#!/bin/bash

# Copyright 2016 Google Inc. All Rights Reserved.
#
# Licensed under the MIT License, <LICENSE or http://opensource.org/licenses/MIT>.
# This file may not be copied, modified, or distributed except according to those terms.

# Pre-push hook for the tarpc repository. To use this hook, copy it to .git/hooks in your repository
# root.
#
# This hook runs tests to make sure only working code is being pushed. If present, rustup is used
# to build and test the code on the appropriate toolchains. The working copy must not contain
# uncommitted changes, since the script currently just runs cargo build/test in the working copy.
#
# Options:
#
# - TARPC_ALLOW_DIRTY, default = 0
#
#   Setting this variable to 1 will run tests even though there are code changes in the working
#   copy. Set to 0 by default, since the intent is to test the code that's being pushed, not changes
#   still in the working copy.
#
# - TARPC_USE_CURRENT_TOOLCHAIN, default = 0
#
#   Setting this variable to 1 will just run cargo build and cargo test, rather than running
#   stable/beta/nightly.
#
# Note that these options are most useful for testing the hooks themselves. Use git push --no-verify
# to skip the pre-push hook altogether.

RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[0;33m'
NC='\033[0m' # No Color

PREFIX="${GREEN}[PREPUSH]${NC}"
FAILURE="${RED}FAILED${NC}"
WARNING="${YELLOW}[WARNING]${NC}"
SKIPPED="${YELLOW}SKIPPED${NC}"
SUCCESS="${GREEN}ok${NC}"

printf "${PREFIX} Clean working copy ... "
git diff --exit-code &>/dev/null
if [ "$?" == 0 ]; then
	printf "${SUCCESS}\n"
else
	if [ "${TARPC_ALLOW_DIRTY}" == "1" ]
	then
		printf "${SKIPPED}\n"
	else
		printf "${FAILURE}\n"
		exit 1
	fi
fi

PREPUSH_RESULT=0

# args:
# 1 - cargo command to run (build/test)
# 2 - rust toolchain (nightly/stable/beta)
run_cargo() {
	if [ "$1" == "build" ]; then
		VERB=Building
	else
		VERB=Testing
	fi
	if [ "$2" != "" ]; then
		printf "${PREFIX} $VERB on $2... "
                if [ "$2" != "nightly" ]; then
                    rustup run $2 cargo $1 &>/dev/null
                else
                    rustup run nightly cargo $1 --features unstable &>/dev/null
                fi
	else
		printf "${PREFIX} $VERB... "
		cargo $1 &>/dev/null
	fi
	if [ "$?" != "0" ]; then
		printf "${FAILURE}\n"
		PREPUSH_RESULT=1
	else
		printf "${SUCCESS}\n"
	fi
}

TOOLCHAIN_RESULT=0
check_toolchain() {
	printf "${PREFIX} Checking for $1 toolchain ... "
	if [[ $(rustup toolchain list) =~ $1 ]]; then
		printf "${SUCCESS}\n"
	else
		TOOLCHAIN_RESULT=1
		PREPUSH_RESULT=1
		printf "${FAILURE}\n"
	fi
}

printf "${PREFIX} Checking for rustup or current toolchain directive... "
command -v rustup &>/dev/null
if [ "$?" == 0 ] && [ "${TARPC_USE_CURRENT_TOOLCHAIN}" == "" ]; then
	printf "${SUCCESS}\n"

	check_toolchain stable
	check_toolchain beta
	check_toolchain nightly
	if [ ${TOOLCHAIN_RESULT} == 1 ]; then
		exit 1
	fi

	run_cargo build stable
	run_cargo build beta
	run_cargo build nightly

	# We still rely on some nightly stuff for tests
	run_cargo test nightly
else
        if [ "${TARPC_USE_CURRENT_TOOLCHAIN}" == "" ]; then
              printf "${YELLOW}NOT FOUND${NC}\n"
              printf "${WARNING} Falling back to current toolchain: $(rustc -V)\n"
        else
              printf "${SUCCESS}\n"
        fi

    run_cargo build
	run_cargo test
fi

exit $PREPUSH_RESULT