#!/bin/sh
set -e

if [ $# -lt 1 ]; then
    argv0=`basename $0`
    echo "$argv0: Convert source code written for Xr to use Cairo instead." >&2
    echo "" >&2
    echo "Usage: $argv0 file [...]" >&2
    exit 1
fi

xr2cairo() {
	file=$1
	backup=$file.xr

	if [ -e $backup ]; then
		echo "Warning: Backup file $backup already exists --- not backing up this time." >&2
	else
		cp $file $backup
	fi
	sed -e '
		s/\(Xr[a-zA-Z]*\)RGB/\1Rgb/g
		s/\(Xr[a-zA-Z]*\)NextTo/\1Similar/g

		s/Xr\([A-Z]\+[a-z]\+\)\([A-Z]\+[a-z]\+\)\([A-Z]\+[a-z]\+\)\([A-Z]\+[a-z]\+\)\([A-Z]\+[a-z]\+\)/\Lcairo_\1_\2_\3_\4_\5\E/g
		s/Xr\([A-Z]\+[a-z]\+\)\([A-Z]\+[a-z]\+\)\([A-Z]\+[a-z]\+\)\([A-Z]\+[a-z]\+\)/\Lcairo_\1_\2_\3_\4\E/g
		s/Xr\([A-Z]\+[a-z]\+\)\([A-Z]\+[a-z]\+\)\([A-Z]\+[a-z]\+\)/\Lcairo_\1_\2_\3\E/g
		s/Xr\([A-Z]\+[a-z]\+\)\([A-Z]\+[a-z0-9]\+\)/\Lcairo_\1_\2\E/g
		s/Xr\([A-Z]\+[a-z]\+\)/\Lcairo_\1\E/g

		s/\(cairo_\(operator\|status\|fill_rule\|line_cap\|line_join\|filter\|format\)_[a-z0-9_]\{2,\}\)/\U\1/g

		s/cairo_\(fill_rule\|line_cap\|line_join\|format\|operator\|status\|filter\|surface\|matrix\)$/cairo_\1_t/g
		s/cairo_\(fill_rule\|line_cap\|line_join\|format\|operator\|status\|filter\|surface\|matrix\)\([^_]\)/cairo_\1_t\2/g
		s/_cairo_\(fill_rule\|line_cap\|line_join\|format\|operator\|status\|filter\|surface\|matrix\)_t/cairo_\1/g
		s/cairo_state/cairo_t/g
		s/_cairo_t\([^a-zA-Z0-9_]\)/cairo\1/g

		s/Xr\.h/cairo.h/g

		' $backup > $file
}

while [ $# -gt 0 ]; do
	file=$1
	shift
	xr2cairo $file
done