package v1

import (
	"encoding/json"
	"fmt"
	"net"
	"net/http"
	"strings"

	"github.com/gorilla/mux"

	"github.com/wild-cloud/wild-central/internal/services"
)

// ServicesListAll lists all registered services.
func (api *API) ServicesListAll(w http.ResponseWriter, r *http.Request) {
	svcs, err := api.services.List()
	if err != nil {
		respondError(w, http.StatusInternalServerError, fmt.Sprintf("Failed to list services: %v", err))
		return
	}

	if svcs == nil {
		svcs = []services.Service{}
	}

	respondJSON(w, http.StatusOK, map[string]any{
		"services": svcs,
	})
}

// ServicesGet retrieves a service by domain.
func (api *API) ServicesGet(w http.ResponseWriter, r *http.Request) {
	domain := mux.Vars(r)["domain"]

	svc, err := api.services.Get(domain)
	if err != nil {
		respondError(w, http.StatusNotFound, fmt.Sprintf("Service not found: %v", err))
		return
	}

	respondJSON(w, http.StatusOK, svc)
}

// ServicesRegister creates or updates a service registration.
func (api *API) ServicesRegister(w http.ResponseWriter, r *http.Request) {
	var svc services.Service
	if err := json.NewDecoder(r.Body).Decode(&svc); err != nil {
		respondError(w, http.StatusBadRequest, fmt.Sprintf("Invalid request body: %v", err))
		return
	}

	// Validate routes
	for i, r := range svc.Routes {
		for _, p := range r.Paths {
			if !strings.HasPrefix(p, "/") {
				respondError(w, http.StatusBadRequest, fmt.Sprintf("Route %d: path prefix must start with /: %q", i, p))
				return
			}
		}
		for _, cidr := range r.IPAllow {
			if _, _, err := net.ParseCIDR(cidr); err != nil {
				respondError(w, http.StatusBadRequest, fmt.Sprintf("Route %d: invalid CIDR in ipAllow: %q", i, cidr))
				return
			}
		}
	}

	if err := api.services.Register(svc); err != nil {
		respondError(w, http.StatusBadRequest, fmt.Sprintf("Failed to register service: %v", err))
		return
	}

	// Return the stored version (has defaults applied)
	stored, _ := api.services.Get(svc.Domain)
	respondJSON(w, http.StatusCreated, map[string]any{
		"message": fmt.Sprintf("Service %q registered", svc.Domain),
		"service": stored,
	})
}

// ServicesUpdate applies partial updates to a service.
func (api *API) ServicesUpdate(w http.ResponseWriter, r *http.Request) {
	domain := mux.Vars(r)["domain"]

	var updates map[string]any
	if err := json.NewDecoder(r.Body).Decode(&updates); err != nil {
		respondError(w, http.StatusBadRequest, fmt.Sprintf("Invalid request body: %v", err))
		return
	}

	if err := api.services.Update(domain, updates); err != nil {
		respondError(w, http.StatusNotFound, fmt.Sprintf("Failed to update service: %v", err))
		return
	}

	svc, _ := api.services.Get(domain)
	respondJSON(w, http.StatusOK, map[string]any{
		"message": fmt.Sprintf("Service %q updated", domain),
		"service": svc,
	})
}

// ServicesDeregister removes a service registration.
func (api *API) ServicesDeregister(w http.ResponseWriter, r *http.Request) {
	domain := mux.Vars(r)["domain"]

	if err := api.services.Deregister(domain); err != nil {
		respondError(w, http.StatusNotFound, fmt.Sprintf("Failed to deregister service: %v", err))
		return
	}

	respondMessage(w, http.StatusOK, fmt.Sprintf("Service %q deregistered", domain))
}

// ServicesDeregisterBySource removes all services from a source with a given backend.
func (api *API) ServicesDeregisterBySource(w http.ResponseWriter, r *http.Request) {
	source := r.URL.Query().Get("source")
	backend := r.URL.Query().Get("backend")

	if source == "" {
		respondError(w, http.StatusBadRequest, "source query parameter is required")
		return
	}

	if err := api.services.DeregisterBySource(source, backend); err != nil {
		respondError(w, http.StatusInternalServerError, fmt.Sprintf("Failed to deregister: %v", err))
		return
	}

	respondMessage(w, http.StatusOK, fmt.Sprintf("Services from %q deregistered", source))
}