package config

import (
	"fmt"
	"io/ioutil"
	"path/filepath"

	"gopkg.in/yaml.v3"
)

// Config 结构体包含测试所需的所有配置项
type Config struct {
	Server ServerConfig `yaml:"server"`
	Client ClientConfig `yaml:"client"`
	Test   TestConfig   `yaml:"test"`
}

// ServerConfig 包含服务器配置
type ServerConfig struct {
	ListenAddr      string `yaml:"listen_addr"`
	Port            int    `yaml:"port"`
	LogFile         string `yaml:"log_file"`
	DevicesNVMe     string `yaml:"devices_nvme"`      // NVMe设备路径
	DevicesHDD      string `yaml:"devices_hdd"`       // HDD设备路径
	CacheInstanceID string `yaml:"cache_instance_id"` // Open-CAS缓存实例ID
	MountPoint      string `yaml:"mount_point"`       // 文件系统挂载点
}

// ClientConfig 包含客户端配置
type ClientConfig struct {
	ServerAddr   string `yaml:"server_addr"`
	LogFile      string `yaml:"log_file"`
	Concurrency  int    `yaml:"concurrency"`
	TimeoutSec   int    `yaml:"timeout_sec"`
	ReportFormat string `yaml:"report_format"` // json, csv, html
}

// TestConfig 包含测试相关配置
type TestConfig struct {
	DataSizeMB            int      `yaml:"data_size_mb"`           // 每次测试的数据量
	VerificationFrequency int      `yaml:"verification_frequency"` // 验证频率
	PowerCutMethod        string   `yaml:"power_cut_method"`       // 模拟断电方法
	TestDuration          int      `yaml:"test_duration"`          // 测试持续时间(分钟)
	BlockSize             int      `yaml:"block_size"`             // 块大小(KB)
	EnabledTests          []string `yaml:"enabled_tests"`          // 启用的测试用例
}

// Load 从指定的文件路径加载配置
func Load(path string) (*Config, error) {
	filename, err := filepath.Abs(path)
	if err != nil {
		return nil, err
	}

	yamlFile, err := ioutil.ReadFile(filename)
	if err != nil {
		return nil, fmt.Errorf("error reading config file: %s", err)
	}

	config := &Config{}
	err = yaml.Unmarshal(yamlFile, config)
	if err != nil {
		return nil, fmt.Errorf("error parsing config file: %s", err)
	}

	// 设置默认值
	if config.Server.Port == 0 {
		config.Server.Port = 8080
	}
	if config.Client.Concurrency == 0 {
		config.Client.Concurrency = 5
	}
	if config.Client.TimeoutSec == 0 {
		config.Client.TimeoutSec = 30
	}
	if config.Test.DataSizeMB == 0 {
		config.Test.DataSizeMB = 100
	}
	if config.Test.BlockSize == 0 {
		config.Test.BlockSize = 4 // 4KB
	}
	if config.Test.TestDuration == 0 {
		config.Test.TestDuration = 60 // 60分钟
	}

	return config, nil
}

// Save 将配置保存到指定路径
func (c *Config) Save(path string) error {
	data, err := yaml.Marshal(c)
	if err != nil {
		return fmt.Errorf("error marshaling config: %s", err)
	}

	err = ioutil.WriteFile(path, data, 0644)
	if err != nil {
		return fmt.Errorf("error writing config file: %s", err)
	}

	return nil
}

// CreateDefaultConfig 创建默认配置文件
func CreateDefaultConfig(path string) error {
	config := &Config{
		Server: ServerConfig{
			ListenAddr:      "0.0.0.0",
			Port:            8080,
			LogFile:         "server.log",
			DevicesNVMe:     "/dev/nvme0n1",
			DevicesHDD:      "/dev/sda",
			CacheInstanceID: "cache1",
			MountPoint:      "/mnt/opencas",
		},
		Client: ClientConfig{
			ServerAddr:   "localhost:8080",
			LogFile:      "client.log",
			Concurrency:  5,
			TimeoutSec:   30,
			ReportFormat: "json",
		},
		Test: TestConfig{
			DataSizeMB:            100,
			VerificationFrequency: 10,
			PowerCutMethod:        "signal", // signal或physical
			TestDuration:          60,
			BlockSize:             4,
			EnabledTests:          []string{"sequential", "random", "mixed", "concurrent", "power_loss", "stability"},
		},
	}

	return config.Save(path)
}