*
* The MIT License (MIT)
*
- * Copyright (C) 2017 Kevin Lamonte
+ * 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"),
import java.util.ArrayList;
import java.util.List;
+import jexer.bits.CellAttributes;
+import jexer.bits.GraphicsChars;
+import jexer.bits.StringUtils;
+
/**
* A Line represents a single line of text on the screen, as a collection of
* words.
*/
public class Line {
+ // ------------------------------------------------------------------------
+ // Variables --------------------------------------------------------------
+ // ------------------------------------------------------------------------
+
/**
* The list of words.
*/
private ArrayList<Word> words = new ArrayList<Word>();
/**
- * The current cursor position on this line.
+ * The default color for the TEditor class.
+ */
+ private CellAttributes defaultColor = null;
+
+ /**
+ * The text highlighter to use.
+ */
+ private Highlighter highlighter = null;
+
+ /**
+ * The current edition position on this line.
+ */
+ private int position = 0;
+
+ /**
+ * The current editing position screen column number.
+ */
+ private int screenPosition = 0;
+
+ /**
+ * The raw text of this line, what is passed to Word to determine
+ * highlighting behavior.
+ */
+ private StringBuilder rawText;
+
+ // ------------------------------------------------------------------------
+ // Constructors -----------------------------------------------------------
+ // ------------------------------------------------------------------------
+
+ /**
+ * Construct a new Line from an existing text string, and highlight
+ * certain strings.
+ *
+ * @param str the text string
+ * @param defaultColor the color for unhighlighted text
+ * @param highlighter the highlighter to use
+ */
+ public Line(final String str, final CellAttributes defaultColor,
+ final Highlighter highlighter) {
+
+ this.defaultColor = defaultColor;
+ this.highlighter = highlighter;
+
+ this.rawText = new StringBuilder();
+ int col = 0;
+ for (int i = 0; i < str.length(); i++) {
+ char ch = str.charAt(i);
+ if (ch == '\t') {
+ // Expand tabs
+ int j = col % 8;
+ do {
+ rawText.append(' ');
+ j++;
+ col++;
+ } while ((j % 8) != 0);
+ continue;
+ }
+ if ((ch <= 0x20) || (ch == 0x7F)) {
+ // Replace all other C0 bytes with CP437 glyphs.
+ rawText.append(GraphicsChars.CP437[(int) ch]);
+ col++;
+ continue;
+ }
+
+ rawText.append(ch);
+ col++;
+ }
+
+ scanLine();
+ }
+
+ /**
+ * Construct a new Line from an existing text string.
+ *
+ * @param str the text string
+ * @param defaultColor the color for unhighlighted text
*/
- private int cursorX;
+ public Line(final String str, final CellAttributes defaultColor) {
+ this(str, defaultColor, null);
+ }
/**
- * The current word that the cursor position is in.
+ * Private constructor used by dup().
*/
- private Word currentWord;
+ private Line() {
+ // NOP
+ }
+
+ // ------------------------------------------------------------------------
+ // Line -------------------------------------------------------------------
+ // ------------------------------------------------------------------------
/**
- * We use getDisplayLength() a lot, so cache the value.
+ * Create a duplicate instance.
+ *
+ * @return duplicate intance
*/
- private int displayLength = -1;
+ public Line dup() {
+ Line other = new Line();
+ other.defaultColor = defaultColor;
+ other.highlighter = highlighter;
+ other.position = position;
+ other.screenPosition = screenPosition;
+ other.rawText = new StringBuilder(rawText);
+ other.scanLine();
+ return other;
+ }
/**
- * Get a (shallow) copy of the list of words.
+ * Get a (shallow) copy of the words in this line.
*
- * @return the list of words
+ * @return a copy of the word list
*/
public List<Word> getWords() {
return new ArrayList<Word>(words);
}
+ /**
+ * Get the current cursor position in the text.
+ *
+ * @return the cursor position
+ */
+ public int getRawCursor() {
+ return position;
+ }
+
+ /**
+ * Get the current cursor position on screen.
+ *
+ * @return the cursor position
+ */
+ public int getCursor() {
+ return screenPosition;
+ }
+
+ /**
+ * Set the current cursor position.
+ *
+ * @param cursor the new cursor position
+ */
+ public void setCursor(final int cursor) {
+ if ((cursor < 0)
+ || ((cursor >= getDisplayLength())
+ && (getDisplayLength() > 0))
+ ) {
+ throw new IndexOutOfBoundsException("Max length is " +
+ getDisplayLength() + ", requested position " + cursor);
+ }
+ screenPosition = cursor;
+ position = screenToTextPosition(screenPosition);
+ }
+
+ /**
+ * Get the character at the current cursor position in the text.
+ *
+ * @return the character, or -1 if the cursor is at the end of the line
+ */
+ public int getChar() {
+ if (position == rawText.length()) {
+ return -1;
+ }
+ return rawText.codePointAt(position);
+ }
+
/**
* Get the on-screen display length.
*
* @return the number of cells needed to display this line
*/
public int getDisplayLength() {
- if (displayLength != -1) {
- return displayLength;
- }
- int n = 0;
- for (Word word: words) {
- n += word.getDisplayLength();
+ int n = StringUtils.width(rawText.toString());
+
+ if (n > 0) {
+ // If we have any visible characters, add one to the display so
+ // that the position is immediately after the data.
+ return n + 1;
}
- displayLength = n;
- return displayLength;
+ return n;
}
/**
- * Construct a new Line from an existing text string.
+ * Get the raw string that matches this line.
*
- * @param str the text string
+ * @return the string
*/
- public Line(final String str) {
- currentWord = new Word();
- words.add(currentWord);
- for (int i = 0; i < str.length(); i++) {
- char ch = str.charAt(i);
- Word newWord = currentWord.addChar(ch);
- if (newWord != currentWord) {
+ public String getRawString() {
+ return rawText.toString();
+ }
+
+ /**
+ * Get the raw length of this line.
+ *
+ * @return the length of this line in characters, which may be different
+ * from the number of cells needed to display it
+ */
+ public int length() {
+ return rawText.length();
+ }
+
+ /**
+ * Scan rawText and make words out of it. Note package private access.
+ */
+ void scanLine() {
+ words.clear();
+ Word word = new Word(this.defaultColor, this.highlighter);
+ words.add(word);
+ for (int i = 0; i < rawText.length();) {
+ int ch = rawText.codePointAt(i);
+ i += Character.charCount(ch);
+ Word newWord = word.addChar(ch);
+ if (newWord != word) {
words.add(newWord);
- currentWord = newWord;
+ word = newWord;
}
}
+ for (Word w: words) {
+ w.applyHighlight();
+ }
}
/**
* Decrement the cursor by one. If at the first column, do nothing.
+ *
+ * @return true if the cursor position changed
*/
- public void left() {
- if (cursorX == 0) {
- return;
+ public boolean left() {
+ if (position == 0) {
+ return false;
}
- // TODO
+ screenPosition -= StringUtils.width(rawText.codePointBefore(position));
+ position -= Character.charCount(rawText.codePointBefore(position));
+ return true;
}
/**
* Increment the cursor by one. If at the last column, do nothing.
+ *
+ * @return true if the cursor position changed
*/
- public void right() {
- if (cursorX == getDisplayLength() - 1) {
- return;
+ public boolean right() {
+ if (getDisplayLength() == 0) {
+ return false;
}
- // TODO
+ if (screenPosition == getDisplayLength() - 1) {
+ return false;
+ }
+ if (position < rawText.length()) {
+ screenPosition += StringUtils.width(rawText.codePointAt(position));
+ position += Character.charCount(rawText.codePointAt(position));
+ }
+ assert (position <= rawText.length());
+ return true;
}
/**
* Go to the first column of this line.
+ *
+ * @return true if the cursor position changed
*/
- public void home() {
- // TODO
+ public boolean home() {
+ if (position > 0) {
+ position = 0;
+ screenPosition = 0;
+ return true;
+ }
+ return false;
}
/**
* Go to the last column of this line.
+ *
+ * @return true if the cursor position changed
*/
- public void end() {
- // TODO
+ public boolean end() {
+ if (screenPosition != getDisplayLength() - 1) {
+ position = rawText.length();
+ screenPosition = StringUtils.width(rawText.toString());
+ return true;
+ }
+ return false;
}
/**
* Delete the character under the cursor.
*/
public void del() {
- // TODO
+ assert (words.size() > 0);
+
+ if (screenPosition < getDisplayLength()) {
+ int n = Character.charCount(rawText.codePointAt(position));
+ for (int i = 0; i < n; i++) {
+ rawText.deleteCharAt(position);
+ }
+ }
+
+ // Re-scan the line to determine the new word boundaries.
+ scanLine();
}
/**
* Delete the character immediately preceeding the cursor.
+ *
+ * @param tabSize the tab stop size
+ * @param backspaceUnindents If true, backspace at an indent level goes
+ * back a full indent level. If false, backspace always goes back one
+ * column.
*/
- public void backspace() {
- // TODO
+ public void backspace(final int tabSize, final boolean backspaceUnindents) {
+ if ((backspaceUnindents == true)
+ && (tabSize > 0)
+ && (screenPosition > 0)
+ && (rawText.charAt(position - 1) == ' ')
+ && ((screenPosition % tabSize) == 0)
+ ) {
+ boolean doBackTab = true;
+ for (int i = 0; i < position; i++) {
+ if (rawText.charAt(i) != ' ') {
+ doBackTab = false;
+ break;
+ }
+ }
+ if (doBackTab) {
+ backTab(tabSize);
+ return;
+ }
+ }
+
+ if (left()) {
+ del();
+ }
}
/**
- * Replace or insert a character at the cursor, depending on overwrite
- * flag.
+ * Insert a character at the cursor.
*
- * @param ch the character to replace or insert
+ * @param ch the character to insert
*/
- public void addChar(final char ch) {
- // TODO
+ public void addChar(final int ch) {
+ if (screenPosition < getDisplayLength() - 1) {
+ rawText.insert(position, Character.toChars(ch));
+ } else {
+ rawText.append(Character.toChars(ch));
+ }
+ position += Character.charCount(ch);
+ screenPosition += StringUtils.width(ch);
+ scanLine();
+ }
+
+ /**
+ * Replace a character at the cursor.
+ *
+ * @param ch the character to replace
+ */
+ public void replaceChar(final int ch) {
+ if (screenPosition < getDisplayLength() - 1) {
+ // Replace character
+ String oldText = rawText.toString();
+ rawText = new StringBuilder(oldText.substring(0, position));
+ rawText.append(Character.toChars(ch));
+ rawText.append(oldText.substring(position + 1));
+ screenPosition += StringUtils.width(rawText.codePointAt(position));
+ position += Character.charCount(ch);
+ } else {
+ rawText.append(Character.toChars(ch));
+ position += Character.charCount(ch);
+ screenPosition += StringUtils.width(ch);
+ }
+ scanLine();
+ }
+
+ /**
+ * Determine string position from screen position.
+ *
+ * @param screenPosition the position on screen
+ * @return the equivalent position in text
+ */
+ private int screenToTextPosition(final int screenPosition) {
+ if (screenPosition == 0) {
+ return 0;
+ }
+
+ int n = 0;
+ for (int i = 0; i < rawText.length(); i++) {
+ n += StringUtils.width(rawText.codePointAt(i));
+ if (n >= screenPosition) {
+ return i + 1;
+ }
+ }
+ // screenPosition exceeds the available text length.
+ throw new IndexOutOfBoundsException("screenPosition " + screenPosition +
+ " exceeds available text length " + rawText.length());
+ }
+
+ /**
+ * Trim trailing whitespace from line, repositioning cursor if needed.
+ */
+ public void trimRight() {
+ if (rawText.length() == 0) {
+ return;
+ }
+ if (!Character.isWhitespace(rawText.charAt(rawText.length() - 1))) {
+ return;
+ }
+ while ((rawText.length() > 0)
+ && Character.isWhitespace(rawText.charAt(rawText.length() - 1))
+ ) {
+ rawText.deleteCharAt(rawText.length() - 1);
+ }
+ if (position >= rawText.length()) {
+ end();
+ }
+ scanLine();
+ }
+
+ /**
+ * Handle the tab character.
+ *
+ * @param tabSize the tab stop size
+ */
+ public void tab(final int tabSize) {
+ if (tabSize > 0) {
+ do {
+ addChar(' ');
+ } while ((screenPosition % tabSize) != 0);
+ }
+ }
+
+ /**
+ * Handle the backtab (shift-tab) character.
+ *
+ * @param tabSize the tab stop size
+ */
+ public void backTab(final int tabSize) {
+ if ((tabSize > 0) && (screenPosition > 0)
+ && (rawText.charAt(position - 1) == ' ')
+ ) {
+ do {
+ backspace(tabSize, false);
+ } while (((screenPosition % tabSize) != 0)
+ && (screenPosition > 0)
+ && (rawText.charAt(position - 1) == ' '));
+ }
}
}