/*
 * Copyright 2009 Google Inc.
 * 
 * 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 com.google.gwt.core.ext.linker;

import java.io.Serializable;
import java.util.Comparator;

/**
 * Provides basic information about symbols in the generated JavaScript.
 * 
 * @see CompilationResult#getSymbolMap()
 */
public interface SymbolData extends Serializable {
  /*
   * NB: This class is intended to provide enough data to synthesize
   * StackTraceElements, however we don't want to use STE in our API in the case
   * that we want to provide additional data in the future.
   * 
   * Note also that this class does not provide the name of the symbol it is
   * describing, mainly because the JS compilation process results in multiple
   * symbols that are mapped onto the same SymbolData (e.g. MakeCallsStatic).
   */

  /**
   * A Comparator for use when presenting the data to humans. This Comparator
   * orders SymbolData objects by their class names or JSNI idents.
   */
  class ClassIdentComparator implements Comparator<SymbolData>, Serializable {
    public int compare(SymbolData o1, SymbolData o2) {
      if (o1 == o2) {
        return 0;
      }
      int result = o1.getClassName().compareTo(o2.getClassName());
      if (result != 0) {
        return result;
      }

      // A Class sorts before any member of that class.
      if (o1.isClass()) {
        if (o2.isClass()) {
          return 0;
        } else {
          return -1;
        }
      } else if (o2.isClass()) {
        return 1;
      }

      result = o1.getMemberName().compareTo(o2.getMemberName());
      if (result != 0) {
        return result;
      }

      // A Field sorts before any Method that has the same name.
      if (o1.isField()) {
        if (o2.isField()) {
          return 0;
        } else {
          return -1;
        }
      } else if (o2.isField()) {
        return 1;
      }

      // Must compare jsni signatures to distinguish overloaded methods.
      return o1.getJsniIdent().compareTo(o2.getJsniIdent());
    }
  }
  
  /**
   * Returns a JSON map of castableTypes.
   */
  CastableTypeMap getCastableTypeMap();

  /**
   * Returns the name of the type or enclosing type if the symbol is a method or
   * field.
   */
  String getClassName();

  /**
   * Returns the fragment number in which the symbol is declared (for a method).
   */
  int getFragmentNumber();

  /**
   * Returns a JSNI-like identifier for the symbol if it a method or field,
   * otherwise <code>null</code>.
   */
  String getJsniIdent();

  /**
   * Returns the name of the member if the symbol is a method or field.
   */
  String getMemberName();

  /**
   * Returns the queryId for castability comparisons.
   */
  int getQueryId();

  /**
   * Returns the seedId for types.
   */
  int getSeedId();

  /**
   * Returns the line number on which the symbol was originally declared or
   * <code>-1</code> if the line number is unknown.
   */
  int getSourceLine();

  /**
   * Returns a URI string representing the location of the source. This method
   * will return <code>null</code> if the symbol was derived from a transient
   * or unknown source.
   */
  String getSourceUri();

  /**
   * Returns the JavaScript symbol this data maps to.
   */
  String getSymbolName();

  /**
   * Returns <code>true</code> if the symbol represents a class.
   */
  boolean isClass();

  /**
   * Returns <code>true</code> if the symbol represents a field.
   */
  boolean isField();

  /**
   * Returns <code>true</code> if the symbol represents a method.
   */
  boolean isMethod();
}