package handler

import (
	"apskel-pos-be/internal/appcontext"
	"apskel-pos-be/internal/constants"
	"apskel-pos-be/internal/contract"
	"apskel-pos-be/internal/logger"
	"apskel-pos-be/internal/service"
	"apskel-pos-be/internal/util"
	"apskel-pos-be/internal/validator"

	"github.com/gin-gonic/gin"
	"github.com/google/uuid"
)

type NotificationHandler struct {
	notificationService   service.NotificationService
	notificationValidator validator.NotificationValidator
}

func NewNotificationHandler(
	notificationService service.NotificationService,
	notificationValidator validator.NotificationValidator,
) *NotificationHandler {
	return &NotificationHandler{
		notificationService:   notificationService,
		notificationValidator: notificationValidator,
	}
}

// Send godoc
// POST /api/v1/notifications/send
// Sends a notification to specific users.
func (h *NotificationHandler) Send(c *gin.Context) {
	ctx := c.Request.Context()
	contextInfo := appcontext.FromGinContext(ctx)

	var req contract.SendNotificationRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		logger.FromContext(ctx).WithError(err).Error("NotificationHandler::Send -> request binding failed")
		validationErr := contract.NewResponseError(constants.MissingFieldErrorCode, constants.RequestEntity, err.Error())
		util.HandleResponse(c.Writer, c.Request, contract.BuildErrorResponse([]*contract.ResponseError{validationErr}), "NotificationHandler::Send")
		return
	}

	if validationErr, errCode := h.notificationValidator.ValidateSendRequest(&req); validationErr != nil {
		respErr := contract.NewResponseError(errCode, constants.RequestEntity, validationErr.Error())
		util.HandleResponse(c.Writer, c.Request, contract.BuildErrorResponse([]*contract.ResponseError{respErr}), "NotificationHandler::Send")
		return
	}

	resp := h.notificationService.Send(ctx, &req, contextInfo.UserID)
	if resp.HasErrors() {
		logger.FromContext(ctx).WithError(resp.GetErrors()[0]).Error("NotificationHandler::Send -> service error")
	}

	util.HandleResponse(c.Writer, c.Request, resp, "NotificationHandler::Send")
}

// Broadcast godoc
// POST /api/v1/notifications/broadcast
// Sends a notification to all active users in the caller's organization.
func (h *NotificationHandler) Broadcast(c *gin.Context) {
	ctx := c.Request.Context()
	contextInfo := appcontext.FromGinContext(ctx)

	var req contract.BroadcastNotificationRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		logger.FromContext(ctx).WithError(err).Error("NotificationHandler::Broadcast -> request binding failed")
		validationErr := contract.NewResponseError(constants.MissingFieldErrorCode, constants.RequestEntity, err.Error())
		util.HandleResponse(c.Writer, c.Request, contract.BuildErrorResponse([]*contract.ResponseError{validationErr}), "NotificationHandler::Broadcast")
		return
	}

	if validationErr, errCode := h.notificationValidator.ValidateBroadcastRequest(&req); validationErr != nil {
		respErr := contract.NewResponseError(errCode, constants.RequestEntity, validationErr.Error())
		util.HandleResponse(c.Writer, c.Request, contract.BuildErrorResponse([]*contract.ResponseError{respErr}), "NotificationHandler::Broadcast")
		return
	}

	resp := h.notificationService.Broadcast(ctx, &req, contextInfo.OrganizationID, contextInfo.UserID)
	if resp.HasErrors() {
		logger.FromContext(ctx).WithError(resp.GetErrors()[0]).Error("NotificationHandler::Broadcast -> service error")
	}

	util.HandleResponse(c.Writer, c.Request, resp, "NotificationHandler::Broadcast")
}

// List godoc
// GET /api/v1/notifications
// Returns paginated notifications for the authenticated user.
func (h *NotificationHandler) List(c *gin.Context) {
	ctx := c.Request.Context()
	contextInfo := appcontext.FromGinContext(ctx)

	req := contract.ListNotificationsRequest{
		Page:  1,
		Limit: 20,
	}

	if err := c.ShouldBindQuery(&req); err != nil {
		logger.FromContext(ctx).WithError(err).Error("NotificationHandler::List -> query binding failed")
		validationErr := contract.NewResponseError(constants.MissingFieldErrorCode, constants.RequestEntity, err.Error())
		util.HandleResponse(c.Writer, c.Request, contract.BuildErrorResponse([]*contract.ResponseError{validationErr}), "NotificationHandler::List")
		return
	}

	if validationErr, errCode := h.notificationValidator.ValidateListRequest(&req); validationErr != nil {
		respErr := contract.NewResponseError(errCode, constants.RequestEntity, validationErr.Error())
		util.HandleResponse(c.Writer, c.Request, contract.BuildErrorResponse([]*contract.ResponseError{respErr}), "NotificationHandler::List")
		return
	}

	resp := h.notificationService.ListForUser(ctx, &req, contextInfo.UserID)
	util.HandleResponse(c.Writer, c.Request, resp, "NotificationHandler::List")
}

// GetByID godoc
// GET /api/v1/notifications/:id
func (h *NotificationHandler) GetByID(c *gin.Context) {
	ctx := c.Request.Context()

	idStr := c.Param("id")
	id, err := uuid.Parse(idStr)
	if err != nil {
		logger.FromContext(ctx).WithError(err).Error("NotificationHandler::GetByID -> invalid notification ID")
		validationErr := contract.NewResponseError(constants.MalformedFieldErrorCode, constants.RequestEntity, "Invalid notification ID")
		util.HandleResponse(c.Writer, c.Request, contract.BuildErrorResponse([]*contract.ResponseError{validationErr}), "NotificationHandler::GetByID")
		return
	}

	resp := h.notificationService.GetByID(ctx, id)
	util.HandleResponse(c.Writer, c.Request, resp, "NotificationHandler::GetByID")
}

// MarkAsRead godoc
// PUT /api/v1/notifications/:id/read
func (h *NotificationHandler) MarkAsRead(c *gin.Context) {
	ctx := c.Request.Context()
	contextInfo := appcontext.FromGinContext(ctx)

	idStr := c.Param("id")
	receiverID, err := uuid.Parse(idStr)
	if err != nil {
		logger.FromContext(ctx).WithError(err).Error("NotificationHandler::MarkAsRead -> invalid receiver ID")
		validationErr := contract.NewResponseError(constants.MalformedFieldErrorCode, constants.RequestEntity, "Invalid notification receiver ID")
		util.HandleResponse(c.Writer, c.Request, contract.BuildErrorResponse([]*contract.ResponseError{validationErr}), "NotificationHandler::MarkAsRead")
		return
	}

	resp := h.notificationService.MarkAsRead(ctx, receiverID, contextInfo.UserID)
	if resp.HasErrors() {
		logger.FromContext(ctx).WithError(resp.GetErrors()[0]).Error("NotificationHandler::MarkAsRead -> service error")
	}

	util.HandleResponse(c.Writer, c.Request, resp, "NotificationHandler::MarkAsRead")
}

// MarkAllAsRead godoc
// PUT /api/v1/notifications/read-all
func (h *NotificationHandler) MarkAllAsRead(c *gin.Context) {
	ctx := c.Request.Context()
	contextInfo := appcontext.FromGinContext(ctx)

	resp := h.notificationService.MarkAllAsRead(ctx, contextInfo.UserID)
	util.HandleResponse(c.Writer, c.Request, resp, "NotificationHandler::MarkAllAsRead")
}

// Delete godoc
// DELETE /api/v1/notifications/:id
func (h *NotificationHandler) Delete(c *gin.Context) {
	ctx := c.Request.Context()
	contextInfo := appcontext.FromGinContext(ctx)

	idStr := c.Param("id")
	receiverID, err := uuid.Parse(idStr)
	if err != nil {
		logger.FromContext(ctx).WithError(err).Error("NotificationHandler::Delete -> invalid receiver ID")
		validationErr := contract.NewResponseError(constants.MalformedFieldErrorCode, constants.RequestEntity, "Invalid notification receiver ID")
		util.HandleResponse(c.Writer, c.Request, contract.BuildErrorResponse([]*contract.ResponseError{validationErr}), "NotificationHandler::Delete")
		return
	}

	resp := h.notificationService.DeleteForUser(ctx, receiverID, contextInfo.UserID)
	if resp.HasErrors() {
		logger.FromContext(ctx).WithError(resp.GetErrors()[0]).Error("NotificationHandler::Delete -> service error")
	}

	util.HandleResponse(c.Writer, c.Request, resp, "NotificationHandler::Delete")
}