package jwt

import (
	"errors"
	"fmt"
	jwt "github.com/golang-jwt/jwt/v4"
	"github.com/spf13/cast"
	"github.com/zeromicro/go-zero/rest/token"
	"net/http"
	"time"
)

type Config struct {
	AccessSecret string        `json:",default=ac2d27613e131be6286c0eb17139293d"`
	AccessExpire time.Duration `json:",default=24h"`
}

type TokenBuilder struct {
	config Config
}

func NewTokenBuilder(config Config) *TokenBuilder {
	return &TokenBuilder{config: config}
}

// GenerateToken 生成token
func (b *TokenBuilder) GenerateToken(kvs map[string]any) (string, int64, error) {
	// 创建一个新的 Token
	tok := jwt.New(jwt.SigningMethodHS256)
	// 设置 Token 的声明（Payload）
	claims := tok.Claims.(jwt.MapClaims)
	for k, v := range kvs {
		claims[k] = v
	}
	expiredAt := time.Now().Add(b.config.AccessExpire).Unix()
	claims["exp"] = expiredAt // 设置过期时间

	// 使用密钥签名 Token
	tkStr, err := tok.SignedString([]byte(b.config.AccessSecret))
	return tkStr, expiredAt, err
}

func (b *TokenBuilder) ParseUidFromToken(tokenStr string) (int, int64, error) {
	r := &http.Request{Header: http.Header{}}
	r.Header.Set("Authorization", fmt.Sprintf("Bearer %s", tokenStr))
	parser := token.NewTokenParser()
	tok, err := parser.ParseToken(r, b.config.AccessSecret, "")
	if err != nil {
		return 0, 0, err
	}
	if !tok.Valid {
		return 0, 0, errors.New("token is invalid")
	}
	var userId int
	var expiredAt int64
	if claims, ok := tok.Claims.(jwt.MapClaims); ok {
		if data, ok := claims["data"]; ok {
			userId, _ = cast.ToStringMapInt(data)["id"]
		}
		if exp, ok := claims["exp"]; ok {
			expiredAt = cast.ToInt64(exp)
		}
	}
	return userId, expiredAt, nil
}

// ParseUid 解析出uid
func (b *TokenBuilder) ParseUid(r *http.Request) (int, error) {
	parser := token.NewTokenParser()
	tok, err := parser.ParseToken(r, b.config.AccessSecret, "")
	if err != nil {
		return 0, err
	}
	if !tok.Valid {
		return 0, errors.New("token is invalid")
	}
	if claims, ok := tok.Claims.(jwt.MapClaims); ok {
		if data, ok := claims["data"]; ok {
			uid, _ := cast.ToStringMapInt(data)["id"]
			return uid, nil
		}
	}
	return 0, errors.New("token not exist uid")
}

func ParseUid(r *http.Request, accessSecret string) (int, error) {
	parser := token.NewTokenParser()
	tok, err := parser.ParseToken(r, accessSecret, "")
	if err != nil {
		return 0, err
	}
	if !tok.Valid {
		return 0, errors.New("token is invalid")
	}
	if claims, ok := tok.Claims.(jwt.MapClaims); ok {
		if data, ok := claims["data"]; ok {
			uid, _ := cast.ToStringMapInt(data)["id"]
			return uid, nil
		}
	}
	return 0, errors.New("token not exist uid")
}