package pablotron.luigi; import java.util.ArrayList; import java.util.regex.Pattern; import java.util.regex.Matcher; import pablotron.luigi.actions.Action; import pablotron.luigi.actions.FilterAction; import pablotron.luigi.actions.TextAction; import pablotron.luigi.FilterReference; import pablotron.luigi.LuigiError; public final class Parser { private static final Pattern RE_ACTION = Pattern.compile( // match opening brace "%\\{" + // match optional whitespace "\\s*" + // match key // "(?[^\\s\\|\\}]+)" + "([^\\s\\|\\}]+)" + // match filter(s) // "(?(\\s*\\|(\\s*[^\\s\\|\\}]+)+)*)" + "((\\s*\\|(\\s*[^\\s\\|\\}]+)+)*)" + // match optional whitespace "\\s*" + // match closing brace "\\}" + // or match up all non-% chars or a single % char // "| (?[^%]* | %)", "| ([^%]* | %)", Pattern.COMMENTS ); private static final Pattern RE_FILTER = Pattern.compile( // match filter name // "(?\\S+)" + "(\\S+)" + // match filter arguments (optional) // "(?(\\s*\\S+)*)" + "((\\s*\\S+)*)" + // optional trailing whitespace "\\s*", Pattern.COMMENTS ); private static final Pattern RE_DELIM_FILTERS = Pattern.compile( "\\s*\\|\\s*" ); private static final Pattern RE_DELIM_ARGS = Pattern.compile( "\\s+" ); public static Action[] parse_template( String template ) throws LuigiError { ArrayList r = new ArrayList(); // match on text final Matcher m = RE_ACTION.matcher(template); while (m.find()) { // String key = m.group("key"); String key = m.group(1); if (key != null && key.length() > 0) { // r.add(new FilterAction(key, parse_filters(m.group("filters")))); r.add(new FilterAction(key, parse_filters(m.group(2)))); } else { // r.add(new TextAction(m.group("text"))); r.add(new TextAction(m.group(5))); } } // build array of results return r.toArray(new Action[r.size()]); } public static FilterReference[] parse_filters( String filters_str ) throws LuigiError { ArrayList r = new ArrayList(); // split string into individual filters and handle each one for (String f: RE_DELIM_FILTERS.split(filters_str)) { // trim filter string and skip empty filters f = f.trim(); if (f.length() == 0) continue; // match on filter and check for error Matcher m = RE_FILTER.matcher(f); if (!m.find()) throw new LuigiError("invalid filter: " + f); // append new filter reference to result r.add(new FilterReference(m.group(1), RE_DELIM_ARGS.split(m.group(2).trim()))); } // return result return r.toArray(new FilterReference[r.size()]); } };