#!/bin/sh

case "$1" in
        --help)
                echo "usage: $0 [--config file] [other_git_tree...] [--] [test_scripts]"
                exit 0
                ;;
        --config)
                shift
                GIT_PERF_CONFIG_FILE=$(cd "$(dirname "$1")"; pwd)/$(basename "$1")
                export GIT_PERF_CONFIG_FILE
                shift ;;
esac

die () {
        echo >&2 "error: $*"
        exit 1
}

run_one_dir () {
        if test $# -eq 0; then
                set -- p????-*.sh
        fi
        echo "=== Running $# tests in ${GIT_TEST_INSTALLED:-this tree} ==="
        for t in "$@"; do
                ./$t $GIT_TEST_OPTS
        done
}

unpack_git_rev () {
        rev=$1
        echo "=== Unpacking $rev in build/$rev ==="
        mkdir -p build/$rev
        (cd "$(git rev-parse --show-cdup)" && git archive --format=tar $rev) |
        (cd build/$rev && tar x)
}

build_git_rev () {
        rev=$1
        name="$2"
        for config in config.mak config.mak.autogen config.status
        do
                if test -e "../../$config"
                then
                        cp "../../$config" "build/$rev/"
                fi
        done
        echo "=== Building $rev ($name) ==="
        (
                cd build/$rev &&
                if test -n "$GIT_PERF_MAKE_COMMAND"
                then
                        sh -c "$GIT_PERF_MAKE_COMMAND"
                else
                        make $GIT_PERF_MAKE_OPTS
                fi
        ) || die "failed to build revision '$mydir'"
}

run_dirs_helper () {
        mydir=${1%/}
        shift
        while test $# -gt 0 -a "$1" != -- -a ! -f "$1"; do
                shift
        done
        if test $# -gt 0 -a "$1" = --; then
                shift
        fi
        if [ ! -d "$mydir" ]; then
                rev=$(git rev-parse --verify "$mydir" 2>/dev/null) ||
                die "'$mydir' is neither a directory nor a valid revision"
                if [ ! -d build/$rev ]; then
                        unpack_git_rev $rev
                fi
                build_git_rev $rev "$mydir"
                mydir=build/$rev
        fi
        if test "$mydir" = .; then
                unset GIT_TEST_INSTALLED
        else
                GIT_TEST_INSTALLED="$mydir/bin-wrappers"
                # Older versions of git lacked bin-wrappers; fallback to the
                # files in the root.
                test -d "$GIT_TEST_INSTALLED" || GIT_TEST_INSTALLED=$mydir
                export GIT_TEST_INSTALLED
        fi
        run_one_dir "$@"
}

run_dirs () {
        while test $# -gt 0 -a "$1" != -- -a ! -f "$1"; do
                run_dirs_helper "$@"
                shift
        done
}

get_subsections () {
        section="$1"
        test -z "$GIT_PERF_CONFIG_FILE" && return
        git config -f "$GIT_PERF_CONFIG_FILE" --name-only --get-regex "$section\..*\.[^.]+" |
        sed -e "s/$section\.\(.*\)\..*/\1/" | sort | uniq
}

get_var_from_env_or_config () {
        env_var="$1"
        conf_sec="$2"
        conf_var="$3"
        # $4 can be set to a default value

        # Do nothing if the env variable is already set
        eval "test -z \"\${$env_var+x}\"" || return

        test -z "$GIT_PERF_CONFIG_FILE" && return

        # Check if the variable is in the config file
        if test -n "$GIT_PERF_SUBSECTION"
        then
                var="$conf_sec.$GIT_PERF_SUBSECTION.$conf_var"
                conf_value=$(git config -f "$GIT_PERF_CONFIG_FILE" "$var") &&
                eval "$env_var=\"$conf_value\"" && return
        fi
        var="$conf_sec.$conf_var"
        conf_value=$(git config -f "$GIT_PERF_CONFIG_FILE" "$var") &&
        eval "$env_var=\"$conf_value\"" && return

        test -n "${4+x}" && eval "$env_var=\"$4\""
}

run_subsection () {
        get_var_from_env_or_config "GIT_PERF_REPEAT_COUNT" "perf" "repeatCount" 3
        export GIT_PERF_REPEAT_COUNT

        get_var_from_env_or_config "GIT_PERF_DIRS_OR_REVS" "perf" "dirsOrRevs"
        set -- $GIT_PERF_DIRS_OR_REVS "$@"

        get_var_from_env_or_config "GIT_PERF_MAKE_COMMAND" "perf" "makeCommand"
        get_var_from_env_or_config "GIT_PERF_MAKE_OPTS" "perf" "makeOpts"

        GIT_PERF_AGGREGATING_LATER=t
        export GIT_PERF_AGGREGATING_LATER

        if test $# = 0 -o "$1" = -- -o -f "$1"; then
                set -- . "$@"
        fi

        run_dirs "$@"
        ./aggregate.perl "$@"
}

cd "$(dirname $0)"
. ../../GIT-BUILD-OPTIONS

mkdir -p test-results
get_subsections "perf" >test-results/run_subsections.names

if test $(wc -l <test-results/run_subsections.names) -eq 0
then
        (
                run_subsection "$@"
        )
else
        while read -r subsec
        do
                (
                        GIT_PERF_SUBSECTION="$subsec"
                        export GIT_PERF_SUBSECTION
                        echo "======== Run for subsection '$GIT_PERF_SUBSECTION' ========"
                        run_subsection "$@"
                )
        done <test-results/run_subsections.names
fi