package v1

import (
	"net/http"
	"strings"

	"github.com/gin-gonic/gin"

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

// IntegrationHookHandler handles IntegrationHook CRUD + ProcessEvent endpoints.
// Reference: Chatwoot Integrations::HooksController + AppsController
type IntegrationHookHandler struct {
	svc *service.IntegrationHookService
}

// NewIntegrationHookHandler creates a new IntegrationHookHandler.
func NewIntegrationHookHandler(svc *service.IntegrationHookService) *IntegrationHookHandler {
	return &IntegrationHookHandler{svc: svc}
}

// --- Integration Apps (catalog) ---

// ListApps retrieves all available integration apps.
// GET /api/v1/accounts/:account_id/integrations/apps
func (h *IntegrationHookHandler) ListApps(c *gin.Context) {
	if !h.svc.Ready() {
		response.AbortWithStatusError(c, http.StatusUnprocessableEntity, response.ErrInternal, "failed to list integration apps")
		return
	}

	apps, err := h.svc.ListApps(c.Request.Context())
	if err != nil {
		handleServiceError(c, err)
		return
	}
	response.OK(c, apps)
}

// GetApp retrieves a single integration app by ID.
// GET /api/v1/accounts/:account_id/integrations/apps/:id
func (h *IntegrationHookHandler) GetApp(c *gin.Context) {
	id, err := parseUintParam(c, "id")
	if err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, "invalid id")
		return
	}

	app, svcErr := h.svc.GetApp(c.Request.Context(), id)
	if svcErr != nil {
		handleServiceError(c, svcErr)
		return
	}
	response.OK(c, app)
}

// --- Integration Hooks CRUD ---

// ListHooks retrieves all integration hooks for an account, paginated.
// GET /api/v1/accounts/:account_id/integrations/hooks
func (h *IntegrationHookHandler) ListHooks(c *gin.Context) {
	accountID := getAccountID(c)
	if accountID == 0 {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, "invalid account_id")
		return
	}

	page := pagination.Parse(c)
	hooks, total, svcErr := h.svc.List(c.Request.Context(), accountID, page.Offset, page.PerPage)
	if svcErr != nil {
		handleServiceError(c, svcErr)
		return
	}
	response.OKWithMeta(c, hooks, page.Page, page.PerPage, total)
}

// GetHook retrieves a single integration hook by ID.
// GET /api/v1/accounts/:account_id/integrations/hooks/:id
func (h *IntegrationHookHandler) GetHook(c *gin.Context) {
	id, err := parseUintParam(c, "id")
	if err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, "invalid hook id")
		return
	}

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

// CreateHook creates a new integration hook.
// POST /api/v1/accounts/:account_id/integrations/hooks
func (h *IntegrationHookHandler) CreateHook(c *gin.Context) {
	accountID := getAccountID(c)
	if accountID == 0 {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, "invalid account_id")
		return
	}

	// Chatwoot: params.require(:hook) → {"hook": {...}}
	var wrapper struct {
		Hook service.CreateHookRequest `json:"hook"`
	}
	if err := c.ShouldBindJSON(&wrapper); err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, err.Error())
		return
	}
	req := wrapper.Hook

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

// UpdateHook updates an existing integration hook.
// PUT /api/v1/accounts/:account_id/integrations/hooks/:id
func (h *IntegrationHookHandler) UpdateHook(c *gin.Context) {
	id, err := parseUintParam(c, "id")
	if err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, "invalid hook id")
		return
	}

	// Chatwoot: params.require(:hook) → {"hook": {...}}
	var wrapper struct {
		Hook service.UpdateHookRequest `json:"hook"`
	}
	if err := c.ShouldBindJSON(&wrapper); err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, err.Error())
		return
	}
	req := wrapper.Hook

	hook, svcErr := h.svc.Update(c.Request.Context(), id, req)
	if svcErr != nil {
		handleServiceError(c, svcErr)
		return
	}
	response.OK(c, hook)
}

// DeleteHook deletes an integration hook.
// DELETE /api/v1/accounts/:account_id/integrations/hooks/:id
func (h *IntegrationHookHandler) DeleteHook(c *gin.Context) {
	id, err := parseUintParam(c, "id")
	if err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, "invalid hook id")
		return
	}

	if svcErr := h.svc.Delete(c.Request.Context(), id); svcErr != nil {
		handleServiceError(c, svcErr)
		return
	}
	response.OK(c, gin.H{"id": id})
}

// ProcessHookEvent processes an incoming event for a hook.
// POST /api/v1/accounts/:account_id/integrations/hooks/:id/process_event
func (h *IntegrationHookHandler) ProcessHookEvent(c *gin.Context) {
	id, err := parseUintParam(c, "id")
	if err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, "invalid hook id")
		return
	}

	var eventData map[string]interface{}
	if err := c.ShouldBindJSON(&eventData); err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, err.Error())
		return
	}

	if svcErr := h.svc.ProcessEvent(c.Request.Context(), id, eventData); svcErr != nil {
		if strings.Contains(strings.ToLower(svcErr.Error()), "not found") {
			response.AbortWithStatusError(c, http.StatusNotFound, response.ErrNotFound, svcErr.Error())
			return
		}
		response.AbortWithStatusError(c, http.StatusUnprocessableEntity, response.ErrInternal, svcErr.Error())
		return
	}
	response.OK(c, gin.H{"message": "event processed"})
}

// RegisterIntegrationHookRoutes registers integration hook routes on a router group.
func RegisterIntegrationHookRoutes(g *gin.RouterGroup, h *IntegrationHookHandler) {
	// Integration apps catalog
	apps := g.Group("/apps")
	{
		apps.GET("/", h.ListApps)
		apps.GET("/:id", h.GetApp)
	}

	// Integration hooks CRUD + process event
	hooks := g.Group("/hooks")
	{
		hooks.GET("/", h.ListHooks)
		hooks.GET("/:id", h.GetHook)
		hooks.POST("/", h.CreateHook)
		hooks.PUT("/:id", h.UpdateHook)
		hooks.DELETE("/:id", h.DeleteHook)
		hooks.POST("/:id/process_event", h.ProcessHookEvent)
	}
}