#!/bin/bash
warned=0
final_ret=0

# Check for ruby binary
which ruby >/dev/null 2>&1
if [[ $? -ne 0 ]]; then
    echo "Ruby not found" 1>&2
    exit 1
fi

# Check for Puppet binary
which puppet >/dev/null 2>&1
if [[ $? -ne 0 ]]; then
    echo "Puppet not found" 1>&2
    exit 1
fi

# Check for puppet-lint
which puppet-lint >/dev/null 2>&1
if [[ $? -ne 0 ]]; then
    echo "puppet-lint not found" 1>&2
    exit 1
fi

# Check for erb
which erb >/dev/null 2>&1
if [[ $? -ne 0 ]]; then
    echo "erb not found" 1>&2
    exit 1
fi

if [[ "x${HOME}" == "x" ]]; then
    id=`whoami`
    HOME=`eval echo ~${id}`
    export HOME
fi

styleguide_url='http://docs.puppetlabs.com/guides/style_guide.html'
git cat-file -e $newrev:.puppetstyle.url >/dev/null 2>&1
if [[ $? -eq 0 ]]; then
    styleguide_url=$(git show $newrev:.puppetstyle.url)
fi

tmpdir=`mktemp -d`
tmpfile="$tmpdir/candidate"

while read oldrev newrev refname; do
    # Grab a copy of .puppet-lint.rc from this ref if it exists,
    # and use it to disable lint checks
    # puppet-lint > 1.0 will let us choose a unique location for the config file
    # for now we're dropping it into git bare .git repo, non-fatal race condition
    git cat-file -e $newrev:.puppet-lint.rc && git show $newrev:.puppet-lint.rc > .puppet-lint.rc

    # Retrieve a list of all modified files as part of this push
    # We'll only check the latest revisionso that things that were broken but then fixed
    # can be pushed. As such, strip out any duplicates, where the same file was changed
    # in multiple commits
    for puppetmodule in `git diff-tree --no-commit-id --diff-filter=ACM --name-only -r "$oldrev" "$newrev" | sort | uniq`; do

        # Retrieve the latest version of the changed file
        git show $newrev:$puppetmodule > $tmpfile
        case $puppetmodule in
            *.pp ) 
                puppet parser validate $tmpfile
                rc=$?
                if [[ $rc != 0 ]]; then
                    echo -e "\e[0;31m'puppet parser validate' failed on $puppetmodule - push denied. Run tests locally and confirm they pass before pushing. \e[0m"
                    final_ret=1
                fi
                puppet-lint $tmpfile
                rc=$?
                if [[ $rc != 0 ]]; then
                    if [[ $warned = 0 ]]; then
                        echo -e "\e[0;33m" "Please follow the puppet module styleguide (${styleguide_url})." "\e[0m"
                        echo -e "\e[0;33m" "The above ERROR/WARNING messages are informational only. The commit has not been blocked for this reason. In the future, these may cause your commit to be refused." "\e[0m"
                        warned=1
                    fi
                    echo -e "\e[0;33m" "Style guide compliance errors in $puppetmodule:" "\e[0m"
                fi
                ;;
            *.erb )
                cat $tmpfile | erb -x -T - | ruby -c 2>&1 >/dev/null
                rc=$?
                if [[ $rc != 0 ]]; then
                    echo -e "\e[0;31m" "Ruby syntax checker failed on template $puppetmodule:" "\e[0m"
                    final_ret=1
                fi
                ;;
            *.yml|*.yaml)
                # syntax YAML files, https://ttboj.wordpress.com/2013/08/25/finding-yaml-errors-in-puppet/
                ruby -ryaml -e "YAML.parse(File.open('${tmpfile}'))"
                if [[ $? -ne 0 ]]; then
                    echo -e "\e[0;31m" "YAML syntax error in ${puppetmodule}" "\e[0m"
                    final_ret=1
                fi
            ;;
            *.json)
                ruby -rrubygems -e "require 'json'; JSON.parse(File.open('${tmpfile}').read)"
                if [[ $? -ne 0 ]]; then
                    echo -e "\e[0;31m" "JSON syntax error in ${puppetmodule}" "\e[0m"
                    final_ret=1
                fi
            ;;
        esac
    done
done

rm -rf $tmpdir

exit $final_ret