#!/bin/bash
# Copyright (c) 2011 The Chromium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

# mass-rename: update source files (gyp lists, #includes) to reflect
# a rename.  Expects "git diff --cached -M" to list a bunch of renames.
#
# To use:
#   1) git mv foo1 bar1; git mv foo2 bar2; etc.
#   2) *without committing*, ./tools/git/mass-rename.sh
#   3) look at git diff (without --cached) to see what the damage is
#   4) commit, then use tools/sort-headers.py to fix #include ordering:
#   for f in $(git diff --name-only origin); do ./tools/sort-headers.py $f; done

# rename:
# update all uses of |from| (first argument) to |to| (second argument).
rename() {
    from="$1"
    to="$2"

    # Fix references to the files in headers/gyp files.
    echo "Processing: $from -> $to"
    git grep -l "$from" -- '*.cc' '*.h' '*.m' '*.mm' '*.gyp*' | \
        xargs sed -i -e "s|$from|$to|"

    # Fix header guards.
    if [ "${from##*.}" = "h" ]; then
        hfrom=$(echo "$from" | tr 'a-z/' 'A-Z_' | sed -e 's|\..*$||')
        hto=$(echo "$to" | tr 'a-z/' 'A-Z_' | sed -e 's|\..*$||')
        echo "Processing: $hfrom -> $hto"
        git grep -l "$hfrom" -- '*.cc' '*.h' '*.m' '*.mm' | \
            xargs sed -i -e "s|$hfrom|$hto|"
    fi

    # Try again, stripping the first directory component -- helps with
    # gyp files that rely on paths from the directory they're in.
    from=$(echo "$from" | sed -e 's|^[^/]*/||')
    to=$(echo "$to" | sed -e 's|^[^/]*/||')
    echo "Processing: $from -> $to"
    git grep -l "$from" -- '*.cc' '*.h' '*.m' '*.mm' '*.gyp*' | \
        xargs sed -i -e "s|$from|$to|"
}

# Make the 'read' used in the while loop split only on tabs/newlines.
IFS=$'\t\n'

git diff --cached --raw -M | while read attrs from to; do
    type=$(echo "$attrs" | cut -d' ' -f5)
    if echo "$type" | grep -q "^R"; then
        # It's a rename.
        rename "$from" "$to"
    else
        echo "Skipping: $from -- not a rename?"
    fi
done