package config

import (
	"fmt"
	"os"
	"path/filepath"

	"github.com/muyue/muyue/internal/secret"
	"gopkg.in/yaml.v3"
)

type Profile struct {
	Name        string   `yaml:"name"`
	Pseudo      string   `yaml:"pseudo"`
	Email       string   `yaml:"email"`
	Languages   []string `yaml:"languages"`
	Preferences struct {
		Editor         string `yaml:"editor"`
		Shell          string `yaml:"shell"`
		Theme          string `yaml:"theme"`
		DefaultAI      string `yaml:"default_ai"`
		AutoUpdate     bool   `yaml:"auto_update"`
		CheckOnStart   bool   `yaml:"check_on_start"`
		Language       string `yaml:"language"`
		KeyboardLayout string `yaml:"keyboard_layout"`
	} `yaml:"preferences"`
}

type AIProvider struct {
	Name     string `yaml:"name"`
	APIKey   string `yaml:"api_key,omitempty"`
	BaseURL  string `yaml:"base_url,omitempty"`
	Model    string `yaml:"model"`
	Active   bool   `yaml:"active"`
}

type ToolConfig struct {
	Name      string `yaml:"name"`
	Installed bool   `yaml:"installed"`
	Version   string `yaml:"version"`
	AutoUpdate bool  `yaml:"auto_update"`
}

type MuyueConfig struct {
	Version   string               `yaml:"version"`
	Profile   Profile              `yaml:"profile"`
	AI        struct {
		Providers []AIProvider      `yaml:"providers"`
	} `yaml:"ai"`
	Tools     []ToolConfig         `yaml:"tools"`
	BMAD      struct {
		Installed bool   `yaml:"installed"`
		Version   string `yaml:"version"`
		Global    bool   `yaml:"global"`
	} `yaml:"bmad"`
	Terminal struct {
		CustomPrompt bool   `yaml:"custom_prompt"`
		PromptTheme  string `yaml:"prompt_theme"`
	} `yaml:"terminal"`
}

func ConfigDir() (string, error) {
	configDir, err := os.UserConfigDir()
	if err != nil {
		return "", err
	}
	dir := filepath.Join(configDir, "muyue")

	legacyDir := filepath.Join(homeDir(), ".muyue")
	if _, err := os.Stat(legacyDir); err == nil {
		if _, err := os.Stat(dir); err != nil {
			os.Rename(legacyDir, dir)
		}
	}

	return dir, nil
}

func homeDir() string {
	home, err := os.UserHomeDir()
	if err != nil {
		return "/"
	}
	return home
}

func ConfigPath() (string, error) {
	dir, err := ConfigDir()
	if err != nil {
		return "", err
	}
	return filepath.Join(dir, "config.yaml"), nil
}

func Exists() bool {
	path, err := ConfigPath()
	if err != nil {
		return false
	}
	_, err = os.Stat(path)
	return err == nil
}

func Load() (*MuyueConfig, error) {
	path, err := ConfigPath()
	if err != nil {
		return nil, err
	}

	data, err := os.ReadFile(path)
	if err != nil {
		return nil, fmt.Errorf("reading config: %w", err)
	}

	var cfg MuyueConfig
	if err := yaml.Unmarshal(data, &cfg); err != nil {
		return nil, fmt.Errorf("parsing config: %w", err)
	}

	// Decrypt API keys
	for i := range cfg.AI.Providers {
		if cfg.AI.Providers[i].APIKey != "" {
			decrypted, err := secret.Decrypt(cfg.AI.Providers[i].APIKey)
			if err != nil {
				decrypted = cfg.AI.Providers[i].APIKey
			}
			cfg.AI.Providers[i].APIKey = decrypted
		}
	}

	return &cfg, nil
}

func Save(cfg *MuyueConfig) error {
	dir, err := ConfigDir()
	if err != nil {
		return err
	}

	if err := os.MkdirAll(dir, 0755); err != nil {
		return fmt.Errorf("creating config dir: %w", err)
	}

	// Encrypt API keys before saving
	saveCfg := *cfg
	saveCfg.AI.Providers = make([]AIProvider, len(cfg.AI.Providers))
	for i, p := range cfg.AI.Providers {
		saveCfg.AI.Providers[i] = p
		if p.APIKey != "" && !secret.IsEncrypted(p.APIKey) {
			enc, err := secret.Encrypt(p.APIKey)
			if err == nil {
				saveCfg.AI.Providers[i].APIKey = enc
			}
		}
	}

	path := filepath.Join(dir, "config.yaml")
	data, err := yaml.Marshal(&saveCfg)
	if err != nil {
		return fmt.Errorf("marshaling config: %w", err)
	}

	if err := os.WriteFile(path, data, 0600); err != nil {
		return fmt.Errorf("writing config: %w", err)
	}

	return nil
}

func Default() *MuyueConfig {
	cfg := &MuyueConfig{
		Version: "0.1.0",
		Profile: Profile{
			Name:   "",
			Pseudo: "muyue",
			Languages: []string{},
		},
	}

	cfg.Profile.Preferences.DefaultAI = "minimax"
	cfg.Profile.Preferences.AutoUpdate = true
	cfg.Profile.Preferences.CheckOnStart = true
	cfg.Profile.Preferences.Theme = "charm"
	cfg.Profile.Preferences.Language = "fr"
	cfg.Profile.Preferences.KeyboardLayout = "azerty"

	cfg.AI.Providers = []AIProvider{
		{
			Name:    "minimax",
			Model:   "MiniMax-M2.7",
			BaseURL: "https://api.minimax.io/v1",
			Active:  true,
		},
		{
			Name:    "zai",
			Model:   "glm",
			Active:  false,
		},
		{
			Name:    "anthropic",
			Model:   "claude-sonnet-4-20250514",
			Active:  false,
		},
		{
			Name:    "openai",
			Model:   "gpt-4o",
			BaseURL: "https://api.openai.com/v1",
			Active:  false,
		},
		{
			Name:    "ollama",
			Model:   "llama3",
			BaseURL: "http://localhost:11434/api",
			Active:  false,
		},
	}

	cfg.BMAD.Global = true

	cfg.Terminal.CustomPrompt = true
	cfg.Terminal.PromptTheme = "zerotwo"

	return cfg
}