package api

import (
	"net/url"
	"reflect"
	"regexp"
	"strconv"
	"strings"

	"git.sxidc.com/go-framework/baize/framework/core/infrastructure/logger"
	"git.sxidc.com/go-tools/utils/strutils"
	"git.sxidc.com/go-tools/utils/template"
	"github.com/pkg/errors"
)

type UrlInstruction interface {
	FormUrlInstruction() (string, error)
}

func FormUrlInstruction(instructions ...UrlInstruction) string {
	if instructions == nil || len(instructions) == 0 {
		return ""
	}

	urlInstructions := make([]string, 0)
	for _, instruction := range instructions {
		if instruction == nil {
			continue
		}

		urlInstruction, err := instruction.FormUrlInstruction()
		if err != nil {
			panic(err)
		}

		urlInstructions = append(urlInstructions, urlInstruction)
	}

	if urlInstructions == nil || len(urlInstructions) == 0 {
		return ""
	}

	return "${" + strings.Join(urlInstructions, " ") + "}$"
}

const (
	permUrlInstructionTpl = `perm:"group:{{ .Group }};name:{{ .Name }};{{- if .Description -}}description:{{ .Description }};{{- end -}}{{- if .NeedCheckExpire -}}needCheckExpire;{{- end -}}{{- if .SensitiveWordScene -}}sensitiveWordScene:{{ .SensitiveWordScene }};{{- end -}}"`
)

type PermUrlInstruction struct {
	Group              string
	Name               string
	Description        string
	NeedCheckExpire    bool
	SensitiveWordScene int
}

func (cmd *PermUrlInstruction) check() error {
	if strutils.IsStringEmpty(cmd.Group) {
		return errors.New("没有传递权限组")
	}

	if strutils.IsStringEmpty(cmd.Name) {
		return errors.New("没有传递权限名称")
	}

	return nil
}

func (cmd *PermUrlInstruction) FormUrlInstruction() (string, error) {
	err := cmd.check()
	if err != nil {
		return "", err
	}

	permUrlInstruction, err := template.ParseTemplateStringToString(permUrlInstructionTpl, cmd)
	if err != nil {
		return "", err
	}

	return permUrlInstruction, nil
}

// Perm指令定义

const (
	tagPartSeparator         = ";"
	tagPartKeyValueSeparator = ":"
)

const (
	permTagKey                    = "perm"
	permTagPartGroup              = "group"
	permTagPartName               = "name"
	permTagPartDescription        = "description"
	permTagPartNeedCheckExpire    = "needCheckExpire"
	permTagPartSensitiveWordScene = "sensitiveWordScene"
)

func parseRelativePathPerm(basePath string, relativePathPattern string, method string) (string, *PermissionItem, error) {
	re := regexp.MustCompile(`\$\{(.+)\}\$`)
	matches := re.FindStringSubmatch(relativePathPattern)

	if len(matches) == 0 {
		return relativePathPattern, nil, nil
	}

	relativePath := re.ReplaceAllString(relativePathPattern, "")
	permTag, ok := reflect.StructTag(matches[1]).Lookup(permTagKey)
	if !ok {
		return relativePath, nil, nil
	}

	tagParts := strings.Split(permTag, tagPartSeparator)
	if tagParts == nil || len(tagParts) == 0 {
		return relativePath, nil, nil
	}

	fullPath, err := url.JoinPath(basePath, relativePath)
	if err != nil {
		return "", nil, err
	}

	permissionItem := &PermissionItem{
		Group:              "",
		Name:               "",
		Description:        "",
		Resource:           fullPath,
		Action:             method,
		NeedCheckExpire:    false,
		SensitiveWordScene: 0,
	}

	for _, tagPart := range tagParts {
		tagPartKeyValue := strings.SplitN(strings.TrimSpace(tagPart), tagPartKeyValueSeparator, 2)

		if strutils.IsStringEmpty(tagPartKeyValue[0]) {
			continue
		}

		switch tagPartKeyValue[0] {
		case permTagPartGroup:
			permissionItem.Group = tagPartKeyValue[1]
		case permTagPartName:
			permissionItem.Name = tagPartKeyValue[1]
		case permTagPartDescription:
			permissionItem.Description = tagPartKeyValue[1]
		case permTagPartNeedCheckExpire:
			permissionItem.NeedCheckExpire = true
		case permTagPartSensitiveWordScene:
			scene, err := strconv.Atoi(tagPartKeyValue[1])
			if err != nil {
				return relativePath, nil, err
			}

			if scene < 1 || scene > 4 {
				return relativePath, nil, errors.New("不支持的敏感词场景: " + tagPartKeyValue[1])
			}

			permissionItem.SensitiveWordScene = scene
		default:
			err := errors.New(permTagKey + "不支持的tag: " + tagPartKeyValue[0])
			logger.GetInstance().Error(err)
			continue
		}
	}

	err = permissionItem.check()
	if err != nil {
		return "", nil, err
	}

	return relativePath, permissionItem, nil
}