// An opt-in, bounded browser recording for human review. It never owns capture
// tracks or a network client; stopping it must not stop the numeric observer.
export class LocalRecording {
    constructor({Recorder=globalThis.MediaRecorder,onStatus=()=>{},onReady=()=>{},
        maxBytes=128*1024*1024,maxMs=180000}={}) {
        Object.assign(this,{Recorder,onStatus,onReady,maxBytes,maxMs});
        this.serial=0;this.active=null;
    }
    get supported() {return typeof this.Recorder==='function';}
    start(stream) {
        this.discard();
        if(!this.supported){this.onStatus('Recording unavailable in this browser.');return false;}
        const serial=this.serial;
        const mimeType=['video/webm;codecs=vp8,opus','video/webm','video/mp4'].find(
            type=>this.Recorder.isTypeSupported(type));
        try {
            const recorder=new this.Recorder(stream,{...(mimeType?{mimeType}:{}),
                videoBitsPerSecond:4000000,audioBitsPerSecond:128000});
            const run={recorder,chunks:[],bytes:0,failed:false};
            this.active=run;
            recorder.ondataavailable=({data})=>{
                if(serial!==this.serial||run.failed||!data.size)return;
                if(run.bytes+data.size>this.maxBytes) {
                    // A truncated container may not be playable: fail explicitly,
                    // clear it, and leave measurement running rather than claim success.
                    run.failed=true;run.chunks=[];
                    this.onStatus('Recording exceeded its memory limit; no clip saved.');
                    this.finish();return;
                }
                run.chunks.push(data);run.bytes+=data.size;
            };
            recorder.onerror=()=>{
                if(serial!==this.serial)return;
                run.failed=true;run.chunks=[];
                this.onStatus('Recording failed; numeric measurement continues.');
                this.finish();
            };
            recorder.onstop=()=>{
                clearTimeout(run.timer);clearTimeout(run.deadline);
                if(serial!==this.serial)return;
                this.active=null;
                if(!run.failed&&run.bytes) {
                    const blob=new Blob(run.chunks,{type:recorder.mimeType||mimeType||'video/webm'});
                    this.onReady(blob);
                    this.onStatus('Ready for local replay · nothing uploaded');
                } else if(!run.failed)this.onStatus('No recording data was produced.');
                run.chunks=[];
            };
            recorder.start(1000);
            run.timer=setTimeout(()=>this.finish(),this.maxMs);
            this.onStatus('Recording locally · nothing uploaded');
            return true;
        } catch {
            this.discard();this.onStatus('Recording could not start; numeric measurement continues.');
            return false;
        }
    }
    finish() {
        const run=this.active;
        if(!run||run.finishing)return;
        run.finishing=true;clearTimeout(run.timer);
        if(!run.failed)this.onStatus('Preparing local replay…');
        run.deadline=setTimeout(()=>{
            if(this.active!==run)return;
            this.discard();this.onStatus('Recording could not finalize; no clip saved.');
        },10000);
        try {if(run.recorder.state!=='inactive')run.recorder.stop();}
        catch {this.discard();this.onStatus('Recording could not finalize; no clip saved.');}
    }
    discard() {
        this.serial++;
        const run=this.active;this.active=null;
        if(!run)return;
        clearTimeout(run.timer);clearTimeout(run.deadline);run.chunks=[];
        run.recorder.ondataavailable=null;run.recorder.onstop=null;run.recorder.onerror=null;
        try {if(run.recorder.state!=='inactive')run.recorder.stop();}catch {}
    }
}