package main

import (
	"encoding/json"
	"io"
	"log"
	"net/http"
	"os"
	"slices"
	"strconv"
	"time"

	"gitlab.hamburg.ccc.de/ccchh/spaceapid/types"
)

func main() {
	validUsername, success := os.LookupEnv("DOORIS_USERNAME")
	if !success || validUsername == "" {
		log.Fatalln("Could not retrieve DOORIS_API_KEY env variable or variable is empty")
	}

	validPassword, success := os.LookupEnv("DOORIS_PASSWORD")
	if !success || validPassword == "" {
		log.Fatalln("Could not retrieve DOORIS_API_KEY env variable or variable is empty")
	}

	initialJson, success := os.LookupEnv("SPACE_API_JSON")
	if !success || initialJson == "" {
		log.Fatalln("Could not retrieve SPACE_API_JSON env variable or variable is empty")
	}

	spaceApiResponse := new(types.SpaceAPIResponseV14)
	err := json.Unmarshal([]byte(initialJson), spaceApiResponse)
	if err != nil {
		log.Fatalln("Could not parse provided JSON")
	}

	if !slices.Contains(spaceApiResponse.APICompatibility, "14") {
		log.Fatalln("Provided JSON doesn't specify compatibility with API version 14")
	}

	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
		if r.Method != http.MethodGet {
			log.Println("Wrong METHOD from", r.RemoteAddr)
			w.Header().Set("allow", http.MethodGet)
			w.WriteHeader(http.StatusMethodNotAllowed)
			return
		}

		response, err := json.Marshal(spaceApiResponse)
		if err != nil {
			log.Println("Failed to serialize JSON response")
			w.WriteHeader(http.StatusInternalServerError)
			return
		}

		w.WriteHeader(http.StatusOK)
		_, _ = w.Write(response)
	})

	http.HandleFunc("/state/open", func(w http.ResponseWriter, r *http.Request) {
		username, password, ok := r.BasicAuth()
		if !ok || username != validUsername || password != validPassword {
			log.Println("Unauthorized request from", r.RemoteAddr)
			w.Header().Set("www-authentication", "Basic realm=\"space-api\"")
			w.WriteHeader(http.StatusUnauthorized)
			return
		}

		if r.Method != http.MethodPut {
			log.Println("Wrong METHOD from", r.RemoteAddr)
			w.Header().Set("allow", http.MethodPut)
			w.WriteHeader(http.StatusMethodNotAllowed)
			return
		}

		body, err := io.ReadAll(r.Body)
		if err != nil {
			log.Println("Failed to read request body from", r.RemoteAddr)
			w.WriteHeader(http.StatusInternalServerError)
			_, _ = io.WriteString(w, "Failed reading HTTP request body")
			return
		}

		newState, err := strconv.ParseBool(string(body))
		if err != nil {
			log.Println("Failed to parse request body from", r.RemoteAddr)
			w.WriteHeader(http.StatusBadRequest)
			_, _ = io.WriteString(w, "HTTP request body should either be true or false")
			return
		}

		spaceApiResponse.State.Open = newState
		spaceApiResponse.State.LastChange = time.Now().Unix()

		w.WriteHeader(http.StatusOK)
		_, _ = io.WriteString(w, "Update Successful")
	})

	log.Println("Starting HTTP server...")
	log.Fatalln(http.ListenAndServe(":8080", nil))
}