import Database from 'better-sqlite3';
import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';
import schema from '../../src/lib/server/db/schema.sql?raw';
import { newFixture, type Fixture } from '../helpers/fixture.js';

let fixture: Fixture;
beforeEach(async () => {
    vi.resetModules();
    fixture = await newFixture([]);
});
afterEach(async () => {
    vi.restoreAllMocks();
    await fixture.cleanup();
});

describe('provisioning reads with retained lifecycle history', () => {
    it('uses indexed per-server submissions and separate lifecycle indexes for fleet reads', async () => {
        const { db } = await import('../../src/lib/server/db/index.js');
        const { latestGameSubmission, latestGameSubmissions } = await import('../../src/lib/server/fleet/lifecycle-evidence.js');
        const { observationReader } = await import('../../src/lib/server/fleet/status.js');
        const { runningVersions } = await import('../../src/lib/server/integrations/plutonium.js');
        const { fleetOperations } = await import('../../src/lib/server/fleet/overview.js');
        const handle = db();
        const now = Date.parse('2026-10-05T12:00:00Z');
        const iso = (offset: number) => new Date(now + offset).toISOString();
        handle.transaction(() => {
            const server = handle.prepare('INSERT INTO servers(name, komodo_name) VALUES (?, ?)');
            for (let i = 0; i < 16; i++) server.run(`server-${i}`, `server-${i}`);
            server.run('empty', 'empty');
            const insert = handle.prepare(`INSERT INTO server_deployments
                (id, server, action, state, stage, started_at, finished_at, submitted_at, server_deleted_at, triggered_by)
                VALUES (?, ?, ?, 'done', 'Complete', ?, ?, ?, ?, 'test')`);
            for (let i = 0; i < 6_000; i++) {
                const at = iso(-100_000_000 - i);
                insert.run(`history-${i}`, `server-${i % 16}`, 'restart', at, at, at, null);
            }
            for (const [i, action] of ['create', 'start', 'restart', 'rebuild'].entries()) {
                insert.run(`current-${i}`, `server-${i}`, action, iso(-1000), iso(-1000), iso(-1000), null);
            }
            insert.run('stop', 'server-0', 'stop', iso(0), iso(0), iso(0), null);
            insert.run('destroy', 'server-1', 'destroy', iso(0), iso(0), iso(0), null);
            insert.run('deleted', 'server-2', 'restart', iso(0), iso(0), iso(0), iso(0));
            insert.run('unsubmitted', 'server-3', 'rebuild', iso(0), null, null, null);
            handle.prepare('INSERT INTO restart_rollout(server, requested_at, healthy_at) VALUES (?, ?, ?)')
                .run('server-0', iso(-500), iso(0));
            handle.prepare('INSERT INTO restart_rollout(server, requested_at) VALUES (?, ?)').run('server-1', iso(-2000));
        })();
        const submissions = latestGameSubmissions();
        expect(submissions.get('empty')).toBeNull();
        expect(submissions.get('server-0')).toBe(iso(-500));
        for (const i of [1, 2, 3]) expect(submissions.get(`server-${i}`)).toBe(iso(-1000));
        for (const [server, at] of submissions) expect(at).toBe(latestGameSubmission(server));

        // Capture real snapshot queries so plan checks catch regressions at call sites.
        for (const read of [observationReader, runningVersions]) {
            const prepare = vi.spyOn(handle, 'prepare');
            read();
            const queries = prepare.mock.calls.map(([sql]) => sql).filter(sql => sql.includes('submitted_at'));
            prepare.mockRestore();
            expect(queries).toHaveLength(1);
            const plan = handle.prepare(`EXPLAIN QUERY PLAN ${queries[0]}`).all() as { detail: string }[];
            const details = plan.map(row => row.detail).join('\n');
            expect(details).toContain('SEARCH server_deployments USING COVERING INDEX idx_server_deployments_submission');
            expect(details).not.toMatch(/SCAN server_deployments\b/);
        }
        const prepare = vi.spyOn(handle, 'prepare');
        fleetOperations(now);
        const queries = prepare.mock.calls.map(([sql]) => sql).filter(sql => sql.includes('server_deployments'));
        prepare.mockRestore();
        expect(queries).toHaveLength(1);
        const statement = handle.prepare(queries[0]);
        expect(statement.columns().map(column => column.name)).toEqual(['id', 'server', 'action', 'state', 'stage', 'error', 'started_at']);
        const plan = handle.prepare(`EXPLAIN QUERY PLAN ${queries[0]}`).all() as { detail: string }[];
        const details = plan.map(row => row.detail).join('\n');
        expect(details).toContain('SEARCH server_deployments USING INDEX idx_server_deployments_state');
        expect(queries[0]).not.toContain('finished_at >=');
        expect(details).toContain('SEARCH server_deployments USING INTEGER PRIMARY KEY (rowid=?)');
        expect(details).toContain('SCAN server_deployments USING COVERING INDEX idx_server_deployments_server');
        expect(details).not.toMatch(/SCAN server_deployments(?:\n|$)/);
    });

    it('indexes the server and queue reads used by collection matching and health polling', async () => {
        const { db } = await import('../../src/lib/server/db/index.js');
        const { latestGameSubmission } = await import('../../src/lib/server/fleet/lifecycle-evidence.js');
        const { hasActiveProvisioning } = await import('../../src/lib/server/fleet/provisioning.js');
        const { housePartyTargets } = await import('../../src/lib/server/fleet/house-party.js');
        const { creationQueue } = await import('../../src/lib/server/provisioning/instances.js');
        const handle = db();
        handle.transaction(() => {
            const insert = handle.prepare(`INSERT INTO server_deployments
                (id,server,action,state,stage,started_at,triggered_by,server_deleted_at)
                VALUES(?,?,'create','done','Complete','2025-01-01','fixture','2025-01-02')`);
            for (let i = 0; i < 2_000; i++) insert.run(`history-${i}`, `retired-${i}`);
            handle.prepare(`INSERT INTO server_deployments
                (id,server,action,state,stage,started_at,triggered_by,submitted_at)
                VALUES('current','current','create','queued','Queued','2026-01-01','fixture','2026-01-01')`).run();
        })();

        // Inspect the SQL issued by the public reads, so the regression follows
        // those implementations rather than keeping separate copies of them.
        const expectIndexed = (read: () => unknown, bindings: string[] = []) => {
            const prepare = vi.spyOn(handle, 'prepare');
            read();
            const queries = prepare.mock.calls.map(([sql]) => sql).filter(sql => sql.includes('server_deployments'));
            prepare.mockRestore();
            expect(queries).toHaveLength(1);
            const plan = handle.prepare(`EXPLAIN QUERY PLAN ${queries[0]}`).all(...bindings) as { detail: string }[];
            const details = plan.map(row => row.detail).join('\n');
            expect(details).toMatch(/SEARCH server_deployments USING (?:COVERING )?INDEX/);
            expect(details).not.toMatch(/SCAN server_deployments\b/);
        };
        expectIndexed(() => expect(latestGameSubmission('current')).toBe('2026-01-01'), ['current', 'current']);
        expectIndexed(() => expect(hasActiveProvisioning('current')).toBe(true), ['current', '']);
        expectIndexed(() => expect(housePartyTargets()).toEqual(['current']));
        expectIndexed(() => expect(creationQueue().queued.map(job => job.id)).toEqual(['current']));
    });

    it('installs the indexes after legacy table rebuilds and keeps them on reopen', async () => {
        const legacy = new Database(fixture.dbPath);
        try {
            legacy.exec(schema.replace(/CREATE TABLE IF NOT EXISTS server_deployments \([\s\S]*?\n\);/, table => table
                .replace("'create', 'start', 'restart', 'rebuild', 'stop', 'destroy'", "'create', 'destroy'")
                .replace('    server_deleted_at TEXT,\n', '')));
            legacy.exec(`INSERT INTO servers(name,komodo_name) VALUES('existing','existing');
                INSERT INTO server_deployments(id,server,action,state,stage,started_at,triggered_by)
                    VALUES('old','existing','create','done','Complete','2025-01-01','fixture');
                INSERT INTO server_deployment_events(deployment_id,created_at,message)
                    VALUES('old','2025-01-01','Creation complete');`);
        } finally { legacy.close(); }
        const { db, closeDb } = await import('../../src/lib/server/db/index.js');
        for (let open = 0; open < 2; open++) {
            const handle = db();
            expect(handle.prepare('SELECT rowid,id,state FROM server_deployments').all())
                .toEqual([{ rowid: 1, id: 'old', state: 'done' }]);
            expect(handle.prepare('SELECT message FROM server_deployment_events').all()).toEqual([{ message: 'Creation complete' }]);
            const indexes = handle.pragma('index_list(server_deployments)') as { name: string }[];
            expect(indexes.map(index => index.name)).toEqual(expect.arrayContaining([
                'idx_server_deployments_server', 'idx_server_deployments_state', 'idx_server_deployments_started_at',
                'idx_server_deployments_submission', 'idx_server_deployments_finished_at'
            ]));
            expect(handle.pragma('foreign_key_check')).toEqual([]);
            closeDb();
        }
    });
});