package org.eclipse.emf.test.tools.merger;

import java.util.Hashtable;

import junit.framework.TestCase;

import org.eclipse.jdt.core.JavaCore;
import org.eclipse.jdt.core.dom.AST;
import org.eclipse.jdt.core.dom.ASTParser;
import org.eclipse.jdt.core.dom.AbstractTypeDeclaration;
import org.eclipse.jdt.core.dom.CompilationUnit;
import org.eclipse.jdt.core.dom.EnumConstantDeclaration;
import org.eclipse.jdt.core.dom.EnumDeclaration;
import org.eclipse.jdt.core.dom.FieldDeclaration;
import org.eclipse.jdt.core.dom.VariableDeclarationFragment;
import org.eclipse.jdt.core.dom.rewrite.ASTRewrite;
import org.eclipse.jdt.core.dom.rewrite.ListRewrite;
import org.eclipse.jface.text.Document;
import org.eclipse.text.edits.TextEdit;

/**
 * Test that shows the difference in assigning line comments in enum and
 * class declarations.
 */
public class ASTEnumProblem extends TestCase
{
  protected String enumSource =
    "enum E\n" +
    "{" +
    "\tENUM_CONST_1(\"String const 1\") //$NON-NLS-1$\n" +
    "\t, ENUM_CONST_2(\"String const 2\") //$NON-NLS-2$\n" +
    "\t;\n" +
    "\tString a; //$NON-NLS-1$\n" +
    "\tString b; //$NON-NLS-2$\n" +
    "}\n";
    
  protected String classSource = 
    "class X\n" +
    "{" +
    "\tString a; //$NON-NLS-1$\n" +
    "\tString b; //$NON-NLS-2$\n" +
    "}\n";
  
  protected String expectedEnumSourceAfterAddingField =
    "enum E\n" +
    "{" +
    "\tENUM_CONST_1(\"String const 1\") //$NON-NLS-1$\n" +
    "\t, ENUM_CONST_2(\"String const 2\") //$NON-NLS-2$\n" +
    "\t;\n" +
    "\tString a; //$NON-NLS-1$\n" +
    "\tString b; //$NON-NLS-2$\n" +    
    "\tint MISSING;\n" +
    "}\n";

  protected String expectedEnumSourceAfterAddingEnumConst =
    "enum E\n" +
    "{" +
    "\tENUM_CONST_1(\"String const 1\") //$NON-NLS-1$\n" +
    "\t, MISSING, ENUM_CONST_2(\"String const 2\") //$NON-NLS-2$\n" +
    "\t, MISSING;\n" +
    "\tString a; //$NON-NLS-1$\n" +
    "\tString b; //$NON-NLS-2$\n" +    
    "}\n";
  
  
  protected String expectedClassSource = 
    "class X\n" +
    "{" +
    "\tString a; //$NON-NLS-1$\n" +
    "\tString b; //$NON-NLS-2$\n" +
    "\tint MISSING;\n" +    
    "}\n";  
  
  protected CompilationUnit enumCompilationUnit;
  protected CompilationUnit classCompilationUnit;
  
  @Override
  protected void setUp() throws Exception
  {
    adjustCompilerOptions();
    enumCompilationUnit = parse(enumSource);
    classCompilationUnit = parse(classSource);    
  }
  
  public void testReadEnumFieldDeclarations()
  {
    testReadFields(enumCompilationUnit, enumSource);
  }

  public void testReadClassFieldDeclarations()
  {
    testReadFields(classCompilationUnit, classSource);
  }
  
  public void testEnumConstants()
  {
    testReadEnumConsts(enumCompilationUnit, enumSource);
  }
  
  public void testAddEnumConst() throws Exception
  {
    assertEquals(expectedEnumSourceAfterAddingEnumConst, testAddConst(enumCompilationUnit, enumSource));
  }  
  
  public void testAddEnumField() throws Exception
  {
    assertEquals(expectedEnumSourceAfterAddingField, testAddField(enumCompilationUnit, enumSource));
  }
  
  public void testAddClassField() throws Exception
  {
    assertEquals(expectedClassSource, testAddField(classCompilationUnit, classSource));
  }    
  
  protected void testReadFields(CompilationUnit cu, String source)
  {
    AbstractTypeDeclaration td = (AbstractTypeDeclaration) cu.types().get(0);

    FieldDeclaration field1 = (FieldDeclaration) td.bodyDeclarations().get(0);
    FieldDeclaration field2 = (FieldDeclaration) td.bodyDeclarations().get(1);    
    
    String field1Source = source.substring(cu.getExtendedStartPosition(field1), cu.getExtendedStartPosition(field1) + cu.getExtendedLength(field1));
    String field2Source = source.substring(cu.getExtendedStartPosition(field2), cu.getExtendedStartPosition(field2) + cu.getExtendedLength(field2));
    
    assertEquals("String a; //$NON-NLS-1$", field1Source);
    // this fails for enum since line comment is not a part of the last field
    assertEquals("String b; //$NON-NLS-2$", field2Source);    
  }
  
  protected void testReadEnumConsts(CompilationUnit cu, String source)
  {
    EnumDeclaration ed = (EnumDeclaration) cu.types().get(0);

    EnumConstantDeclaration constantDeclaration1 = (EnumConstantDeclaration)ed.enumConstants().get(0);
    EnumConstantDeclaration constantDeclaration2 = (EnumConstantDeclaration)ed.enumConstants().get(1);
    
    String const1Source = source.substring(cu.getExtendedStartPosition(constantDeclaration1), cu.getExtendedStartPosition(constantDeclaration1) + cu.getExtendedLength(constantDeclaration1));
    String const2Source = source.substring(cu.getExtendedStartPosition(constantDeclaration2), cu.getExtendedStartPosition(constantDeclaration2) + cu.getExtendedLength(constantDeclaration2));
    
    assertEquals("ENUM_CONST_1(\"String const 1\") //$NON-NLS-1$", const1Source);
    assertEquals("ENUM_CONST_2(\"String const 2\") //$NON-NLS-2$", const2Source);    
  }  
  
  protected String testAddField(CompilationUnit cu, String source) throws Exception
  {
    ASTRewrite rewriter = ASTRewrite.create(cu.getAST());
    
    AbstractTypeDeclaration td = (AbstractTypeDeclaration) cu.types().get(0);
    
    ListRewrite lrw = rewriter.getListRewrite(td, td.getBodyDeclarationsProperty());
    
    VariableDeclarationFragment newFragment = cu.getAST().newVariableDeclarationFragment(); 
    FieldDeclaration newField = cu.getAST().newFieldDeclaration(newFragment);  

    // for enum, new field is inserted before the line comment of the last field    
    lrw.insertLast(newField, null);

    Document doc = new Document(source);    
    TextEdit edit = rewriter.rewriteAST(doc, null);
    edit.apply(doc);
    
    return doc.get();
  }
  
  protected String testAddConst(CompilationUnit cu, String source) throws Exception
  {
    ASTRewrite rewriter = ASTRewrite.create(cu.getAST());
    
    EnumDeclaration ed = (EnumDeclaration) cu.types().get(0);
    
    ListRewrite lrw = rewriter.getListRewrite(ed, EnumDeclaration.ENUM_CONSTANTS_PROPERTY);
    
    EnumConstantDeclaration newEnumConstantDeclaration = cu.getAST().newEnumConstantDeclaration();    
    lrw.insertAt(newEnumConstantDeclaration, 1, null);

    newEnumConstantDeclaration = cu.getAST().newEnumConstantDeclaration();  
    lrw.insertLast(newEnumConstantDeclaration, null);
    
    Document doc = new Document(source);    
    TextEdit edit = rewriter.rewriteAST(doc, null);
    edit.apply(doc);
    
    return doc.get();
  }  
  
  protected CompilationUnit parse(String source)
  {
    ASTParser parser = ASTParser.newParser(AST.JLS3);
    parser.setSource(source.toCharArray());
    return (CompilationUnit) parser.createAST(null);    
  }  
  
  protected void adjustCompilerOptions()
  {
    Hashtable options = JavaCore.getOptions();
    options.put(JavaCore.COMPILER_SOURCE, JavaCore.VERSION_1_5);
    JavaCore.setOptions(options);    
  }  
}