package service_auth

import (
	"context"
	"net/url"
	"nixcn-cms/data"
	"nixcn-cms/internal/authcode"
	"nixcn-cms/internal/exception"
	"nixcn-cms/service/shared"

	"github.com/google/uuid"
	"gorm.io/gorm"
)

type RedirectData struct {
	ClientId    string `json:"client_id"`
	RedirectUri string `json:"redirect_uri"`
	State       string `json:"state"`
	Code        string `json:"code"`
}

type RedirectPayload struct {
	Context context.Context
	Data    *RedirectData
}

type RedirectResult struct {
	Common shared.CommonResult
	Data   string
}

func (self *AuthServiceImpl) Redirect(payload *RedirectPayload) (result *RedirectResult) {
	var err error

	authCode, ok := authcode.VerifyAuthCode(payload.Context, payload.Data.Code)
	if !ok {
		exception := new(exception.Builder).
			SetStatus(exception.StatusUser).
			SetService(exception.ServiceAuth).
			SetEndpoint(exception.EndpointAuthServiceRedirect).
			SetType(exception.TypeSpecific).
			SetOriginal(exception.AuthRedirectTokenInvalid).
			Throw(payload.Context)

		result = &RedirectResult{
			Common: shared.CommonResult{
				HttpCode:  403,
				Exception: exception,
			},
		}

		return
	}

	userData, err := new(data.User).
		GetByEmail(payload.Context, &authCode.Email)
	if err != nil {
		if err == gorm.ErrRecordNotFound {
			userData.UUID = uuid.New()
			userData.UserId = uuid.New()
			userData.Email = authCode.Email
			userData.Username = userData.UserId.String()
			userData.PermissionLevel = 10
			if err := userData.Create(payload.Context); err != nil {
				exception := new(exception.Builder).
					SetStatus(exception.StatusServer).
					SetService(exception.ServiceAuth).
					SetEndpoint(exception.EndpointAuthServiceRedirect).
					SetType(exception.TypeCommon).
					SetOriginal(exception.CommonErrorInternal).
					SetError(err).
					Throw(payload.Context)

				result = &RedirectResult{
					Common: shared.CommonResult{
						HttpCode:  500,
						Exception: exception,
					},
				}

				return
			}
		} else {
			exception := new(exception.Builder).
				SetStatus(exception.StatusServer).
				SetService(exception.ServiceAuth).
				SetEndpoint(exception.EndpointAuthServiceRedirect).
				SetType(exception.TypeCommon).
				SetOriginal(exception.CommonErrorInternal).
				SetError(err).
				Throw(payload.Context)

			result = &RedirectResult{
				Common: shared.CommonResult{
					HttpCode:  500,
					Exception: exception,
				},
			}

			return
		}
	}

	clientData := new(data.Client)
	client, err := clientData.GetClientByClientId(payload.Context, payload.Data.ClientId)
	if err != nil {
		exception := new(exception.Builder).
			SetStatus(exception.StatusUser).
			SetService(exception.ServiceAuth).
			SetEndpoint(exception.EndpointAuthServiceRedirect).
			SetType(exception.TypeSpecific).
			SetOriginal(exception.AuthRedirectClientNotFound).
			SetError(err).
			Throw(payload.Context)

		result = &RedirectResult{
			Common: shared.CommonResult{
				HttpCode:  400,
				Exception: exception,
			},
		}

		return
	}

	if err = client.ValidateRedirectURI(payload.Data.RedirectUri); err != nil {
		exception := new(exception.Builder).
			SetStatus(exception.StatusUser).
			SetService(exception.ServiceAuth).
			SetEndpoint(exception.EndpointAuthServiceRedirect).
			SetType(exception.TypeSpecific).
			SetOriginal(exception.AuthRedirectUriMismatch).
			SetError(err).
			Throw(payload.Context)

		result = &RedirectResult{
			Common: shared.CommonResult{
				HttpCode:  400,
				Exception: exception,
			},
		}

		return
	}

	newCode, err := authcode.NewAuthCode(payload.Context, payload.Data.ClientId, authCode.Email)
	if err != nil {
		exception := new(exception.Builder).
			SetStatus(exception.StatusServer).
			SetService(exception.ServiceAuth).
			SetEndpoint(exception.EndpointAuthServiceRedirect).
			SetType(exception.TypeCommon).
			SetOriginal(exception.CommonErrorInternal).
			SetError(err).
			Throw(payload.Context)

		result = &RedirectResult{
			Common: shared.CommonResult{
				HttpCode:  500,
				Exception: exception,
			},
		}

		return
	}

	targetUrl, err := url.Parse(payload.Data.RedirectUri)
	if err != nil {
		exception := new(exception.Builder).
			SetStatus(exception.StatusUser).
			SetService(exception.ServiceAuth).
			SetEndpoint(exception.EndpointAuthServiceRedirect).
			SetType(exception.TypeSpecific).
			SetOriginal(exception.AuthRedirectInvalidUri).
			SetError(err).
			Throw(payload.Context)

		result = &RedirectResult{
			Common: shared.CommonResult{
				HttpCode:  400,
				Exception: exception,
			},
		}

		return
	}

	query := targetUrl.Query()
	query.Set("code", newCode)
	if payload.Data.State != "" {
		query.Set("state", payload.Data.State)
	}
	targetUrl.RawQuery = query.Encode()

	result = &RedirectResult{
		Common: shared.CommonResult{
			HttpCode: 200,
			Exception: new(exception.Builder).
				SetStatus(exception.StatusSuccess).
				SetService(exception.ServiceAuth).
				SetEndpoint(exception.EndpointAuthServiceRedirect).
				SetType(exception.TypeCommon).
				SetOriginal(exception.CommonSuccess).
				Throw(payload.Context),
		},
		Data: targetUrl.String(),
	}

	return
}