// This Source Code is in the Public Domain per: http://unlicense.org
package org.litesoft.codegen;

import java.util.*;

public class SourceCodeGenerator
{
    public static final SourceCodeGenerator[] EMPTY = new SourceCodeGenerator[0];

    protected static final String JAVA_LANG_PACKAGE = "java.lang.";

    public enum Access
    {
        PUBLIC( "public " ), PROTECTED( "protected " ), PRIVATE( "private " ), PACKAGE( "" );

        Access( String pForm )
        {
            mForm = pForm;
        }

        private String mForm;

        public String getForm()
        {
            return mForm;
        }
    }

    public static final String INDENT = "    ";

    public interface MultiFactory
    {
        public String getName();

        public SourceCodeGenerator[] getSourceCodeGenerators();
    }

    private String mReportingType;
    private String mExternalReference; // eg a File...getPath()
    private Access mClassAccess = Access.PUBLIC;
    private String mClassModifiers = "";
    private String mCurTabDepth = "";
    private StringBuilder mSourceCodeText = new StringBuilder();
    private boolean mOverwrite = true;

    public SourceCodeGenerator( String pReportingType, String pExternalReference )
    {
        mReportingType = pReportingType;
        mExternalReference = pExternalReference;
    }

    public final String getReportingType()
    {
        return mReportingType;
    }

    public final String getExternalReference()
    {
        return mExternalReference;
    }

    public final boolean isOverwrite()
    {
        return mOverwrite;
    }

    public final void setOverwrite( boolean pOverwrite )
    {
        mOverwrite = pOverwrite;
    }

    public final void indentStart()
    {
        mCurTabDepth += INDENT;
    }

    public final void indentEnd()
    {
        if ( mCurTabDepth.startsWith( INDENT ) )
        {
            mCurTabDepth = mCurTabDepth.substring( INDENT.length() );
        }
    }

    public final void indentPlus( int pBy )
    {
        while ( pBy-- > 0 )
        {
            mCurTabDepth += " ";
        }
    }

    public final void indentMinus( int pBy )
    {
        for ( int i = 0; (i < pBy) && mCurTabDepth.startsWith( " " ); i++ )
        {
            mCurTabDepth = mCurTabDepth.substring( 1 );
        }
    }

    public final void indentedAddLine( String pLine )
    {
        indentStart();
        addLine( pLine );
        indentEnd();
    }

    public final void doubleIndentedAddLine( String pLine )
    {
        indentStart();
        indentedAddLine( pLine );
        indentEnd();
    }

    public final void addLineIf( String pLine, boolean pAdd )
    {
        if ( pAdd )
        {
            addLine( pLine );
        }
    }

    public final void addLine( String pLine )
    {
        if ( isNotNullOrEmpty( pLine ) )
        {
            mSourceCodeText.append( mCurTabDepth ).append( pLine );
        }
        mSourceCodeText.append( '\n' );
    }

    public final void addLines( String... pLines )
    {
        if ( pLines != null )
        {
            for ( String line : pLines )
            {
                if ( line != null )
                {
                    addLine( line );
                }
            }
        }
    }

    public final void addLines( List<String> pLines )
    {
        if ( pLines != null )
        {
            for ( String line : pLines )
            {
                if ( line != null )
                {
                    addLine( line );
                }
            }
        }
    }

    public final void addBlankLine()
    {
        mSourceCodeText.append( '\n' );
    }

    public final void addBlockStart()
    {
        addLine( "{" );
        indentStart();
    }

    public final void addBlockStart( String pPlus )
    {
        addLine( "{" + pPlus );
        indentStart();
    }

    public final void addBlockEnd()
    {
        indentEnd();
        addLine( "}" );
    }

    public final void addBlockEnd( String pPlus )
    {
        indentEnd();
        addLine( "}" + pPlus );
    }

    public final void addPackage( String pPackageName )
    {
        if ( isNotNullOrEmpty( pPackageName ) )
        {
            addLine( "package " + pPackageName.trim() + ";" );
            addBlankLine();
        }
    }

    public final void addImports( String... pImportRefs )
    {
        if ( pImportRefs != null )
        {
            for ( String zImportRef : pImportRefs )
            {
                addImport( zImportRef );
            }
            addBlankLine();
        }
    }

    public final void addImport( String pImportRef )
    {
        if ( pImportRef != null )
        {
            if ( pImportRef.length() != 0 )
            {
                addLine( "import " + pImportRef + ";" );
            }
            else
            {
                addBlankLine();
            }
        }
    }

    public final void addInterfaceDefinition( String pInterfaceName, String... pExtendsNames )
    {
        addLine( "public interface " + pInterfaceName );

        String extendsName = csEm( pExtendsNames );

        if ( isNotNullOrEmpty( extendsName ) )
        {
            doubleIndentedAddLine( "extends " + extendsName );
        }
        addBlockStart();
    }

    public final void addInterfaceEnd()
    {
        addBlockEnd();
    }

    public final void makeClassAbstract()
    {
        mClassModifiers += "abstract ";
    }

    public final void makeClassStatic()
    {
        mClassModifiers += "static ";
    }

    public final void makeClassPrivate()
    {
        mClassAccess = Access.PRIVATE;
    }

    public final void makeClassProtected()
    {
        mClassAccess = Access.PROTECTED;
    }

    public final void makeClassPackageFriendly()
    {
        mClassAccess = Access.PACKAGE;
    }

    private Access getClassAccess()
    {
        Access rv = mClassAccess;
        mClassAccess = Access.PUBLIC;
        return rv;
    }

    private String getClassModifiers()
    {
        String rv = mClassModifiers;
        mClassModifiers = "";
        return rv;
    }

    public final void addClassDefinition( String pClassName )
    {
        addClassDefinition( pClassName, null, (String[]) null );
    }

    public final void addClassDefinition( String pClassName, String[] pImplementsNames ) // Note: Can NOT use VarArgs as they would collide with other method!
    {
        addClassDefinition( pClassName, null, pImplementsNames );
    }

    public final void addClassDefinition( String pClassName, String pExtendsName, String... pImplementsNames )
    {
        addLine( getClassAccess().getForm() + getClassModifiers() + "class " + pClassName );

        if ( isNotNullOrEmpty( pExtendsName ) )
        {
            doubleIndentedAddLine( "extends " + pExtendsName.trim() );
        }
        String implementsName = csEm( pImplementsNames );
        if ( isNotNullOrEmpty( implementsName ) )
        {
            doubleIndentedAddLine( "implements " + implementsName.trim() );
        }
        addBlockStart();
    }

    public final void addClassEnd()
    {
        addBlockEnd();
    }

    public final void addPSFS( String pConstantName, String pValue )
    {
        addLine( "public static final String " + pConstantName + " = " + quote( pValue ) + ";" );
    }

    public final String quote( String pValue )
    {
        return (pValue == null) ? "null" : "\"" + pValue + "\"";
    }

    public final void addConstructorPublic( String pClassName, String... pParameters )
    {
        addConstructor( Access.PUBLIC, pClassName, pParameters );
    }

    public final void addConstructorProtected( String pClassName, String... pParameters )
    {
        addConstructor( Access.PROTECTED, pClassName, pParameters );
    }

    public final void addConstructorPrivate( String pClassName, String... pParameters )
    {
        addConstructor( Access.PRIVATE, pClassName, pParameters );
    }

    public final void addConstructorPackageFriendly( String pClassName, String... pParameters )
    {
        addConstructor( Access.PACKAGE, pClassName, pParameters );
    }

    public final void addConstructor( Access pAccess, String pClassName, String... pParameters )
    {
        addLine( pAccess.getForm() + pClassName + parenEm( csEm( pParameters ) ) );
        addBlockStart();
    }

    public final void addMethodPublic( String pReturnType, String pMethodName, String... pParameters )
    {
        addMethod( Access.PUBLIC, pReturnType, pMethodName, pParameters );
    }

    public final void addMethodProtected( String pReturnType, String pMethodName, String... pParameters )
    {
        addMethod( Access.PROTECTED, pReturnType, pMethodName, pParameters );
    }

    public final void addMethodPrivate( String pReturnType, String pMethodName, String... pParameters )
    {
        addMethod( Access.PRIVATE, pReturnType, pMethodName, pParameters );
    }

    public final void addMethodPackageFriendly( String pReturnType, String pMethodName, String... pParameters )
    {
        addMethod( Access.PACKAGE, pReturnType, pMethodName, pParameters );
    }

    public final void addMethod( Access pAccess, String pReturnType, String pMethodName, String... pParameters )
    {
        addLine( pAccess.getForm() + pReturnType + " " + pMethodName + parenEm( csEm( pParameters ) ) );
        addBlockStart();
    }

    public final void addStaticMethodPublic( String pReturnType, String pMethodName, String... pParameters )
    {
        addStaticMethod( Access.PUBLIC, pReturnType, pMethodName, pParameters );
    }

    public final void addStaticMethodProtected( String pReturnType, String pMethodName, String... pParameters )
    {
        addStaticMethod( Access.PROTECTED, pReturnType, pMethodName, pParameters );
    }

    public final void addStaticMethodPrivate( String pReturnType, String pMethodName, String... pParameters )
    {
        addStaticMethod( Access.PRIVATE, pReturnType, pMethodName, pParameters );
    }

    public final void addStaticMethodPackageFriendly( String pReturnType, String pMethodName, String... pParameters )
    {
        addStaticMethod( Access.PACKAGE, pReturnType, pMethodName, pParameters );
    }

    private void addStaticMethod( Access pAccess, String pReturnType, String pMethodName, String... pParameters )
    {
        addLine( pAccess.getForm() + "static " + pReturnType + " " + pMethodName + parenEm( csEm( pParameters ) ) );
        addBlockStart();
    }

    public final void addAbstractMethodPublic( String pReturnType, String pMethodName, String... pParameters )
    {
        addAbstractMethod( Access.PUBLIC, pReturnType, pMethodName, pParameters );
    }

    public final void addAbstractMethodProtected( String pReturnType, String pMethodName, String... pParameters )
    {
        addAbstractMethod( Access.PROTECTED, pReturnType, pMethodName, pParameters );
    }

    private void addAbstractMethod( Access pAccess, String pReturnType, String pMethodName, String... pParameters )
    {
        addLine( "abstract " + pAccess.getForm() + pReturnType + " " + pMethodName + parenEm( csEm( pParameters ) ) + ";" );
    }

    public final void addMethodEnd()
    {
        addBlockEnd();
        addBlankLine();
    }

    public final void addInterfaceMethodDefinition( String pReturnType, String pMethodName, String... pParameters )
    {
        addLine( "public " + pReturnType + " " + pMethodName + parenEm( csEm( pParameters ) ) );
        addBlankLine();
    }

    public final void addTryStart()
    {
        addLine( "try" );
        addBlockStart();
    }

    public final void addTryEnd()
    {
        addBlockEnd();
    }

    public final void addCatch( String pClause )
    {
        addBlockEnd();
        addLine( "catch ( " + pClause + " )" );
        addBlockStart();
    }

    public final void addCatchEnd()
    {
        addBlockEnd();
    }

    private String csEm( String[] pNames )
    {
        if ( (pNames != null) && (pNames.length > 0) )
        {
            StringBuilder sb = new StringBuilder();
            for ( String name : pNames )
            {
                if ( isNotNullOrEmpty( name ) )
                {
                    sb.append( ", " );
                    sb.append( name );
                }
            }
            if ( sb.length() != 0 )
            {
                return sb.toString().substring( 2 );
            }
        }
        return null;
    }

    public final String parenEm( String pParameters )
    {
        return isNotNullOrEmpty( pParameters ) ? "( " + pParameters.trim() + " )" : "()";
    }

    @Override
    public final String toString()
    {
        return mSourceCodeText.toString();
    }

    protected static boolean isNotNullOrEmpty( String pStringToCheck )
    {
        return ((pStringToCheck != null) && (pStringToCheck.trim().length() != 0));
    }
}