package main

import (
	"bufio"
	"fmt"
	"os"
	"sort"
)

type Game struct {
	Words map[string]*Word
}

type Word struct {
	Word  string
	Score int
}

func main() {

	game := NewGame()

	err := game.getWordsFromStdin()
	if err != nil {
		fmt.Printf("Error getting Words from stdin: %s\n", err)
		os.Exit(1)
	}

	err = game.scoreWordsByCommonLetterLocations()
	if err != nil {
		fmt.Printf("Error scoring Words: %s\n", err)
		os.Exit(1)
	}

	err = game.printSortedScores()
	if err != nil {
		fmt.Printf("Error printing sorted scores: %s\n", err)
		os.Exit(1)
	}

	// get guess and Score from stdin

	// remove Words that don't match guess and Score

}

func NewGame() *Game {
	return &Game{
		Words: make(map[string]*Word),
	}
}

func (g Game) printSortedScores() error {

	var sortedWordScores []string

	for _, word := range g.Words {
		sortedWordScores = append(sortedWordScores, word.Word)
	}

	// sort words by score
	sort.Slice(sortedWordScores, func(i, j int) bool {
		return g.Words[sortedWordScores[i]].Score > g.Words[sortedWordScores[j]].Score
	})

	fmt.Print("\nWords sorted by Score:\n")
	for _, word := range sortedWordScores {
		fmt.Printf("%s: %d\n", word, g.Words[word].Score)
	}
	fmt.Println("")

	return nil
}

func (g Game) scoreWordsByCommonLetterLocations() error {
	letterIdxScores := make(map[int]map[string]int)

	var lastWord string
	for _, word := range g.Words {
		word.Score = 0
		lastWord = word.Word
	}

	for idx, _ := range lastWord {
		letterIdxScores[idx] = make(map[string]int)
	}

	for _, word := range g.Words {
		for idx, letter := range word.Word {
			letterIdxScores[idx][string(letter)]++
		}
	}

	for _, word := range g.Words {
		for idx, letter := range word.Word {
			word.Score += letterIdxScores[idx][string(letter)]
		}
	}

	return nil
}

func (g Game) getWordsFromStdin() error {

	fmt.Println("Enter Words, one per line. Enter a period to end input.")

	wordLen := 0

	for {
		reader := bufio.NewReader(os.Stdin)
		word, _ := reader.ReadString('\n')
		word = word[:len(word)-1]
		if word == "." {
			fmt.Println("got Words!")
			break
		}

		if wordLen == 0 {
			wordLen = len(word)
		} else {
			if len(word) != wordLen {
				fmt.Printf("Error: All words must be the same length (%d), skipping: %s\n", wordLen, word)
				continue
			}
		}
		g.Words[word] = &Word{Word: word}
	}

	return nil
}