hefbrug/src/main/kotlin/me/eater/hefbrug/selector/NodeSelector.kt

package me.eater.hefbrug.selector

import me.eater.hefbrug.node.Node

class NodeSelector(private val selector: NameSelector) : SelectorInterface {
    override fun matches(node: Node): Boolean {
        return selector.match(node.hostname)
    }

    constructor(selector: String) : this(
        if ("*" in selector) {
            NameSelector.RegexMatch(globToRegex(selector))
        } else {
            NameSelector.ExactMatch(selector)
        }
    )

    constructor(selector: Regex) : this(NameSelector.RegexMatch(selector))

    sealed class NameSelector {
        data class ExactMatch(val name: String) : NameSelector() {
            override fun match(name: String) = name == this.name
        }

        data class RegexMatch(val regex: Regex) : NameSelector() {
            override fun match(name: String) = regex.matches(name)
        }

        abstract fun match(name: String): Boolean
    }

    companion object {
        fun globToRegex(glob: String): Regex {
            val regexStr = glob
                .replace(Regex("""\*+""")) { """\E.+\Q""" }
                .replace(Regex("""\?+""")) { """\E[^\.]+\Q""" }
                .replace("""\Q\E""", "")

            return Regex("""^\Q$regexStr\E$""", RegexOption.IGNORE_CASE)
        }
    }
}