package org.litesoft.codegen;

import java.io.*;

import org.litesoft.util.*;

public class AbstractSourceCodeFileGenerator
{
    protected static String mergeFileLines( String... pNewLines )
    {
        int len = 0;
        for ( String pNewLine : pNewLines )
        {
            len += pNewLine.length() + 1;
        }
        StringBuilder sb = new StringBuilder( len );
        for ( String pNewLine : pNewLines )
        {
            sb.append( pNewLine );
            sb.append( '\n' );
        }
        return sb.toString();
    }

    protected static GenerationReport.Action writeChangedFileLines( boolean pWriteIt, File pFile, String... pNewLines )
            throws IOException
    {
        return writeChangedFile( pWriteIt, pFile, pWriteIt ? mergeFileLines( pNewLines ) : "" );
    }

    protected static GenerationReport.Action writeChangedFile( boolean pWriteIt, File pFile, String pNewContents )
            throws IOException
    {
        return writeFile( pWriteIt && (!pFile.exists() || !getFileAsString( pFile ).equals( pNewContents )), pFile, pNewContents );
    }

    protected static GenerationReport.Action writeFile( boolean pWriteIt, File pFile, String pNewContents )
            throws IOException
    {
        if ( !pWriteIt )
        {
            return GenerationReport.Action.NoChange;
        }
        GenerationReport.Action rv;
        if ( pFile.exists() )
        {
            rv = GenerationReport.Action.Updated;
            System.out.println( "Updating: " + pFile );
        }
        else
        {
            rv = GenerationReport.Action.Created;
            System.out.println( "Creating: " + pFile );
            File parentPath = pFile.getParentFile();
            if ( !parentPath.exists() )
            {
                //noinspection ResultOfMethodCallIgnored
                parentPath.mkdirs();
            }
        }
        FileWriter writer = new FileWriter( pFile );
        writer.write( pNewContents );
        writer.close();
        return rv;
    }

    protected static String getFileAsString( File pFile )
            throws IOException
    {
        int bytes = (int) pFile.length();
        StringBuilder sb = new StringBuilder( bytes );

        Reader reader = new BufferedReader( new FileReader( pFile ) );
        for ( int i = 0; i < bytes; i++ )
        {
            sb.append( (char) reader.read() );
        }
        reader.close();

        return sb.toString();
    }

    /**
     * This method returns a string containing zero or more tabs.
     * <p/>
     *
     * @param numTabs Number of tabs to generate
     *
     * @return Description of the Returned Value
     */
    protected static String tabLevel( int numTabs )
    {
        return (numTabs < 1) ? "" : Utils.spaces( numTabs * 4 );
    }

    protected static String deCamelToSpaced( String pName )
    {
        StringBuilder sb = new StringBuilder( pName.length() + 5 );
        for ( int i = 0; i < pName.length(); i++ )
        {
            char c = pName.charAt( i );
            if ( Character.isUpperCase( c ) )
            {
                sb.append( ' ' );
            }
            sb.append( c );
        }
        return sb.toString().trim();
    }

    protected static String deCamelToUnderscoredConstant( String pName )
    {
        StringBuilder sb = new StringBuilder( pName.length() + 5 );
        sb.append( pName.charAt( 0 ) );
        for ( int i = 1; i < pName.length(); i++ )
        {
            char c = pName.charAt( i );
            if ( Character.isUpperCase( c ) )
            {
                sb.append( '_' );
            }
            sb.append( Character.toUpperCase( c ) );
        }
        return sb.toString();
    }
}