package config

import (
	"encoding/json"
	"fmt"
	"os"

	"skillmgr/internal/types"
)

// LoadInstallConfig 加载安装配置
func LoadInstallConfig() (*types.InstallConfig, error) {
	path, err := GetInstallConfigPath()
	if err != nil {
		return nil, err
	}

	if _, err := os.Stat(path); os.IsNotExist(err) {
		return &types.InstallConfig{
			Installations: []types.InstallRecord{},
		}, nil
	}

	data, err := os.ReadFile(path)
	if err != nil {
		return nil, err
	}

	var cfg types.InstallConfig
	if err := json.Unmarshal(data, &cfg); err != nil {
		return nil, fmt.Errorf("解析 install.json 失败: %w（请检查 JSON 格式）", err)
	}

	return &cfg, nil
}

// SaveInstallConfig 保存安装配置
func SaveInstallConfig(cfg *types.InstallConfig) error {
	path, err := GetInstallConfigPath()
	if err != nil {
		return err
	}

	data, err := json.MarshalIndent(cfg, "", "  ")
	if err != nil {
		return err
	}

	return os.WriteFile(path, data, 0644)
}

// AddInstallRecord 添加安装记录
func AddInstallRecord(record types.InstallRecord) error {
	cfg, err := LoadInstallConfig()
	if err != nil {
		return err
	}

	cfg.Installations = append(cfg.Installations, record)
	return SaveInstallConfig(cfg)
}

// RemoveInstallRecord 移除安装记录
func RemoveInstallRecord(itemType types.ItemType, name string, platform types.Platform, scope types.Scope) error {
	cfg, err := LoadInstallConfig()
	if err != nil {
		return err
	}

	for i, r := range cfg.Installations {
		if r.Type == itemType && r.Name == name && r.Platform == platform && r.Scope == scope {
			cfg.Installations = append(cfg.Installations[:i], cfg.Installations[i+1:]...)
			return SaveInstallConfig(cfg)
		}
	}

	return nil
}

// FindInstallRecord 查找安装记录
func FindInstallRecord(itemType types.ItemType, name string, platform types.Platform, scope types.Scope) (*types.InstallRecord, error) {
	cfg, err := LoadInstallConfig()
	if err != nil {
		return nil, err
	}

	for _, r := range cfg.Installations {
		if r.Type == itemType && r.Name == name && r.Platform == platform && r.Scope == scope {
			return &r, nil
		}
	}

	return nil, nil
}

// UpdateInstallRecord 更新安装记录
func UpdateInstallRecord(record types.InstallRecord) error {
	cfg, err := LoadInstallConfig()
	if err != nil {
		return err
	}

	for i, r := range cfg.Installations {
		if r.Type == record.Type && r.Name == record.Name &&
			r.Platform == record.Platform && r.Scope == record.Scope {
			cfg.Installations[i] = record
			return SaveInstallConfig(cfg)
		}
	}

	return nil
}

// CleanOrphanRecords 清理孤立记录（安装路径不存在）
func CleanOrphanRecords() ([]types.InstallRecord, error) {
	cfg, err := LoadInstallConfig()
	if err != nil {
		return nil, err
	}

	// 预分配切片容量，减少内存分配次数
	cleaned := make([]types.InstallRecord, 0, len(cfg.Installations)/2)
	valid := make([]types.InstallRecord, 0, len(cfg.Installations))

	for _, r := range cfg.Installations {
		if _, err := os.Stat(r.InstallPath); os.IsNotExist(err) {
			cleaned = append(cleaned, r)
		} else {
			valid = append(valid, r)
		}
	}

	if len(cleaned) > 0 {
		cfg.Installations = valid
		if err := SaveInstallConfig(cfg); err != nil {
			return nil, err
		}
	}

	return cleaned, nil
}