/**
 * WPDO User Stress Test — admin tab JS
 *
 * - 2s polling while running/benchmarking
 * - Start / Cancel / Cleanup / Re-run benchmark
 * - Renders progress + benchmark report
 *
 * @since 2.6.7
 */
( function () {
	'use strict';

	const cfg = window.wpdoStressTest;
	if ( ! cfg || ! cfg.restUrl ) {
		return;
	}
	if ( ! document.querySelector( '.wpdo-stress-test-tab' ) ) {
		return;
	}

	const $ = ( sel ) => document.querySelector( sel );
	const restUrl = cfg.restUrl.replace( /\/$/, '' );
	const headers = { 'Content-Type': 'application/json', 'X-WP-Nonce': cfg.nonce };

	let pollTimer = null;

	// ── API helpers ─────────────────────────────────────────────────────────

	async function apiCall( path, method = 'GET', body = null ) {
		const opts = { method, headers, credentials: 'same-origin' };
		if ( body ) {
			opts.body = JSON.stringify( body );
		}
		const resp = await fetch( restUrl + path, opts );
		const text = await resp.text();
		try {
			return { ok: resp.ok, status: resp.status, data: text ? JSON.parse( text ) : null };
		} catch ( e ) {
			return { ok: false, status: resp.status, data: { error: text } };
		}
	}

	// ── Rendering ───────────────────────────────────────────────────────────

	function fmt( n ) {
		if ( n === null || n === undefined ) {
			return '—';
		}
		return Number( n ).toLocaleString();
	}

	function renderProgress( state ) {
		const isRunning = state.status === 'running' || state.status === 'benchmarking';
		const card = $( '#wpdo-st-progress-card' );
		if ( card ) {
			card.style.display = ( isRunning || state.status === 'completed' || state.status === 'failed' || state.status === 'cancelled' ) ? '' : 'none';
		}
		setText( '#wpdo-st-pg-status', state.status || 'idle' );
		setText( '#wpdo-st-pg-mode', state.mode || '' );
		setText( '#wpdo-st-pg-pct', ( state.pct || 0 ) + '%' );
		setText( '#wpdo-st-pg-processed', fmt( state.processed || 0 ) );
		setText( '#wpdo-st-pg-target', fmt( state.target || 0 ) );
		setText( '#wpdo-st-pg-rate', state.rate_per_sec || 0 );
		setText( '#wpdo-st-pg-elapsed', state.elapsed_sec || 0 );
		setText( '#wpdo-st-pg-eta', state.eta_sec || 0 );
		setText( '#wpdo-st-pg-batches', state.batches_done || 0 );
		setText( '#wpdo-st-pg-mem', ( ( state.peak_memory || 0 ) / 1048576 ).toFixed( 1 ) );

		const bar = $( '#wpdo-st-pg-bar' );
		if ( bar ) {
			bar.style.width = ( state.pct || 0 ) + '%';
		}

		setText( '#wpdo-st-count', fmt( state.test_user_count || 0 ) );

		const startBtn   = $( '#wpdo-st-start' );
		const cancelBtn  = $( '#wpdo-st-cancel' );
		const cleanupBtn = $( '#wpdo-st-cleanup' );
		const benchBtn   = $( '#wpdo-st-rerun-bench' );
		if ( startBtn ) {
			startBtn.disabled = isRunning;
		}
		if ( cancelBtn ) {
			cancelBtn.disabled = ! isRunning;
		}
		if ( cleanupBtn ) {
			cleanupBtn.disabled = isRunning || ( state.test_user_count || 0 ) === 0;
		}
		if ( benchBtn ) {
			benchBtn.disabled = isRunning || ( state.test_user_count || 0 ) === 0;
		}
	}

	function renderBenchmark( bench ) {
		if ( ! bench ) {
			return;
		}
		const card = $( '#wpdo-st-bench-card' );
		const content = $( '#wpdo-st-bench-content' );
		if ( ! card || ! content ) {
			return;
		}
		card.style.display = '';

		const w = bench.write || {};
		const dbSizes = bench.db_sizes || [];
		const q = bench.query || {};

		const labels = {
			get_field_membership_level: 'WPDO_API::get_field (membership_level) ×100',
			get_entity_full: 'WPDO_API::get_entity (整筆) ×100',
			range_gold_high_points: '索引範圍：gold + points>5000',
			sort_recent_active_100: '排序：last_active_at DESC LIMIT 100',
			join_top_gold_active: 'JOIN：top gold + active LIMIT 100',
			eav_range_baseline: '原生 EAV 等價查詢（baseline）',
		};

		let html = '';
		// Write metrics
		html += '<h4 style="margin-bottom:6px;">▍ 寫入指標</h4>';
		html += '<table class="widefat" style="margin-bottom:14px;"><tbody>';
		html += `<tr><td>模式</td><td><code>${ esc( w.mode ) }</code></td></tr>`;
		html += `<tr><td>完成 / 目標</td><td>${ fmt( w.processed ) } / ${ fmt( w.target ) }</td></tr>`;
		html += `<tr><td>總耗時</td><td>${ fmt( w.elapsed_sec ) } 秒</td></tr>`;
		html += `<tr><td>平均速率</td><td><strong>${ fmt( w.rate_per_sec ) }</strong> users/sec</td></tr>`;
		html += `<tr><td>批次數</td><td>${ fmt( w.batches_done ) }</td></tr>`;
		html += `<tr><td>批次最快/平均/最慢</td><td>${ fmt( w.batch_min_ms ) } / ${ fmt( w.batch_avg_ms ) } / ${ fmt( w.batch_max_ms ) } ms</td></tr>`;
		html += `<tr><td>PHP Peak Memory</td><td>${ fmt( w.peak_memory_mb ) } MB</td></tr>`;
		html += '</tbody></table>';

		// DB sizes
		html += '<h4 style="margin-bottom:6px;">▍ DB 容量（user 相關表）</h4>';
		html += '<table class="widefat striped" style="margin-bottom:14px;"><thead><tr>';
		html += '<th>Table</th><th>Rows</th><th>Data MB</th><th>Index MB</th><th>Total MB</th><th>Avg bytes/row</th>';
		html += '</tr></thead><tbody>';
		dbSizes.forEach( ( r ) => {
			html += `<tr><td><code>${ esc( r.table ) }</code></td><td>${ fmt( r.rows ) }</td>`;
			html += `<td>${ r.data_mb ?? '—' }</td><td>${ r.index_mb ?? '—' }</td>`;
			html += `<td><strong>${ r.total_mb ?? '—' }</strong></td><td>${ fmt( r.avg_bytes ) }</td></tr>`;
		} );
		html += '</tbody></table>';

		// Query perf
		html += '<h4 style="margin-bottom:6px;">▍ 查詢效能</h4>';
		html += '<table class="widefat striped" style="margin-bottom:8px;"><thead><tr>';
		html += '<th>測試項目</th><th>樣本</th><th>總時間 (ms)</th><th>平均 (ms)</th><th>QPS</th>';
		html += '</tr></thead><tbody>';
		Object.keys( labels ).forEach( ( key ) => {
			const v = q[ key ];
			if ( ! v ) {
				return;
			}
			const total = v.total_ms ?? v.duration_ms ?? '—';
			html += `<tr><td>${ esc( labels[ key ] ) }</td><td>${ v.n || 1 }</td>`;
			html += `<td><strong>${ total }</strong></td><td>${ v.avg_ms ?? '—' }</td><td>${ v.qps ?? '—' }</td></tr>`;
		} );
		html += '</tbody></table>';
		html += '<p class="description">原生 EAV baseline 與 flat table 範圍查詢的時間差，即代表此規模下反 EAV 帶來的查詢加速倍數。</p>';

		content.innerHTML = html;
	}

	function setText( sel, text ) {
		const el = $( sel );
		if ( el ) {
			el.textContent = String( text );
		}
	}

	function esc( s ) {
		if ( s === null || s === undefined ) {
			return '';
		}
		return String( s ).replace( /[&<>"']/g, ( c ) => ( {
			'&': '&amp;',
			'<': '&lt;',
			'>': '&gt;',
			'"': '&quot;',
			"'": '&#39;',
		}[ c ] ) );
	}

	// ── Polling ─────────────────────────────────────────────────────────────

	async function poll() {
		const r = await apiCall( '/stress-test/status' );
		if ( ! r.ok || ! r.data ) {
			return;
		}
		renderProgress( r.data );
		if ( r.data.benchmark ) {
			renderBenchmark( r.data.benchmark );
		}
		if ( r.data.status !== 'running' && r.data.status !== 'benchmarking' ) {
			stopPolling();
		}
	}

	function startPolling() {
		stopPolling();
		poll();
		pollTimer = setInterval( poll, 2000 );
	}

	function stopPolling() {
		if ( pollTimer ) {
			clearInterval( pollTimer );
			pollTimer = null;
		}
	}

	// ── Event handlers ──────────────────────────────────────────────────────

	async function handleStart() {
		const target = parseInt( $( '#wpdo-st-target' ).value, 10 );
		let batch    = parseInt( $( '#wpdo-st-batch' ).value, 10 );
		const mode   = document.querySelector( 'input[name="wpdo-st-mode"]:checked' ).value;

		if ( ! target || target < 1 ) {
			alert( '請輸入有效的使用者數量' );
			return;
		}
		// Realistic 模式每 user ~3.5 秒，batch_size 太大會撞 nginx 60s timeout
		// 後端有 25s wall-clock deadline 保護，但前端先給友善提示
		if ( mode === 'realistic' && batch > 10 ) {
			if ( ! confirm( `Realistic 模式每個 user 約需 3 秒，batch_size=${ batch } 會超過後端 25s deadline 上限。建議使用 batch=10。要繼續嗎？` ) ) {
				return;
			}
		}
		const big = target >= 10000;
		const msg = `即將以 ${ mode } 模式建立 ${ target.toLocaleString() } 筆測試使用者${ big ? '（規模較大，可能耗時數分鐘）' : '' }。\n\n密碼一律為 PassWord2026!，user_login 為 test{n}。\n\n確定要開始嗎？`;
		if ( ! confirm( msg ) ) {
			return;
		}

		const r = await apiCall( '/stress-test/start', 'POST', { target, mode, batch_size: batch } );
		if ( ! r.ok ) {
			alert( '啟動失敗：' + ( r.data?.error || r.status ) );
			return;
		}
		// 啟動後立即顯示進度卡片，不必等第一次 poll 才出現
		const card = $( '#wpdo-st-progress-card' );
		if ( card ) {
			card.style.display = '';
		}
		setText( '#wpdo-st-pg-status', 'running' );
		setText( '#wpdo-st-pg-mode', mode );
		setText( '#wpdo-st-pg-target', target.toLocaleString() );
		startPolling();
	}

	async function handleCancel() {
		if ( ! confirm( '確定要取消當前測試？已建立的使用者不會被刪除。' ) ) {
			return;
		}
		// 立刻 UI 反饋：避免使用者再點一次
		const cancelBtn = $( '#wpdo-st-cancel' );
		if ( cancelBtn ) {
			cancelBtn.disabled    = true;
			cancelBtn.textContent = '⏹ 取消中…';
		}
		setText( '#wpdo-st-pg-status', 'cancelling' );

		const r = await apiCall( '/stress-test/cancel', 'POST' );
		if ( ! r.ok ) {
			alert( '取消失敗：' + ( r.data?.error || r.status ) );
			if ( cancelBtn ) {
				cancelBtn.disabled    = false;
				cancelBtn.textContent = '⏹ 取消';
			}
			return;
		}
		// realistic 模式 in-flight batch 可能還要 ~3 秒才會真正中止；polling 會看到 cancelled
		poll();
		if ( cancelBtn ) {
			cancelBtn.textContent = '⏹ 取消';
		}
	}

	async function handleCleanup() {
		if ( ! confirm( '確定要清除所有 test_* 使用者？\n\n此動作會：\n- DELETE 所有 user_login LIKE "test%" 的使用者\n- DELETE 對應 wp_usermeta\n- DELETE 所有 wp_wpdo_user_* flat tables 中對應 user_id 的列\n\n不可復原！' ) ) {
			return;
		}
		const r = await apiCall( '/stress-test/cleanup', 'DELETE' );
		if ( ! r.ok ) {
			alert( '清除失敗：' + ( r.data?.error || r.status ) );
			return;
		}
		alert( `已清除 ${ r.data.deleted } 筆測試使用者。` );
		const card = $( '#wpdo-st-progress-card' );
		const benchCard = $( '#wpdo-st-bench-card' );
		if ( card ) card.style.display = 'none';
		if ( benchCard ) benchCard.style.display = 'none';
		poll();
	}

	async function handleRerunBench() {
		const btn = $( '#wpdo-st-rerun-bench' );
		if ( btn ) {
			btn.disabled = true;
			btn.textContent = '⏳ 執行中...';
		}
		const r = await apiCall( '/stress-test/benchmark', 'POST' );
		if ( btn ) {
			btn.disabled = false;
			btn.textContent = '📊 重跑 Benchmark（不新增資料）';
		}
		if ( ! r.ok ) {
			alert( 'Benchmark 失敗：' + ( r.data?.error || r.status ) );
			return;
		}
		renderBenchmark( r.data.benchmark );
	}

	// ── Init ────────────────────────────────────────────────────────────────

	document.addEventListener( 'DOMContentLoaded', () => {
		const startBtn = $( '#wpdo-st-start' );
		const cancelBtn = $( '#wpdo-st-cancel' );
		const cleanupBtn = $( '#wpdo-st-cleanup' );
		const benchBtn = $( '#wpdo-st-rerun-bench' );

		if ( startBtn ) startBtn.addEventListener( 'click', handleStart );
		if ( cancelBtn ) cancelBtn.addEventListener( 'click', handleCancel );
		if ( cleanupBtn ) cleanupBtn.addEventListener( 'click', handleCleanup );
		if ( benchBtn ) benchBtn.addEventListener( 'click', handleRerunBench );

		// 初始 poll，如果正在執行就會自動開始 polling
		poll().then( () => {
			const card = $( '#wpdo-st-progress-card' );
			if ( card && card.style.display !== 'none' ) {
				const status = ( $( '#wpdo-st-pg-status' )?.textContent || '' ).trim();
				if ( status === 'running' || status === 'benchmarking' ) {
					startPolling();
				}
			}
		} );
	} );
} )();