package v1

import (
	"net/http"

	"github.com/gin-gonic/gin"

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

// PushSubscriptionHandler handles push notification token registration/removal.
// Reference: Chatwoot PushSubscription controller + P2B M8 spec
type PushSubscriptionHandler struct {
	pushSubscriptionService *service.PushSubscriptionService
}

// NewPushSubscriptionHandler creates a new PushSubscription handler with injected service.
func NewPushSubscriptionHandler(pushSubscriptionService *service.PushSubscriptionService) *PushSubscriptionHandler {
	return &PushSubscriptionHandler{pushSubscriptionService: pushSubscriptionService}
}

// List returns all push tokens for the current user.
// GET /api/v1/push_subscriptions
func (h *PushSubscriptionHandler) List(c *gin.Context) {
	if h.pushSubscriptionService == nil {
		response.AbortWithStatusError(c, http.StatusServiceUnavailable, response.ErrInternal, "Push subscription service not available")
		return
	}
	userID := getUserID(c)

	tokens, err := h.pushSubscriptionService.ListPushTokens(c.Request.Context(), userID)
	if err != nil {
		response.AbortWithStatusError(c, http.StatusInternalServerError, response.ErrInternal, "Failed to fetch push subscriptions")
		return
	}

	response.OK(c, gin.H{"push_subscriptions": tokens})
}

// Create registers a new push token for the current user.
// POST /api/v1/push_subscriptions
func (h *PushSubscriptionHandler) Create(c *gin.Context) {
	if h.pushSubscriptionService == nil {
		response.AbortWithStatusError(c, http.StatusServiceUnavailable, response.ErrInternal, "Push subscription service not available")
		return
	}
	userID := getUserID(c)

	var req struct {
		Token    string `json:"token" binding:"required"`
		Platform string `json:"platform"`
		DeviceID string `json:"device_id"`
		P256DH   string `json:"p256dh"` // Web Push: client ECDH public key
		Auth     string `json:"auth"`   // Web Push: client auth secret
	}
	if err := c.ShouldBindJSON(&req); err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, "Invalid request: token is required")
		return
	}

	token, err := h.pushSubscriptionService.RegisterPushToken(c.Request.Context(), userID, req.Token, req.Platform, req.DeviceID, req.P256DH, req.Auth)
	if err != nil {
		response.AbortWithStatusError(c, http.StatusInternalServerError, response.ErrInternal, "Failed to register push subscription")
		return
	}

	response.Created(c, token)
}

// Delete removes a push token by ID.
// DELETE /api/v1/push_subscriptions/:id
func (h *PushSubscriptionHandler) Delete(c *gin.Context) {
	if h.pushSubscriptionService == nil {
		response.AbortWithStatusError(c, http.StatusServiceUnavailable, response.ErrInternal, "Push subscription service not available")
		return
	}
	id, err := parseUintParam(c, "id")
	if err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, "Invalid push subscription ID")
		return
	}

	if err := h.pushSubscriptionService.RemovePushToken(c.Request.Context(), id); err != nil {
		response.AbortWithStatusError(c, http.StatusInternalServerError, response.ErrInternal, "Failed to remove push subscription")
		return
	}

	response.NoContent(c)
}