package v1

import (
	"net/http"
	"time"

	"github.com/gin-gonic/gin"

	"github.com/gochat/gochat/internal/model"
	"github.com/gochat/gochat/internal/service"
	"github.com/gochat/gochat/pkg/response"
)

type chatwootCustomAttributeDefinitionResponse struct {
	ID                   uint        `json:"id"`
	AttributeDisplayName string      `json:"attribute_display_name"`
	AttributeDisplayType string      `json:"attribute_display_type"`
	AttributeDescription string      `json:"attribute_description"`
	AttributeKey         string      `json:"attribute_key"`
	RegexPattern         string      `json:"regex_pattern"`
	RegexCue             string      `json:"regex_cue"`
	AttributeValues      interface{} `json:"attribute_values"`
	AttributeModel       string      `json:"attribute_model"`
	DefaultValue         interface{} `json:"default_value"`
	CreatedAt            time.Time   `json:"created_at"`
	UpdatedAt            time.Time   `json:"updated_at"`
}

func serializeCustomAttributeDefinition(def *model.CustomAttributeDefinition) chatwootCustomAttributeDefinitionResponse {
	return chatwootCustomAttributeDefinitionResponse{
		ID:                   def.ID,
		AttributeDisplayName: def.AttributeDisplayName,
		AttributeDisplayType: def.AttributeType,
		AttributeDescription: def.Description,
		AttributeKey:         def.AttributeName,
		RegexPattern:         def.RegexPattern,
		RegexCue:             def.RegexCue,
		AttributeValues:      def.AttributeValues,
		AttributeModel:       def.AttributeModel,
		DefaultValue:         def.DefaultValue,
		CreatedAt:            def.CreatedAt,
		UpdatedAt:            def.UpdatedAt,
	}
}

func serializeCustomAttributeDefinitions(defs []model.CustomAttributeDefinition) []chatwootCustomAttributeDefinitionResponse {
	items := make([]chatwootCustomAttributeDefinitionResponse, 0, len(defs))
	for i := range defs {
		items = append(items, serializeCustomAttributeDefinition(&defs[i]))
	}
	return items
}

// CustomAttributeDefinitionHandler handles CRUD for custom attribute definitions.
// Reference: Chatwoot app/controllers/api/v1/accounts/custom_attribute_definitions_controller.rb
type CustomAttributeDefinitionHandler struct {
	svc *service.CustomAttributeDefinitionService
}

// NewCustomAttributeDefinitionHandler creates a new handler with service injection.
func NewCustomAttributeDefinitionHandler(svc *service.CustomAttributeDefinitionService) *CustomAttributeDefinitionHandler {
	return &CustomAttributeDefinitionHandler{svc: svc}
}

// List retrieves all custom attribute definitions for an account.
// GET /api/v1/accounts/:account_id/custom_attribute_definitions
// Optional query param: attribute_model (conversation/contact) to filter by model type.
func (h *CustomAttributeDefinitionHandler) List(c *gin.Context) {
	accountID, err := parseUintParam(c, "account_id")
	if err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, "invalid account_id")
		return
	}

	attributeModel := c.Query("attribute_model")

	defs, _, svcErr := h.svc.List(c.Request.Context(), accountID, attributeModel, 0, 0)
	if svcErr != nil {
		handleServiceError(c, svcErr)
		return
	}

	c.JSON(http.StatusOK, serializeCustomAttributeDefinitions(defs))
}

// Get retrieves a single custom attribute definition by ID.
// GET /api/v1/accounts/:account_id/custom_attribute_definitions/:id
func (h *CustomAttributeDefinitionHandler) Get(c *gin.Context) {
	accountID, err := parseUintParam(c, "account_id")
	if err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, "invalid account_id")
		return
	}

	id, err := parseUintParam(c, "id")
	if err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, "invalid id")
		return
	}

	def, svcErr := h.svc.Get(c.Request.Context(), accountID, id)
	if svcErr != nil {
		handleServiceError(c, svcErr)
		return
	}

	c.JSON(http.StatusOK, serializeCustomAttributeDefinition(def))
}

// Create creates a new custom attribute definition for an account.
// POST /api/v1/accounts/:account_id/custom_attribute_definitions
func (h *CustomAttributeDefinitionHandler) Create(c *gin.Context) {
	accountID, err := parseUintParam(c, "account_id")
	if err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, "invalid account_id")
		return
	}

	var req service.CreateCustomAttributeDefinitionRequest
	if err := bindChatwootPayload(c, "custom_attribute_definition", &req); err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrValidation, err.Error())
		return
	}

	def, svcErr := h.svc.Create(c.Request.Context(), accountID, &req)
	if svcErr != nil {
		handleServiceError(c, svcErr)
		return
	}

	c.JSON(http.StatusOK, serializeCustomAttributeDefinition(def))
}

// Update modifies a custom attribute definition.
// PUT /api/v1/accounts/:account_id/custom_attribute_definitions/:id
func (h *CustomAttributeDefinitionHandler) Update(c *gin.Context) {
	accountID, err := parseUintParam(c, "account_id")
	if err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, "invalid account_id")
		return
	}

	id, err := parseUintParam(c, "id")
	if err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, "invalid id")
		return
	}

	var req service.UpdateCustomAttributeDefinitionRequest
	if err := bindChatwootPayload(c, "custom_attribute_definition", &req); err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrValidation, err.Error())
		return
	}

	def, svcErr := h.svc.Update(c.Request.Context(), accountID, id, &req)
	if svcErr != nil {
		handleServiceError(c, svcErr)
		return
	}

	c.JSON(http.StatusOK, serializeCustomAttributeDefinition(def))
}

// Delete soft-deletes a custom attribute definition.
// DELETE /api/v1/accounts/:account_id/custom_attribute_definitions/:id
func (h *CustomAttributeDefinitionHandler) Delete(c *gin.Context) {
	accountID, err := parseUintParam(c, "account_id")
	if err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, "invalid account_id")
		return
	}

	id, err := parseUintParam(c, "id")
	if err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, "invalid id")
		return
	}

	svcErr := h.svc.Delete(c.Request.Context(), accountID, id)
	if svcErr != nil {
		handleServiceError(c, svcErr)
		return
	}

	response.NoContent(c)
}