package handlers

import (
	"Yimaru-Backend/internal/domain"
	"Yimaru-Backend/internal/services/authentication"
	"errors"
	"strconv"

	"github.com/gofiber/fiber/v2"
)

// CreateAssessmentQuestion godoc
// @Summary Create assessment question
// @Description Creates a new question for the initial knowledge assessment
// @Tags assessment
// @Accept json
// @Produce json
// @Param question body domain.AssessmentQuestion true "Assessment question payload"
// @Success 201 {object} domain.Response{data=domain.AssessmentQuestion}
// @Failure 400 {object} domain.ErrorResponse
// @Failure 500 {object} domain.ErrorResponse
// @Router /api/v1/assessment/questions [post]
func (h *Handler) CreateAssessmentQuestion(c *fiber.Ctx) error {
	var req domain.AssessmentQuestion
	if err := c.BodyParser(&req); err != nil {
		return c.Status(fiber.StatusBadRequest).JSON(domain.ErrorResponse{
			Message: "Invalid request body",
			Error:   err.Error(),
		})
	}

	question, err := h.assessmentSvc.CreateAssessmentQuestion(c.Context(), req)
	if err != nil {
		return c.Status(fiber.StatusBadRequest).JSON(domain.ErrorResponse{
			Message: "Failed to create assessment question",
			Error:   err.Error(),
		})
	}

	return c.Status(fiber.StatusCreated).JSON(domain.Response{
		Message: "Assessment question created successfully",
		Data:    question,
	})
}

// GetActiveAssessmentQuestions godoc
// @Summary Get active initial assessment questions
// @Description Returns all active questions used for initial knowledge assessment
// @Tags assessment
// @Accept json
// @Produce json
// @Success 200 {object} domain.Response{data=[]domain.AssessmentQuestion}
// @Failure 500 {object} domain.ErrorResponse
// @Router /api/v1/assessment/questions [get]
func (h *Handler) GetActiveAssessmentQuestions(c *fiber.Ctx) error {
	questions, err := h.assessmentSvc.GetActiveAssessmentQuestions(c.Context())
	if err != nil {
		return c.Status(fiber.StatusInternalServerError).JSON(domain.ErrorResponse{
			Message: "Failed to fetch assessment questions",
			Error:   err.Error(),
		})
	}

	return c.Status(fiber.StatusOK).JSON(domain.Response{
		Message: "Assessment questions fetched successfully",
		Data:    questions,
	})
}

// SubmitAssessment godoc
// @Summary Submit initial knowledge assessment
// @Description Evaluates user responses, calculates knowledge level, updates user profile, and sends notification
// @Tags assessment
// @Accept json
// @Produce json
// @Param user_id path int true "User ID"
// @Param payload body domain.SubmitAssessmentReq true "Assessment responses"
// @Success 200 {object} domain.Response
// @Failure 400 {object} domain.ErrorResponse
// @Failure 404 {object} domain.ErrorResponse
// @Failure 500 {object} domain.ErrorResponse
// @Router /api/v1/{tenant_slug}/assessment/submit [post]
func (h *Handler) SubmitAssessment(c *fiber.Ctx) error {

	// User ID (from auth context or path, depending on your setup)
	userIDStr, ok := c.Locals("user_id").(string)
	if !ok || userIDStr == "" {
		return c.Status(fiber.StatusBadRequest).JSON(domain.ErrorResponse{
			Message: "Invalid user context",
			Error:   "User ID not found in request context",
		})
	}

	userID, err := strconv.ParseInt(userIDStr, 10, 64)
	if err != nil || userID <= 0 {
		return c.Status(fiber.StatusBadRequest).JSON(domain.ErrorResponse{
			Message: "Invalid user ID",
			Error:   "User ID must be a positive integer",
		})
	}

	// Parse request body
	var req domain.SubmitAssessmentReq
	if err := c.BodyParser(&req); err != nil {
		return c.Status(fiber.StatusBadRequest).JSON(domain.ErrorResponse{
			Message: "Invalid request body",
			Error:   err.Error(),
		})
	}

	if len(req.Answers) == 0 {
		return c.Status(fiber.StatusBadRequest).JSON(domain.ErrorResponse{
			Message: "No answers submitted",
			Error:   "Assessment answers cannot be empty",
		})
	}

	// Submit assessment
	attempt, err := h.assessmentSvc.SubmitAssessment(
		c.Context(),
		userID,
		req.Answers,
	)
	if err != nil {
		if errors.Is(err, authentication.ErrUserNotFound) {
			return c.Status(fiber.StatusNotFound).JSON(domain.ErrorResponse{
				Message: "User not found",
				Error:   err.Error(),
			})
		}

		return c.Status(fiber.StatusInternalServerError).JSON(domain.ErrorResponse{
			Message: "Failed to submit assessment",
			Error:   err.Error(),
		})
	}

	return c.Status(fiber.StatusOK).JSON(domain.Response{
		Message: "Assessment submitted successfully",
		Data:    attempt,
	})
}