package config

import (
	"fmt"
	"os"
	"strconv"
	"time"
)

type Config struct {
	Env                        string
	Host                       string
	Port                       int
	Database                   DatabaseConfig
	Meilisearch                MeilisearchConfig
	Redis                      RedisConfig
	Equalize                   EqualizeConfig
	S3                         S3Config
	EnablePersistTask          bool
	EnableImpedancePersistTask bool
	ShareCodeMaxPerMac         int
	ShareCodeTTL               time.Duration
}

func Load() (*Config, error) {
	port, err := strconv.Atoi(getEnv("APP_PORT", "8080"))
	if err != nil {
		return nil, fmt.Errorf("invalid APP_PORT: %w", err)
	}

	env := getEnv("APP_ENV", "development")

	db, err := loadDatabase()
	if err != nil {
		return nil, err
	}
	if err := db.validate(); err != nil {
		return nil, err
	}

	ms := loadMeilisearch()
	if err := ms.validate(); err != nil {
		return nil, err
	}

	rd := loadRedis()
	if err := rd.validate(); err != nil {
		return nil, err
	}

	eq := loadEqualize()
	s3cfg := loadS3()

	shareCodeTTL, err := parseShareCodeTTL(getEnv("SHARE_CODE_TTL_MIN", "30"))
	if err != nil {
		return nil, fmt.Errorf("invalid SHARE_CODE_TTL_MIN: %w", err)
	}

	return &Config{
		Env:                        env,
		Host:                       getEnv("APP_HOST", "0.0.0.0"),
		Port:                       port,
		Database:                   db,
		Meilisearch:                ms,
		Redis:                      rd,
		Equalize:                   eq,
		S3:                         s3cfg,
		EnablePersistTask:          getEnv("ENABLE_PERSIST_TASK", "false") == "true",
		EnableImpedancePersistTask: getEnv("ENABLE_IMPEDANCE_PERSIST_TASK", "false") == "true",
		ShareCodeMaxPerMac:         getEnvInt("SHARE_CODE_MAX_PER_MAC", 1),
		ShareCodeTTL:               shareCodeTTL,
	}, nil
}

func (c *Config) Addr() string {
	return fmt.Sprintf("%s:%d", c.Host, c.Port)
}

func getEnv(key, fallback string) string {
	if v := os.Getenv(key); v != "" {
		return v
	}
	return fallback
}

func getEnvInt(key string, fallback int) int {
	v := os.Getenv(key)
	if v == "" {
		return fallback
	}
	n, err := strconv.Atoi(v)
	if err != nil {
		return fallback
	}
	return n
}