grammar Dto;

// http://www.cs.usfca.edu/~parrt/course/652/lectures/antlr.html
// Good introduction, though some of it is applicable only to ANTLR 2.
// The section on actions is good, though, and the section on ASTs is OK.
// 
// @author Daniel Gredler

@header {
	import java.io.*;
	import java.util.Date;
	import java.util.Iterator;
	import java.util.regex.*;
	import java.text.SimpleDateFormat;
}

@members {

	// Main: process all the files in the "input" directory, write results to the "output" directory.
	public static void main(String[] args) throws Exception {
		File input = new File("input");
		File output = new File("output");
		for (File file : input.listFiles()) {
			if(file.getName().startsWith(".")) {
				continue;
			}
			DtoLexer lex = new DtoLexer(new ANTLRFileStream(file.getAbsolutePath()));
			CommonTokenStream tokens = new CommonTokenStream(lex);
			DtoParser parser = new DtoParser(tokens);
			try {
				Clazz c = parser.clazz();
				writeStringToFile(toJavaDto(c), new File(output, c.name + ".java"));
				writeStringToFile(toJavaTest(c), new File(output, c.name + "Test.java"));
			} catch (RecognitionException e)  {
				e.printStackTrace();
			}
		}
	}

	private static void writeStringToFile(String s, File f) {
		try {
			BufferedWriter writer = new BufferedWriter(new FileWriter(f));
			writer.write(s);
			writer.close();
		} catch(IOException e) {
			e.printStackTrace();
		}
	}

	private static String toJavaTest(Clazz c) {
		// Start things up.
		StringBuilder s = new StringBuilder();
		addHeader(s);
		addPackage(s, c.pkg);
		for(Iterator i = c.props.iterator(); i.hasNext(); ) {
			Property p = (Property) i.next();
			s.append("import static com.mycompany.myproject.").append(c.pkg).append(".facade.dto.").append(c.name).append(".").append(p.uuname).append(";\r\n");
		}
		s.append("\r\n");
		addClassJavaDoc(s, "Unit tests for {@link " + c.name + "}.");
		s.append("public class ").append(c.name).append("Test extends TestCase {\r\n\r\n");
		// Add the setter and getter testing.
		s.append("    /**\r\n");
		s.append("     * Tests all the setters and getters, including whether or not they fire property change events.\r\n");
		s.append("     * @throws Exception if an error occurs\r\n");
		s.append("     */\r\n");
		s.append("    public void testSettersAndGetters() throws Exception {\r\n");
		s.append("        SetterGetterTester t = new SetterGetterTester(").append(c.name).append(".class);\r\n");
		s.append("        // TODO: change the initial and alternate values for all the properties.\r\n");
		for(Iterator i = c.props.iterator(); i.hasNext(); ) {
			Property p = (Property) i.next();
			s.append("        t.testProperty(").append(p.uuname).append(", false, null, null);\r\n");
		}
		s.append("    }\r\n\r\n");
		// Add the hashCode() and equals() testing.
		s.append("    /**\r\n");
		s.append("     * Tests the <tt>equals()</tt>, <tt>hashCode()</tt> and <tt>toString()</tt> methods.\r\n");
		s.append("     * @throws Exception if an error occurs\r\n");
		s.append("     */\r\n");
		s.append("    public void testEqualsAndHashcode() throws Exception {\r\n");
		s.append("        new EqualsHashCodeTester(").append(c.name).append(".class");
		for(Iterator i = c.props.iterator(); i.hasNext(); ) {
			Property p = (Property) i.next();
			if(p.biz) {
				s.append(", ").append(p.uuname);
			}
		}
		s.append(").test();\r\n");
		s.append("    }\r\n\r\n");
		// Finish things up.
		s.append("}\r\n");
		return s.toString();
	}

	private static String toJavaDto(Clazz c) {
		// Start things up.
		StringBuilder s = new StringBuilder();
		addHeader(s);
		addPackage(s, c.pkg);
		addClassJavaDoc(s, "TODO: class description");
		s.append("public class ").append(c.name).append(" extends AbstractDto {\r\n\r\n");
		s.append("    // TODO: generate serialVersionUID\r\n\r\n");
		// Add property name constants.
		for(Iterator i = c.props.iterator(); i.hasNext(); ) {
			Property p = (Property) i.next();
			s.append("    /** The property name for ").append(p.desc2).append(". */\r\n");
			s.append("    public static final String ").append(p.uuname).append(" = \"").append(p.lname).append("\"").append(";\r\n\r\n");
		}
		// Add instance variables.
		for(Iterator i = c.props.iterator(); i.hasNext(); ) {
			Property p = (Property) i.next();
			s.append("    /** ").append(p.desc).append(" */\r\n");
			s.append("    private ").append(p.type).append(" ").append(p.lname).append(";\r\n\r\n");
		}
		// Add getters and setters.
		for(Iterator i = c.props.iterator(); i.hasNext(); ) {
			Property p = (Property) i.next();
			s.append("    /**\r\n");
			s.append("     * Returns ").append(p.desc2).append(".\r\n");
			s.append("     * @return ").append(p.desc2).append("\r\n");
			s.append("     */\r\n");
			s.append("    public ").append(p.type).append(" get").append(p.uname).append("() {\r\n");
			s.append("        return this.").append(p.lname).append(";\r\n");
			s.append("    }\r\n\r\n");
			s.append("    /**\r\n");
			s.append("     * Sets ").append(p.desc2).append(".\r\n");
			s.append("     * @param ").append(p.lname).append(" ").append(p.desc2).append("\r\n");
			s.append("     */\r\n");
			s.append("    public void set").append(p.uname).append("(").append(p.type).append(" ").append(p.lname).append(") {\r\n");
			s.append("        ").append(p.type).append(" oldValue = this.").append(p.lname).append(";\r\n");
			s.append("        this.").append(p.lname).append(" = ").append(p.lname).append(";\r\n");
			s.append("        this.firePropertyChange(").append(p.uuname).append(", oldValue, this.").append(p.lname).append(");\r\n");
			s.append("    }\r\n\r\n");
		}
		// Add the equals() method.
		s.append("    /**\r\n");
		s.append("     * {@inheritDoc}\r\n");
		s.append("     */\r\n");
		s.append("    @Override\r\n");
		s.append("    public boolean equals(Object o) {\r\n");
		s.append("        if (!(o instanceof ").append(c.name).append(")) {\r\n");
		s.append("            return false;\r\n");
		s.append("        }\r\n");
		s.append("        ").append(c.name).append(" other = (").append(c.name).append(") o;\r\n");
		s.append("        return new EqualsBuilder()\r\n");
		for(Iterator i = c.props.iterator(); i.hasNext(); ) {
			Property p = (Property) i.next();
			if(p.biz) {
				s.append("            .append(this.").append(p.lname).append(", other.").append(p.lname).append(")\r\n");
			}
		}
		s.append("            .isEquals();\r\n");
		s.append("    }\r\n\r\n");
		// Add the hashCode() method.
		s.append("    /**\r\n");
		s.append("     * {@inheritDoc}\r\n");
		s.append("     */\r\n");
		s.append("    @Override\r\n");
		s.append("    public int hashCode() {\r\n");
		s.append("        return new HashCodeBuilder()\r\n");
		for(Iterator i = c.props.iterator(); i.hasNext(); ) {
			Property p = (Property) i.next();
			if(p.biz) {
				s.append("            .append(this.").append(p.lname).append(")\r\n");
			}
		}
		s.append("            .toHashCode();\r\n");
		s.append("    }\r\n\r\n");
		// Add the toString() method.
		s.append("    /**\r\n");
		s.append("     * {@inheritDoc}\r\n");
		s.append("     */\r\n");
		s.append("    @Override\r\n");
		s.append("    public String toString() {\r\n");
		s.append("        return createToStringBuilder(this)\r\n");
		for(Iterator i = c.props.iterator(); i.hasNext(); ) {
			Property p = (Property) i.next();
			if(p.biz) {
				s.append("            .append(").append(p.uuname).append(", this.").append(p.lname).append(")\r\n");
			}
		}
		s.append("            .toString();\r\n");
		s.append("    }\r\n\r\n");
		// Close things up.
		s.append("}\r\n");
		return s.toString();
	}

	private static void addHeader(StringBuilder s) {
		s.append("/*\r\n");
		s.append(" * Copyright My Company\r\n");
		s.append(" * \r\n");
		s.append(" * Author : TODO created on ").append(new SimpleDateFormat("MM/dd/yyyy").format(new Date())).append("\r\n");
		s.append(" */\r\n\r\n");
	}

	private static void addPackage(StringBuilder s, String pkg) {
		s.append("package com.mycompany.myproject.").append(pkg).append(".facade.dto;\r\n\r\n");
	}

	private static void addClassJavaDoc(StringBuilder s, String comment) {
		s.append("/**\r\n");
		s.append(" * ").append(comment).append("\r\n");
		s.append(" * \r\n");
		s.append(" * @author TODO (in header, too)\r\n");
		s.append(" */\r\n");
	}

	private Clazz clazz;

	private static class Clazz {
		String pkg;
		String name;
		List props = new ArrayList();
	}

	private static class Property {

		String desc;
		String desc2;
		String lname;
		String uname;
		String uuname;
		String type;
		boolean biz;

		public void setDesc(String s) {
			// Full description with capitalized first letter and a period at the end.
			desc = s;
			desc = desc.substring(3);
			desc = desc.substring(0, desc.length() - 2);
			desc = desc.trim();
			if(!Character.isUpperCase(desc.charAt(0))) {
				desc = desc.substring(0, 1).toUpperCase() + desc.substring(1);
			}
			if(desc.charAt(desc.length() - 1) != '.') {
				desc += ".";
			}
			// Full description without a capitalized first letter and without a period at the end.
			desc2 = desc.substring(0, 1).toLowerCase() + desc.substring(1, desc.length() - 1);
		}

		public void setName(String s) {
			// Create the camel-cased name with an initial lowercase char, the camel-cased name with
			// an initial upper-cased char, and the all-caps name with underscores between words.
			lname = s;
			uname = lname.substring(0, 1).toUpperCase() + lname.substring(1);
			uuname = "PROPERTY_" + makeConstantName(lname);
		}

		private String makeConstantName(String s) {
			// Reference: http://www.palbrattberg.com/2007/06/01/undoing-camelcase/
			Pattern p = Pattern.compile("\\p{Lu}");
			Matcher m = p.matcher(s);
			StringBuffer sb = new StringBuffer();
			while(m.find()) {
				String sub = m.group();
				m.appendReplacement(sb, sub.substring(0, sub.length() - 1) );
				sb.append('_');
				sb.append(sub.substring(sub.length() - 1));
			}
			m.appendTail(sb);
			return sb.toString().toUpperCase();
		}

	}
}

/*-----------------------------------------------------------*/
/*                       Parser Rules                        */
/*-----------------------------------------------------------*/

clazz returns [Clazz c = new Clazz()]
	:	i1=Identifier { c.pkg = $i1.text; } '.' i2=Identifier { c.name = $i2.text; } '{' ( property[c] )* '}'
	;

property[Clazz c]
	:	Comment
		{
			Property p = new Property();
			p.setDesc($Comment.text);
		}
		b='BIZ'?
		{
			p.biz = (b != null);
		}
		type
		{
			p.type = $type.text;
		}
		Identifier
		{
			p.setName($Identifier.text);
		}
		';'
		{
			c.props.add(p);
		}
	;

type	:	Identifier ( '<' Identifier '>' )?
	;

/*-----------------------------------------------------------*/
/*                        Lexer Rules                        */
/*-----------------------------------------------------------*/

Comment
	:	'/*' ( options {greedy=false;} : . )* '*/'
	;

WS
	:	( ' ' | '\t' | '\f' )+ { $channel = HIDDEN; }
	;

EOL
	:	( '\r' | '\n' )+ { $channel = HIDDEN; }
	;

Identifier
	:	AlphaChar AlphaNumericChar*
	;

fragment
AlphaChar
	:	'a'..'z'
	|	'A'..'Z'
	;

fragment
NumericChar
	:	'0'..'9'
	;

fragment
AlphaNumericChar
	:	( AlphaChar | NumericChar)
	;