package main

import (
	"bufio"
	"container/list"
	"fmt"
	"os"

	"github.com/fatih/color"
	"github.com/thoas/go-funk"
)

func readFileLines(filename string) ([]string, error) {
	var lines []string

	file, err := os.Open(filename)
	if err != nil {
		return lines, err
	}
	fileScanner := bufio.NewScanner(file)
	fileScanner.Split(bufio.ScanLines)

	for fileScanner.Scan() {
		lines = append(lines, fileScanner.Text())
	}

	return lines, nil
}

func getTotalAmountOfCards(cards []Card) uint64 {
	var result uint64 = 0
	cardStack := list.New()
	cardStack.Init()
	for _, card := range cards {
		cardStack.PushBack(card.id)
	}
	for cardStack.Len() > 0 {
		current := cardStack.Front()
		id := current.Value.(uint64)
		index := id - 1
		if cards[index].correctGuesses > 0 {
			for i := id; i < id+uint64(cards[index].correctGuesses); i++ {
				cardStack.PushBack(cards[i].id)
			}
		}
		result++
		cardStack.Remove(current)
	}
	return result
}

func main() {
	redPrint := color.New(color.FgRed)
	yellowPrint := color.New(color.FgYellow)
	if len(os.Args) < 2 {
		redPrint.Fprintln(os.Stderr, "You must provide the input file")
		os.Exit(1)
	}
	lines, err := readFileLines(os.Args[1])
	if err != nil {
		redPrint.Fprintln(os.Stderr, "Could not read input file")
		os.Exit(1)
	}
	var cards []Card
	var points []uint64
	for _, line := range lines {
		cards = append(cards, Card{})
		err := cards[len(cards)-1].parseCard(line)
		if err != nil {
			redPrint.Fprintf(os.Stderr, "Could not parse line '%s'\n", line)
		}
		points = append(points, cards[len(cards)-1].getPoints())
	}

	sumPart1 := funk.Reduce(points, func(acc, elem uint64) uint64 { return acc + elem }, uint64(0))
	fmt.Print("Part 1: ")
	yellowPrint.Print(sumPart1)
	fmt.Println()

	part2 := getTotalAmountOfCards(cards)
	fmt.Print("Part 1: ")
	yellowPrint.Print(part2)
	fmt.Println()
}