package handlers

import (
	"fmt"
	"net/http"

	"github.com/gin-gonic/gin"
	"github.com/google/uuid"
	"gorm.io/gorm"

	"github.com/Wikid82/CaddyProxyManagerPlus/backend/internal/caddy"
	"github.com/Wikid82/CaddyProxyManagerPlus/backend/internal/models"
	"github.com/Wikid82/CaddyProxyManagerPlus/backend/internal/services"
)

// ProxyHostHandler handles CRUD operations for proxy hosts.
type ProxyHostHandler struct {
	service             *services.ProxyHostService
	caddyManager        *caddy.Manager
	notificationService *services.NotificationService
}

// NewProxyHostHandler creates a new proxy host handler.
func NewProxyHostHandler(db *gorm.DB, caddyManager *caddy.Manager, ns *services.NotificationService) *ProxyHostHandler {
	return &ProxyHostHandler{
		service:             services.NewProxyHostService(db),
		caddyManager:        caddyManager,
		notificationService: ns,
	}
}

// RegisterRoutes registers proxy host routes.
func (h *ProxyHostHandler) RegisterRoutes(router *gin.RouterGroup) {
	router.GET("/proxy-hosts", h.List)
	router.POST("/proxy-hosts", h.Create)
	router.GET("/proxy-hosts/:uuid", h.Get)
	router.PUT("/proxy-hosts/:uuid", h.Update)
	router.DELETE("/proxy-hosts/:uuid", h.Delete)
	router.POST("/proxy-hosts/test", h.TestConnection)
}

// List retrieves all proxy hosts.
func (h *ProxyHostHandler) List(c *gin.Context) {
	hosts, err := h.service.List()
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, hosts)
}

// Create creates a new proxy host.
func (h *ProxyHostHandler) Create(c *gin.Context) {
	var host models.ProxyHost
	if err := c.ShouldBindJSON(&host); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}

	host.UUID = uuid.NewString()

	// Assign UUIDs to locations
	for i := range host.Locations {
		host.Locations[i].UUID = uuid.NewString()
	}

	if err := h.service.Create(&host); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}

	if h.caddyManager != nil {
		if err := h.caddyManager.ApplyConfig(c.Request.Context()); err != nil {
			// Rollback: delete the created host if config application fails
			fmt.Printf("Error applying config: %v\n", err) // Log to stdout
			if deleteErr := h.service.Delete(host.ID); deleteErr != nil {
				fmt.Printf("Critical: Failed to rollback host %d: %v\n", host.ID, deleteErr)
			}
			c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to apply configuration: " + err.Error()})
			return
		}
	}

	// Send Notification
	if h.notificationService != nil {
		h.notificationService.SendExternal(
			"proxy_host",
			"Proxy Host Created",
			fmt.Sprintf("Proxy Host %s (%s) created", host.Name, host.DomainNames),
			map[string]interface{}{
				"Name":    host.Name,
				"Domains": host.DomainNames,
				"Action":  "created",
			},
		)
	}

	c.JSON(http.StatusCreated, host)
}

// Get retrieves a proxy host by UUID.
func (h *ProxyHostHandler) Get(c *gin.Context) {
	uuid := c.Param("uuid")

	host, err := h.service.GetByUUID(uuid)
	if err != nil {
		c.JSON(http.StatusNotFound, gin.H{"error": "proxy host not found"})
		return
	}

	c.JSON(http.StatusOK, host)
}

// Update updates an existing proxy host.
func (h *ProxyHostHandler) Update(c *gin.Context) {
	uuid := c.Param("uuid")

	host, err := h.service.GetByUUID(uuid)
	if err != nil {
		c.JSON(http.StatusNotFound, gin.H{"error": "proxy host not found"})
		return
	}

	if err := c.ShouldBindJSON(host); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}

	if err := h.service.Update(host); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}

	if h.caddyManager != nil {
		if err := h.caddyManager.ApplyConfig(c.Request.Context()); err != nil {
			c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to apply configuration: " + err.Error()})
			return
		}
	}

	c.JSON(http.StatusOK, host)
}

// Delete removes a proxy host.
func (h *ProxyHostHandler) Delete(c *gin.Context) {
	uuid := c.Param("uuid")

	host, err := h.service.GetByUUID(uuid)
	if err != nil {
		c.JSON(http.StatusNotFound, gin.H{"error": "proxy host not found"})
		return
	}

	if err := h.service.Delete(host.ID); err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	if h.caddyManager != nil {
		if err := h.caddyManager.ApplyConfig(c.Request.Context()); err != nil {
			c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to apply configuration: " + err.Error()})
			return
		}
	}

	// Send Notification
	if h.notificationService != nil {
		h.notificationService.SendExternal(
			"proxy_host",
			"Proxy Host Deleted",
			fmt.Sprintf("Proxy Host %s deleted", host.Name),
			map[string]interface{}{
				"Name":   host.Name,
				"Action": "deleted",
			},
		)
	}

	c.JSON(http.StatusOK, gin.H{"message": "proxy host deleted"})
}

// TestConnection checks if the proxy host is reachable.
func (h *ProxyHostHandler) TestConnection(c *gin.Context) {
	var req struct {
		ForwardHost string `json:"forward_host" binding:"required"`
		ForwardPort int    `json:"forward_port" binding:"required"`
	}

	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}

	if err := h.service.TestConnection(req.ForwardHost, req.ForwardPort); err != nil {
		c.JSON(http.StatusBadGateway, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{"message": "Connection successful"})
}