groovy-core/src/main/org/codehaus/groovy/tools/shell/util/HelpFormatter.groovy

/*
 * Copyright 2003-2007 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.codehaus.groovy.tools.shell.util

import jline.Terminal

import org.apache.commons.cli.Options

//
// NOTE: Some code duplicated and augumented from commons-cli (1.0) sources to
//       properly render options w/arguments.
//


/**
 * Custom CLI help formatter to render things correctly.
 *
 * @version $Id$
 * @author <a href="mailto:jason@planet57.com">Jason Dillon</a>
 */
class HelpFormatter
    extends org.apache.commons.cli.HelpFormatter
{
    HelpFormatter() {
        defaultLeftPad = 2
        defaultDescPad = 4
    }

    // Detect the terminal width late
    public int getDefaultWidth() {
        return Terminal.terminal.terminalWidth - 1
    }

    protected StringBuffer renderOptions(final StringBuffer sb, final int width, final Options options, final int leftPad, final int descPad) {
        assert sb != null
        assert options
        
        List prefixes = []
        String lpad = ' ' * leftPad
        
        List opts = options.shortOpts.values().sort { a, b ->
            return (a.opt == ' ' ? a.longOpt : a.opt) <=> (b.opt == ' ' ? b.longOpt : b.opt)
        }
        
        // Render the prefixes (-X,--xxxx muck)
        opts.each { option ->
            def buff = new StringBuffer(8)
            
            if (option.opt == ' ') {
                buff << "${lpad}    ${defaultLongOptPrefix}${option.longOpt}"
            }
            else {
                buff << "${lpad}${defaultOptPrefix}${option.opt}"
                
                if (option.hasLongOpt()) {
                    buff << ", ${defaultLongOptPrefix}${option.longOpt}"
                }
            }
            
            if (option.hasArg()) {
                if (option.hasArgName()) {
                    if (option.hasOptionalArg()) {
                        buff << "[=${option.argName}]"
                    }
                    else {
                        buff << "=${option.argName}"
                    }
                }
                else {
                    buff << ' '
                }
            }
            
            prefixes << buff
        }
        
        // Figure out how long the biggest prefix is
        int maxPrefix = prefixes.max { a, b -> a.size() <=> b.size() }.size()
        
        String dpad = ' ' * descPad
        
        // And then render each option's prefix with its description
        opts.eachWithIndex { option, i ->
            def buff = new StringBuffer(prefixes[i].toString())
            
            if (buff.size() < maxPrefix) {
                buff << ' ' * (maxPrefix - buff.size())
            }
            buff << dpad
            
            int nextLineTabStop = maxPrefix + descPad
            String text = buff << option.description
            
            renderWrappedText(sb, width, nextLineTabStop, text)
            
            if (i < opts.size() - 1) {
                sb << defaultNewLine
            }
        }
        
        return sb
    }
}