import { beforeEach, expect, it, vi } from 'vitest';
import { render } from 'svelte/server';
import type { MetricsData, MapMetrics, ServerMetrics } from '../../src/lib/metrics.js';
import MetricsPage from '../../src/routes/metrics/+page.svelte';
import MetricsSummary from '../../src/lib/ui/components/metrics/MetricsSummary.svelte';
import MetricsTables from '../../src/lib/ui/components/metrics/MetricsTables.svelte';
import MetricsExplore from '../../src/lib/ui/components/metrics/MetricsExplore.svelte';
import MetricsChart from '../../src/lib/ui/components/metrics/MetricsChart.svelte';
import { metricPage } from '../../src/lib/ui/metrics.js';
import { page } from '$app/state';

vi.mock('$app/state', () => ({ page: { url: new URL('http://localhost/metrics'), state: {} } }));
vi.mock('$app/navigation', () => ({
    beforeNavigate: vi.fn(),
    afterNavigate: vi.fn(),
    goto: vi.fn(),
    replaceState: vi.fn()
}));
const map = (i: number, changes: Partial<MapMetrics> = {}): MapMetrics => ({
    game: 't5',
    map: `Map ${String(i).padStart(2, '0')}`,
    observed: 10,
    active: 5,
    idle: 5,
    unknown: 0,
    playerHours: i,
    noEmpty: 1,
    availabilityObserved: 4,
    availabilityUnknown: 0,
    noEmptyAtMaximum: 0,
    noEmptyBelowMaximum: 0,
    policy: null,
    ...changes
});
const server = (i: number): ServerMetrics => ({
    server: `t5_zombie_theater_${i}`,
    currentRegistered: i !== 1,
    observed: 10,
    active: i / 10,
    idle: 10 - i / 10,
    unknown: 0,
    playerHours: i
});
function report(): MetricsData {
    const now = Date.parse('2026-10-06T12:00:00Z');
    const summary = { observed: 10, active: 5, idle: 5, unknown: 2, playerHours: 20 };
    return {
        days: 7,
        since: now - 7 * 86400000,
        now,
        firstRetainedSampleAt: now - 14 * 86400000,
        latestSampleAt: now,
        registeredServerCount: 24,
        scope: { game: null, map: null, timeZone: 'America/New_York' },
        scopeOptions: { games: ['t5'], maps: [] },
        scopeFirstSampleAt: now - 14 * 86400000,
        scopeLatestSampleAt: now,
        summary,
        running: { average: 12, peak: 24, capturedHours: 1 },
        maps: Array.from({ length: 24 }, (_, i) => map(i + 1)),
        servers: Array.from({ length: 24 }, (_, i) => server(i + 1)),
        points: [
            {
                ...summary,
                at: now - 86400000,
                startAt: now - 86400000,
                endAt: now,
                partial: true,
                capturedHours: 1
            }
        ],
        previous: {
            since: now - 14 * 86400000,
            until: now - 7 * 86400000,
            summary: { ...summary, active: 4, idle: 6, playerHours: 10 },
            running: { average: 12, peak: 24, capturedHours: 1 },
            firstSampleAt: now - 14 * 86400000,
            lastSampleAt: now - 7 * 86400000,
            partialHistory: true
        },
        pooledAvailability: {
            value: 25,
            noEmptyMapHours: 1,
            knownMapHours: 4,
            unknownMapHours: 0,
            coveredMaps: 24,
            totalMaps: 24
        },
        heatmap: { timeZone: 'America/New_York', cells: [] }
    };
}
function scope(search: string, stateSearch?: string) {
    Object.assign(page, {
        url: new URL(`http://localhost/metrics${search}`),
        state: stateSearch ? { metricsTableSearch: stateSearch } : {}
    });
}
beforeEach(() => scope(''));

it('shows a summary and one paginated breakdown, preserving scope on range links', () => {
    scope('?game=t5&days=7&view=maps&mapPage=2');
    const body = render(MetricsPage, {
        props: { data: { ...report(), user: null, setupRequired: false } }
    }).body;
    expect(body).toContain('aria-label="Metrics breakdown"');
    expect(body).toContain('aria-label="Map metrics table"');
    expect(body).not.toContain('aria-label="Instance metrics table"');
    expect(body.replace(/\s+/g, ' ')).toContain('16–24 of 24 maps');
    expect(body).toContain('game=t5&amp;days=30&amp;view=maps');
    expect(body).toContain('Partial previous history');
    expect(body).toContain('About this report');
    expect(body).toContain('Average lobbies running:');
    expect(body.replace(/\s+/g, ' ')).toContain('Captured wall time:');
    expect(body).not.toContain('Percentage points show');
    expect(body).not.toContain('Explore this period');
    expect(body).toContain('Updates every minute');
    expect(body).not.toContain('>Refresh<');
    const heatmap = body.slice(
        body.indexOf('class="heatmap'),
        body.indexOf('aria-label="Metrics breakdown"')
    );
    expect(heatmap).toContain('<h2');
    expect(heatmap).toContain('Activity by weekday and hour');
    expect(body).not.toContain('class="weekly');
});

it('shows concurrent lobbies and empty spare share with unknown lobby-hours in the denominator', () => {
    const data = report();
    let body = render(MetricsSummary, { props: { report: data } }).body;
    expect(body).toContain('12 avg');
    expect(body).toContain('Peak 24 lobbies at once');
    expect(body.replace(/\s+/g, ' ')).toContain(
        '5 h of 12 h captured lobby-hours were empty spares (41.7%)'
    );
    expect(body).toContain('+100%');
    expect(body).toContain('Time with no empty lobby');
    expect(body).toContain('25.0%');
    expect(body).not.toContain('capacity data');
    data.pooledAvailability = {
        value: null,
        noEmptyMapHours: 0,
        knownMapHours: 0,
        unknownMapHours: 4,
        coveredMaps: 0,
        totalMaps: 24
    };
    data.maps = [map(1, { availabilityObserved: 0, availabilityUnknown: 4 })];
    data.previous.summary.playerHours = 0;
    body = render(MetricsSummary, { props: { report: data } }).body;
    expect(body).toContain('Lobby availability unavailable');
    expect(body).toContain('New · no previous player-hours');
    expect(body).not.toContain('Infinity');
    data.summary = { observed: 0, active: 0, idle: 0, playerHours: 0, unknown: 12 };
    body = render(MetricsSummary, { props: { report: data } }).body;
    expect(body).toContain('Comparison unavailable');
    expect(body).toContain('12 avg');
    expect(body.replace(/\s+/g, ' ')).toContain(
        '0 h of 12 h captured lobby-hours were empty spares (0.0%)'
    );
    data.running = { average: null, peak: 0, capturedHours: 0 };
    data.summary.unknown = 0;
    body = render(MetricsSummary, { props: { report: data } }).body;
    expect(body).toContain('Peak unavailable');
    expect(body).not.toContain('Peak 0 lobbies');
});

it('searches and sorts the complete map set before pagination and clamps invalid pages', () => {
    const data = report();
    scope('?mapPage=2');
    let body = render(MetricsTables, { props: { maps: data.maps, servers: data.servers } }).body;
    expect(body).toContain('Map 09');
    expect(body).not.toContain('Map 24');
    scope('?mapPage=2', '?mapQ=Map+24&mapPage=100&mapSort=playerHours');
    body = render(MetricsTables, { props: { maps: data.maps, servers: data.servers } }).body;
    expect(body).toContain('Map 24');
    expect(body.replace(/\s+/g, ' ')).toContain('1–1 of 1 maps');
    expect(body).not.toContain('>Next<');
    expect(metricPage(data.maps, '-1').page).toBe(1);
    expect(metricPage(data.maps, 'Infinity').page).toBe(1);
    expect(metricPage([], '20')).toMatchObject({ page: 1, start: 0, end: 0, total: 0 });
});

it('keeps unknown availability last when sorting and distinguishes it from known empty lobbies', () => {
    scope('?mapSort=noEmpty&mapDirection=asc');
    const maps = [
        map(1, { availabilityObserved: 0, availabilityUnknown: 4 }),
        map(2, { noEmpty: 0 }),
        map(3)
    ];
    const body = render(MetricsTables, { props: { maps, servers: [] } }).body;
    expect(body.indexOf('Map 02')).toBeLessThan(body.indexOf('Map 03'));
    expect(body.indexOf('Map 03')).toBeLessThan(body.indexOf('Map 01'));
    expect(body).toContain('0.0%');
    expect(body).toContain('Lobby availability unavailable');
    expect(body).toContain('No empty lobby');
    expect(body).not.toContain('All lobbies full');
});

it('preserves instance return context and distinguishes historic names without current links', () => {
    scope('?view=instances&serverQ=theater&days=30');
    const body = render(MetricsTables, {
        props: { maps: [], servers: [server(1), server(2)], view: 'instances' }
    }).body;
    expect(body).toContain('Historical');
    expect(body).not.toContain('href="/servers/t5_zombie_theater_1');
    expect(body).toContain('href="/servers/t5_zombie_theater_2?returnTo=');
    expect(body).toContain('serverQ%3Dtheater');
    expect(body).not.toContain('>Idle</button>');
    expect(body).not.toContain('Open current server');
});

it('highlights at most three supported policy changes and collapses tentative findings', () => {
    const data = report();
    data.maps.push(map(25, { observed: 0.1, active: 0.1, idle: 0, availabilityObserved: 0 }));
    const body = render(MetricsExplore, { props: { report: data } }).body;
    const fold = body.indexOf('Other findings');
    expect(body.slice(0, fold).match(/class="recommendation /g)).toHaveLength(3);
    expect(body.indexOf('Map 25')).toBeGreaterThan(fold);
    expect(body).toContain('Limited evidence');
    expect(body).not.toMatch(/<details[^>]*open/);
    data.maps = [map(1, { availabilityObserved: 0 })];
    expect(render(MetricsExplore, { props: { report: data } }).body).toContain(
        'No policy changes meet the evidence threshold'
    );
});

it('keeps accessible chart selection, partial periods and gaps while collapsing inspection controls', () => {
    const data = report();
    data.points.push({
        at: data.now,
        startAt: data.now,
        endAt: data.now + 1000,
        partial: false,
        observed: 0,
        active: 0,
        idle: 0,
        unknown: 0,
        playerHours: 0,
        capturedHours: 0
    });
    const body = render(MetricsChart, {
        props: { points: data.points, days: data.days, timeZone: data.scope.timeZone }
    }).body;
    expect(body).toContain('aria-label="Selected period summary"');
    expect(body).toContain('No captured time · not evidence of empty lobbies');
    expect(body).toContain('tabindex="0"');
    expect(body).toContain('Inspect a period');
    expect(body).toContain('Partial period');
    expect(body).not.toMatch(/<details[^>]*open/);
    expect(body).toContain('Weekdays show when each period starts in America/New York.');
    expect(body).toContain('Daily periods are 24-hour windows.');
    expect(body).toContain('Lobbies running over time');
    expect(body).toContain('Average lobbies running');
    expect(body).toContain('5 with players · 5 empty spares · 2 unknown on average');
});

it('keeps average lobby bar heights comparable across partial periods and collection gaps', () => {
    const data = report();
    const point = data.points[0];
    data.points = [
        {
            ...point,
            observed: 48,
            active: 12,
            idle: 36,
            unknown: 24,
            capturedHours: 12,
            partial: false
        },
        {
            ...point,
            at: data.now,
            startAt: data.now,
            endAt: data.now + 2 * 3600000,
            observed: 8,
            active: 2,
            idle: 6,
            unknown: 4,
            capturedHours: 2,
            partial: true
        }
    ];
    const body = render(MetricsChart, {
        props: { points: data.points, days: data.days, timeZone: data.scope.timeZone }
    }).body;
    const bars = body.match(/<button class="bar\b[\s\S]*?<\/button>/g) ?? [];
    expect(bars).toHaveLength(2);
    const heights = bars.map((bar) =>
        [...bar.matchAll(/style="height:\s*([^"]+)"/g)].map((match) => match[1])
    );
    expect(heights[0]).toHaveLength(3);
    expect(heights[0]).toEqual(heights[1]);
    expect(heights[0]).toContain('50%;');
    expect(
        bars.every((bar) => bar.includes('1 with players · 3 empty spares · 2 unknown on average'))
    ).toBe(true);
});

it('uses shallow URL state for the selected breakdown while retaining the common summary', () => {
    scope('?view=maps', '?view=instances&serverQ=theater&serverPage=2');
    let body = render(MetricsPage, {
        props: { data: { ...report(), user: null, setupRequired: false } }
    }).body;
    expect(body).toContain('aria-label="Instance metrics table"');
    expect(body).not.toContain('aria-label="Map metrics table"');
    expect(body.replace(/\s+/g, ' ')).toContain('16–24 of 24 instances');
    scope('?view=maps', '?view=insights');
    body = render(MetricsPage, {
        props: { data: { ...report(), user: null, setupRequired: false } }
    }).body;
    expect(body).toContain('id="metrics-explore-title"');
    expect(body).toContain('Time with no empty lobby');
    expect(body).toContain('Autoscaling signals');
    expect(body).not.toContain('aria-label="Map metrics table"');
    expect(body).not.toContain('aria-label="Instance metrics table"');
});

it('filters other signals without hiding the highlighted supported policy changes', () => {
    scope('?view=insights&insightQ=Map+24&insightSort=map');
    const body = render(MetricsExplore, { props: { report: report() } }).body;
    expect(body).toContain('Map 01');
    expect(body).toContain('Map 24');
    expect(body).not.toContain('Map 23');
});

it('links autoscaling signals to current policies and explains their historical comparison', () => {
    const data = report();
    data.maps = [
        map(1, {
            noEmptyAtMaximum: 0.75,
            noEmptyBelowMaximum: 0.25,
            policy: {
                id: 'policy-1',
                mode: 'create-destroy',
                minimum: 1,
                maximum: 3,
                spares: 1,
                pausedReason: null
            }
        })
    ];
    let body = render(MetricsExplore, { props: { report: data } }).body;
    expect(body).toContain('href="/autoscaling#policy-1"');
    expect(body).toContain('Review policy');
    expect(body).toContain('Current policy: 1–3 lobbies, 1 spare');
    expect(body.replace(/\s+/g, ' ')).toContain(
        'Current settings are applied to historical lobby counts'
    );
    expect(body).not.toContain('player limits, and observation');
    data.maps[0].policy = null;
    body = render(MetricsExplore, { props: { report: data } }).body;
    expect(body).toContain('href="/autoscaling"');
    expect(body).toContain('Add policy');
});