#!/bin/sh

TRUNK_HASH=`git show-ref --hash remotes/trunk`
REV=`git svn find-rev "$TRUNK_HASH"`

if [ "$#" -eq 0 ]
then
	HASHES="$TRUNK_HASH..HEAD"
else
	HASHES="$1"
fi

INDEX_SEPARATOR="==================================================================="
SRC_PREFIX="REVIEWBOARD-SRC-PREFIX"
DST_PREFIX="REVIEWBOARD-DST-PREFIX"

# Note: removed the $* to support passing a hash as the first argument
git diff --src-prefix="${SRC_PREFIX}" --dst-prefix="${DST_PREFIX}" "$HASHES" |
sed "
# New files have /dev/null as their original path
/^--- \/dev\/null/{
    # Read a line into the pattern space
    N
    # Do a multiline substitution
    s/^--- \/dev\/null\n+++ ${DST_PREFIX}\(.*\)$/--- \1\t(revision 0)\n+++ \1\t (working copy)/
    # Jump to the end of the script. This skips the next two substitutions
    b end
}
/^diff --git /{
    # Read a line into the pattern space
    N
    # In case there is no 'new file mode' line
    /^diff --git ${SRC_PREFIX}\(.*\) ${DST_PREFIX}.*\nindex .*$/{
        s/^diff --git ${SRC_PREFIX}\(.*\) ${DST_PREFIX}.*\nindex .*$/Index: \1\n${INDEX_SEPARATOR}/
	b end
    }
    # There is a 'new file mode' line
    # Read a third line
    N
    # In case there is a 'new file mode' line
    /^diff --git ${SRC_PREFIX}\(.*\) ${DST_PREFIX}.*\nnew file mode .*\nindex .*$/{
        # Do a multiline substitution
        s/^diff --git ${SRC_PREFIX}\(.*\) ${DST_PREFIX}.*\nnew file mode .*\nindex .*$/Index: \1\n${INDEX_SEPARATOR}/
        b end
    }
    # In case there is a 'deleted file mode' line
    /^diff --git ${SRC_PREFIX}\(.*\) ${DST_PREFIX}.*\ndeleted file mode .*\nindex .*$/{
        # Do a multiline substitution
        s/^diff --git ${SRC_PREFIX}\(.*\) ${DST_PREFIX}.*\ndeleted file mode .*\nindex .*$/Index: \1\n${INDEX_SEPARATOR}/
        b end
    }
    # There is an 'old mode' line
    # Read a forth line
    N
    # Do a multiline substitution
    s/^diff --git ${SRC_PREFIX}\(.*\) ${DST_PREFIX}.*\nold mode .*\nnew mode .*\nindex .*$/Index: \1\n${INDEX_SEPARATOR}/
    b end

}
/^--- ${SRC_PREFIX}\(.*\)/{
    # Read a line into the pattern space
    N
    # Do a multiline substitution
    s/^--- ${SRC_PREFIX}\(.*\)\n+++ .*$/--- \1\t(revision ${REV})\n+++ \1\t (working copy)/
    # Jump to the end of the script. This skips the next two substitutions
    b end
}
: end
"