import { Body, Controller, Get, Patch, Req, UseGuards } from '@nestjs/common';
import { z } from 'zod';

import type { AuthedRequest } from '../auth/auth.guard';
import { ZodValidationPipe } from '../common/zod-validation.pipe';
import {
  INSTANCE_SETTINGS,
  InstanceSettingKey,
  InstanceSettings,
  InstanceSettingsService,
} from '../settings/instance-settings.service';
import { SiteAdminGuard } from './site-admin.guard';

// Lifecycle markers, not configuration: never editable through this
// endpoint (the setup lock must be irreversible, issue #80).
const INTERNAL_KEYS: ReadonlySet<InstanceSettingKey> = new Set(['setup.completedAt']);

// Partial update: any subset of the known settings, each validated by
// its own schema inside the service (double validation is fine — this
// outer schema only gates unknown and internal keys).
const patchSchema = z
  .object(
    Object.fromEntries(
      Object.keys(INSTANCE_SETTINGS)
        .filter((key) => !INTERNAL_KEYS.has(key as InstanceSettingKey))
        .map((key) => [key, z.unknown().optional()]),
    ) as Record<InstanceSettingKey, z.ZodOptional<z.ZodUnknown>>,
  )
  .strict();

@Controller('admin/settings')
@UseGuards(SiteAdminGuard)
export class AdminSettingsController {
  constructor(private readonly settings: InstanceSettingsService) {}

  @Get()
  getSettings(): Promise<InstanceSettings> {
    return this.settings.getAll();
  }

  @Patch()
  async patchSettings(
    @Body(new ZodValidationPipe(patchSchema)) input: Partial<Record<InstanceSettingKey, unknown>>,
    @Req() request: AuthedRequest,
  ): Promise<InstanceSettings> {
    for (const [key, value] of Object.entries(input)) {
      if (value === undefined) continue;
      await this.settings.set(key as InstanceSettingKey, value, request.user!.id);
    }
    return this.settings.getAll();
  }
}