*
* 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.Cell;
import jexer.bits.CellAttributes;
+import jexer.bits.GraphicsChars;
+import jexer.bits.StringUtils;
/**
- * A Line represents a single line of text on the screen. Each character is
- * a Cell, so it can have color attributes in addition to the basic char.
+ * A Line represents a single line of text on the screen, as a collection of
+ * words.
*/
-public class Line implements Fragment {
+public class Line {
- /**
- * The cells of the line.
- */
- private List<Cell> cells;
+ // ------------------------------------------------------------------------
+ // Variables --------------------------------------------------------------
+ // ------------------------------------------------------------------------
/**
- * The line number.
+ * The list of words.
*/
- private int lineNumber;
+ private ArrayList<Word> words = new ArrayList<Word>();
/**
- * The previous Fragment in the list.
+ * The default color for the TEditor class.
*/
- private Fragment prevFrag;
+ private CellAttributes defaultColor = null;
/**
- * The next Fragment in the list.
+ * The text highlighter to use.
*/
- private Fragment nextFrag;
+ private Highlighter highlighter = null;
/**
- * Construct a new Line from an existing text string.
+ * The current edition position on this line.
*/
- public Line() {
- this("");
- }
+ private int position = 0;
/**
- * Construct a new Line from an existing text string.
- *
- * @param text the code points of the line
+ * The current editing position screen column number.
*/
- public Line(final String text) {
- cells = new ArrayList<Cell>(text.length());
- for (int i = 0; i < text.length(); i++) {
- cells.add(new Cell(text.charAt(i)));
- }
- }
+ private int screenPosition = 0;
/**
- * Reset all colors of this Line to white-on-black.
+ * The raw text of this line, what is passed to Word to determine
+ * highlighting behavior.
*/
- public void resetColors() {
- setColors(new CellAttributes());
- }
+ private StringBuilder rawText;
- /**
- * Set all colors of this Line to one color.
- *
- * @param color the new color to use
- */
- public void setColors(final CellAttributes color) {
- for (Cell cell: cells) {
- cell.setTo(color);
- }
- }
+ // ------------------------------------------------------------------------
+ // Constructors -----------------------------------------------------------
+ // ------------------------------------------------------------------------
/**
- * Set the color of one cell.
+ * Construct a new Line from an existing text string, and highlight
+ * certain strings.
*
- * @param index a cell number, between 0 and getCellCount()
- * @param color the new color to use
- * @throws IndexOutOfBoundsException if index is negative or not less
- * than getCellCount()
+ * @param str the text string
+ * @param defaultColor the color for unhighlighted text
+ * @param highlighter the highlighter to use
*/
- public void setColor(final int index, final CellAttributes color) {
- cells.get(index).setTo(color);
- }
+ public Line(final String str, final CellAttributes defaultColor,
+ final Highlighter highlighter) {
- /**
- * Get the raw text that will be rendered.
- *
- * @return the text
- */
- public String getText() {
- char [] text = new char[cells.size()];
- for (int i = 0; i < cells.size(); i++) {
- text[i] = cells.get(i).getChar();
+ 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++;
}
- return new String(text);
- }
- /**
- * Get the attributes for a cell.
- *
- * @param index a cell number, between 0 and getCellCount()
- * @return the attributes
- * @throws IndexOutOfBoundsException if index is negative or not less
- * than getCellCount()
- */
- public CellAttributes getColor(final int index) {
- return cells.get(index);
+ scanLine();
}
/**
- * Get the number of graphical cells represented by this text. Note that
- * a Unicode grapheme cluster can take any number of pixels, but this
- * editor is intended to be used with a fixed-width font. So this count
- * returns the number of fixed-width cells, NOT the number of grapheme
- * clusters.
+ * Construct a new Line from an existing text string.
*
- * @return the number of fixed-width cells this fragment's text will
- * render to
+ * @param str the text string
+ * @param defaultColor the color for unhighlighted text
*/
- public int getCellCount() {
- return cells.size();
+ public Line(final String str, final CellAttributes defaultColor) {
+ this(str, defaultColor, null);
}
/**
- * Get the text to render for a specific fixed-width cell.
- *
- * @param index a cell number, between 0 and getCellCount()
- * @return the codepoints to render for this fixed-width cell
- * @throws IndexOutOfBoundsException if index is negative or not less
- * than getCellCount()
+ * Private constructor used by dup().
*/
- public Cell getCell(final int index) {
- return cells.get(index);
+ private Line() {
+ // NOP
}
- /**
- * Get the text to render for several fixed-width cells.
- *
- * @param start a cell number, between 0 and getCellCount()
- * @param length the number of cells to return
- * @return the codepoints to render for this fixed-width cell
- * @throws IndexOutOfBoundsException if start or (start + length) is
- * negative or not less than getCellCount()
- */
- public String getCells(final int start, final int length) {
- char [] text = new char[length];
- for (int i = 0; i < length; i++) {
- text[i] = cells.get(i + start).getChar();
- }
- return new String(text);
- }
+ // ------------------------------------------------------------------------
+ // Line -------------------------------------------------------------------
+ // ------------------------------------------------------------------------
/**
- * Sets (replaces) the text to render for a specific fixed-width cell.
+ * Create a duplicate instance.
*
- * @param index a cell number, between 0 and getCellCount()
- * @param ch the character for this fixed-width cell
- * @throws IndexOutOfBoundsException if index is negative or not less
- * than getCellCount()
+ * @return duplicate intance
*/
- public void setCell(final int index, final char ch) {
- cells.set(index, new Cell(ch));
+ 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;
}
/**
- * Sets (replaces) the text to render for a specific fixed-width cell.
+ * Get a (shallow) copy of the words in this line.
*
- * @param index a cell number, between 0 and getCellCount()
- * @param cell the new value for this fixed-width cell
- * @throws IndexOutOfBoundsException if index is negative or not less
- * than getCellCount()
+ * @return a copy of the word list
*/
- public void setCell(final int index, final Cell cell) {
- cells.set(index, cell);
+ public List<Word> getWords() {
+ return new ArrayList<Word>(words);
}
/**
- * Inserts a char to render for a specific fixed-width cell.
+ * Get the current cursor position in the text.
*
- * @param index a cell number, between 0 and getCellCount() - 1
- * @param ch the character for this fixed-width cell
- * @throws IndexOutOfBoundsException if index is negative or not less
- * than getCellCount()
+ * @return the cursor position
*/
- public void insertCell(final int index, final char ch) {
- cells.add(index, new Cell(ch));
+ public int getRawCursor() {
+ return position;
}
/**
- * Inserts a Cell to render for a specific fixed-width cell.
+ * Get the current cursor position on screen.
*
- * @param index a cell number, between 0 and getCellCount() - 1
- * @param cell the new value for this fixed-width cell
- * @throws IndexOutOfBoundsException if index is negative or not less
- * than getCellCount()
+ * @return the cursor position
*/
- public void insertCell(final int index, final Cell cell) {
- cells.add(index, cell);
+ public int getCursor() {
+ return screenPosition;
}
/**
- * Delete a specific fixed-width cell.
+ * Set the current cursor position.
*
- * @param index a cell number, between 0 and getCellCount() - 1
- * @throws IndexOutOfBoundsException if index is negative or not less
- * than getCellCount()
+ * @param cursor the new cursor position
*/
- public void deleteCell(final int index) {
- cells.remove(index);
+ 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);
}
/**
- * Delete several fixed-width cells.
+ * Get the character at the current cursor position in the text.
*
- * @param start a cell number, between 0 and getCellCount() - 1
- * @param length the number of cells to delete
- * @throws IndexOutOfBoundsException if index is negative or not less
- * than getCellCount()
+ * @return the character, or -1 if the cursor is at the end of the line
*/
- public void deleteCells(final int start, final int length) {
- for (int i = 0; i < length; i++) {
- cells.remove(start);
+ public int getChar() {
+ if (position == rawText.length()) {
+ return -1;
}
+ return rawText.codePointAt(position);
}
/**
- * Appends a char to render for a specific fixed-width cell.
+ * Get the on-screen display length.
*
- * @param ch the character for this fixed-width cell
+ * @return the number of cells needed to display this line
*/
- public void appendCell(final char ch) {
- cells.add(new Cell(ch));
+ public int 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;
+ }
+ return n;
}
/**
- * Inserts a Cell to render for a specific fixed-width cell.
+ * Get the raw string that matches this line.
*
- * @param cell the new value for this fixed-width cell
+ * @return the string
*/
- public void appendCell(final Cell cell) {
- cells.add(cell);
+ public String getRawString() {
+ return rawText.toString();
}
/**
- * Get the next Fragment in the list, or null if this Fragment is the
- * last node.
+ * Get the raw length of this line.
*
- * @return the next Fragment, or null
+ * @return the length of this line in characters, which may be different
+ * from the number of cells needed to display it
*/
- public Fragment next() {
- return nextFrag;
+ public int length() {
+ return rawText.length();
}
/**
- * Get the previous Fragment in the list, or null if this Fragment is the
- * first node.
- *
- * @return the previous Fragment, or null
+ * Scan rawText and make words out of it. Note package private access.
*/
- public Fragment prev() {
- return prevFrag;
+ 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);
+ word = newWord;
+ }
+ }
+ for (Word w: words) {
+ w.applyHighlight();
+ }
}
/**
- * See if this Fragment can be joined with the next Fragment in list.
+ * Decrement the cursor by one. If at the first column, do nothing.
*
- * @return true if the join was possible, false otherwise
+ * @return true if the cursor position changed
*/
- public boolean isNextJoinable() {
- if ((nextFrag != null) && (nextFrag instanceof Line)) {
- return true;
+ public boolean left() {
+ if (position == 0) {
+ return false;
}
- return false;
+ screenPosition -= StringUtils.width(rawText.codePointBefore(position));
+ position -= Character.charCount(rawText.codePointBefore(position));
+ return true;
}
/**
- * Join this Fragment with the next Fragment in list.
+ * Increment the cursor by one. If at the last column, do nothing.
*
- * @return true if the join was successful, false otherwise
+ * @return true if the cursor position changed
*/
- public boolean joinNext() {
- if ((nextFrag == null) || !(nextFrag instanceof Line)) {
+ public boolean right() {
+ if (getDisplayLength() == 0) {
+ return false;
+ }
+ if (screenPosition == getDisplayLength() - 1) {
return false;
}
- Line q = (Line) nextFrag;
- ArrayList<Cell> newCells = new ArrayList<Cell>(this.cells.size() +
- q.cells.size());
- newCells.addAll(this.cells);
- newCells.addAll(q.cells);
- this.cells = newCells;
- ((Line) q.nextFrag).prevFrag = this;
- nextFrag = q.nextFrag;
+ if (position < rawText.length()) {
+ screenPosition += StringUtils.width(rawText.codePointAt(position));
+ position += Character.charCount(rawText.codePointAt(position));
+ }
+ assert (position <= rawText.length());
return true;
}
/**
- * See if this Fragment can be joined with the previous Fragment in list.
+ * Go to the first column of this line.
*
- * @return true if the join was possible, false otherwise
+ * @return true if the cursor position changed
*/
- public boolean isPrevJoinable() {
- if ((prevFrag != null) && (prevFrag instanceof Line)) {
+ public boolean home() {
+ if (position > 0) {
+ position = 0;
+ screenPosition = 0;
return true;
}
return false;
}
/**
- * Join this Fragment with the previous Fragment in list.
+ * Go to the last column of this line.
*
- * @return true if the join was successful, false otherwise
+ * @return true if the cursor position changed
*/
- public boolean joinPrev() {
- if ((prevFrag == null) || !(prevFrag instanceof Line)) {
- return false;
+ public boolean end() {
+ if (screenPosition != getDisplayLength() - 1) {
+ position = rawText.length();
+ screenPosition = StringUtils.width(rawText.toString());
+ return true;
}
- Line p = (Line) prevFrag;
- ArrayList<Cell> newCells = new ArrayList<Cell>(this.cells.size() +
- p.cells.size());
- newCells.addAll(p.cells);
- newCells.addAll(this.cells);
- this.cells = newCells;
- ((Line) p.prevFrag).nextFrag = this;
- prevFrag = p.prevFrag;
- return true;
+ return false;
}
/**
- * Set the next Fragment in the list. Note that this performs no sanity
- * checking or modifications on fragment; this function can break
- * connectivity in the list.
- *
- * @param fragment the next Fragment, or null
+ * Delete the character under the cursor.
*/
- public void setNext(Fragment fragment) {
- nextFrag = fragment;
- }
+ public void del() {
+ assert (words.size() > 0);
- /**
- * Set the previous Fragment in the list. Note that this performs no
- * sanity checking or modifications on fragment; this function can break
- * connectivity in the list.
- *
- * @param fragment the previous Fragment, or null
- */
- public void setPrev(Fragment fragment) {
- prevFrag = fragment;
- }
+ if (screenPosition < getDisplayLength()) {
+ int n = Character.charCount(rawText.codePointAt(position));
+ for (int i = 0; i < n; i++) {
+ rawText.deleteCharAt(position);
+ }
+ }
- /**
- * Split this Fragment into two. 'this' Fragment will contain length
- * cells, 'this.next()' will contain (getCellCount() - length) cells.
- *
- * @param length the number of cells to leave in this Fragment
- * @throws IndexOutOfBoundsException if length is negative, or 0, greater
- * than (getCellCount() - 1)
- */
- public void split(final int length) {
- // Create the next node
- Line q = new Line();
- q.nextFrag = nextFrag;
- q.prevFrag = this;
- ((Line) nextFrag).prevFrag = q;
- nextFrag = q;
-
- // Split cells
- q.cells = new ArrayList<Cell>(cells.size() - length);
- q.cells.addAll(cells.subList(length, cells.size()));
- cells = cells.subList(0, length);
- }
+ // 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(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;
+ }
+ }
- /**
- * Insert a new Fragment at a position, splitting the contents of this
- * Fragment into two around it. 'this' Fragment will contain the cells
- * between 0 and index, 'this.next()' will be the inserted fragment, and
- * 'this.next().next()' will contain the cells between 'index' and
- * getCellCount() - 1.
- *
- * @param index the number of cells to leave in this Fragment
- * @param fragment the Fragment to insert
- * @throws IndexOutOfBoundsException if length is negative, or 0, greater
- * than (getCellCount() - 1)
- */
- public void split(final int index, Fragment fragment) {
- // Create the next node and insert into the list.
- Line q = new Line();
- q.nextFrag = nextFrag;
- q.nextFrag.setPrev(q);
- q.prevFrag = fragment;
- fragment.setNext(q);
- fragment.setPrev(this);
- nextFrag = fragment;
-
- // Split cells
- q.cells = new ArrayList<Cell>(cells.size() - index);
- q.cells.addAll(cells.subList(index, cells.size()));
- cells = cells.subList(0, index);
+ if (left()) {
+ del();
+ }
}
/**
- * Insert a new Fragment before this one.
+ * Insert a character at the cursor.
*
- * @param fragment the Fragment to insert
+ * @param ch the character to insert
*/
- public void insert(Fragment fragment) {
- fragment.setNext(this);
- fragment.setPrev(prevFrag);
- prevFrag.setNext(fragment);
- prevFrag = fragment;
+ 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();
}
/**
- * Append a new Fragment at the end of this one.
+ * Replace a character at the cursor.
*
- * @param fragment the Fragment to append
+ * @param ch the character to replace
*/
- public void append(Fragment fragment) {
- fragment.setNext(nextFrag);
- fragment.setPrev(this);
- nextFrag.setPrev(fragment);
- nextFrag = fragment;
+ 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();
}
/**
- * Delete this Fragment from the list, and return its next().
+ * Determine string position from screen position.
*
- * @return this Fragment's next(), or null if it was at the end of the
- * list
+ * @param screenPosition the position on screen
+ * @return the equivalent position in text
*/
- public Fragment deleteGetNext() {
- Fragment result = nextFrag;
- nextFrag.setPrev(prevFrag);
- prevFrag.setNext(nextFrag);
- prevFrag = null;
- nextFrag = null;
- return result;
+ 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());
}
/**
- * Delete this Fragment from the list, and return its prev().
- *
- * @return this Fragment's next(), or null if it was at the beginning of
- * the list
+ * Trim trailing whitespace from line, repositioning cursor if needed.
*/
- public Fragment deleteGetPrev() {
- Fragment result = prevFrag;
- nextFrag.setPrev(prevFrag);
- prevFrag.setNext(nextFrag);
- prevFrag = null;
- nextFrag = null;
- return result;
+ 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();
}
/**
- * Get the anchor position.
+ * Handle the tab character.
*
- * @return the anchor number
+ * @param tabSize the tab stop size
*/
- public int getAnchor() {
- return lineNumber;
+ public void tab(final int tabSize) {
+ if (tabSize > 0) {
+ do {
+ addChar(' ');
+ } while ((screenPosition % tabSize) != 0);
+ }
}
/**
- * Set the anchor position.
+ * Handle the backtab (shift-tab) character.
*
- * @param x the new anchor number
+ * @param tabSize the tab stop size
*/
- public void setAnchor(final int x) {
- lineNumber = x;
+ 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) == ' '));
+ }
}
}