import {VideoMetrics,receipt} from './metrics.js';
import {RunReporter} from './reporting.js';
import {PairedObserver} from './paired-observer.js';
import {reviewControls} from './review-controls.js';
import {releaseCapture,stopTracks} from './capture-lifecycle.js';
import {ContinuityWatch,WATCH_MS} from './continuity-watch.js';
const el=id=>document.getElementById(id);
const review=reviewControls(document);
let generation=0, current=null, last=null, reportingRun=null;
function modeControls() {
    const watch=el('observation-mode').value==='watch';
    el('paired-signal').disabled=watch||current!==null;
    review.lock(watch||current!==null);
    el('watch-help').hidden=!watch;
    el('start').textContent=watch?'Start 10-hour watch':'Start 2-minute check';
}
el('observation-mode').onchange=()=>{
    if(current)return;
    if(el('observation-mode').value==='watch') {
        el('paired-signal').checked=false;el('record-review').checked=false;review.discard();
    }
    modeControls();
};
function release(run) {
    releaseCapture(run,el('preview'),()=>review.finish());
}
function update(run) {
    if(current!==run)return;
    const sample=receipt(run.video,run.audio,run.settings,performance.now()-run.started,'observing');
    if(run.paired)sample.paired=run.paired.summary();
    if(run.watch) {
        run.watch.observe(sample,run.audioReceivedAt);
        sample.watch=run.watch.summary();
    }
    el('metrics').textContent=JSON.stringify(sample,null,2);
    if(run.observing)run.reporter.observe(sample);
}
function stop(reason='operator') {
    generation++;
    const run=current; current=null;
    if(run) {
        release(run);
        last=receipt(run.video,run.audio,run.settings,performance.now()-run.started,reason);
        if(run.paired)last.paired=run.paired.summary();
        if(run.watch) {
            run.watch.observe(last,run.audioReceivedAt);run.watch.finish(reason);
            last.watch=run.watch.summary(true);
        }
        run.reporter.finish(last);
        const display=run.watch?{...last,watch:run.watch.summary()}:last;
        el('metrics').textContent=JSON.stringify(display,null,2);
        el('export').disabled=false;
    }
    el('preview').srcObject=null;
    el('start').disabled=!el('audio-device').value || !el('video-device').value;
    el('stop').disabled=true; el('devices').disabled=false;
    el('observation-mode').disabled=false;modeControls();
    el('status').textContent=`Stopped · ${reason}`;
}
el('devices').onclick=async()=>{
    stop('selecting devices');
    const ticket=++generation;
    el('devices').disabled=true; el('start').disabled=true; el('stop').disabled=false;
    el('status').textContent='Requesting device permission…';
    const timer=setTimeout(()=>{if(generation===ticket)stop('permission timeout');},20000);
    try {
        const stream=await navigator.mediaDevices.getUserMedia({audio:true,video:true});
        stopTracks(stream);
        if(generation!==ticket)return;
        const devices=await navigator.mediaDevices.enumerateDevices();
        if(generation!==ticket)return;
        for(const [id,kind] of [['video-device','videoinput'],['audio-device','audioinput']]) {
            const select=el(id), saved=select.value;
            select.replaceChildren(new Option('Select a device',''));
            for(const d of devices.filter(d=>d.kind===kind)) select.add(new Option(d.label||'Unnamed device',d.deviceId));
            select.value=saved;
        }
        el('status').textContent='Select a camera and microphone, then Start.';
        el('devices').disabled=false; el('stop').disabled=true;
    } catch { if(generation===ticket)stop('device permission unavailable'); }
    finally {clearTimeout(timer);}
};
for(const id of ['audio-device','video-device']) el(id).onchange=()=>{
    if(current)stop('device selection changed');
    el('start').disabled=!el('audio-device').value||!el('video-device').value;
};
el('start').onclick=async()=>{
    if(current || !el('audio-device').value || !el('video-device').value)return;
    if(!el('preview').requestVideoFrameCallback || !window.AudioWorkletNode) {
        el('status').textContent='This browser lacks the required observation APIs.';return;
    }
    const ticket=++generation;
    const watchEnabled=el('observation-mode').value==='watch';
    const run={started:performance.now(),video:new VideoMetrics(),audio:null,audioReceivedAt:null,
        settings:{},watchEnabled,pairedEnabled:!watchEnabled&&el('paired-signal').checked};
    current=run; last=null;
    reportingRun=run;
    run.reporter=watchEnabled?{
        observe(){},finish(){if(reportingRun===run)el('report-status').textContent='Local watch · Save metrics before closing';},
    }:new RunReporter(message=>{
        if(reportingRun===run)el('report-status').textContent=message;
    });
    if(watchEnabled){review.discard();el('report-status').textContent='Local watch · metrics are not uploaded';}
    el('start').disabled=true; el('devices').disabled=true; el('stop').disabled=false; el('export').disabled=true;
    el('paired-signal').disabled=true;
    el('observation-mode').disabled=true;
    review.lock(true);
    el('status').textContent='Starting…';
    run.setupTimer=setTimeout(()=>{if(current===run)stop('setup timeout');},20000);
    try {
        const stream=await navigator.mediaDevices.getUserMedia({
            video:{deviceId:{exact:el('video-device').value}},
            audio:{deviceId:{exact:el('audio-device').value},echoCancellation:false,noiseSuppression:false,autoGainControl:false},
        });
        if(generation!==ticket){stopTracks(stream);return;}
        run.stream=stream;
        for(const track of stream.getTracks())track.onended=()=>{if(current===run)stop('device ended');};
        const vs=stream.getVideoTracks()[0].getSettings(),as=stream.getAudioTracks()[0].getSettings();
        run.settings={video:{width:vs.width,height:vs.height,frameRate:vs.frameRate},
            audio:{sampleRate:as.sampleRate,channelCount:as.channelCount,echoCancellation:as.echoCancellation,
                noiseSuppression:as.noiseSuppression,autoGainControl:as.autoGainControl}};
        run.context=new AudioContext();
        await run.context.audioWorklet.addModule(run.pairedEnabled?'paired-worklet.js':'activity-worklet.js');
        if(generation!==ticket)return;
        if(run.pairedEnabled)run.paired=new PairedObserver(run.context,el('preview'));
        run.node=new AudioWorkletNode(run.context,run.pairedEnabled?'av-paired-signals':'av-activity',
            {processorOptions:{continuityWatch:watchEnabled}});
        run.node.onprocessorerror=()=>{if(current===run)stop('audio observer error');};
        run.node.port.onmessage=({data})=>{
            if(current!==run)return;
            if(watchEnabled&&data.watchStopped===true){stop('audio observer deadline or lost owner');return;}
            run.audioReceivedAt=performance.now();
            if(run.paired){run.audio=data.activity;run.paired.audioMessage(data);}else run.audio=data;
            run.node.port.postMessage('ack');
            if(run.observing&&run.paired&&!run.signalStarted) {
                const paired=run.paired.summary();
                if(paired.continuity.frames>=2&&paired.pilot?.windows>0) {
                    run.signalStarted=true;clearTimeout(run.signalTimer);
                    run.started=performance.now();run.video=new VideoMetrics();
                    run.timer=setTimeout(()=>{if(current===run)stop('120 seconds complete');},120000);
                    el('status').textContent='Measuring known A/V signals · 120 seconds';
                }
            }
            update(run);
        };
        run.source=run.context.createMediaStreamSource(new MediaStream(stream.getAudioTracks()));
        run.source.connect(run.node);run.node.connect(run.context.destination);
        await run.context.resume();
        if(generation!==ticket)return;
        if(run.context.state!=='running')throw new Error('audio context did not start');
        el('preview').srcObject=stream;
        await el('preview').play();
        if(generation!==ticket)return;
        clearTimeout(run.setupTimer);
        run.started=performance.now();
        if(watchEnabled)run.watch=new ContinuityWatch();
        run.observing=true;
        // Reporting and freshness cannot depend on the audio path still working.
        run.updateTimer=setInterval(()=>update(run),1000);
        run.recording=watchEnabled?false:review.begin(stream);
        function frame(now,metadata) {
            if(current!==run)return;
            try {
                run.video.observe(metadata.expectedDisplayTime,metadata.presentedFrames);
                run.paired?.frame(metadata.expectedDisplayTime);
                run.callback=el('preview').requestVideoFrameCallback(frame);
            } catch {if(current===run)stop('video observer error');}
        }
        run.callback=el('preview').requestVideoFrameCallback(frame);
        if(watchEnabled) {
            run.timer=setTimeout(()=>{if(current===run)stop('10 hours observed');},WATCH_MS);
            el('status').textContent='Watching continuity · 10-hour limit · local metrics only';
        } else if(run.paired) {
            run.signalTimer=setTimeout(()=>{if(current===run)stop('test signal timeout');},60000);
            el('status').textContent='Waiting for known A/V signals · start the source now';
        } else {
            run.timer=setTimeout(()=>{if(current===run)stop('120 seconds complete');},120000);
            el('status').textContent=run.recording?'Observing both devices · recording locally':'Observing both devices · no recording';
        }
    } catch { if(current===run)stop('capture/setup failed'); }
    finally { if(current!==run)release(run); }
};
el('stop').onclick=()=>stop();
el('export').onclick=()=>{
    if(!last)return;
    const url=URL.createObjectURL(new Blob([JSON.stringify(last,null,2)],{type:'application/json'}));
    const link=document.createElement('a');link.href=url;
    link.download=last.watch?'av-continuity-watch.json':'av-test-metrics.json';link.click();
    setTimeout(()=>URL.revokeObjectURL(url),1000);
};
window.addEventListener('pagehide',()=>{stop('page closed');review.discard();});
document.addEventListener('visibilitychange',()=>{if(document.hidden&&current)stop('page hidden; timing invalid');});