package pyUML.refactoring;

import java.io.File;


import pyUML.backend.ParseHelpers;
import pyUML.pythonTree.PythonTreeFile;

/**
 * Some convenience methods for modifying/writing files  
 */
public class FileRefactoring {
	
	
	/**
	 * replaces a string in a file from a given line/col
	 * deletes the file from that position unto 
	 *
	 * @param pyFile the python file to edit
	 * @param startLine the line, from which the replace should begin
	 * @param startCol the column, from which the replace should begin
	 * @param newString the new String to replace the deleted with
	 * @param endMarker the char/string, unto the file content is replaces
	 * @param reInit if true, a reInit() is called on the python file after finishing
	 * @return
	 */
	public static boolean replaceFromCoordinate(PythonTreeFile pyFile, int startLine, int startCol, String newString, String endMarker, boolean reInit){
		String content = pyFile.getFileContent();
		int lineIndex = 0;
		for (int i=1; i<startLine; i++) {
			lineIndex = content.indexOf('\n' ,lineIndex)+1;			
		}
		int startIndex = lineIndex + startCol -1;
		int endIndex = content.indexOf(endMarker, startIndex);
		String newContent = content.substring(0, startIndex) + newString + content.substring(endIndex);
		ParseHelpers.stringToFile(new File(pyFile.getFilePath().toOSString()), newContent, pyFile.getProject());
		pyFile.setFileContent(newContent);
		return true;
	}
	
	/**
	 * inserts the given string at the beginning of the given line
	 * 
	 * @param pyFile
	 * @param insertLine
	 * @param newString
	 * @return success
	 */
	public static boolean insertAtLine(PythonTreeFile pyFile, int insertLine, String newString){
		String content = pyFile.getFileContent();
		int lineIndex = 0;
		for (int i=1; i<insertLine; i++) {
			lineIndex = content.indexOf('\n' ,lineIndex)+1;			
		}
		String newContent = content.substring(0, lineIndex) + newString + content.substring(lineIndex);
		ParseHelpers.stringToFile(new File(pyFile.getFilePath().toOSString()), newContent, pyFile.getProject());
		pyFile.setFileContent(newContent);
		return true;
	}
	
	/**
	 * completely replace a given line in a python file
	 * @param pyFile
	 * @param lineNo
	 * @param newString
	 * @param writeToFile if true, the changes are directly written to the python file
	 * @return the String with the replaced line
	 */
	public static String replaceLine(PythonTreeFile pyFile, int lineNo, String newString, boolean writeToFile) {
		String content = pyFile.getFileContent();
		int lineIndex = 0;
		for (int i=1; i<lineNo; i++) {
			lineIndex = content.indexOf('\n' ,lineIndex)+1;			
		}
		int lineIndexAfter = content.indexOf('\n' ,lineIndex);
		
		String contentBefore = content.substring(0, lineIndex);
		String newContent = contentBefore + newString;
		if (lineIndexAfter > lineIndex) {
			String contentAfter =  content.substring(lineIndexAfter);
			newContent += contentAfter;
		}
		if (writeToFile) {
			ParseHelpers.stringToFile(new File(pyFile.getFilePath().toOSString()), newContent, pyFile.getProject());
			pyFile.updateFileInEclipse();
		}
		pyFile.setFileContent(newContent);
		
		return newContent;
	}
	
	/**
	 * completely removes a given line in a python file
	 * @param pyFile
	 * @param lineNo The lineNo to deletes
	 * @param writeToFile if true, the changes are directly written to the python file
	 * @param onlyIfNotEmpty if true, only a non-empty-line is deleted (to preserve file design)
	 * @return the String with the replaced line
	 */
	public static String removeLine(PythonTreeFile pyFile, int lineNo, boolean writeToFile, boolean onlyIfNotEmpty) {
		String content = pyFile.getFileContent();
		int lineIndex = 0;
		for (int i=1; i<lineNo+1; i++) {
			lineIndex = content.indexOf('\n' ,lineIndex)+1;			
		}
		int lineIndexAfter = content.indexOf('\n' ,lineIndex)+1;
		
		String contentBefore = content.substring(0, lineIndex);
		String newContent = contentBefore;
		if (lineIndexAfter > lineIndex) {
			String contentAfter =  content.substring(lineIndexAfter);
			newContent += contentAfter;
		}
		if (onlyIfNotEmpty) {
			String lineToDelete = content.substring(lineIndex+1, lineIndexAfter );
			if (lineToDelete.matches("[\\s]*"))
				return content;
		}
		
		if (writeToFile) {
			ParseHelpers.stringToFile(new File(pyFile.getFilePath().toOSString()), newContent, pyFile.getProject());
			pyFile.updateFileInEclipse();
		}
		
		pyFile.setFileContent(newContent);
		return newContent;
	}

	/**
	 * Appends a String to a PythonTreeFile and saves the file on disk
	 * @param pyFile
	 * @param stringToAppend
	 * @return
	 */
	public static boolean appendToFile(PythonTreeFile pyFile, String stringToAppend) {
		String content = pyFile.getFileContent();
		String newContent = content + stringToAppend;
		ParseHelpers.stringToFile(new File(pyFile.getFilePath().toOSString()), newContent, pyFile.getProject());
		pyFile.updateFileInEclipse();
		pyFile.setFileContent(newContent);
		return true;
	}
	
	/**
	 * Returns the line with the given line number
	 * for this file. Line numbers start with 1, not with 0
	 * @param pyFile the PythonTreeFile which represents the file
	 * @param lineNo the lineNumber
	 * @return The searched line as a string, null if lineNo is
	 *         not in index.
	 */
	public static String getLine(PythonTreeFile pyFile, int lineNo) {
		String[] splittedFileContent = pyFile.getSplittedFileContent();
		if (lineNo <= 0)
			return null;
		if (lineNo > splittedFileContent.length)
			return null;
		
		return splittedFileContent[lineNo - 1];
	}
}