package main

import (
	"bytes"
	"encoding/json"
	"fmt"
	"github.com/go-co-op/gocron/v2"
	"github.com/joho/godotenv"
	"log"
	"math/rand/v2"
	"net/http"
	"os"
	"strconv"
	"time"
)

var loginPath string = "/login"
var subscriptionsPath string = "/subscriptions"

type AuthResult struct {
	Token string
}

type Subscription struct {
	Url      string
	Name     string
	Avatar   string
	Verified bool
}

func login(basePath string, username string, password string) AuthResult {
	loginUrl := basePath + loginPath
	login := map[string]string{"username": username, "password": password}

	jsonLogin, _ := json.Marshal(login)

	res, err := http.Post(loginUrl, "application/json", bytes.NewBuffer(jsonLogin))
	if err != nil {
		panic(err)
	}
	defer res.Body.Close()

	var authResult AuthResult
	authResultDecoder := json.NewDecoder(res.Body)
	err = authResultDecoder.Decode(&authResult)
	if err != nil {
		panic(err)
	}
	return authResult
}

func getSubscriptions(basePath string, authToken string) []Subscription {
	subscriptionsUrl := basePath + subscriptionsPath

	// Create a new request using http
	req, err := http.NewRequest("GET", subscriptionsUrl, nil)
	if err != nil {
		panic(err)
	}

	req.Header.Add("Authorization", authToken)

	client := &http.Client{}
	res, err := client.Do(req)
	if err != nil {
		log.Println("Error on response.\n[ERROR] -", err)
	}
	defer res.Body.Close()

	var subsResult []Subscription
	subsResultDecoder := json.NewDecoder(res.Body)
	err = subsResultDecoder.Decode(&subsResult)
	if err != nil {
		panic(err)
	}
	return subsResult
}

func visit(url string, authToken string) {
	req, err := http.NewRequest("GET", url, nil)
	if err != nil {
		panic(err)
	}

	req.Header.Add("Authorization", authToken)

	client := &http.Client{}
	res, err := client.Do(req)
	if err != nil {
		log.Println("Error on response.\n[ERROR] -", err)
	}
	defer res.Body.Close()
	fmt.Println(res.Status)
}

// Randomize subscription order
func randomize[S any](slice []S) {
	for i := range slice {
		j := rand.IntN(i + 1)
		slice[i], slice[j] = slice[j], slice[i]
	}
}

// Update Piped videos for all subscriptions given the Piped instance and the matching login data
func update(basePath string, maxWaitTime int, username string, password string) {
	authResult := login(basePath, username, password)
	subscriptions := getSubscriptions(basePath, authResult.Token)

	randomize(subscriptions)

	for i := range subscriptions {
		fmt.Println(subscriptions[i].Name)
		visit(basePath+subscriptions[i].Url, authResult.Token)

		randomWaitTime := time.Duration(rand.IntN(maxWaitTime)) * time.Millisecond
		fmt.Println("Waiting for", randomWaitTime)
		fmt.Println("")
		time.Sleep(randomWaitTime)
	}
}

func main() {
	err := godotenv.Load()

	if err != nil {
		fmt.Println("Couldn't find a .env file, assuming already present environment variables")
	}

	var username string = os.Getenv("PIPED_USERNAME")              // piped username
	var password string = os.Getenv("PIPED_PASSWORD")              // piped password
	var basePath string = os.Getenv("PIPED_API_URL")               // piped API URL
	var cronSchedule string = os.Getenv("QUERY_CRON")              // cron schedule how often update should be triggered
	maxWaitTime, err := strconv.Atoi(os.Getenv("QUERY_WAIT_TIME")) // in milliseconds, change for potential ban evasion
	if err != nil {
		panic(err)
	}

	fmt.Printf("Logging in as %s on Piped instance %s\n", username, basePath)

	var infinityDuration time.Duration = 42069 * time.Hour // basically infinity

	// create a scheduler
	s, err := gocron.NewScheduler(gocron.WithStopTimeout(infinityDuration)) // we don't want the lengthy update task to time out
	if err != nil {
		panic(err)
	}

	// add a job to the scheduler
	_, err = s.NewJob(
		gocron.CronJob(
			cronSchedule,
			false,
		),
		gocron.NewTask(
			func() {
				update(basePath, maxWaitTime, username, password)
			},
		),
		gocron.WithSingletonMode(gocron.LimitModeReschedule),
	)
	if err != nil {
		panic(err)
	}

	// start the scheduler
	s.Start()

	fmt.Print("Starting scheduler...\n\n")

	// block until you are ready to shut down
	select {
	case <-time.After(time.Minute):
	}

	// when you're done, shut it down
	err = s.Shutdown()
	if err != nil {
		panic(err)
	}
}