// Package config loads runtime configuration from environment variables.
//
// Vars prefixed with ANALYTICS_ are owned by this service; un-prefixed ones
// (POSTGRES_DSN, REDIS_ADDR, CLICKHOUSE_*) are shared with cdp-ingestion.
package config

import (
	"fmt"
	"time"

	"github.com/caarlos0/env/v11"
)

type Config struct {
	HTTPAddr        string        `env:"ANALYTICS_HTTP_ADDR"               envDefault:":4000"`
	LogLevel        string        `env:"ANALYTICS_LOG_LEVEL"               envDefault:"info"`
	ShutdownTimeout time.Duration `env:"ANALYTICS_SHUTDOWN_TIMEOUT_SECONDS" envDefault:"30s"`

	// Cache TTLs — configurable per query type.
	CacheTTLQuery   time.Duration `env:"ANALYTICS_CACHE_TTL_QUERY_SECONDS"   envDefault:"60s"`
	CacheTTLProfile time.Duration `env:"ANALYTICS_CACHE_TTL_PROFILE_SECONDS" envDefault:"30s"`

	// Where ClickHouse SQL templates live on disk. Resolved relative to the
	// process working directory; default matches `cd api && go run ./cmd/server`.
	ClickHouseTemplatesDir string `env:"ANALYTICS_CH_TEMPLATES_DIR" envDefault:"../infra/clickhouse"`

	// Custom SQL ClickHouse credentials — separate read-only user.
	ClickHouseSQLUser     string `env:"ANALYTICS_CH_SQL_USER"     envDefault:"analytics_ro"`
	ClickHouseSQLPassword string `env:"ANALYTICS_CH_SQL_PASSWORD"`

	// Shared infra ----------------------------------------------------------
	PostgresDSN string `env:"POSTGRES_DSN,required"`
	RedisAddr   string `env:"REDIS_ADDR" envDefault:"localhost:6379"`

	ClickHouseAddr     string `env:"CLICKHOUSE_ADDR"     envDefault:"localhost:9000"`
	ClickHouseDB       string `env:"CLICKHOUSE_DB"       envDefault:"cdp"`
	ClickHouseUser     string `env:"CLICKHOUSE_USER"     envDefault:"default"`
	ClickHousePassword string `env:"CLICKHOUSE_PASSWORD"`
	ClickHouseSecure   bool   `env:"CLICKHOUSE_SECURE"   envDefault:"false"`
}

func Load() (*Config, error) {
	cfg := &Config{}
	if err := env.Parse(cfg); err != nil {
		return nil, fmt.Errorf("config load: %w", err)
	}
	return cfg, nil
}