package main

import (
	"flag"
	"fmt"
	"os"
	"reflect"

	"gopkg.in/yaml.v3"
)

// Yaml struct of config
type YamlConfig struct {
	Logger struct {
		File  string `yaml:"file"`
		Level string `yaml:"level"`
	}

	Rest struct {
		Addr string `yaml:"addr"`
		Port uint16 `yaml:"port"`
	}

	Database struct {
		Type     string `yaml:"type"`
		User     string `yaml:"user"`
		Password string `yaml:"password"`
		Host     string `yaml:"host"`
		Port     string `yaml:"port"`
		Name     string `yaml:"name"`
	}
	ParamFileDir string `yaml:"paramfiledir"`
}

var yamlConfig YamlConfig

func ReadConfig(configFile string) {
	yamlFile, err := os.ReadFile(configFile)
	if err != nil {
		fmt.Printf("ioutil.ReadFile %s err %v", configFile, err)
	}
	//	fmt.Println("yamlfile:", string(yamlFile))

	err = yaml.Unmarshal(yamlFile, &yamlConfig)
	if err != nil {
		fmt.Printf("Unmarshal: %v when to struct", err)
	}
}

func GetYamlConfig() *YamlConfig {
	return &yamlConfig
}

//var mapYaml map[string]interface{}

func ReadParamConfig(fileName string) *map[string]interface{} {
	file, err := os.ReadFile(fileName)
	if err != nil {
		fmt.Println("yamlFile.Get err", err)
	}

	mapYaml := make(map[string]interface{})

	var node yaml.Node
	err = yaml.Unmarshal(file, &node)
	if err != nil {
		fmt.Printf("yaml.Unmarshal: %v when to struct", err)
	}
	err = unmarshalNode(&node, &mapYaml)
	if err != nil {
		fmt.Println("Failed to unmarshalNode:", err)
	}

	// var node yaml.Node
	// err = yaml.Unmarshal(file, &node)
	// if err != nil {
	// 	fmt.Printf("yaml.Unmarshal: %v when to struct", err)
	// }

	// err = unmarshalNode(&node, reflect.ValueOf(&mapYaml))
	// if err != nil {
	// 	fmt.Println("Failed to unmarshalNode:", err)
	// }

	err = yaml.Unmarshal(file, &mapYaml)
	if err != nil {
		fmt.Printf("yaml.Unmarshal: %v when to struct", err)
	}
	//	fmt.Println("mapYaml:", mapYaml)

	return &mapYaml
}

func GetAllFile(dir string, s []string) ([]string, error) {
	rd, err := os.ReadDir(dir)
	if err != nil {
		fmt.Println("read dir fail:", err)
		return s, err
	}

	for _, fi := range rd {
		if !fi.IsDir() {
			fullName := dir + "/" + fi.Name()
			s = append(s, fullName)
		}
	}
	return s, nil
}

const defaultConfigFile = "./loadpconf.yaml"

var (
	version   string
	buildTime string
	goVer     string
)

var pfiles []string

func init() {
	cfile := flag.String("c", defaultConfigFile, "config file")
	pfile := flag.String("p", "", "param file")
	pv := flag.Bool("v", false, "print version")
	ph := flag.Bool("h", false, "print help")

	flag.Parse()
	if *pv {
		fmt.Printf("OMC initems version: %s\n%s\n%s\n\n", version, buildTime, goVer)
		os.Exit(0)
	}
	if *ph {
		flag.Usage()
		os.Exit(0)
	}

	ReadConfig(*cfile)

	fmt.Println("pfile:", *pfile)
	if *pfile != "" {
		pfiles = append(pfiles, *pfile)
	} else {
		pfiles, _ = GetAllFile(yamlConfig.ParamFileDir, pfiles)
	}
	fmt.Println("pfiles:", pfiles)
}

func unmarshalNode(node *yaml.Node, out interface{}) error {
	switch node.Kind {
	case yaml.DocumentNode:
		return unmarshalNode(node.Content[0], out)
	case yaml.MappingNode:
		m := nodeToMap(node)
		return unmarshalMap(m, out)
	case yaml.SequenceNode:
		s := nodeToSlice(node)
		return unmarshalSlice(s, out)
	case yaml.ScalarNode:
		return unmarshalScalar(node, out)
	default:
		return fmt.Errorf("unknown node kind: %v", node.Kind)
	}
}

func nodeToMap(node *yaml.Node) map[string]*yaml.Node {
	m := make(map[string]*yaml.Node)
	for i := 0; i < len(node.Content); i += 2 {
		key := node.Content[i].Value
		value := node.Content[i+1]
		m[key] = value
	}
	return m
}

func unmarshalMap(m map[string]*yaml.Node, out interface{}) error {
	data, ok := out.(*map[string]interface{})
	if !ok {
		return fmt.Errorf("out must be a map[string]interface{}")
	}

	*data = make(map[string]interface{})
	for key, value := range m {
		var v interface{}
		err := unmarshalNode(value, &v)
		if err != nil {
			return err
		}
		(*data)[key] = v
	}
	return nil
}

func nodeToSlice(node *yaml.Node) []*yaml.Node {
	return node.Content
}

func unmarshalSlice(s []*yaml.Node, out interface{}) error {
	data, ok := out.(*[]interface{})
	if !ok {
		return fmt.Errorf("out must be a []interface{}")
	}

	*data = make([]interface{}, len(s))
	for i, value := range s {
		var v interface{}
		err := unmarshalNode(value, &v)
		if err != nil {
			return err
		}
		(*data)[i] = v
	}
	return nil
}

func unmarshalScalar(node *yaml.Node, out interface{}) error {
	switch node.Tag {
	case "!!str":
		val := reflect.ValueOf(node.Value)
		val.Elem().Set(reflect.ValueOf(out))
		//*out = node.Value
	case "!!int":
		val := reflect.ValueOf(node.Value)
		val.Elem().Set(reflect.ValueOf(out))
		//*out = node.Value
	case "!!float":
		val := reflect.ValueOf(node.Value)
		val.Elem().Set(reflect.ValueOf(out))
		//*out = node.Value
	case "!!bool":
		val := reflect.ValueOf(node.Value == "true")
		val.Elem().Set(reflect.ValueOf(out))
		//*out = node.Value == "true"
	case "!!null":
		val := reflect.ValueOf(node.Value)
		val.Elem().Set(reflect.ValueOf(out))
		//*out = nil
	default:
		return fmt.Errorf("unknown scalar tag: %v", node.Tag)
	}
	return nil
}

/*
func unmarshalNode(node *yaml.Node, out reflect.Value) error {
	switch node.Kind {
	case yaml.DocumentNode:
		return unmarshalNode(node.Content[0], out)
	case yaml.MappingNode:
		m := nodeToMap(node)
		return unmarshalMap(m, out)
	case yaml.SequenceNode:
		s := nodeToSlice(node)
		return unmarshalSlice(s, out)
	case yaml.ScalarNode:
		return unmarshalScalar(node, out)
	default:
		return fmt.Errorf("unknown node kind: %v", node.Kind)
	}
}

func nodeToMap(node *yaml.Node) map[string]*yaml.Node {
	m := make(map[string]*yaml.Node)
	for i := 0; i < len(node.Content); i += 2 {
		key := node.Content[i].Value
		value := node.Content[i+1]
		m[key] = value
	}
	return m
}

func unmarshalMap(m map[string]*yaml.Node, out reflect.Value) error {
	if out.Kind() != reflect.Ptr || out.IsNil() {
		return fmt.Errorf("out must be a non-nil pointer")
	}

	outType := out.Type().Elem()
	if outType.Kind() != reflect.Map {
		return fmt.Errorf("out must be a pointer to a map")
	}

	mapType := outType.Elem()
	if mapType.Kind() != reflect.Interface && mapType.Kind() != reflect.Map {
		return fmt.Errorf("out must be a pointer to a map of interface{}")
	}

	out.Set(reflect.MakeMap(outType))

	for key, value := range m {
		var v reflect.Value
		if mapType.Kind() == reflect.Interface {
			v = reflect.New(reflect.TypeOf((*interface{})(nil)).Elem())
		} else {
			v = reflect.New(mapType)
		}

		err := unmarshalNode(value, v.Elem())
		if err != nil {
			return err
		}

		out.Elem().SetMapIndex(reflect.ValueOf(key), v.Elem())
	}

	return nil
}

func nodeToSlice(node *yaml.Node) []*yaml.Node {
	return node.Content
}

func unmarshalSlice(s []*yaml.Node, out reflect.Value) error {
	if out.Kind() != reflect.Ptr || out.IsNil() {
		return fmt.Errorf("out must be a non-nil pointer")
	}

	outType := out.Type().Elem()
	if outType.Kind() != reflect.Slice {
		return fmt.Errorf("out must be a pointer to a slice")
	}

	sliceType := outType.Elem()
	if sliceType.Kind() != reflect.Interface && sliceType.Kind() != reflect.Slice {
		return fmt.Errorf("out must be a pointer to a slice of interface{}")
	}

	out.Set(reflect.MakeSlice(outType, len(s), len(s)))

	for i, value := range s {
		var v reflect.Value
		if sliceType.Kind() == reflect.Interface {
			v = reflect.New(reflect.TypeOf((*interface{})(nil)).Elem())
		} else {
			v = reflect.New(sliceType)
		}

		err := unmarshalNode(value, v.Elem())
		if err != nil {
			return err
		}

		out.Elem().Index(i).Set(v.Elem())
	}

	return nil
}

func unmarshalScalar(node *yaml.Node, out reflect.Value) error {
	switch node.Tag {
	case "!!str":
		out.SetString(node.Value)
	case "!!int":
		i, err := strconv.ParseInt(node.Value, 10, 64)
		if err != nil {
			return err
		}
		out.SetInt(i)
	case "!!float":
		f, err := strconv.ParseFloat(node.Value, 64)
		if err != nil {
			return err
		}
		out.SetFloat(f)
	case "!!bool":
		b, err := strconv.ParseBool(node.Value)
		if err != nil {
			return err
		}
		out.SetBool(b)
	case "!!null":
		out.Set(reflect.Zero(out.Type()))
	default:
		return fmt.Errorf("unknown scalar tag: %v", node.Tag)
	}
	return nil
}
*/