package api

import (
	"net/http"
	"strconv"
	"velvettear/badger/internal/config"
	"velvettear/badger/internal/library"
	"velvettear/badger/internal/log"
)

// exported function(s)
func StartServer() {
	serverAddress := config.ApiListen() + ":" + strconv.Itoa(config.ApiPort())
	registerEndpoints()
	log.Info("starting the api server", "address: '"+serverAddress+"'")
	error := http.ListenAndServe(serverAddress, nil)
	if error != nil {
		log.Fatal("encountered an error starting the api server", error.Error())
	}
}

// unexported function(s)
func registerEndpoints() {
	endpoint{
		address:  "/library/update",
		async:    false,
		function: library.Update,
	}.register()
	endpoint{
		address:  "/library/import",
		async:    false,
		function: library.Import,
	}.register()
	endpoint{
		address:  "/library/duplicates",
		async:    false,
		function: library.FindDuplicates,
	}.register()
}

func (endpoint endpoint) register() {
	log.Debug("registering api endpoint '" + endpoint.address + "'...")
	http.HandleFunc(endpoint.address, func(response http.ResponseWriter, request *http.Request) {
		log.Debug("called api endpoint '" + endpoint.address + "'...")
		if !runBlocking(endpoint.address) {
			response.Write([]byte("function '" + getRunning().functionName + "' is already running"))
			response.WriteHeader(503)
		}
		state := getRunning()
		msg := "function '" + state.functionName + "'"
		if endpoint.async {
			go endpoint.function.(func())()
			msg += " started asynchronously"
		} else {
			endpoint.function.(func())()
			msg += " finished after " + strconv.Itoa(int(finish().Milliseconds())) + "ms"
		}
		response.Write([]byte(msg))
	})
}

// struct(s)
type endpoint struct {
	address  string
	async    bool
	function interface{}
}