package handlers

import (
	"Yimaru-Backend/internal/domain"
	"errors"
	personasservice "Yimaru-Backend/internal/services/personas"
	"strconv"
	"strings"

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

type listPersonasData struct {
	Personas   []domain.LmsPersona `json:"personas"`
	TotalCount int64               `json:"total_count"`
	Limit      int                 `json:"limit"`
	Offset     int                 `json:"offset"`
}

// CreatePersona godoc
// @Summary Create LMS persona catalog entry
// @Tags personas
// @Accept json
// @Param body body domain.CreateLmsPersonaInput true "Persona"
// @Success 201 {object} domain.Response
// @Router /api/v1/personas [post]
func (h *Handler) CreatePersona(c *fiber.Ctx) error {
	var req domain.CreateLmsPersonaInput
	if err := c.BodyParser(&req); err != nil {
		return c.Status(fiber.StatusBadRequest).JSON(domain.ErrorResponse{
			Message: "Invalid request body",
			Error:   err.Error(),
		})
	}
	if valErrs, ok := h.validator.Validate(c, req); !ok {
		return c.Status(fiber.StatusBadRequest).JSON(domain.ErrorResponse{
			Message: "Validation failed",
			Error:   firstValidationError(valErrs),
		})
	}
	p, err := h.personaSvc.Create(c.Context(), req)
	if err != nil {
		if errors.Is(err, personasservice.ErrNameRequired) {
			return c.Status(fiber.StatusBadRequest).JSON(domain.ErrorResponse{Message: "Validation failed", Error: err.Error()})
		}
		return c.Status(fiber.StatusInternalServerError).JSON(domain.ErrorResponse{Message: "Failed to create persona", Error: err.Error()})
	}
	return c.Status(fiber.StatusCreated).JSON(domain.Response{
		Message:    "Persona created successfully",
		Data:       p,
		Success:    true,
		StatusCode: fiber.StatusCreated,
	})
}

// ListPersonas godoc
// @Summary List LMS personas (catalog for practice assignment)
// @Tags personas
// @Param active_only query bool false "When true (default), return only active personas" default(true)
// @Param limit query int false "Page size"
// @Param offset query int false "Offset"
// @Router /api/v1/personas [get]
func (h *Handler) ListPersonas(c *fiber.Ctx) error {
	activeOnlyStr := strings.ToLower(strings.TrimSpace(c.Query("active_only", "true")))
	activeOnly := activeOnlyStr != "false"

	limit, err := strconv.Atoi(c.Query("limit", "20"))
	if err != nil {
		return c.Status(fiber.StatusBadRequest).JSON(domain.ErrorResponse{Message: "Invalid limit", Error: err.Error()})
	}
	offset, err := strconv.Atoi(c.Query("offset", "0"))
	if err != nil {
		return c.Status(fiber.StatusBadRequest).JSON(domain.ErrorResponse{Message: "Invalid offset", Error: err.Error()})
	}
	items, total, err := h.personaSvc.List(c.Context(), activeOnly, int32(limit), int32(offset))
	if err != nil {
		return c.Status(fiber.StatusInternalServerError).JSON(domain.ErrorResponse{Message: "Failed to list personas", Error: err.Error()})
	}
	return c.JSON(domain.Response{
		Message: "Personas retrieved successfully",
		Data: listPersonasData{
			Personas:   items,
			TotalCount: total,
			Limit:      limit,
			Offset:     offset,
		},
		Success:    true,
		StatusCode: fiber.StatusOK,
	})
}

// GetPersona godoc
// @Summary Get LMS persona by ID
// @Tags personas
// @Param id path int true "Persona ID"
// @Router /api/v1/personas/{id} [get]
func (h *Handler) GetPersona(c *fiber.Ctx) error {
	id, err := strconv.ParseInt(c.Params("id"), 10, 64)
	if err != nil || id <= 0 {
		msg := ""
		if err != nil {
			msg = err.Error()
		}
		return c.Status(fiber.StatusBadRequest).JSON(domain.ErrorResponse{Message: "Invalid persona id", Error: msg})
	}
	p, err := h.personaSvc.GetByID(c.Context(), id)
	if err != nil {
		if errors.Is(err, domain.ErrPersonaNotFound) {
			return c.Status(fiber.StatusNotFound).JSON(domain.ErrorResponse{Message: "Persona not found", Error: err.Error()})
		}
		return c.Status(fiber.StatusInternalServerError).JSON(domain.ErrorResponse{Message: "Failed to load persona", Error: err.Error()})
	}
	return c.JSON(domain.Response{Message: "Persona retrieved successfully", Data: p, Success: true, StatusCode: fiber.StatusOK})
}

// UpdatePersona godoc
// @Summary Update LMS persona
// @Tags personas
// @Param id path int true "Persona ID"
// @Param body body domain.UpdateLmsPersonaInput true "Fields to update"
// @Router /api/v1/personas/{id} [put]
func (h *Handler) UpdatePersona(c *fiber.Ctx) error {
	id, err := strconv.ParseInt(c.Params("id"), 10, 64)
	if err != nil || id <= 0 {
		msg := ""
		if err != nil {
			msg = err.Error()
		}
		return c.Status(fiber.StatusBadRequest).JSON(domain.ErrorResponse{Message: "Invalid persona id", Error: msg})
	}
	var req domain.UpdateLmsPersonaInput
	if err := c.BodyParser(&req); err != nil {
		return c.Status(fiber.StatusBadRequest).JSON(domain.ErrorResponse{Message: "Invalid request body", Error: err.Error()})
	}
	p, err := h.personaSvc.Update(c.Context(), id, req)
	if err != nil {
		if errors.Is(err, domain.ErrPersonaNotFound) {
			return c.Status(fiber.StatusNotFound).JSON(domain.ErrorResponse{Message: "Persona not found", Error: err.Error()})
		}
		if errors.Is(err, personasservice.ErrNameEmptyUpdate) {
			return c.Status(fiber.StatusBadRequest).JSON(domain.ErrorResponse{Message: "Validation failed", Error: err.Error()})
		}
		return c.Status(fiber.StatusInternalServerError).JSON(domain.ErrorResponse{Message: "Failed to update persona", Error: err.Error()})
	}
	return c.JSON(domain.Response{Message: "Persona updated successfully", Data: p, Success: true, StatusCode: fiber.StatusOK})
}

// DeletePersona godoc
// @Summary Delete LMS persona (practices referencing it will have persona_id cleared)
// @Tags personas
// @Param id path int true "Persona ID"
// @Router /api/v1/personas/{id} [delete]
func (h *Handler) DeletePersona(c *fiber.Ctx) error {
	id, err := strconv.ParseInt(c.Params("id"), 10, 64)
	if err != nil || id <= 0 {
		msg := ""
		if err != nil {
			msg = err.Error()
		}
		return c.Status(fiber.StatusBadRequest).JSON(domain.ErrorResponse{Message: "Invalid persona id", Error: msg})
	}
	if err := h.personaSvc.Delete(c.Context(), id); err != nil {
		return c.Status(fiber.StatusInternalServerError).JSON(domain.ErrorResponse{Message: "Failed to delete persona", Error: err.Error()})
	}
	return c.JSON(domain.Response{Message: "Persona deleted successfully", Success: true, StatusCode: fiber.StatusOK})
}