package main

import (
	"encoding/csv"
	"fmt"
	"io"
	"log"
	"os"
	"strconv"
)

func main() {

	blocks := load_blocks()
	// fmt.Println("Total blocks:", len(blocks))

	// Parse parameters
	// Turn parameters into rows
	row1 := "769104803"
	row2 := "154800060"
	row3 := "002700150"
	row4 := "600900308"
	row5 := "045328670"
	row6 := "328670945"
	row7 := "597410280"
	row8 := "006284090"
	row9 := "200590006"

	// Find rows that fit with the entered rows
	rows1 := find_blocks(blocks, row1)
	rows2 := find_blocks(blocks, row2)
	rows3 := find_blocks(blocks, row3)
	rows4 := find_blocks(blocks, row4)
	rows5 := find_blocks(blocks, row5)
	rows6 := find_blocks(blocks, row6)
	rows7 := find_blocks(blocks, row7)
	rows8 := find_blocks(blocks, row8)
	rows9 := find_blocks(blocks, row9)

	// fmt.Println(rows1)
	// fmt.Println(rows2)
	// fmt.Println(rows3)
	// fmt.Println(rows4)
	// fmt.Println(rows5)
	// fmt.Println(rows6)
	// fmt.Println(rows7)
	// fmt.Println(rows8)
	// fmt.Println(rows9)

	// fmt.Println("len(rows1):", len(rows1))
	// fmt.Println("len(rows2):", len(rows2))
	// fmt.Println("len(rows3):", len(rows3))
	// fmt.Println("len(rows4):", len(rows4))
	// fmt.Println("len(rows5):", len(rows5))
	// fmt.Println("len(rows6):", len(rows6))
	// fmt.Println("len(rows7):", len(rows7))
	// fmt.Println("len(rows8):", len(rows8))
	// fmt.Println("len(rows9):", len(rows9))

	fmt.Println("Number of iterations:", len(rows1)*len(rows2)*len(rows3)*len(rows4)*len(rows5)*len(rows6)*len(rows7)*len(rows8)*len(rows9))
	iter := len(rows1) * len(rows2) * len(rows3) * len(rows4) * len(rows5) * len(rows6) * len(rows7) * len(rows8) * len(rows9)

	solutions := check_combinations(rows1, rows2, rows3, rows4, rows5, rows6, rows7, rows8, rows9, iter)

	fmt.Println(solutions)

}

func check_combinations(rows1 []int, rows2 []int, rows3 []int, rows4 []int, rows5 []int, rows6 []int, rows7 []int, rows8 []int, rows9 []int, iter int) []string {
	var combinations []string
	var counter int
	var percentage float32

	for rows1_index := range rows1 {
		for rows2_index := range rows2 {
			for rows3_index := range rows3 {
				for rows4_index := range rows4 {
					for rows5_index := range rows5 {
						for rows6_index := range rows6 {
							for rows7_index := range rows7 {
								for rows8_index := range rows8 {
									for rows9_index := range rows9 {
										if validate_combination(rows1[rows1_index], rows2[rows2_index], rows3[rows3_index], rows4[rows4_index], rows5[rows5_index], rows6[rows6_index], rows7[rows7_index], rows8[rows8_index], rows9[rows9_index]) {
											combinations = append(combinations, render_combination(rows1[rows1_index], rows2[rows2_index], rows3[rows3_index], rows4[rows4_index], rows5[rows5_index], rows6[rows6_index], rows7[rows7_index], rows8[rows8_index], rows9[rows9_index]))
										}
										counter = counter + 1
										if counter%1000000 == 0 {
											percentage = (float32(counter) / (float32(iter) / 100))
											fmt.Println("Processing:", percentage, "%")
										}
									}
								}
							}
						}
					}
				}
			}
		}
	}

	return combinations
}

func validate_combination(row1 int, row2 int, row3 int, row4 int, row5 int, row6 int, row7 int, row8 int, row9 int) bool {
	var retval bool
	retval = true

	row1s := strconv.Itoa(row1)
	row2s := strconv.Itoa(row2)
	row3s := strconv.Itoa(row3)
	row4s := strconv.Itoa(row4)
	row5s := strconv.Itoa(row5)
	row6s := strconv.Itoa(row6)
	row7s := strconv.Itoa(row7)
	row8s := strconv.Itoa(row8)
	row9s := strconv.Itoa(row9)

	for index := range 9 {
		if row1s[index] == row2s[index] || row1s[index] == row3s[index] || row1s[index] == row4s[index] || row1s[index] == row5s[index] || row1s[index] == row6s[index] || row1s[index] == row7s[index] || row1s[index] == row8s[index] || row1s[index] == row9s[index] {
			retval = false
		}

		if row2s[index] == row1s[index] || row2s[index] == row3s[index] || row2s[index] == row4s[index] || row2s[index] == row5s[index] || row2s[index] == row6s[index] || row2s[index] == row7s[index] || row2s[index] == row8s[index] || row2s[index] == row9s[index] {
			retval = false
		}

		if row3s[index] == row1s[index] || row3s[index] == row2s[index] || row3s[index] == row4s[index] || row3s[index] == row5s[index] || row3s[index] == row6s[index] || row3s[index] == row7s[index] || row3s[index] == row8s[index] || row3s[index] == row9s[index] {
			retval = false
		}

		if row4s[index] == row1s[index] || row4s[index] == row2s[index] || row4s[index] == row3s[index] || row4s[index] == row5s[index] || row4s[index] == row6s[index] || row4s[index] == row7s[index] || row4s[index] == row8s[index] || row4s[index] == row9s[index] {
			retval = false
		}

		if row5s[index] == row1s[index] || row5s[index] == row2s[index] || row5s[index] == row3s[index] || row5s[index] == row4s[index] || row5s[index] == row6s[index] || row5s[index] == row7s[index] || row5s[index] == row8s[index] || row5s[index] == row9s[index] {
			retval = false
		}

		if row6s[index] == row1s[index] || row6s[index] == row2s[index] || row6s[index] == row3s[index] || row6s[index] == row4s[index] || row6s[index] == row5s[index] || row6s[index] == row7s[index] || row6s[index] == row8s[index] || row6s[index] == row9s[index] {
			retval = false
		}

		if row7s[index] == row1s[index] || row7s[index] == row2s[index] || row7s[index] == row3s[index] || row7s[index] == row4s[index] || row5s[index] == row6s[index] || row7s[index] == row6s[index] || row7s[index] == row8s[index] || row7s[index] == row9s[index] {
			retval = false
		}

		if row8s[index] == row1s[index] || row8s[index] == row2s[index] || row8s[index] == row3s[index] || row8s[index] == row4s[index] || row8s[index] == row5s[index] || row8s[index] == row6s[index] || row8s[index] == row7s[index] || row8s[index] == row9s[index] {
			retval = false
		}

		if row9s[index] == row1s[index] || row9s[index] == row2s[index] || row9s[index] == row3s[index] || row9s[index] == row4s[index] || row9s[index] == row5s[index] || row9s[index] == row6s[index] || row9s[index] == row7s[index] || row9s[index] == row8s[index] {
			retval = false
		}

	}

	return retval
}

func render_combination(row1 int, row2 int, row3 int, row4 int, row5 int, row6 int, row7 int, row8 int, row9 int) string {

	row1s := strconv.Itoa(row1)
	row2s := strconv.Itoa(row2)
	row3s := strconv.Itoa(row3)
	row4s := strconv.Itoa(row4)
	row5s := strconv.Itoa(row5)
	row6s := strconv.Itoa(row6)
	row7s := strconv.Itoa(row7)
	row8s := strconv.Itoa(row8)
	row9s := strconv.Itoa(row9)

	// combination = row1s + "\n" + row2s + "\n" + row3s + "\n" + row4s + "\n" + row5s + "\n" + row6s + "\n" + row7s + "\n" + row8s + "\n" + row9s + "\n"

	return row1s + "\n" + row2s + "\n" + row3s + "\n" + row4s + "\n" + row5s + "\n" + row6s + "\n" + row7s + "\n" + row8s + "\n" + row9s + "\n"
}

func find_blocks(blocks []int, row string) []int {
	// Declare selection
	var selection []int
	var curr_blocks []int

	// fmt.Println(row)
	for letter := range row {

		if len(selection) == 0 {
			curr_blocks = blocks
		} else {
			curr_blocks = selection
			selection = nil
		}

		// fmt.Println("Letter:", row[letter])
		// fmt.Println("len(curr_blocks):", len(curr_blocks))
		// fmt.Println("curr_blocks[0]:", curr_blocks[0])

		for block := range curr_blocks {

			curr_row := strconv.Itoa(curr_blocks[block])

			if row[letter] == curr_row[letter] {
				found_row, _ := strconv.Atoi(curr_row)
				selection = append(selection, found_row)
			}
			if row[letter] == '0' {
				found_row, _ := strconv.Atoi(curr_row)
				selection = append(selection, found_row)
			}

		} // End for-loop

	} // End for-loop

	// Return selection
	return selection
}

func load_blocks() []int {
	var blocks []int

	file, err := os.Open("blocks.csv")
	if err != nil {
		panic(err)
	}
	defer file.Close()

	r := csv.NewReader(file)
	for {
		record, err := r.Read()
		if err == io.EOF {
			break
		}
		if err != nil {
			log.Fatal(err)
		}

		block, _ := strconv.Atoi(record[0])
		blocks = append(blocks, block)
	}

	return blocks
}

func generate_blocks() []int {

	var blocks []int
	decvals := [9]int{49, 50, 51, 52, 53, 54, 55, 56, 57}

	for counter := 123456789; counter <= 987654321; counter++ {

		// Convert number to string ([]byte)
		digits := strconv.Itoa(counter)

		// Check if every number is only represented only once
		var valid bool
		valid = true
		for decval := range decvals {
			var count int
			for digit := range digits {
				if digits[digit] == byte(decvals[decval]) {
					count = count + 1
				}
			}

			if count != 1 {
				valid = false
			}
		}

		if valid {
			blocks = append(blocks, counter)
		}
	}

	return blocks

}

func print_block(block int) {
	digits := strconv.Itoa(block)
	fmt.Printf("%c %c %c\n%c %c %c\n%c %c %c\n\n", digits[0], digits[1], digits[2], digits[3], digits[4], digits[5], digits[6], digits[7], digits[8])
}