationCount(){
           const t=this.currentTimestep;
           if(t===this._maxTimestep+1){
               return new Set(this._knowledge_graph.map(([s,r,t])=>`${s}|${r}|${t}`)).size;
           }
           if(t<0 || t>this._maxTimestep) return 0;
           return new Set(
               this._knowledge_graph.filter(r=>r[3]===t).map(([s,r,t])=>`${s}|${r}|${t}`)
           ).size;
       }
   
       /* ---------- render ---------- */
       async _render(){
           this.innerHTML='';
   
           const wrapper=document.createElement('div');
           wrapper.className='h-full flex flex-col bg-white rounded-lg shadow-lg p-4 flex-grow overflow-hidden';
   
           const container=document.createElement('div');
           container.className=this.viewMode==='single'
               ? 'flex justify-center items-center w-full h-full'
               : 'grid grid-cols-1 md:grid-cols-2 gap-0 w-full h-full overflow-auto';
   
           if (!this._knowledge_graph || this._knowledge_graph.length === 0) {
               container.innerHTML = `<div class="flex items-center justify-center h-full text-gray-500">Paste TSV data and click Visualize.</div>`;
           } else {
               /* each real timestep */
               for(let ts=0;ts<=this._maxTimestep;ts++){
                   const el=document.createElement('temporal-graph-timestep');
                   el.data={
                       knowledge_graph:this._knowledge_graph,
                       timestep:ts,
                       cursorIndex:(this.viewMode==='single' && ts===this.currentTimestep) ? this._cursorIndex : -1
                   };
                   if(this.viewMode==='single') el.style.display = ts===this.currentTimestep ? 'flex':'none';
                   container.appendChild(el);
               }
       
               /* summary page */
               const summary=document.createElement('temporal-graph-timestep');
               summary.data={
                   knowledge_graph:this._knowledge_graph,
                   timestep:'summary',
                   cursorIndex:(this.viewMode==='single' && this.currentTimestep===this._maxTimestep+1)
                                ? this._cursorIndex : -1
               };
               if(this.viewMode==='single')
                   summary.style.display = this.currentTimestep===this._maxTimestep+1 ? 'flex':'none';
               container.appendChild(summary);
           }
   
           wrapper.appendChild(container);
           this.appendChild(wrapper);
           this.appendChild(this._buildNav());
           this._updateNavState();
   
           /* run Mermaid only on visible diagrams */
           try {
               const sel='.mermaid:not([style*="display: none"])';
               if(this.querySelector(sel)) await window.mermaid.run({querySelector:sel});
           } catch(err) { console.warn('Mermaid render warning:', err); }
       }
   
       /* ---------- navigation bar ---------- */
       _buildNav(){
           const nav=document.createElement('div');
           nav.className='bg-white shadow-lg p-4 flex flex-wrap justify-center items-center space-x-4';
   
           const mkBtn=(txt,fn)=>{
               const b=document.createElement('button'); b.textContent=txt;
               b.className='px-4 py-2 bg-[#8590F8] text-white rounded hover:bg-[#7E7E7E] transition-colors disabled:opacity-50 disabled:cursor-not-allowed';
               b.addEventListener('click',fn); return b;
           };
   
           const prev = mkBtn('Previous', ()=>this._navigate(-1));
           const next = mkBtn('Next',     ()=>this._navigate( 1));
           const toggle=mkBtn(this.viewMode==='single'?'View All':'View Single', ()=>this._toggleView());
           const dl   = mkBtn('Download SVG', ()=>this._downloadSVG());
   
           const indicators=document.createElement('div');
           indicators.className='flex flex-wrap justify-center space-x-2 my-2';
           for(let i=0;i<=this._maxTimestep+1;i++){
               const b=document.createElement('button');
               b.textContent=i===this._maxTimestep+1?'S':i+1;
               b.className='w-8 h-8 rounded-full bg-[#C5C5C5] text-[#1A1A1A] flex items-center justify-center font-bold hover:bg-[#7E7E7E] hover:text-white transition-colors m-1';
               b.addEventListener('click',()=>{this.currentTimestep=i;});
               indicators.appendChild(b);
           }
   
           nav.append(prev,indicators,next,toggle,dl);
           this._prevB=prev; this._nextB=next; this._toggleB=toggle; this._indWrap=indicators;
           return nav;
       }
   
       _navigate(dx){
           const total=this._maxTimestep+2;
           let n=this.currentTimestep+dx;
           if(n<0) n=0; if(n>=total) n=total-1;
           this.currentTimestep=n;
       }
   
       _toggleView(){
           this.viewMode = this.viewMode==='single' ? 'all' : 'single';
           this._toggleB.textContent = this.viewMode==='single' ? 'View All' : 'View Single';
       }
   
       _updateNavState(){
           const total=this._maxTimestep+2;
           const noData = !this._knowledge_graph || this._knowledge_graph.length === 0;
   
           if(this.viewMode==='all' || noData){
               this._prevB.disabled=this._nextB.disabled=true;
               if(this._indWrap) this._indWrap.querySelectorAll('button').forEach(b=>b.disabled=true);
           } else {
               this._prevB.disabled = this.currentTimestep===0;
               this._nextB.disabled = this.currentTimestep===total-1;
               if (this._indWrap) this._indWrap.querySelectorAll('button').forEach((b,i)=>{
                   b.disabled=false;
                   if(i===this.currentTimestep){
                       b.classList.replace('bg-[#C5C5C5]','bg-[#8590F8]');
                       b.classList.replace('text-[#1A1A1A]','text-white');
                   } else {
                       b.classList.replace('bg-[#8590F8]','bg-[#C5C5C5]');
                       b.classList.replace('text-white','text-[#1A1A1A]');
                   }
               });
           }
       }
   
       /* ---------- download SVG ---------- */
       async _downloadSVG(){
           let svg;
           if(this.viewMode==='single'){
               svg=this.querySelector('.mermaid:not([style*="display: none"]) svg');
           } else {
               const svgs=[...this.querySelectorAll('.mermaid svg')];
               const combo=document.createElementNS('http://www.w3.org/2000/svg','svg');
               let y=0;
               svgs.forEach(s=>{
                   const g=document.createElementNS('http://www.w3.org/2000/svg','g');
                   g.innerHTML=s.innerHTML;
                   g.setAttribute('transform',`translate(0,${y})`);
                   combo.appendChild(g);
                   y+=parseInt(s.getAttribute('height'))+20||20;
               });
               combo.setAttribute('width',Math.max(...svgs.map(s=>parseInt(s.getAttribute('width'))||0)));
               combo.setAttribute('height',y);
               svg=combo;
           }
           if(!svg) return console.error('downloadSVG: no SVG element');
           const xml=new XMLSerializer().serializeToString(svg);
           const src=/^<svg[^>]+xmlns=/.test(xml)?xml:xml.replace(/^<svg/,'<svg xmlns="http://www.w3.org/2000/svg"');
           const url='data:image/svg+xml;charset=utf-8,' + encodeURIComponent('<?xml version="1.0"?>\n'+src);
           const a=document.createElement('a'); a.href=url; a.download='temporal_graph.svg';
           document.body.appendChild(a); a.click(); document.body.removeChild(a);
       }
   }
   
   customElements.define('temporal-graph-canva', TemporalGraphCanva);

/* All rights reserved Michael Anthony 2025 */