package config

import (
	"encoding/json"
	"fmt"
	"os"
	"path/filepath"
	"time"
)

type Config struct {
	APIKey     string
	BaseURL    string
	Timeout    time.Duration
	MaxRetries int
	UserAgent  string
}

type FileConfig struct {
	APIKey string `json:"api_key"`
}

func New() *Config {
	apiKey := os.Getenv("DBORG_API_KEY")

	if apiKey == "" {
		if fileCfg, err := LoadConfig(); err == nil && fileCfg.APIKey != "" {
			apiKey = fileCfg.APIKey
		}
	}

	return &Config{
		APIKey:     apiKey,
		BaseURL:    "https://db.org.ai",
		Timeout:    30 * time.Second,
		MaxRetries: 3,
		UserAgent:  "dborg-cli/1.0",
	}
}

func (c *Config) WithAPIKey(key string) *Config {
	if key != "" {
		c.APIKey = key
	}
	return c
}

func (c *Config) Validate() error {
	if c.APIKey == "" {
		return ErrMissingAPIKey
	}
	return nil
}

func GetConfigPath() (string, error) {
	homeDir, err := os.UserHomeDir()
	if err != nil {
		return "", fmt.Errorf("failed to get home directory: %w", err)
	}

	configDir := filepath.Join(homeDir, ".config", "dborg")
	if err := os.MkdirAll(configDir, 0755); err != nil {
		return "", fmt.Errorf("failed to create config directory: %w", err)
	}

	return filepath.Join(configDir, "config.json"), nil
}

func LoadConfig() (*FileConfig, error) {
	configPath, err := GetConfigPath()
	if err != nil {
		return nil, err
	}

	data, err := os.ReadFile(configPath)
	if err != nil {
		if os.IsNotExist(err) {
			return &FileConfig{}, nil
		}
		return nil, fmt.Errorf("failed to read config file: %w", err)
	}

	var cfg FileConfig
	if err := json.Unmarshal(data, &cfg); err != nil {
		return nil, fmt.Errorf("failed to parse config file: %w", err)
	}

	return &cfg, nil
}

func SaveConfig(cfg *FileConfig) error {
	configPath, err := GetConfigPath()
	if err != nil {
		return err
	}

	data, err := json.MarshalIndent(cfg, "", "  ")
	if err != nil {
		return fmt.Errorf("failed to marshal config: %w", err)
	}

	if err := os.WriteFile(configPath, data, 0600); err != nil {
		return fmt.Errorf("failed to write config file: %w", err)
	}

	return nil
}