import { afterEach, beforeEach, expect, it, vi } from 'vitest';
import { newFixture, type Fixture } from '../helpers/fixture.js';
import { gameEvent, postTelemetry as post, roster, telemetryAuthHeaders } from '../helpers/telemetry.js';

let fixture: Fixture;
beforeEach(async () => {
    vi.resetModules();
    fixture = await newFixture();
    const { seedServerRegistry } = await import('../../src/lib/server/fleet/servers.js');
    await seedServerRegistry();
});
afterEach(async () => fixture.cleanup());

const payload = gameEvent('round_change', 17);

it('does not let a request received before a lifecycle submission restore cleared timers', async () => {
    const { db } = await import('../../src/lib/server/db/index.js');
    const { saveTelemetry } = await import('../../src/lib/server/fleet/telemetry.js');
    const { getServer } = await import('../../src/lib/server/fleet/servers.js');
    const at = (seconds: number) => new Date(Date.parse('2026-09-20T12:00:00Z') + seconds * 1000).toISOString();
    db().prepare('INSERT INTO restart_rollout (server, requested_at) VALUES (?, ?)').run(payload.server, at(10));
    for (const seconds of [9, 10]) {
        saveTelemetry({ ...gameEvent('game_start'), receivedAt: at(seconds) });
        expect(getServer(payload.server)).toMatchObject({ active_since: null, game_started_at: null });
    }
    const current = saveTelemetry({ ...gameEvent('heartbeat', 2), receivedAt: at(11) });
    expect(current.timing?.server).toEqual({ activeSince: at(11), inactiveSince: null, gameStartedAt: null, gameEndedAt: null });
});

it('generates timer anchors on the server instead of accepting client-supplied timing', async () => {
    const response = await post({ ...gameEvent('game_start'), receivedAt: '2000-01-01T00:00:00Z',
        timing: { server: { activeSince: '2000-01-01T00:00:00Z' } } });
    const { telemetry } = await response.json();
    expect(response.status).toBe(200);
    expect(telemetry.receivedAt).not.toBe('2000-01-01T00:00:00Z');
    expect(telemetry.timing.server).toEqual({ activeSince: telemetry.receivedAt, inactiveSince: null,
        gameStartedAt: telemetry.receivedAt, gameEndedAt: null });
});

it('persists player timing across matches and resets after absence or a telemetry gap', async () => {
    const { saveTelemetry, listTelemetry } = await import('../../src/lib/server/fleet/telemetry.js');
    const { closeDb } = await import('../../src/lib/server/db/index.js');
    const guid = roster(1)[0].guid;
    const at = (seconds: number) => new Date(Date.parse('2026-09-20T12:00:00Z') + seconds * 1000).toISOString();
    const save = (event: Parameters<typeof gameEvent>[0], seconds: number, round = 1, players = 1) =>
        saveTelemetry({ ...gameEvent(event, round, players), receivedAt: at(seconds) });
    save('game_start', 0);
    save('heartbeat', 60, 5);
    const end = save('game_end', 90, 6);
    expect(end.timing?.players[guid]).toEqual({ serverJoinedAt: at(0), matchJoinedAt: at(0), roundStarted: 1 });
    const next = save('game_start', 100);
    expect(next.timing?.players[guid]).toEqual({ serverJoinedAt: at(0), matchJoinedAt: at(100), roundStarted: 1 });
    closeDb();
    expect(listTelemetry()[0].timing).toEqual(next.timing);
    save('heartbeat', 120, 2, 0);
    expect(save('heartbeat', 140, 3).timing?.players[guid]).toEqual({
        serverJoinedAt: at(140), matchJoinedAt: at(140), roundStarted: 3
    });
    expect(save('heartbeat', 400, 8).timing?.players[guid]).toEqual({
        serverJoinedAt: at(400), matchJoinedAt: at(400), roundStarted: 8
    });
    expect(save('heartbeat', 420, 1).timing?.players[guid]).toEqual({
        serverJoinedAt: at(400), matchJoinedAt: at(420), roundStarted: 1
    });
});

it('timestamps initial telemetry and subsequent status and telemetry events with the server clock', async () => {
    const { GET } = await import('../../src/routes/api/events/servers/+server.js');
    const { emit } = await import('../../src/lib/server/pipeline/bus.js');
    const startedAt = Date.parse('2026-09-19T12:00:00Z');
    const clock = vi.spyOn(Date, 'now').mockReturnValue(startedAt);
    const reader = (await GET()).body!.getReader();
    const nextEvent = async () => {
        const frame = new TextDecoder().decode((await reader.read()).value);
        return JSON.parse(frame.split('\n').find(line => line.startsWith('data: '))!.slice(6));
    };
    try {
        await reader.read(); // Initial SSE comment.
        expect(await nextEvent()).toMatchObject({ snapshot: true, serverNow: startedAt, entries: expect.any(Array) });
        expect(await nextEvent()).toMatchObject({ snapshot: true, entries: [], serverNow: startedAt });
        clock.mockReturnValue(startedAt + 30_000);
        emit({ type: 'server-status', entries: [] });
        expect(await nextEvent()).toEqual({ type: 'server-status', entries: [], serverNow: startedAt + 30_000 });
        clock.mockReturnValue(startedAt + 31_000);
        emit({ type: 'server-telemetry', entries: [] });
        expect(await nextEvent()).toEqual({ type: 'server-telemetry', entries: [], serverNow: startedAt + 31_000 });
    } finally {
        await reader.cancel();
        clock.mockRestore();
    }
});

it('serializes each live server event once across connections and releases cancelled subscribers', async () => {
    const { GET } = await import('../../src/routes/api/events/servers/+server.js');
    const { emit } = await import('../../src/lib/server/pipeline/bus.js');
    const readers = await Promise.all([GET(), GET()].map(async response => (await response).body!.getReader()));
    const stringify = vi.spyOn(JSON, 'stringify');
    try {
        for (const reader of readers) {
            await reader.read(); // Initial comment and per-connection snapshots.
            await reader.read();
            await reader.read();
        }
        for (const event of [
            { type: 'server-status' as const, delta: true, entries: [] },
            { type: 'server-telemetry' as const, entries: [{ ...payload, receivedAt: new Date().toISOString() }] }
        ]) {
            stringify.mockClear();
            emit(event);
            expect(stringify).toHaveBeenCalledTimes(1);
            const [first, second] = await Promise.all(readers.map(reader => reader.read()));
            expect(first.value).toBe(second.value);
            const frame = new TextDecoder().decode(first.value);
            expect(frame.startsWith(`event: ${event.type}\ndata: `)).toBe(true);
            expect(JSON.parse(frame.split('\n')[1].slice(6))).toEqual({ ...event, serverNow: expect.any(Number) });
        }
        await readers[0].cancel();
        stringify.mockClear();
        emit({ type: 'server-status', entries: [] });
        expect(stringify).toHaveBeenCalledTimes(1);
        expect((await readers[1].read()).done).toBe(false);
        await readers[1].cancel();
        stringify.mockClear();
        emit({ type: 'server-telemetry', entries: [] });
        expect(stringify).not.toHaveBeenCalled();
    } finally {
        stringify.mockRestore();
        await Promise.all(readers.map(reader => reader.cancel()));
    }
});

it.each(['round_change', 'heartbeat'] as const)('persists %s stats, broadcasts updates, and leaves RCON safety data untouched', async (event) => {
    const payload = gameEvent(event, 17);
    const { subscribe } = await import('../../src/lib/server/pipeline/bus.js');
    const listener = vi.fn();
    const unsubscribe = subscribe(listener);
    expect(await (await post(payload)).json()).toEqual({ ok: true, telemetry: { ...payload, receivedAt: expect.any(String), timing: expect.any(Object) } });
    expect(listener).toHaveBeenCalledWith({ type: 'server-telemetry', entries: [{ ...payload, receivedAt: expect.any(String), timing: expect.any(Object) }] });
    unsubscribe();
    await post({ ...payload, round: 1 });
    const { closeDb } = await import('../../src/lib/server/db/index.js');
    closeDb();
    const { listTelemetry } = await import('../../src/lib/server/fleet/telemetry.js');
    expect(listTelemetry()).toEqual([{ ...payload, round: 1, receivedAt: expect.any(String), timing: expect.any(Object) }]);
    const { getServer } = await import('../../src/lib/server/fleet/servers.js');
    expect(getServer(payload.server)?.last_players).toBeNull();
    const { GET } = await import('../../src/routes/api/events/servers/+server.js');
    const reader = (await GET()).body!.getReader();
    await reader.read();
    const snapshot = new TextDecoder().decode((await reader.read()).value);
    expect(snapshot).toContain('"round":1');
    expect(snapshot).toContain('"headshots":50');
    expect(snapshot).toContain('"guid":"12345678901234560"');
    await reader.cancel();
});

it('accepts all four events without an active beta and updates match lifecycle', async () => {
    const { getServer } = await import('../../src/lib/server/fleet/servers.js');
    const { listTelemetry } = await import('../../src/lib/server/fleet/telemetry.js');
    const start = gameEvent('game_start');
    expect((await post(start)).status).toBe(200);
    expect(listTelemetry()).toEqual([{ ...start, receivedAt: expect.any(String), timing: expect.any(Object) }]);
    expect(getServer(start.server)?.game_started_at).toBeTruthy();
    expect(getServer(start.server)?.game_ended_at).toBeNull();
    expect((await post(payload)).status).toBe(200);
    const startedAt = getServer(start.server)?.game_started_at;
    const heartbeat = gameEvent('heartbeat', 17);
    expect((await post(heartbeat)).status).toBe(200);
    expect(listTelemetry()[0]).toMatchObject(heartbeat);
    expect(getServer(start.server)?.game_started_at).toBe(startedAt);
    expect(getServer(start.server)?.game_ended_at).toBeNull();
    const end = gameEvent('game_end', 18);
    expect((await post(end)).status).toBe(200);
    expect(getServer(start.server)?.game_ended_at).toBeTruthy();
    expect(listTelemetry()[0]).toMatchObject(end);
    await post(start);
    expect(listTelemetry()[0]).not.toHaveProperty('round');
    expect(getServer(start.server)?.game_ended_at).toBeNull();
    expect((await post(gameEvent('game_start', 0, 0))).status).toBe(200);
    expect((await post(gameEvent('game_end', 0, 0))).status).toBe(200);
});

it.each([null, [], {}, ...['boot', 'session_start', 'match_end', 'feature', 'other'].map(event => ({ ...payload, event })),
    { ...payload, map: '' }, { ...payload, map: undefined }, { ...payload, round: -1 },
    { ...payload, round: 1.5 }, { ...payload, round: '17' }, { ...payload, players: 4 }, { ...payload, players: null },
    { ...payload, players: [null] }, { ...payload, players: [{ name: 'Josh', guid: '123' }] },
    ...['name', 'guid', 'kills', 'headshots', 'downs', 'revives', 'score'].map(field => ({ ...payload, players: [{ ...roster(1)[0], [field]: null }] })),
    { ...payload, players: [{ ...roster(1)[0], guid: 12345678901234567 }] },
    { ...payload, players: [{ ...roster(1)[0], score: -1 }] }
])('rejects invalid telemetry: %j', async (body) => {
    expect((await post(body)).status).toBe(400);
});

it.each([
    { ...gameEvent('heartbeat'), round: undefined },
    { ...gameEvent('heartbeat'), round: -1 },
    { ...gameEvent('heartbeat'), players: [{ name: 'Player', guid: '123' }] },
    { ...gameEvent('heartbeat'), players: [{ ...roster(1)[0], kills: -1 }] }
])('requires round and full stats for heartbeats: %j', async (body) => {
    expect((await post(body)).status).toBe(400);
});

it('rejects unknown and destroyed servers and non-JSON requests', async () => {
    expect((await post({ ...payload, server: 'unknown' })).status).toBe(404);
    expect((await post(payload, 'text/plain')).status).toBe(415);
    const { setServerField } = await import('../../src/lib/server/fleet/servers.js');
    setServerField(payload.server, 'destroyed_at', new Date().toISOString());
    expect((await post(payload)).status).toBe(404);
});

it('rejects malformed JSON', async () => {
    const { POST } = await import('../../src/routes/api/telemetry/+server.js');
    expect((await POST({ request: new Request('http://localhost/api/telemetry', {
        method: 'POST', headers: { 'Content-Type': 'application/json', ...telemetryAuthHeaders() }, body: '{'
    }) })).status).toBe(400);
});

it('migrates old round-only storage without fabricating player identities', async () => {
    const { db, closeDb } = await import('../../src/lib/server/db/index.js');
    db().exec('DROP TABLE server_telemetry; CREATE TABLE server_telemetry (server TEXT PRIMARY KEY, round INTEGER NOT NULL, players INTEGER NOT NULL, received_at TEXT NOT NULL)');
    db().prepare('INSERT INTO server_telemetry VALUES (?, ?, ?, ?)').run(payload.server, 99, 4, new Date().toISOString());
    closeDb();
    const { listTelemetry } = await import('../../src/lib/server/fleet/telemetry.js');
    expect(listTelemetry()).toEqual([]);
    await post(payload);
    closeDb();
    expect(listTelemetry()[0]).toMatchObject(payload);
});