import test from 'node:test';
import assert from 'node:assert/strict';

const module = await import('../../web/js/workspace/viewer-state.mjs').catch(error => {
    if (error.code !== 'ERR_MODULE_NOT_FOUND') throw error;
    return {};
});
function session(options) {
    assert.equal(typeof module.createViewerSession, 'function', 'viewer session contract is exported');
    return module.createViewerSession(options);
}
const entries = () => Array.from({length: 161}, (_, index) => ({root_index: index % 2,
    path: `folder/${index}.png`, filename: `${index}.png`, root_scope: 'a'.repeat(64),
    thumbnail_url: `/prompt_manager/images/serve/thumbnails/${index}.png?root=${index % 2}&v=17&root_scope=${'a'.repeat(64)}`,
    url: `/prompt_manager/images/serve/folder/${index}.png?root=${index % 2}&root_scope=${'a'.repeat(64)}`}));

test('viewer freezes loaded identities and wraps across unmounted entries', () => {
    const items = entries(), updates = [];
    const view = session({items, initialKey: '0:folder/0.png', onChange: (state, entry) => updates.push({state, entry})});
    items[160].url = '/wrong-root'; items[160].thumbnail_url = '/wrong-version?v=18';items[160].root_scope = 'b'.repeat(64); items.reverse(); items.push(items[0]);
    view.navigate(-1);
    assert.deepEqual(view.state, {key:'0:folder/160.png',index:160,total:161,phase:'stopped',requested:false,mediaReady:false});
    assert.equal(updates.at(-1).entry.url, `/prompt_manager/images/serve/folder/160.png?root=0&root_scope=${'a'.repeat(64)}`);
    assert.equal(updates.at(-1).entry.root_scope, 'a'.repeat(64));
    assert.equal(updates.at(-1).entry.thumbnail_url, `/prompt_manager/images/serve/thumbnails/160.png?root=0&v=17&root_scope=${'a'.repeat(64)}`);
    assert.ok(Object.isFrozen(updates.at(-1).entry)); assert.ok(Object.isFrozen(view.state));
    view.navigate(1); assert.equal(view.state.key, '0:folder/0.png');
    view.navigate(1); assert.equal(view.state.key, '1:folder/1.png');
    view.dispose();
});

test('viewer rejects empty duplicate or unknown identity', () => {
    for (const [items, initialKey] of [[[], '0:a.png'], [[{path:'a.png'}], 'undefined:a.png'],
        [[{root_index:0,path:''}], '0:'], [[{root_index:0,path:'a.png'},{root_index:0,path:'a.png'}], '0:a.png'],
        [entries(), '0:missing.png']]) assert.throws(() => session({items,initialKey}), TypeError);
    const view = session({items:entries(),initialKey:'0:folder/0.png'});
    for (const direction of [0,2,-2,'1',null]) assert.throws(() => view.navigate(direction), TypeError);
    assert.equal(view.state.index, 0); view.dispose();
});

test('viewer ignores stale readiness after navigation and disposal', () => {
    let calls = 0;
    const view = session({items:entries(),initialKey:'0:folder/0.png',onChange:() => calls++,
        setTimer:() => assert.fail('Task4 must not start a timer'),clearTimer:() => assert.fail('No timer exists')});
    view.ready('0:folder/0.png'); assert.equal(view.state.mediaReady,true);
    view.navigate(1); view.failed('0:folder/0.png'); view.ready('0:folder/0.png');
    assert.equal(view.state.mediaReady,false); assert.equal(view.state.phase,'stopped');
    view.failed('1:folder/1.png'); assert.equal(view.state.phase,'error');
    view.ready('1:folder/1.png'); assert.equal(view.state.phase,'stopped');
    view.dispose(); const after = calls;
    view.ready('1:folder/1.png'); view.failed('1:folder/1.png'); view.navigate(1); view.dispose();
    assert.equal(calls,after); assert.equal(view.state.phase,'disposed'); assert.equal(view.state.requested,false);
});

function timedSession(items = entries().slice(0,3)) {
    let now = 0, serial = 0;
    const pending = new Map(), callbacks = [];
    const view = session({items,initialKey:`${items[0].root_index}:${items[0].path}`,
        setTimer: (callback, delay) => {const id=++serial;pending.set(id,{at:now+delay,callback});callbacks.push(callback);return id;},
        clearTimer: id => pending.delete(id)});
    const tick = ms => {now+=ms;for(const [id,timer] of [...pending])if(timer.at<=now){pending.delete(id);timer.callback();}};
    return {view,pending,callbacks,tick};
}

test('slideshow schedules once only after current image ready', () => {
    const {view,pending,tick}=timedSession();
    view.play?.();assert.equal(view.state.phase,'waiting-image');assert.equal(view.state.requested,true);assert.equal(pending.size,0);
    view.ready(view.state.key);assert.equal(view.state.phase,'playing-image');assert.equal(pending.size,1);
    view.ready(view.state.key);view.play();assert.equal(pending.size,1);
    tick(3499);assert.equal(view.state.index,0);tick(1);assert.equal(view.state.index,1);
    assert.equal(view.state.phase,'waiting-image');assert.equal(pending.size,0);
    view.ready(view.state.key);assert.equal(pending.size,1);view.dispose();assert.equal(pending.size,0);
});

test('slideshow pauses at video and resumes retained intent only after manual image navigation', () => {
    const items=entries().slice(0,3);items[1].is_video=true;
    const {view,pending,tick}=timedSession(items);
    view.ready(view.state.key);view.play?.();tick(3500);
    assert.equal(view.state.index,1);assert.equal(view.state.phase,'paused-video');assert.equal(view.state.requested,true);assert.equal(pending.size,0);
    view.ready(view.state.key);tick(7000);assert.equal(view.state.index,1);assert.equal(view.state.phase,'paused-video');
    view.navigate(1);assert.equal(view.state.phase,'waiting-image');view.ready(view.state.key);assert.equal(view.state.phase,'playing-image');
    view.navigate(-1);view.stop();view.ready(view.state.key);view.navigate(1);view.ready(view.state.key);
    assert.equal(view.state.phase,'stopped');assert.equal(pending.size,0);view.dispose();
});

test('stop cancels waiting and paused intent despite late callbacks', () => {
    const {view,pending,callbacks}=timedSession();view.play?.();view.stop?.();view.ready(view.state.key);
    assert.equal(view.state.requested,false);assert.equal(pending.size,0);
    view.play?.();assert.equal(pending.size,1);const late=callbacks.at(-1);
    view.stop();late();view.ready(view.state.key);assert.equal(view.state.index,0);assert.equal(view.state.phase,'stopped');
    view.play();view.navigate(1);late();assert.equal(view.state.index,1);assert.equal(view.state.phase,'waiting-image');
    view.ready(view.state.key);assert.equal(pending.size,1);view.dispose();
});

test('hidden interaction error and disposal never resume', () => {
    const {view,pending,callbacks}=timedSession();view.ready(view.state.key);view.play?.();
    assert.equal(pending.size,1);view.stop();for(const callback of callbacks)callback();view.ready(view.state.key);
    assert.equal(view.state.phase,'stopped');view.play();view.failed(view.state.key);view.ready(view.state.key);
    assert.equal(view.state.phase,'stopped');assert.equal(view.state.requested,false);assert.equal(pending.size,0);
    view.play();view.dispose();const disposed=view.state;
    for(const callback of callbacks)callback();view.play();view.stop();view.ready(view.state.key);view.failed(view.state.key);view.navigate(1);view.dispose();
    assert.equal(view.state,disposed);assert.equal(pending.size,0);
});

test('slideshow cannot start on video one entry or media error', () => {
    for(const items of [[entries()[0]],[{...entries()[0],is_video:true},entries()[1]]]) {
        const {view,pending}=timedSession(items);view.play?.();assert.equal(view.state.requested,false);assert.equal(pending.size,0);view.dispose();
    }
    const {view,pending}=timedSession();view.failed(view.state.key);view.play?.();assert.equal(view.state.phase,'error');assert.equal(pending.size,0);view.dispose();
});

test('explicit occurrence session retains video pause and timer invalidation with location keys',async()=>{
    const history=await import('../../web/js/workspace/history-media.mjs');
    const run='22222222-2222-2222-2222-222222222222',epoch='11111111-1111-1111-1111-111111111111',scope='a'.repeat(64);
    const items=['c','d'].map((key,index)=>{const query=new URLSearchParams({node:String(index),ordinal:'0',epoch,current_scope:scope}),base=`/prompt_manager/history/runs/${run}/output/current`;return {kind:'reported-location',occurrence:{run_id:run,output_node_id:String(index),image_ordinal:0},reference:{folder_type:'output',subfolder:'',filename:'a.png',path_style:'posix',root_key:'b'.repeat(64)},history_epoch:epoch,current_scope:scope,location_key:key.repeat(64),filename:'a.png',is_video:index===1,url:`${base}/media?${query}`,thumbnail_url:`${base}/thumbnail?${query}`,inspection_url:`${base}/inspection?${query}`};});
    const timers=[],pending=new Set();let callbacks=0;
    const view=session({adapter:history.reportedLocationAdapter,items,initialKey:'c'.repeat(64),onChange:()=>callbacks++,setTimer:fn=>{timers.push(fn);pending.add(fn);return fn;},clearTimer:fn=>pending.delete(fn)});
    view.play();view.ready('c'.repeat(64));assert.equal(pending.size,1);timers[0]();assert.equal(view.state.key,'d'.repeat(64));assert.equal(view.state.phase,'paused-video');view.stop();view.navigate(-1);view.ready('c'.repeat(64));assert.equal(view.state.requested,false);view.dispose();const count=callbacks;timers[0]();view.ready('d'.repeat(64));assert.equal(callbacks,count);
});