debug = System.getenv('DEBUG')

def debug(msg) {

if (debug) System.err.println("[DEBUG] $msg")

}

@Grab('org.apache.velocity:velocity:1.7')

import org.apache.velocity.app.VelocityEngine

templateDirectory = 'templates'

outputDirectory = 'src'

knownFiles = new java.util.HashSet();

def timestamp(dir, file) {

if (file == null) return Long.MAX_VALUE;

file = new java.io.File(dir, file);

knownFiles.add(file);

return file.lastModified();

}

def processTemplate(engine, context, templateFile, outFilename) {

debug("processTemplate('$engine', '$context', '$templateFile', '$outFilename')")

if (outFilename == null) return; // nothing to do

// create output directory if it does not already exist

outFile = new java.io.File(outputDirectory, outFilename);

knownFiles.add(outFile);

if (outFile.getParentFile() != null) outFile.getParentFile().mkdirs();

// apply the template and write out the result

t = engine.getTemplate(templateFile);

writer = new StringWriter();

t.merge(context, writer);

out = new PrintWriter(outFile, "UTF-8");

out.print(writer.toString());

out.close();

}

def parseValue(sh, translationsFile, key, expression) {

try {

result = sh.evaluate(expression)

sh.setVariable(key, result)

return result

}

catch (groovy.lang.GroovyRuntimeException e) {

print("[WARNING] $translationsFile: " +

"key '$key' has unparseable value: " + e.getMessage());

}

}

def readTranslation(engine, globalContext, reader, templateSubdirectory, templateFile, translationsFile, isInclude){

sh = new groovy.lang.GroovyShell();

for (;;) {

// read the line

line = reader.readLine();

if (line == null) break;

// check if the line starts a new section

if (line.startsWith("[") && line.endsWith("]")) {

// if we are parsing a .include file, return when we hit any sections

if(isInclude){

println("[WARNING] $translationsFile: Section definition in .include file. Ending processing of $translationsFile");

return context;

}

// write out the previous file

processTemplate(engine, context, templateFile, outputFilename);

// start a new file

outputFilename = line.substring(1, line.length() - 1);

if (!templateDirectory.equals(templateSubdirectory)) {

subPath = templateSubdirectory.substring(templateDirectory.length() + 1);

outputFilename = "$subPath/$outputFilename";

}

context = new org.apache.velocity.VelocityContext(globalContext);

continue;

}

// ignore blank lines

trimmedLine = line.trim();

if (trimmedLine.isEmpty()) continue;

// ignore comments

if (trimmedLine.startsWith("#")) continue;

// include any global files

if (trimmedLine.startsWith(".include")){

includeFile = line.substring(9);

if(includeFile.startsWith("templates")){

includeSubdirectory = includeFile.substring(0, includeFile.lastIndexOf("/"))

includeFile = includeFile.substring(includeFile.lastIndexOf("/"))

}

else{

includeSubdirectory = templateSubdirectory

}

globalReader = new java.io.BufferedReader(new java.io.FileReader("$includeSubdirectory/$includeFile"));

encapsulatedContext = new org.apache.velocity.VelocityContext(context)

context = readTranslation(engine, encapsulatedContext, globalReader, templateSubdirectory, templateFile, includeFile, true)

continue;

}

if (!line.contains('=')) {

print("[WARNING] $translationsFile: Ignoring spurious line: $line");

continue;

}

int idx = line.indexOf('=');

key = line.substring(0, idx).trim();

value = line.substring(idx + 1);

if (value.trim().equals('```')) {

// multi-line value

builder = new StringBuilder();

for (;;) {

line = reader.readLine();

if (line == null) {

throw new RuntimeException("Unfinished value: " + builder.toString());

}

if (line.equals('```')) {

break;

}

if (builder.length() > 0) {

builder.append("\n");

}

builder.append(line);

}

value = builder.toString();

}

context.put(key, parseValue(sh, translationsFile, key, value));

}

return context;

}

def translate(templateSubdirectory, templateFile, translationsFile) {

debug("translate('$templateSubdirectory', '$templateFile', '$translationsFile')")

// initialize the Velocity engine

engine = new org.apache.velocity.app.VelocityEngine();

p = new java.util.Properties();

// fail if template uses an invalid expression; e.g., an undefined variable

p.setProperty("runtime.references.strict", "true");

// tell Velocity where the templates are located

p.setProperty("file.resource.loader.path", "$templateSubdirectory");

// tell Velocity to log to stderr rather than to a velocity.log file

p.setProperty(org.apache.velocity.runtime.RuntimeConstants.RUNTIME_LOG_LOGSYSTEM_CLASS,

"org.apache.velocity.runtime.log.SystemLogChute");

engine.init(p);

// read translation lines

outputFilename = null;

context = globalContext = new org.apache.velocity.VelocityContext();

reader = new java.io.BufferedReader(new java.io.FileReader("$templateSubdirectory/$translationsFile"));

readTranslation(engine, context, reader, templateSubdirectory, templateFile, translationsFile, false);

reader.close();

// process the template

processTemplate(engine, context, templateFile, outputFilename);

}

def translateDirectory(templateSubdirectory) {

debug("translateDirectory('$templateSubdirectory')")

for (file in new java.io.File(templateSubdirectory).listFiles()) {

if (file.isDirectory()) {

// process subdirectories recursively

translateDirectory(file.getPath());

}

else {

// process Velocity template files only

name = file.getName();

if (!name.endsWith('.vm')) continue;

prefix = name.substring(0, name.lastIndexOf('.'));

translate(templateSubdirectory, name, prefix + '.list');

}

}

}

try {

translateDirectory(templateDirectory);

}

catch (Throwable t) {

t.printStackTrace(System.err);

throw t;

}