package app

import (
	"context"
	"fmt"
	"time"

	"github.com/gochat/gochat/internal/config"
	"github.com/gochat/gochat/pkg/logger"
	"github.com/redis/go-redis/v9"
)

// NewRedisClient creates a Redis client for caching, Pub/Sub, and sessions.
// Reference: Chatwoot config/cable.yml Redis adapter configuration
func NewRedisClient(cfg *config.RedisConfig) (*redis.Client, error) {
	opts, err := redis.ParseURL(cfg.DSN)
	if err != nil {
		return nil, fmt.Errorf("failed to parse Redis DSN: %w", err)
	}

	poolSize := cfg.PoolSize
	if poolSize <= 0 {
		poolSize = 50
	}
	opts.PoolSize = poolSize

	client := redis.NewClient(opts)

	// Verify connection
	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
	defer cancel()

	if err := client.Ping(ctx).Err(); err != nil {
		return nil, fmt.Errorf("failed to connect to Redis: %w", err)
	}

	logger.L().Infof("Connected to Redis: %s (db=%d, pool=%d)", opts.Addr, opts.DB, poolSize)

	return client, nil
}