package day2

import (
	"bufio"
	"fmt"
	"log"
	"os"
	"strconv"
	"strings"
)

var Restriction map[string]int = map[string]int{
	"red": 12,
	"green": 13,
	"blue": 14,
}

type Game struct {
	Num int
	Sets []map[string]int
}

// now i need to encode the restriction,
// code 'compare game to restriction'
// scan though input lines, keep only numbers of games that pass the restriction, or rather sum them

func Run() int {
	filename := "./day2/input"
	file, err := os.Open(filename)
	if err != nil {
		panic(fmt.Sprintf("error opening file", filename))
	}
	defer file.Close()

	scanner := bufio.NewScanner(file)

	result := 0

	for scanner.Scan() {
		line := scanner.Text()
		game := ReadLine(line)
		log.Printf("reading %s got game %+v it is %t", line, game, game.isPossible(Restriction))
		if game.isPossible(Restriction) {
			result += game.Num
		}
	}

	return result
}

func (g Game)isPossible(restriction map[string]int) bool {
	for color, maxAmount := range restriction {
		for _, set := range g.Sets {
			seenAmount, found := set[color]
			if found && seenAmount > maxAmount {
				return false
			}
		}
	}
	return true
}

func ReadLine(line string) Game {
	result := Game{}
	result.Sets = make([]map[string]int, 0)

	infoIndex := strings.IndexRune(line, ':')
	gameTitle := line[0:infoIndex]
	titleNumStr := strings.Split(gameTitle, " ")[1]
	titleNum, err := strconv.Atoi(titleNumStr)
	if err != nil {
		panic(fmt.Sprintf("error getting game number from %s\n", line))
	}
	result.Num = titleNum

	setsLints := strings.Split(line[infoIndex+1:], ";")
	for _, set := range setsLints {
		result.Sets = append(result.Sets, readSet(set))
	}
	return result
}

// line like this
// 8 green, 6 blue, 20 red
func readSet(setLine string) map[string]int {
	log.Printf("> reading set: %s", setLine)
	result := make(map[string]int)
	itemLines := strings.Split(setLine, ",")
	for _, line := range itemLines {
		keyValue := strings.Split(strings.Trim(line, " "), " ")
		if len(keyValue) != 2 {
			panic(fmt.Sprintf("part '%s' of '%s' was of wrong lenght! %+v len is %d", line, setLine, keyValue, len(keyValue)))
		}
		num, err := strconv.Atoi(keyValue[0])
		if err != nil {
			panic(fmt.Sprint(setLine, line, err))
		}
		result[keyValue[1]] = num
	}

	return result
}