#!/bin/bash

VCS_SUPPORTED="GIT, Subversion or Mercurial"

print_usage()
{
    echo "$(basename $0) -- diff for version control (${VCS_SUPPORTED}) with color output."
    echo "Usage: $(basename $0) [OPTIONS...]"
}

if [ "x${1}" = "x--help" ]; then
    print_usage
    exit 1
fi

if git diff 1> /dev/null 2>&1; then
    git diff "$@"
elif svn diff 1> /dev/null 2>&1; then
    svn diff --diff-cmd colordiff -x "-u -w -p" "$@" | less -RFX
elif hg status 1> /dev/null 2>&1; then
    hg diff "$@"
else
    echo "Not a ${VCS_SUPPORTED} repository"
    exit 1
fi