#!/bin/sh

USAGE='[help|start|bad|good|new|old|terms|skip|next|reset|visualize|view|replay|log|run]'
LONG_USAGE='git bisect help
        print this long help message.
git bisect start [--term-{old,good}=<term> --term-{new,bad}=<term>]
                 [--no-checkout] [<bad> [<good>...]] [--] [<pathspec>...]
        reset bisect state and start bisection.
git bisect (bad|new) [<rev>]
        mark <rev> a known-bad revision/
                a revision after change in a given property.
git bisect (good|old) [<rev>...]
        mark <rev>... known-good revisions/
                revisions before change in a given property.
git bisect terms [--term-good | --term-bad]
        show the terms used for old and new commits (default: bad, good)
git bisect skip [(<rev>|<range>)...]
        mark <rev>... untestable revisions.
git bisect next
        find next bisection to test and check it out.
git bisect reset [<commit>]
        finish bisection search and go back to commit.
git bisect (visualize|view)
        show bisect status in gitk.
git bisect replay <logfile>
        replay bisection log.
git bisect log
        show bisect log.
git bisect run <cmd>...
        use <cmd>... to automatically bisect.

Please use "git help bisect" to get the full man page.'

OPTIONS_SPEC=
. git-sh-setup

_x40='[0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f]'
_x40="$_x40$_x40$_x40$_x40$_x40$_x40$_x40$_x40"
TERM_BAD=bad
TERM_GOOD=good

bisect_head()
{
        if test -f "$GIT_DIR/BISECT_HEAD"
        then
                echo BISECT_HEAD
        else
                echo HEAD
        fi
}

bisect_autostart() {
        test -s "$GIT_DIR/BISECT_START" || {
                gettextln "You need to start by \"git bisect start\"" >&2
                if test -t 0
                then
                        # TRANSLATORS: Make sure to include [Y] and [n] in your
                        # translation. The program will only accept English input
                        # at this point.
                        gettext "Do you want me to do it for you [Y/n]? " >&2
                        read yesno
                        case "$yesno" in
                        [Nn]*)
                                exit ;;
                        esac
                        bisect_start
                else
                        exit 1
                fi
        }
}

bisect_start() {
        git bisect--helper --bisect-start $@ || exit

        #
        # Change state.
        # In case of mistaken revs or checkout error, or signals received,
        # "bisect_auto_next" below may exit or misbehave.
        # We have to trap this to be able to clean up using
        # "bisect_clean_state".
        #
        trap 'git bisect--helper --bisect-clean-state' 0
        trap 'exit 255' 1 2 3 15

        #
        # Check if we can proceed to the next bisect state.
        #
        get_terms
        bisect_auto_next

        trap '-' 0
}

bisect_skip() {
        all=''
        for arg in "$@"
        do
                case "$arg" in
                *..*)
                        revs=$(git rev-list "$arg") || die "$(eval_gettext "Bad rev input: \$arg")" ;;
                *)
                        revs=$(git rev-parse --sq-quote "$arg") ;;
                esac
                all="$all $revs"
        done
        eval bisect_state 'skip' $all
}

bisect_state() {
        bisect_autostart
        state=$1
        git bisect--helper --check-and-set-terms $state $TERM_GOOD $TERM_BAD || exit
        get_terms
        case "$#,$state" in
        0,*)
                die "Please call 'bisect_state' with at least one argument." ;;
        1,"$TERM_BAD"|1,"$TERM_GOOD"|1,skip)
                bisected_head=$(bisect_head)
                rev=$(git rev-parse --verify "$bisected_head") ||
                        die "$(eval_gettext "Bad rev input: \$bisected_head")"
                git bisect--helper --bisect-write "$state" "$rev" "$TERM_GOOD" "$TERM_BAD" || exit
                git bisect--helper --check-expected-revs "$rev" ;;
        2,"$TERM_BAD"|*,"$TERM_GOOD"|*,skip)
                shift
                hash_list=''
                for rev in "$@"
                do
                        sha=$(git rev-parse --verify "$rev^{commit}") ||
                                die "$(eval_gettext "Bad rev input: \$rev")"
                        hash_list="$hash_list $sha"
                done
                for rev in $hash_list
                do
                        git bisect--helper --bisect-write "$state" "$rev" "$TERM_GOOD" "$TERM_BAD" || exit
                done
                git bisect--helper --check-expected-revs $hash_list ;;
        *,"$TERM_BAD")
                die "$(eval_gettext "'git bisect \$TERM_BAD' can take only one argument.")" ;;
        *)
                usage ;;
        esac
        bisect_auto_next
}

bisect_auto_next() {
        git bisect--helper --bisect-next-check $TERM_GOOD $TERM_BAD && bisect_next || :
}

bisect_next() {
        case "$#" in 0) ;; *) usage ;; esac
        bisect_autostart
        git bisect--helper --bisect-next-check $TERM_GOOD $TERM_BAD $TERM_GOOD|| exit

        # Perform all bisection computation, display and checkout
        git bisect--helper --next-all $(test -f "$GIT_DIR/BISECT_HEAD" && echo --no-checkout)
        res=$?

        # Check if we should exit because bisection is finished
        if test $res -eq 10
        then
                bad_rev=$(git show-ref --hash --verify refs/bisect/$TERM_BAD)
                bad_commit=$(git show-branch $bad_rev)
                echo "# first $TERM_BAD commit: $bad_commit" >>"$GIT_DIR/BISECT_LOG"
                exit 0
        elif test $res -eq 2
        then
                echo "# only skipped commits left to test" >>"$GIT_DIR/BISECT_LOG"
                good_revs=$(git for-each-ref --format="%(objectname)" "refs/bisect/$TERM_GOOD-*")
                for skipped in $(git rev-list refs/bisect/$TERM_BAD --not $good_revs)
                do
                        skipped_commit=$(git show-branch $skipped)
                        echo "# possible first $TERM_BAD commit: $skipped_commit" >>"$GIT_DIR/BISECT_LOG"
                done
                exit $res
        fi

        # Check for an error in the bisection process
        test $res -ne 0 && exit $res

        return 0
}

bisect_visualize() {
        git bisect--helper --bisect-next-check $TERM_GOOD $TERM_BAD fail || exit

        if test $# = 0
        then
                if test -n "${DISPLAY+set}${SESSIONNAME+set}${MSYSTEM+set}${SECURITYSESSIONID+set}" &&
                        type gitk >/dev/null 2>&1
                then
                        set gitk
                else
                        set git log
                fi
        else
                case "$1" in
                git*|tig) ;;
                -*)     set git log "$@" ;;
                *)      set git "$@" ;;
                esac
        fi

        eval '"$@"' --bisect -- $(cat "$GIT_DIR/BISECT_NAMES")
}

bisect_replay () {
        file="$1"
        test "$#" -eq 1 || die "$(gettext "No logfile given")"
        test -r "$file" || die "$(eval_gettext "cannot read \$file for replaying")"
        git bisect--helper --bisect-reset || exit
        while read git bisect command rev
        do
                test "$git $bisect" = "git bisect" || test "$git" = "git-bisect" || continue
                if test "$git" = "git-bisect"
                then
                        rev="$command"
                        command="$bisect"
                fi
                get_terms
                git bisect--helper --check-and-set-terms "$command" "$TERM_GOOD" "$TERM_BAD" || exit
                get_terms
                case "$command" in
                start)
                        cmd="bisect_start $rev"
                        eval "$cmd" ;;
                "$TERM_GOOD"|"$TERM_BAD"|skip)
                        git bisect--helper --bisect-write "$command" "$rev" "$TERM_GOOD" "$TERM_BAD" || exit;;
                terms)
                        git bisect--helper --bisect-terms $rev || exit;;
                *)
                        die "$(gettext "?? what are you talking about?")" ;;
                esac
        done <"$file"
        bisect_auto_next
}

bisect_run () {
        git bisect--helper --bisect-next-check $TERM_GOOD $TERM_BAD fail || exit

        test -n "$*" || die "$(gettext "bisect run failed: no command provided.")"

        while true
        do
                command="$@"
                eval_gettextln "running \$command"
                "$@"
                res=$?

                # Check for really bad run error.
                if [ $res -lt 0 -o $res -ge 128 ]
                then
                        eval_gettextln "bisect run failed:
exit code \$res from '\$command' is < 0 or >= 128" >&2
                        exit $res
                fi

                # Find current state depending on run success or failure.
                # A special exit code of 125 means cannot test.
                if [ $res -eq 125 ]
                then
                        state='skip'
                elif [ $res -gt 0 ]
                then
                        state="$TERM_BAD"
                else
                        state="$TERM_GOOD"
                fi

                # We have to use a subshell because "bisect_state" can exit.
                ( bisect_state $state >"$GIT_DIR/BISECT_RUN" )
                res=$?

                cat "$GIT_DIR/BISECT_RUN"

                if sane_grep "first $TERM_BAD commit could be any of" "$GIT_DIR/BISECT_RUN" \
                        >/dev/null
                then
                        gettextln "bisect run cannot continue any more" >&2
                        exit $res
                fi

                if [ $res -ne 0 ]
                then
                        eval_gettextln "bisect run failed:
'bisect_state \$state' exited with error code \$res" >&2
                        exit $res
                fi

                if sane_grep "is the first $TERM_BAD commit" "$GIT_DIR/BISECT_RUN" >/dev/null
                then
                        gettextln "bisect run success"
                        exit 0;
                fi

        done
}

bisect_log () {
        test -s "$GIT_DIR/BISECT_LOG" || die "$(gettext "We are not bisecting.")"
        cat "$GIT_DIR/BISECT_LOG"
}

get_terms () {
        if test -s "$GIT_DIR/BISECT_TERMS"
        then
                {
                read TERM_BAD
                read TERM_GOOD
                } <"$GIT_DIR/BISECT_TERMS"
        fi
}

case "$#" in
0)
        usage ;;
*)
        cmd="$1"
        get_terms
        shift
        case "$cmd" in
        help)
                git bisect -h ;;
        start)
                bisect_start "$@" ;;
        bad|good|new|old|"$TERM_BAD"|"$TERM_GOOD")
                bisect_state "$cmd" "$@" ;;
        skip)
                bisect_skip "$@" ;;
        next)
                # Not sure we want "next" at the UI level anymore.
                bisect_next "$@" ;;
        visualize|view)
                bisect_visualize "$@" ;;
        reset)
                git bisect--helper --bisect-reset "$@" ;;
        replay)
                bisect_replay "$@" ;;
        log)
                bisect_log ;;
        run)
                bisect_run "$@" ;;
        terms)
                git bisect--helper --bisect-terms "$@" || exit;;
        *)
                usage ;;
        esac
esac