package day07

import (
	"regexp"
	"tools"
)

var reSplit = regexp.MustCompile(`^([^\[]+)|(?:\[([^]]+)]([^\[]+))`)

func isABBA(s string) bool {
	for i := 3; i < len(s); i++ {
		if s[i] == s[i-3] && s[i-1] == s[i-2] && s[i] != s[i-1] {
			return true
		}
	}

	return false
}

func getABAs(s string) (abaList []string) {
	for i := 2; i < len(s); i++ {
		if s[i] == s[i-2] && s[i] != s[i-1] {
			abaList = append(abaList, string(s[i-1])+string(s[i])+string(s[i-1]))
		}
	}

	return abaList
}

func hasABA(s, aba string) bool {
	for i := 2; i < len(s); i++ {
		if s[i] == aba[2] && s[i-1] == aba[1] && s[i-2] == aba[0] {
			return true
		}
	}
	return false
}

func Part1(puzzle tools.AoCPuzzle) interface{} {
	tlsCounter := 0
	for _, line := range puzzle.GetInputArray() {
		parts := reSplit.FindAllStringSubmatch(line, -1)
		thisABBA := false
		thisHNABBA := false
		if isABBA(parts[0][0]) {
			thisABBA = true
		}
		for i := 1; i < len(parts); i++ {
			if isABBA(parts[i][2]) {
				thisHNABBA = true
			}
			if isABBA(parts[i][3]) {
				thisABBA = true
			}
		}
		if thisABBA && !thisHNABBA {
			tlsCounter++
		}
	}

	return tlsCounter
}

func Part2(puzzle tools.AoCPuzzle) interface{} {
	sslCounter := 0
	for _, line := range puzzle.GetInputArray() {
		var abaList []string
		var hnList []string
		abaInHN := false
		parts := reSplit.FindAllStringSubmatch(line, -1)
		for _, aba := range getABAs(parts[0][0]) {
			abaList = append(abaList, aba)
		}
		for i := 1; i < len(parts); i++ {
			for _, aba := range getABAs(parts[i][3]) {
				abaList = append(abaList, aba)
			}
			hnList = append(hnList, parts[i][2])
		}
		for _, aba := range abaList {
			for _, hn := range hnList {
				if hasABA(hn, aba) {
					abaInHN = true
					break
				}
			}
			if abaInHN {
				break
			}
		}
		if abaInHN {
			sslCounter++
		}
	}

	return sslCounter
}