import { describe, expect, it } from 'vitest';
import { resolveHookRuntimeDir } from '../src/hook-runtime-dir';

function procReader(files: Record<string, string>) {
    return (file: string): string => {
        const value = files[file];

        if (value === undefined) {
            throw new Error(`missing fixture: ${file}`);
        }

        return value;
    };
}

describe('resolveHookRuntimeDir — Linux target process ownership', () => {
    it('uses the QQ process runtime directory instead of the supervisor user directory', () => {
        expect(
            resolveHookRuntimeDir(46301, {
                platform: 'linux',
                env: { XDG_RUNTIME_DIR: '/run/user/0' },
                ownUid: 0,
                readText: procReader({
                    '/proc/46301/environ': 'HOME=/home/rikka\0XDG_RUNTIME_DIR=/run/user/1000\0',
                    '/proc/46301/status': 'Name:\tqq\nUid:\t1000\t1000\t1000\t1000\n',
                }),
            }),
        ).toBe('/run/user/1000');
    });

    it('falls back to the QQ process uid when its environment has no runtime directory', () => {
        expect(
            resolveHookRuntimeDir(46301, {
                platform: 'linux',
                env: { XDG_RUNTIME_DIR: '/run/user/0' },
                ownUid: 0,
                readText: procReader({
                    '/proc/46301/environ': 'HOME=/home/rikka\0',
                    '/proc/46301/status': 'Name:\tqq\nUid:\t1000\t1000\t1000\t1000\n',
                }),
            }),
        ).toBe('/tmp/snowluma-1000');
    });

    it('fails visibly when target ownership cannot be determined', () => {
        expect(() =>
            resolveHookRuntimeDir(46301, {
                platform: 'linux',
                env: { XDG_RUNTIME_DIR: '/run/user/0' },
                ownUid: 0,
                readText: () => {
                    throw new Error('permission denied');
                },
            }),
        ).toThrow(/cannot resolve hook runtime directory.*permission denied/);
    });

    it('uses the current convention when the target disappears during discovery', () => {
        const gone = Object.assign(new Error('process disappeared'), { code: 'ENOENT' });
        expect(
            resolveHookRuntimeDir(46301, {
                platform: 'linux',
                env: { XDG_RUNTIME_DIR: '/run/user/0' },
                ownUid: 0,
                readText: () => {
                    throw gone;
                },
            }),
        ).toBe('/run/user/0');
    });

    it('honours an explicit runtime directory inherited by the QQ process', () => {
        expect(
            resolveHookRuntimeDir(46301, {
                platform: 'linux',
                env: {},
                ownUid: 0,
                readText: procReader({
                    '/proc/46301/environ': 'SNOWLUMA_HOOK_RUNTIME_DIR=/srv/snowluma-hook\0',
                    '/proc/46301/status': 'Uid:\t1000\t1000\t1000\t1000\n',
                }),
            }),
        ).toBe('/srv/snowluma-hook');
    });
});