static def execThing (String cmd) {
	return cmd.execute().text.trim()
}

static def getCurrentGitHash() {
	return execThing('git rev-parse --short=8 HEAD')
}

static def generateVersionName() {
	// major version
	String versionTagsRaw = execThing('git tag --list v[0-9]*')
	int versionTagsCount = versionTagsRaw == "" ? 0 : versionTagsRaw.split('\n').size()

	// minor version
	String commitsSinceLastTag = "0"
	if (versionTagsCount > 1) {
		String lastVersionTag = execThing('git describe --match v[0-9]* --tags --abbrev=0')
		String gitLogResult = execThing("git log $lastVersionTag..HEAD --oneline")
		commitsSinceLastTag = gitLogResult == '' ? "0" : gitLogResult.split('\n').size()
	}


	// the commit we are building from

	// beta string, if this is a beta
	String lastTagName = (execThing('git tag --list') == "") ? "" : execThing('git describe --tags --abbrev=0')
	String lastTagHash = (lastTagName == "") ? "" : execThing("git log -1 --format=%h $lastTagName")
	String betaString = lastTagHash == getCurrentGitHash() && lastTagName.contains("-beta") ? '-beta' : ''

	return "$versionTagsCount.$commitsSinceLastTag$betaString"
}

ext.exec = { command ->
	return execThing(command)
}

ext.getVersionName = { ->
	return generateVersionName()
}

ext.getVersionCode = { ->
	String commitsCount = execThing("git rev-list --count HEAD")
	return Integer.valueOf(commitsCount)
}

ext.getDebugVersion = { ->
	return "git-${getCurrentGitHash()} (debug)"
}

ext.getReleaseVersion = { ->
	return "${generateVersionName()} (${getCurrentGitHash()})"
}

ext.updateManifestVersion = { versionCode, versionName ->
	def manifestFile = file("src/main/AndroidManifest.xml")

	def newManifest = manifestFile
		.getText()
		.replaceFirst(~"versionCode=\"([^\"]+)\"", "versionCode=\"" + versionCode + "\"")
		.replaceFirst(~"versionName=\"([^\"]+)\"", "versionName=\"" + versionName + "\"")

	manifestFile.write(newManifest)
}