'use strict';
let playbackRange=null;
function localDateTime(value){const d=new Date(value);return `${d.getFullYear()}-${String(d.getMonth()+1).padStart(2,'0')}-${String(d.getDate()).padStart(2,'0')}T${d.toTimeString().slice(0,8)}`;}
function resetPlayback(){
  playbackGeneration++;playbackRange=null;const v=$('#play-video');v.pause();v.removeAttribute('src');v.load();
  $('#play-empty').hidden=false;$('#download').hidden=true;$('#clip-download').hidden=true;$('#clip-status').textContent='';$('#clip-form').reset();
  spans=[];queryCamera='';queryStart=null;queryEnd=null;$('#play-info').textContent='选择日期，查看实际录像时段';$('#play-position').textContent='';drawTimeline();$('#recording-list').innerHTML='';
}
async function queryRecordings(){
  resetPlayback();const generation=playbackGeneration,id=$('#play-camera').value,date=$('#play-date').value;
  if(!id||!date){toast('请选择摄像头和日期');return;}
  if($('#archive-source').value==='recorder'){$('#play-info').textContent='录像机历史回放接口待接入。现有录像仍可在录像机或原厂 App 中查看。';return;}
  queryStart=new Date(date+'T00:00:00');queryEnd=new Date(queryStart);queryEnd.setDate(queryEnd.getDate()+1);queryCamera=id;
  $('#play-info').textContent='正在查找录像…';
  try{const d=await api('/api/recordings?'+new URLSearchParams({camera:id,start:queryStart.toISOString(),end:queryEnd.toISOString()}));
    if(generation!==playbackGeneration||!loggedIn)return;
    spans=RecordingRanges.normalize(d.items,queryStart,queryEnd);
    $('#play-info').textContent=spans.length?`找到 ${spans.length} 段连续录像`:'该日期暂无可回放录像';drawTimeline();
    $('#recording-list').innerHTML=spans.map(s=>`<button class="recording-item" data-span="${new Date(s.start).toISOString()}">${new Date(s.start).toLocaleTimeString()} — ${new Date(s.end).toLocaleTimeString()}<small>${((s.end-s.start)/60000).toFixed(1)} 分钟 · 点击播放</small></button>`).join('');
    if(spans.length)playAt(new Date(spans[0].start));
  }catch(e){if(!e.stale&&generation===playbackGeneration)$('#play-info').textContent=e.message;}
}
function drawTimeline(){
  const c=$('#timeline'),w=c.clientWidth;if(!w)return;const scale=window.devicePixelRatio||1;c.width=w*scale;c.height=76*scale;const ctx=c.getContext('2d');ctx.scale(scale,scale);const theme=getComputedStyle(document.documentElement);ctx.fillStyle=theme.getPropertyValue('--timeline-paper').trim()||'#ede8dd';ctx.fillRect(0,0,w,76);ctx.strokeStyle=theme.getPropertyValue('--timeline-grid').trim()||'#d3ccbc';
  for(let i=0;i<=24;i++){const x=w*i/24;ctx.beginPath();ctx.moveTo(x,0);ctx.lineTo(x,i%6===0?76:12);ctx.stroke();}
  if(!queryStart||!queryEnd)return;ctx.fillStyle=theme.getPropertyValue('--timeline-range').trim()||'#4c7761';const total=queryEnd-queryStart;
  for(const s of spans){const a=(s.start-queryStart)/total,b=(s.end-queryStart)/total;if(b>a)ctx.fillRect(a*w,25,Math.max(2,(b-a)*w),25);}
}
function playbackParams(range){return new URLSearchParams({camera:queryCamera,start:new Date(range.start).toISOString(),duration:String((range.end-range.start)/1000)});}
function playAt(date,preserveClip=false){
  const range=RecordingRanges.at(spans,date);if(!range){toast('这个时间没有录像，请选择绿色时段');return;}
  playbackRange=range;const params=playbackParams(range),v=$('#play-video');v.src='/media/playback?'+params;v.play().catch(()=>{});
  $('#play-info').textContent='回放起点 '+new Date(range.start).toLocaleString()+' · 每次最多一小时，结束后按续播选项处理';$('#play-empty').hidden=true;
  $('#download').href='/media/playback?'+params+'&download=1';$('#download').setAttribute('download','recording.mp4');$('#download').hidden=false;
  if(!preserveClip){$('#clip-start').value=localDateTime(range.start);$('#clip-end').value=localDateTime(range.end);$('#clip-download').hidden=true;$('#clip-status').textContent='可修改起止时间后生成下载链接';}
}
function continuePlayback(){
  const v=$('#play-video');if(!loggedIn||activePage!=='playback'||!playbackRange||!v.ended)return;
  if(v.currentTime+2<(playbackRange.end-playbackRange.start)/1000){$('#play-info').textContent='录像提前结束，已停止续播；请核对该片段或重新查询';return;}
  if(!$('#play-autonext').checked){$('#play-info').textContent='本段播放结束，自动续播已关闭';return;}
  const end=playbackRange.end,next=RecordingRanges.next(spans,end);
  if(!next){$('#play-info').textContent='所选日期的已查询录像播放完毕';return;}
  playAt(new Date(next.start),true);if(next.start>end)$('#play-info').textContent=`已跳过无录像时段，续播 ${new Date(next.start).toLocaleString()}`;
}
function makeClip(){
  $('#clip-download').hidden=true;
  try{if(!queryCamera)throw Error('请先查询录像');const range=RecordingRanges.clip(spans,new Date($('#clip-start').value),new Date($('#clip-end').value));
    const a=$('#clip-download');a.href='/media/playback?'+playbackParams(range)+'&download=1';a.setAttribute('download','recording.mp4');a.hidden=false;$('#clip-status').textContent=`已选 ${((range.end-range.start)/60e3).toFixed(2)} 分钟，下载保留原始编码。`;
  }catch(e){$('#clip-status').textContent=e.message;}
}
$('#query-recordings').onclick=queryRecordings;
$('#play-camera').onchange=()=>{resetPlayback();const c=state.cameras.find(c=>c.id===$('#play-camera').value);$('#archive-source').value=c?.archiveSource||'local';};$('#archive-source').onchange=resetPlayback;$('#play-date').onchange=resetPlayback;
$('#seek-button').onclick=()=>{if(!queryCamera){toast('请先查询录像');return;}playAt(new Date($('#play-date').value+'T'+$('#seek-time').value));};
$('#timeline').onclick=e=>{if(!queryStart)return;const r=e.currentTarget.getBoundingClientRect();playAt(new Date(+queryStart+(queryEnd-queryStart)*(e.clientX-r.left)/r.width));};
$('#play-video').onerror=()=>{if($('#play-video').getAttribute('src'))$('#play-info').textContent='回放失败：请稍后重试，或下载原始片段；服务器最多同时转换两个回放。';};
$('#play-video').onplaying=()=>{$('#play-empty').hidden=true;};$('#play-video').onended=continuePlayback;
$('#play-video').ontimeupdate=()=>{if(playbackRange)$('#play-position').textContent='录像时间 '+new Date(Math.min(playbackRange.end,playbackRange.start+$('#play-video').currentTime*1000)).toLocaleString();};
$('#clip-form').onsubmit=e=>{e.preventDefault();makeClip();};
for(const id of ['clip-start','clip-end'])$('#'+id).oninput=()=>{$('#clip-download').hidden=true;$('#clip-status').textContent='起止时间已修改，请重新生成链接';};
$$('[data-clip-mark]').forEach(b=>b.onclick=()=>{if(!playbackRange||!$('#play-video').videoWidth){toast('请先播放录像');return;}$('#clip-'+b.dataset.clipMark).value=localDateTime(Math.min(playbackRange.end,playbackRange.start+$('#play-video').currentTime*1000));$('#clip-download').hidden=true;$('#clip-status').textContent='已使用当前播放位置，请重新生成链接';});
$('#play-date').value=localDateTime(Date.now()).slice(0,10);window.addEventListener('resize',drawTimeline);