package main

import (
	"bufio"
	"fmt"
	"os"
	"strings"
	"time"
)

const FILE_PATH = "./input.txt"

//const FILE_PATH = "./sample.txt"

func LoadInput(filename string) ([]string, error) {
	file, err := os.Open(filename)
	if err != nil {
		return nil, err
	}
	defer file.Close()

	var lines []string
	scanner := bufio.NewScanner(file)
	for scanner.Scan() {
		lines = append(lines, scanner.Text())
	}

	if err := scanner.Err(); err != nil {
		return nil, err
	}

	return lines, nil
}

type Puzzle struct {
	poss  []string
	lines []string
}

type structuredInput = Puzzle

func TransformInput(lines []string) structuredInput {
	return Puzzle{strings.Split(lines[0], ", "), lines[2:]}
}

var poss []string
var cachePart1 map[string]bool = make(map[string]bool)

func hasSolution(input string) bool {
	if len(input) == 0 {
		return true
	}

	value, ok := cachePart1[input]

	if ok {
		return value
	}

	var result = false

	for i := 0; i < len(poss); i++ {
		if len(input) >= len(poss[i]) && input[:len(poss[i])] == poss[i] && hasSolution(input[len(poss[i]):]) {
			result = true
			break
		}
	}

	cachePart1[input] = result
	return result
}

func Part1(input structuredInput) int {
	var result = 0
	poss = input.poss

	for _, line := range input.lines {
		if hasSolution(line) {
			result++
		}
	}

	return result
}

var cachePart2 map[string]int = make(map[string]int)

func findSolutionCount(input string) int {
	if len(input) == 0 {
		return 1
	}

	value, ok := cachePart2[input]

	if ok {
		return value
	}

	var result = 0

	for i := 0; i < len(poss); i++ {
		if len(input) >= len(poss[i]) && input[:len(poss[i])] == poss[i] {
			result += findSolutionCount(input[len(poss[i]):])
		}
	}

	cachePart2[input] = result
	return result
}

func Part2(input structuredInput) int {
	var result = 0
	poss = input.poss

	for _, line := range input.lines {
		result += findSolutionCount(line)
	}

	return result
}

func main() {
	var start time.Time
	var elapsed time.Duration = 0
	input, err := LoadInput(FILE_PATH)
	if err != nil {
		fmt.Println("Error loading input:", err)
		return
	}

	structuredInput := TransformInput(input)
	fmt.Println("Structured Input:", structuredInput)

	start = time.Now()
	fmt.Println("Solution Part 1: ", Part1(structuredInput))
	elapsed = time.Since(start)
	fmt.Printf("Part 1 took %s\n", elapsed)

	start = time.Now()
	fmt.Println("Solution Part 2: ", Part2(structuredInput))
	elapsed = time.Since(start)
	fmt.Printf("Part 2 took %s\n", elapsed)
}