import { Injectable, OnModuleDestroy } from '@nestjs/common';
import { ConfigService } from '@nestjs/config';
import Redis from 'ioredis';
import type { BuildProgress } from './build.service';

const KEY_PREFIX = 'build:progress:';
const TTL_SECONDS = 3600;

@Injectable()
export class BuildProgressStore implements OnModuleDestroy {
  private readonly redis: Redis;

  constructor(private readonly configService: ConfigService) {
    this.redis = new Redis({
      host: this.configService.get<string>('redis.host'),
      port: this.configService.get<number>('redis.port'),
      lazyConnect: true,
      maxRetriesPerRequest: 1,
    });
    this.redis.connect().catch(() => {
      // Redis may be unavailable in local unit tests — in-memory fallback remains in BuildService.
    });
  }

  async get(deploymentId: string): Promise<BuildProgress | null> {
    try {
      const raw = await this.redis.get(`${KEY_PREFIX}${deploymentId}`);
      return raw ? (JSON.parse(raw) as BuildProgress) : null;
    } catch {
      return null;
    }
  }

  async set(deploymentId: string, progress: BuildProgress): Promise<void> {
    try {
      await this.redis.set(
        `${KEY_PREFIX}${deploymentId}`,
        JSON.stringify(progress),
        'EX',
        TTL_SECONDS,
      );
    } catch {
      // Best-effort — local map still holds progress for this replica.
    }
  }

  async clear(deploymentId: string): Promise<void> {
    try {
      await this.redis.del(`${KEY_PREFIX}${deploymentId}`);
    } catch {
      // ignore
    }
  }

  onModuleDestroy(): void {
    this.redis.disconnect();
  }
}