import { describe, expect, it } from 'vitest';
import type { GameLibrary, GameLibraryGame, GameLibraryVersion } from '../../src/lib/game-files.js';
import { latestGameFiles, selectLatestGameFiles } from '../../src/lib/ui/native-game-files.js';

function upload(
    id: string,
    game: GameLibraryGame = 't5',
    state: GameLibraryVersion['state'] = 'ready'
): GameLibraryVersion {
    return {
        id,
        libraryId: game,
        game,
        version: id,
        description: '',
        state,
        sizeBytes: 10,
        fileCount: 1,
        manifestSha256: 'manifest',
        files: [],
        createdAt: '2026-10-04T12:00:00Z',
        publishedAt: state === 'ready' ? '2026-10-04T12:05:00Z' : null,
        storageLocation: '',
        sourceHostId: null,
        sourceVolume: null,
        error: null,
        operationId: null,
        caches: []
    };
}

function slot(
    game: GameLibraryGame,
    latestVersionId: string | null,
    versions: GameLibraryVersion[]
): GameLibrary {
    return {
        id: game,
        name: game.toUpperCase(),
        game,
        description: '',
        createdAt: '',
        latestVersionId,
        versions
    };
}

describe('automatic game file selection for new launches', () => {
    it('follows the controller latest upload even when older files are already cached', () => {
        const old = upload('old');
        old.caches = [
            {
                hostId: 'host',
                libraryVersionId: old.id,
                status: 'ready',
                bytesDownloaded: 10,
                bytesTotal: 10,
                manifestSha256: 'manifest',
                error: null,
                updatedAt: '',
                operationId: null
            }
        ];
        const current = upload('latest');
        // The API can retain older uploads and unfinished uploads in its history.
        const libraries = [
            slot('t5', current.id, [upload('unfinished', 't5', 'importing'), old, current])
        ];
        const selected = { t5: old.id };
        const latest = latestGameFiles(libraries);

        expect(latest.t5).toBe(current);
        expect(selectLatestGameFiles(selected, latest, ['t5'])).toBe(true);
        expect(selected.t5).toBe(current.id);
        expect(selectLatestGameFiles(selected, latest, ['t5'])).toBe(false);
    });

    it('updates both games and removes a stale selection when a game has no available upload', () => {
        const latest = latestGameFiles([
            slot('t5', null, [upload('unavailable')]),
            slot('t6', 'new-t6', [upload('new-t6', 't6')])
        ]);
        const selected: Partial<Record<GameLibraryGame, string>> = { t5: 'old-t5', t6: 'old-t6' };

        expect(selectLatestGameFiles(selected, latest, ['t5', 't6'])).toBe(true);
        expect(selected).toEqual({ t6: 'new-t6' });
    });

    it('never selects an unfinished or missing latest upload from history', () => {
        expect(
            latestGameFiles([
                slot('t5', 'pending', [upload('old'), upload('pending', 't5', 'importing')])
            ])
        ).toEqual({});
        expect(latestGameFiles([slot('t6', 'missing', [upload('old', 't6')])])).toEqual({});
    });

    it('only changes games needed by the current launch', () => {
        const selected = { t5: 'old-t5', t6: 'keep-t6' };
        const latest = latestGameFiles([slot('t5', 'new-t5', [upload('new-t5')])]);

        expect(selectLatestGameFiles(selected, latest, ['t5'])).toBe(true);
        expect(selected).toEqual({ t5: 'new-t5', t6: 'keep-t6' });
    });
});