#!/bin/bash

bindir="$(dirname $0)"
basedir="$(dirname $bindir)"
verdir="${basedir}/versions"
args=("$@")

run_gradle() {
	"${verdir}/${v_found}/bin/gradle" "${args[@]}"
	exit $?
}

contains() {
	local e
	for e in $2; do
		[[ $e == $1 ]] && return 0;
	done
	return 1
}

# key-value pairs of what gradle version (value) each gradle plugin version
# (key) should accept. plugin versions are actually prefixes and catch sub-
# versions as well. Pairs are taken from:
# https://developer.android.com/studio/releases/gradle-plugin.html#updating-gradle
d_plugin_k=(3.1 3.0 2.3    2.2  2.1.3  2.1  2.0 1.5 1.3 1.2   1.1   1.0 0.14 0.13 0.12 0.11 0.10  0.9  0.8 0.7 0.6 0.5 0.4 0.3 0.2)
d_plugin_v=(4.4 4.1 3.3 2.14.1 2.14.1 2.12 2.12 2.4 2.4 2.3 2.2.1 2.2.1  2.1  2.1 1.12 1.12 1.12 1.11 1.10 1.9 1.8 1.6 1.6 1.4 1.4)

# All gradle versions we know about
plugin_v=(4.8.1 4.8 4.7 4.6 4.5.1 4.5 4.4.1 4.4 4.3.1 4.3 4.2.1 4.2 4.1 4.0.2 4.0.1 4.0 3.5.1 3.5 3.4.1 3.4 3.3 3.2.1 3.2 3.1 3.0 2.14.1 2.14 2.13 2.12 2.11 2.10 2.9 2.8 2.7 2.6 2.5 2.4 2.3 2.2.1 2.2 2.1 1.12 1.11 1.10 1.9 1.8 1.7 1.6 1.4)

v_all=${plugin_v[@]}
echo "Available gradle versions: ${v_all[@]}"

# Earliest takes priority
for f in {.,..}/gradle/wrapper/gradle-wrapper.properties; do
	[[ -f $f ]] || continue
	while read l; do
		if [[ $l == 'distributionUrl='* ]]; then
			wrapper_ver=$(echo -n "$l" | sed "s/.*gradle-\\([0-9\\.\\+]\\+\\).*/\\1/")
		fi
	done < $f
done

if [[ -n $wrapper_ver ]]; then
	v_found=$wrapper_ver
	echo "Found $v_found via distributionUrl"
	run_gradle
fi

# Earliest takes priority
for f in {.,..}/build.gradle; do
	[[ -f $f ]] || continue
	while read l; do
		if [[ -z "$plugin_pver" && $l == *'com.android.tools.build:gradle:'* ]]; then
			plugin_pver=$(echo -n "$l" | sed "s/.*com.android.tools.build:gradle:\\([0-9\\.\\+]\\+\\).*/\\1/")
		elif [[ -z "$wrapper_ver" && $l == *'gradleVersion = '* ]]; then
			wrapper_ver=$(echo -n "$l" | sed "s/.*gradleVersion *=* *[\"']\\([0-9\\.]\\+\\)[\"'].*/\\1/")
		fi
	done < $f
done

if [[ -n $wrapper_ver ]]; then
	v_found=$wrapper_ver
	echo "Found $v_found via gradleVersion"
	run_gradle
fi

if [[ -n $plugin_pver ]]; then
	i=0
	match=false
	for k in ${d_plugin_k[@]}; do
		if [[ $plugin_pver == ${k}* ]]; then
			plugin_ver=${d_plugin_v[$i]}
			match=true
			break
		fi
		let i++
	done
	if $match; then
		v_found=$plugin_ver
		echo "Found $v_found via gradle plugin version $k"
	fi
fi

# Find the highest version available
for v in ${plugin_v[*]}; do
	if contains $v "${v_all[*]}"; then
		v_def=$v
		break
	fi
done

if [[ -z $v_found ]]; then
	echo "No suitable gradle version found - defaulting to $v_def"
	v_found=$v_def
fi

run_gradle