import { BadRequestException, Injectable } from '@nestjs/common';
import { InjectDataSource } from '@nestjs/typeorm';
import { DataSource, In } from 'typeorm';
import { Site } from '../../entities';
import { AccessService } from '../../common/access.service';
import { AuthUser, requireOrg } from '../../common/auth';
import { assertMultiPolygon } from '../../common/geo';
import { obj, reqStr, str } from '../../common/input';
import { isValidTimeZone } from '../../common/time';

@Injectable()
export class SitesService {
  constructor(
    @InjectDataSource() private readonly db: DataSource,
    private readonly access: AccessService,
  ) {}

  async list(user: AuthUser) {
    const ids = await this.access.siteIds(user);
    if (!ids.length) return [];
    const sites = await this.db.getRepository(Site).find({ where: { id: In(ids) }, order: { name: 'ASC' } });
    const counts: { site_id: string; routes: number; rounds_today: number }[] = await this.db.query(
      `SELECT s.id AS site_id,
              (SELECT count(*)::int FROM routes r WHERE r.site_id = s.id AND r.archived_at IS NULL) AS routes,
              (SELECT count(*)::int FROM rounds o WHERE o.site_id = s.id
                 AND o.planned_start >= date_trunc('day', now() AT TIME ZONE s.timezone) AT TIME ZONE s.timezone
                 AND o.planned_start < (date_trunc('day', now() AT TIME ZONE s.timezone) + interval '1 day') AT TIME ZONE s.timezone
              ) AS rounds_today
       FROM sites s WHERE s.id = ANY($1)`,
      [ids],
    );
    const byId = new Map(counts.map((c) => [c.site_id, c]));
    return sites.map((s) => ({ ...s, routesCount: byId.get(s.id)?.routes ?? 0, roundsToday: byId.get(s.id)?.rounds_today ?? 0 }));
  }

  get(user: AuthUser, id: string) {
    return this.access.site(user, id);
  }

  // Проверяем геометрию средствами PostGIS и считаем центр для карты.
  private async geometry(perimeter: unknown) {
    if (perimeter === null) return { perimeter: null, center: null };
    const mp = assertMultiPolygon(perimeter, 'perimeter');
    const [row] = await this.db.query(
      `SELECT ST_IsValid(g) AS valid, ST_IsValidReason(g) AS reason, ST_AsGeoJSON(ST_PointOnSurface(g))::json AS center
       FROM (SELECT ST_SetSRID(ST_GeomFromGeoJSON($1), 4326) AS g) t`,
      [JSON.stringify(mp)],
    );
    if (!row.valid) throw new BadRequestException(`Периметр нарисован с ошибкой (${row.reason}). Проверьте, что стороны не пересекаются`);
    return { perimeter: mp, center: row.center };
  }

  private fields(o: Record<string, unknown>) {
    const timezone = str(o, 'timezone', { max: 64 });
    if (timezone && !isValidTimeZone(timezone)) throw new BadRequestException('Неизвестный часовой пояс');
    return {
      ...(o.name !== undefined ? { name: reqStr(o, 'name', { max: 300 }) } : {}),
      ...('address' in o ? { address: str(o, 'address', { max: 500 }) ?? null } : {}),
      ...('description' in o ? { description: str(o, 'description', { max: 5000 }) ?? null } : {}),
      ...(timezone ? { timezone } : {}),
    };
  }

  async create(user: AuthUser, body: unknown) {
    const orgId = requireOrg(user);
    const o = obj(body);
    reqStr(o, 'name');
    const geo = 'perimeter' in o ? await this.geometry(o.perimeter) : {};
    const site = await this.db.getRepository(Site).save({
      organizationId: orgId,
      createdBy: user.id,
      ...this.fields(o),
      ...geo,
    } as Partial<Site>);
    return this.access.site(user, site.id).catch(() => site);
  }

  async update(user: AuthUser, id: string, body: unknown) {
    await this.access.site(user, id);
    const o = obj(body);
    const geo = 'perimeter' in o ? await this.geometry(o.perimeter) : {};
    await this.db.getRepository(Site).update({ id }, { ...this.fields(o), ...geo } as Partial<Site>);
    return this.access.site(user, id);
  }

  async archive(user: AuthUser, id: string) {
    await this.access.site(user, id);
    await this.db.getRepository(Site).update({ id }, { archivedAt: new Date() });
    // Будущие обходы архивного объекта не нужны.
    await this.db.query(`UPDATE rounds SET status = 'cancelled', updated_at = now() WHERE site_id = $1 AND status = 'planned'`, [id]);
    return { id };
  }
}