#!/bin/bash

export EDITOR="$GIT_REBASE_I_EDITOR"

tempfile="$(tempfile)"

if ! (cat "$1" | grep -q "Rebase .* onto .* (.* command(s))"); then
    exec editor "$@"
fi

# how can I get the --graph with only the desired commits?

cat "$1" \
    | sed -n -e '/^pick/ s/pick \([^ ]*\) .*$/\1/ p' \
    | tac \
    | xargs -n 1 git log -1 --oneline --decorate --graph --name-status \
    | sed -e 's~^\* \([0-9a-f][0-9a-f]* \)~pick \1~' \
            > "$tempfile"

# with --graph, if there are actually any pipes, use:
# | sed -e 's~^\([ |\\/*]* \)\([0-9a-f][0-9a-f]* \)~\1pick \2~' \

echo >> "$tempfile"
echo "# Originial git rebase -i data:" >> "$tempfile"
cat "$1" | sed -e 's/^/#/' >> "$tempfile"

editor "$tempfile"

# p, pick
# r, reword
# e, edit
# s, squash
# f, fixup
# x, exec
# d, drop

commands='p\|pick\|r\|reword\|e\|edit\|s\|squash\|f\|fixup\|x\|exec\|d\|drop'

cat "$tempfile" \
    | grep -v "^#" \
    | grep -v "^ *[|\\/][ |\\/]*[^|\\/*]" \
    | tac \
    | sed -e 's~^\([ |\\/*]* \)\(\('"$commands"'\)[0-9a-f][0-9a-f]* \)~\2~' \
    | tee "$1" >&2