package webapi

import (
	"fmt"
	"log"
	"net/http"

	"gitea.nehmer.net/torben/dyndns/service"
)

func init() {
	router.HandleFunc("/update", handleUpdate)
}

func handleUpdate(w http.ResponseWriter, r *http.Request) {
	err := r.ParseForm()
	if err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	ur, err := createUpdateRequestFromForm(r.Form)
	if err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	uc, err := service.LoadConfigForUser(ur.UserName, ur.Password)
	if err != nil {
		if _, ok := err.(*service.UnauthorizedError); ok {
			http.Error(w, err.Error(), http.StatusUnauthorized)
		} else {
			http.Error(w, err.Error(), http.StatusInternalServerError)
		}
		log.Printf("Authorization failed: %v", err)
		return
	}

	ur.Config = uc

	// Start DEBUG Output
	log.Println("Final request")
	log.Println(ur.PrettyPrint())
	for _, other := range uc.Others {
		log.Printf("Other %s, IID %v, merged: %v",
			other.Hostname, other.V6IID, other.ConvertIIDToAddress(ur.IPv6Net))
	}

	log.Println("WebAPI Config:")
	log.Println(C.PrettyPrint())
	log.Println("Service Config:")
	log.Println(service.C.PrettyPrint())
	// End DEBUG Output

	if err := processUpdateRequest(ur); err != nil {
		log.Printf("failed to process UpdateRequest: %v", err)
		http.Error(w, err.Error(), http.StatusInternalServerError)
	}

	w.Header().Set("Content-Type", "text/plain")
	fmt.Fprintln(w, "OK")
}

func processUpdateRequest(ur *UpdateRequest) error {
	nfu := service.NewNFTUpdate()

	if err := service.DNSUpdateEntry(ur.Config.Domain, ur.Config.Router.Hostname, ur.IPv4, ur.IPv6); err != nil {
		return fmt.Errorf("failed to update router DNS: %v", err)
	}
	if ur.Config.Router.NFT.Table != "" {
		if ur.IPv4 != nil && ur.Config.Router.NFT.Set4 != "" {
			if err := nfu.AddIP(ur.Config.Router.NFT.Table, ur.Config.Router.NFT.Set4, ur.IPv4); err != nil {
				return fmt.Errorf("failed to update IPv4 Router NFT setup: %v", err)
			}
		}
		if ur.IPv6 != nil && ur.Config.Router.NFT.Set6 != "" {
			if err := nfu.AddIP(ur.Config.Router.NFT.Table, ur.Config.Router.NFT.Set6, ur.IPv6); err != nil {
				return fmt.Errorf("failed to update IPv6 Router NFT setup: %v", err)
			}
		}
	}

	for _, other := range ur.Config.Others {
		fullV6IP := other.ConvertIIDToAddress(ur.IPv6Net)
		if other.RegisterV4 {
			if err := service.DNSUpdateEntry(ur.Config.Domain, other.Hostname, ur.IPv4, fullV6IP); err != nil {
				return fmt.Errorf("failed to update DNS for host %s: %v", other.Hostname, err)
			}
		} else {
			if err := service.DNSUpdateEntry(ur.Config.Domain, other.Hostname, nil, fullV6IP); err != nil {
				return fmt.Errorf("failed to update DNS for host %s: %v", other.Hostname, err)
			}
		}

		if other.NFT.Table != "" {
			if other.NFT.Set6 != "" {
				if err := nfu.AddIP(other.NFT.Table, other.NFT.Set6, fullV6IP); err != nil {
					return fmt.Errorf("failed to update IPv6 NFT setup for host %s: %v", other.Hostname, err)
				}
			}
			if other.RegisterV4 && other.NFT.Set4 != "" {
				if err := nfu.AddIP(other.NFT.Table, other.NFT.Set4, ur.IPv4); err != nil {
					return fmt.Errorf("failed to update IPv6 NFT setup for host %s: %v", other.Hostname, err)
				}
			}
		}
	}

	log.Println("Summary of collected NFT Updates:")
	log.Println(nfu.PrettyPrint())

	if err := nfu.Process(); err != nil {
		return fmt.Errorf("failed to update NFT Setup: %v", err)
	}

	return nil
}