package day07

import java.io.File

/**
 * author:  vishnu
 * date:    5/23/17
 * purpose:
 */

val splitter = Regex("(?=\\b[\\[\\]])")

fun main(args: Array<String>) {
    val ipList = File("src/day07/ips.txt").readLines()
    println("TLS supported IPs: ${ipList.count { supportsTLS(it) }}")
    println("SSL supported IPs: ${ipList.count { supportsSSL(it) }}")
}

/* Part 1 */

fun supportsTLS(ip: String): Boolean {
    var bracketedHasMirrored = false
    var sectionHasMirrored = false
    ip.split(splitter).forEach {
        if (hasAbba(it)) {
            if (it.startsWith('[')) bracketedHasMirrored = true
            else sectionHasMirrored = true
        }
    }
    return !bracketedHasMirrored and sectionHasMirrored
}

fun hasAbba(section: String): Boolean {
    return (3..section.length - 1)
            .any {
                (section[it - 3] == section[it]) and (section[it - 2] == section[it - 1]) and
                        (section[it - 3] != section[it - 2])
            }
}

/* Part 2 */

fun supportsSSL(ip: String): Boolean {
    val sections = ip.split(splitter)
    sections.filter { !it.startsWith('[') }
            .forEach {
                val current = it
                (2..current.length - 1).forEach {
                    if ((current[it - 2] == current[it]) and (current[it - 2] != current[it - 1])) {
                        val bab = current[it - 1].toString() + current[it] + current[it - 1]
                        sections.filter { it.startsWith('[') }
                                .forEach {
                                    val currentBracketed = it
                                    (2..currentBracketed.length - 1).forEach {
                                        if ((currentBracketed[it - 2] == bab[0]) and
                                                (currentBracketed[it - 1] == bab[1]) and
                                                (currentBracketed[it] == bab[2])) {
                                            return true
                                        }
                                    }
                                }
                    }
                }
            }
    return false
}