--- /dev/null
+/*
+ * Jexer - Java Text User Interface
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (C) 2019 Kevin Lamonte
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ * @author Kevin Lamonte [kevin.lamonte@gmail.com]
+ * @version 1
+ */
+package jexer;
+
+import java.io.IOException;
+
+import jexer.bits.CellAttributes;
+import jexer.event.TKeypressEvent;
+import jexer.event.TMouseEvent;
+import jexer.event.TResizeEvent;
+import jexer.teditor.Document;
+import jexer.teditor.Line;
+import jexer.teditor.Word;
+import static jexer.TKeypress.*;
+
+/**
+ * TEditorWidget displays an editable text document. It is unaware of
+ * scrolling behavior, but can respond to mouse and keyboard events.
+ */
+public class TEditorWidget extends TWidget {
+
+ // ------------------------------------------------------------------------
+ // Constants --------------------------------------------------------------
+ // ------------------------------------------------------------------------
+
+ /**
+ * The number of lines to scroll on mouse wheel up/down.
+ */
+ private static final int wheelScrollSize = 3;
+
+ // ------------------------------------------------------------------------
+ // Variables --------------------------------------------------------------
+ // ------------------------------------------------------------------------
+
+ /**
+ * The document being edited.
+ */
+ private Document document;
+
+ /**
+ * The default color for the TEditor class.
+ */
+ private CellAttributes defaultColor = null;
+
+ /**
+ * The topmost line number in the visible area. 0-based.
+ */
+ private int topLine = 0;
+
+ /**
+ * The leftmost column number in the visible area. 0-based.
+ */
+ private int leftColumn = 0;
+
+ // ------------------------------------------------------------------------
+ // Constructors -----------------------------------------------------------
+ // ------------------------------------------------------------------------
+
+ /**
+ * Public constructor.
+ *
+ * @param parent parent widget
+ * @param text text on the screen
+ * @param x column relative to parent
+ * @param y row relative to parent
+ * @param width width of text area
+ * @param height height of text area
+ */
+ public TEditorWidget(final TWidget parent, final String text, final int x,
+ final int y, final int width, final int height) {
+
+ // Set parent and window
+ super(parent, x, y, width, height);
+
+ setCursorVisible(true);
+
+ defaultColor = getTheme().getColor("teditor");
+ document = new Document(text, defaultColor);
+ }
+
+ // ------------------------------------------------------------------------
+ // TWidget ----------------------------------------------------------------
+ // ------------------------------------------------------------------------
+
+ /**
+ * Draw the text box.
+ */
+ @Override
+ public void draw() {
+ for (int i = 0; i < getHeight(); i++) {
+ // Background line
+ getScreen().hLineXY(0, i, getWidth(), ' ', defaultColor);
+
+ // Now draw document's line
+ if (topLine + i < document.getLineCount()) {
+ Line line = document.getLine(topLine + i);
+ int x = 0;
+ for (Word word: line.getWords()) {
+ // For now, we are cheating: draw outside the left region
+ // if needed and let screen do the clipping.
+ getScreen().putStringXY(x - leftColumn, i, word.getText(),
+ word.getColor());
+ x += word.getDisplayLength();
+ if (x - leftColumn > getWidth()) {
+ break;
+ }
+ }
+ }
+ }
+ }
+
+ /**
+ * Handle mouse press events.
+ *
+ * @param mouse mouse button press event
+ */
+ @Override
+ public void onMouseDown(final TMouseEvent mouse) {
+ if (mouse.isMouseWheelUp()) {
+ for (int i = 0; i < wheelScrollSize; i++) {
+ if (topLine > 0) {
+ topLine--;
+ alignDocument(false);
+ }
+ }
+ return;
+ }
+ if (mouse.isMouseWheelDown()) {
+ for (int i = 0; i < wheelScrollSize; i++) {
+ if (topLine < document.getLineCount() - 1) {
+ topLine++;
+ alignDocument(true);
+ }
+ }
+ return;
+ }
+
+ if (mouse.isMouse1()) {
+ // Set the row and column
+ int newLine = topLine + mouse.getY();
+ int newX = leftColumn + mouse.getX();
+ if (newLine > document.getLineCount() - 1) {
+ // Go to the end
+ document.setLineNumber(document.getLineCount() - 1);
+ document.end();
+ if (newLine > document.getLineCount() - 1) {
+ setCursorY(document.getLineCount() - 1 - topLine);
+ } else {
+ setCursorY(mouse.getY());
+ }
+ alignCursor();
+ return;
+ }
+
+ document.setLineNumber(newLine);
+ setCursorY(mouse.getY());
+ if (newX >= document.getCurrentLine().getDisplayLength()) {
+ document.end();
+ alignCursor();
+ } else {
+ document.setCursor(newX);
+ setCursorX(mouse.getX());
+ }
+ return;
+ }
+
+ // Pass to children
+ super.onMouseDown(mouse);
+ }
+
+ /**
+ * Handle keystrokes.
+ *
+ * @param keypress keystroke event
+ */
+ @Override
+ public void onKeypress(final TKeypressEvent keypress) {
+ if (keypress.equals(kbLeft)) {
+ document.left();
+ alignTopLine(false);
+ } else if (keypress.equals(kbRight)) {
+ document.right();
+ alignTopLine(true);
+ } else if (keypress.equals(kbAltLeft)
+ || keypress.equals(kbCtrlLeft)
+ ) {
+ document.backwardsWord();
+ alignTopLine(false);
+ } else if (keypress.equals(kbAltRight)
+ || keypress.equals(kbCtrlRight)
+ ) {
+ document.forwardsWord();
+ alignTopLine(true);
+ } else if (keypress.equals(kbUp)) {
+ document.up();
+ alignTopLine(false);
+ } else if (keypress.equals(kbDown)) {
+ document.down();
+ alignTopLine(true);
+ } else if (keypress.equals(kbPgUp)) {
+ document.up(getHeight() - 1);
+ alignTopLine(false);
+ } else if (keypress.equals(kbPgDn)) {
+ document.down(getHeight() - 1);
+ alignTopLine(true);
+ } else if (keypress.equals(kbHome)) {
+ if (document.home()) {
+ leftColumn = 0;
+ if (leftColumn < 0) {
+ leftColumn = 0;
+ }
+ setCursorX(0);
+ }
+ } else if (keypress.equals(kbEnd)) {
+ if (document.end()) {
+ alignCursor();
+ }
+ } else if (keypress.equals(kbCtrlHome)) {
+ document.setLineNumber(0);
+ document.home();
+ topLine = 0;
+ leftColumn = 0;
+ setCursorX(0);
+ setCursorY(0);
+ } else if (keypress.equals(kbCtrlEnd)) {
+ document.setLineNumber(document.getLineCount() - 1);
+ document.end();
+ alignTopLine(false);
+ } else if (keypress.equals(kbIns)) {
+ document.setOverwrite(!document.getOverwrite());
+ } else if (keypress.equals(kbDel)) {
+ document.del();
+ alignCursor();
+ } else if (keypress.equals(kbBackspace)
+ || keypress.equals(kbBackspaceDel)
+ ) {
+ document.backspace();
+ alignTopLine(false);
+ } else if (keypress.equals(kbTab)) {
+ // TODO: tab character. For now just add spaces until we hit
+ // modulo 8.
+ for (int i = document.getCursor(); (i + 1) % 8 != 0; i++) {
+ document.addChar(' ');
+ }
+ alignCursor();
+ } else if (keypress.equals(kbEnter)) {
+ document.enter();
+ alignTopLine(true);
+ } else if (!keypress.getKey().isFnKey()
+ && !keypress.getKey().isAlt()
+ && !keypress.getKey().isCtrl()
+ ) {
+ // Plain old keystroke, process it
+ document.addChar(keypress.getKey().getChar());
+ alignCursor();
+ } else {
+ // Pass other keys (tab etc.) on to TWidget
+ super.onKeypress(keypress);
+ }
+ }
+
+ /**
+ * Method that subclasses can override to handle window/screen resize
+ * events.
+ *
+ * @param resize resize event
+ */
+ @Override
+ public void onResize(final TResizeEvent resize) {
+ // Change my width/height, and pull the cursor in as needed.
+ if (resize.getType() == TResizeEvent.Type.WIDGET) {
+ setWidth(resize.getWidth());
+ setHeight(resize.getHeight());
+ // See if the cursor is now outside the window, and if so move
+ // things.
+ if (getCursorX() >= getWidth()) {
+ leftColumn += getCursorX() - (getWidth() - 1);
+ setCursorX(getWidth() - 1);
+ }
+ if (getCursorY() >= getHeight()) {
+ topLine += getCursorY() - (getHeight() - 1);
+ setCursorY(getHeight() - 1);
+ }
+ } else {
+ // Let superclass handle it
+ super.onResize(resize);
+ }
+ }
+
+ // ------------------------------------------------------------------------
+ // TEditorWidget ----------------------------------------------------------
+ // ------------------------------------------------------------------------
+
+ /**
+ * Align visible area with document current line.
+ *
+ * @param topLineIsTop if true, make the top visible line the document
+ * current line if it was off-screen. If false, make the bottom visible
+ * line the document current line.
+ */
+ private void alignTopLine(final boolean topLineIsTop) {
+ int line = document.getLineNumber();
+
+ if ((line < topLine) || (line > topLine + getHeight() - 1)) {
+ // Need to move topLine to bring document back into view.
+ if (topLineIsTop) {
+ topLine = line - (getHeight() - 1);
+ if (topLine < 0) {
+ topLine = 0;
+ }
+ assert (topLine >= 0);
+ } else {
+ topLine = line;
+ assert (topLine >= 0);
+ }
+ }
+
+ /*
+ System.err.println("line " + line + " topLine " + topLine);
+ */
+
+ // Document is in view, let's set cursorY
+ assert (line >= topLine);
+ setCursorY(line - topLine);
+ alignCursor();
+ }
+
+ /**
+ * Align document current line with visible area.
+ *
+ * @param topLineIsTop if true, make the top visible line the document
+ * current line if it was off-screen. If false, make the bottom visible
+ * line the document current line.
+ */
+ private void alignDocument(final boolean topLineIsTop) {
+ int line = document.getLineNumber();
+ int cursor = document.getCursor();
+
+ if ((line < topLine) || (line > topLine + getHeight() - 1)) {
+ // Need to move document to ensure it fits view.
+ if (topLineIsTop) {
+ document.setLineNumber(topLine);
+ } else {
+ document.setLineNumber(topLine + (getHeight() - 1));
+ }
+ if (cursor < document.getCurrentLine().getDisplayLength()) {
+ document.setCursor(cursor);
+ }
+ }
+
+ /*
+ System.err.println("getLineNumber() " + document.getLineNumber() +
+ " topLine " + topLine);
+ */
+
+ // Document is in view, let's set cursorY
+ setCursorY(document.getLineNumber() - topLine);
+ alignCursor();
+ }
+
+ /**
+ * Align visible cursor with document cursor.
+ */
+ private void alignCursor() {
+ int width = getWidth();
+
+ int desiredX = document.getCursor() - leftColumn;
+ if (desiredX < 0) {
+ // We need to push the screen to the left.
+ leftColumn = document.getCursor();
+ } else if (desiredX > width - 1) {
+ // We need to push the screen to the right.
+ leftColumn = document.getCursor() - (width - 1);
+ }
+
+ /*
+ System.err.println("document cursor " + document.getCursor() +
+ " leftColumn " + leftColumn);
+ */
+
+
+ setCursorX(document.getCursor() - leftColumn);
+ }
+
+ /**
+ * Get the number of lines in the underlying Document.
+ *
+ * @return the number of lines
+ */
+ public int getLineCount() {
+ return document.getLineCount();
+ }
+
+ /**
+ * Get the current visible top row number. 1-based.
+ *
+ * @return the visible top row number. Row 1 is the first row.
+ */
+ public int getVisibleRowNumber() {
+ return topLine + 1;
+ }
+
+ /**
+ * Set the current visible row number. 1-based.
+ *
+ * @param row the new visible row number. Row 1 is the first row.
+ */
+ public void setVisibleRowNumber(final int row) {
+ assert (row > 0);
+ if ((row > 0) && (row < document.getLineCount())) {
+ topLine = row - 1;
+ alignDocument(true);
+ }
+ }
+
+ /**
+ * Get the current editing row number. 1-based.
+ *
+ * @return the editing row number. Row 1 is the first row.
+ */
+ public int getEditingRowNumber() {
+ return document.getLineNumber() + 1;
+ }
+
+ /**
+ * Set the current editing row number. 1-based.
+ *
+ * @param row the new editing row number. Row 1 is the first row.
+ */
+ public void setEditingRowNumber(final int row) {
+ assert (row > 0);
+ if ((row > 0) && (row < document.getLineCount())) {
+ document.setLineNumber(row - 1);
+ alignTopLine(true);
+ }
+ }
+
+ /**
+ * Set the current visible column number. 1-based.
+ *
+ * @return the visible column number. Column 1 is the first column.
+ */
+ public int getVisibleColumnNumber() {
+ return leftColumn + 1;
+ }
+
+ /**
+ * Set the current visible column number. 1-based.
+ *
+ * @param column the new visible column number. Column 1 is the first
+ * column.
+ */
+ public void setVisibleColumnNumber(final int column) {
+ assert (column > 0);
+ if ((column > 0) && (column < document.getLineLengthMax())) {
+ leftColumn = column - 1;
+ alignDocument(true);
+ }
+ }
+
+ /**
+ * Get the current editing column number. 1-based.
+ *
+ * @return the editing column number. Column 1 is the first column.
+ */
+ public int getEditingColumnNumber() {
+ return document.getCursor() + 1;
+ }
+
+ /**
+ * Set the current editing column number. 1-based.
+ *
+ * @param column the new editing column number. Column 1 is the first
+ * column.
+ */
+ public void setEditingColumnNumber(final int column) {
+ if ((column > 0) && (column < document.getLineLength())) {
+ document.setCursor(column - 1);
+ alignCursor();
+ }
+ }
+
+ /**
+ * Get the maximum possible row number. 1-based.
+ *
+ * @return the maximum row number. Row 1 is the first row.
+ */
+ public int getMaximumRowNumber() {
+ return document.getLineCount() + 1;
+ }
+
+ /**
+ * Get the maximum possible column number. 1-based.
+ *
+ * @return the maximum column number. Column 1 is the first column.
+ */
+ public int getMaximumColumnNumber() {
+ return document.getLineLengthMax() + 1;
+ }
+
+ /**
+ * Get the dirty value.
+ *
+ * @return true if the buffer is dirty
+ */
+ public boolean isDirty() {
+ return document.isDirty();
+ }
+
+ /**
+ * Save contents to file.
+ *
+ * @param filename file to save to
+ * @throws IOException if a java.io operation throws
+ */
+ public void saveToFilename(final String filename) throws IOException {
+ document.saveToFilename(filename);
+ }
+
+}