[project @ 2005-07-20 23:27:27 by adrianl]

2D scrolling of text areas/frames; First cut at selection in textareas; Further text editing actions (Word left/right; Page up/down; Cut block; Delete line start/end)

svn path=/import/netsurf/; revision=1812

1 files changed, 435 insertions, 96 deletions

diff --git a/desktop/textinput.c b/desktop/textinput.c
index e4017b435..9b8b94929 100644
--- a/desktop/textinput.c
+++ b/desktop/textinput.c
@@ -14,6 +14,7 @@
  */
 
 #include <assert.h>
+#include <ctype.h>
 #include <string.h>
 
 #include "netsurf/desktop/browser.h"
@@ -48,14 +49,22 @@ static void input_update_display(struct browser_window *bw, struct box *input,
 		bool redraw);
 static bool textbox_insert(struct browser_window *bw, struct box *text_box,
 		unsigned char_offset, const char *utf8, unsigned utf8_len);
-static bool textbox_delete(struct browser_window *bw, struct box *text_box,
-		unsigned char_offset, unsigned utf8_len);
+static bool textbox_delete(struct box *text_box, unsigned char_offset,
+		unsigned utf8_len);
 static struct box *textarea_insert_break(struct browser_window *bw,
 		struct box *text_box, size_t char_offset);
-static bool delete_handler(struct box *b, int offset, size_t length,
-		void *handle);
+static bool delete_handler(struct box *b, int offset, size_t length);
+static struct box *line_start(struct box *text_box);
+static struct box *line_end(struct box *text_box);
+static struct box *line_above(struct box *text_box);
+static struct box *line_below(struct box *text_box);
+static bool textarea_cut(struct browser_window *bw,
+		struct box *start_box, unsigned start_idx,
+		struct box *end_box, unsigned end_idx);
 static void textarea_reflow(struct browser_window *bw, struct box *textarea,
 		struct box *inline_container);
+static bool word_left(const char *text, int *poffset, int *pchars);
+static bool word_right(const char *text, int len, int *poffset, int *pchars);
 
 
 /**
@@ -249,7 +258,7 @@ void browser_window_textarea_callback(struct browser_window *bw,
 			int prev_offset = char_offset;
 			char_offset = utf8_prev(text_box->text, char_offset);
 
-			textbox_delete(bw, text_box, char_offset, prev_offset - char_offset);
+			textbox_delete(text_box, char_offset, prev_offset - char_offset);
 		}
 		reflow = true;
 		break;
@@ -287,8 +296,7 @@ void browser_window_textarea_callback(struct browser_window *bw,
 			/* delete a character */
 			int next_offset = utf8_next(text_box->text, text_box->length,
 				char_offset);
-			textbox_delete(bw, text_box, char_offset,
-				next_offset - char_offset);
+			textbox_delete(text_box, char_offset, next_offset - char_offset);
 		}
 		reflow = true;
 		break;
@@ -306,48 +314,39 @@ void browser_window_textarea_callback(struct browser_window *bw,
 		break;
 
 	case 21: {	/* Ctrl + U */
-			struct box *next;
-
-			/* run back to start of line */
-			while (text_box->prev && text_box->prev->type == BOX_TEXT)
-				text_box = text_box->prev;
-
-			/* run forwards to end */
-			next = text_box->next;
-			while (next && next->type == BOX_TEXT) {
-				box_unlink_and_free(text_box);
-					text_box = next;
-				next = text_box->next;
-			}
-
-			/* can we take out this last inline and and the following BR? */
-			if (next && next->type == BOX_BR && next->next) {
-				box_unlink_and_free(text_box);
+		struct box *start_box = line_start(text_box);
+		struct box *end_box = line_end(text_box);
 
-				/* place caret at start of next box */
-				text_box = next->next;
-				box_unlink_and_free(next);
-			}
-			else
-				textbox_delete(bw, text_box, 0, text_box->length);
+		textarea_cut(bw, start_box, 0, end_box, end_box->length);
 
-			char_offset = 0;
-			reflow = true;
-		}
-		break;
+		text_box = start_box;
+		char_offset = 0;
+		reflow = true;
+	}
+	break;
 
 	case 22:	/* Ctrl + V */
 		gui_paste_from_clipboard(bw->window,
 			box_x + inline_container->x + text_box->x + pixel_offset,
 			box_y + inline_container->y + text_box->y);
-		break;
 
-	case 24:	/* Ctrl + X */
-		if (gui_copy_to_clipboard(bw->sel)) {
-			selection_traverse(bw->sel, delete_handler, bw);
+		/* screen updated and caret repositioned already */
+		return;
+
+	case 24: {	/* Ctrl + X */
+		int start_idx, end_idx;
+		struct box *start_box = selection_get_start(bw->sel, &start_idx);
+		struct box *end_box = selection_get_end(bw->sel, &end_idx);
+		if (start_box && end_box) {
+			selection_clear(bw->sel, false);
+			textarea_cut(bw, start_box, start_idx, end_box, end_idx);
+
+			text_box = start_box;
+			char_offset = start_idx;
 			reflow = true;
 		}
-		break;
+	}
+	break;
 
 	case KEY_RIGHT:
 		if ((unsigned int) char_offset < text_box->length) {
@@ -398,14 +397,12 @@ void browser_window_textarea_callback(struct browser_window *bw,
 		return;
 
 	case KEY_LINE_START:
-		while (text_box->prev && text_box->prev->type == BOX_TEXT)
-			text_box = text_box->prev;
+		text_box = line_start(text_box);
 		char_offset = 0;
 		break;
 
 	case KEY_LINE_END:
-		while (text_box->next && text_box->next->type == BOX_TEXT)
-			text_box = text_box->next;
+		text_box = line_end(text_box);
 		char_offset = text_box->length;
 		break;
 
@@ -425,41 +422,101 @@ void browser_window_textarea_callback(struct browser_window *bw,
 		char_offset = text_box->length;
 		break;
 
-	case KEY_WORD_LEFT:
-//		while () {
-//		}
-		break;
+	case KEY_WORD_LEFT: {
+		bool start_of_word = (char_offset <= 0 ||
+				isspace(text_box->text[char_offset - 1]));
 
-	case KEY_WORD_RIGHT:
-//		while () {
-//		}
-		break;
+		while (!word_left(text_box->text, &char_offset, NULL)) {
+			struct box *prev = NULL;
+
+			assert(char_offset == 0);
+
+			if (start_of_word) {
+				/* find the preceding non-BR box */
+				prev = text_box->prev;
+				while (prev && prev->type == BOX_BR)
+					prev = prev->prev;
+			}
+
+			if (!prev) {
+				/* just stay at the start of this box */
+				break;
+			}
+
+			text_box = prev;
+			char_offset = prev->length;
+		}
+	}
+	break;
+
+	case KEY_WORD_RIGHT: {
+		bool in_word = (char_offset < text_box->length &&
+				!isspace(text_box->text[char_offset]));
+
+		while (!word_right(text_box->text, text_box->length,
+				&char_offset, NULL)) {
+			struct box *next = text_box->next;
+
+			/* find the next non-BR box */
+			while (next && next->type == BOX_BR)
+				next = next->next;
+
+			if (!next) {
+				/* just stay at the end of this box */
+				char_offset = text_box->length;
+				break;
+			}
+
+			text_box = next;
+			char_offset = 0;
+
+			if (in_word &&
+				text_box->length > 0 &&
+				!isspace(text_box->text[0])) {
+				/* just stay at the start of this box */
+				break;
+			}
+		}
+	}
+	break;
+
+	case KEY_PAGE_UP: {
+		int nlines = (textarea->height / text_box->height) - 1;
+
+		while (nlines-- > 0)
+			text_box = line_above(text_box);
 
-	case KEY_PAGE_UP:
-//		while () {
-//		}
 		if (char_offset > text_box->length)
 			char_offset = text_box->length;
-		break;
+	}
+	break;
+
+	case KEY_PAGE_DOWN: {
+		int nlines = (textarea->height / text_box->height) - 1;
+		while (nlines-- > 0)
+			text_box = line_below(text_box);
 
-	case KEY_PAGE_DOWN:
+		/* vague attempt to keep the caret at the same horizontal position,
+		   given that the code currently cannot support it being beyond the
+		   end of a line */
 
-//		while () {
-//		}
 		if (char_offset > text_box->length)
 			char_offset = text_box->length;
-		break;
+	}
+	break;
 
 	case KEY_DELETE_LINE_START:
-		textbox_delete(bw, text_box, 0, char_offset);
+		textarea_cut(bw, line_start(text_box), 0, text_box, char_offset);
+		char_offset = 0;
 		reflow = true;
 		break;
 
-	case KEY_DELETE_LINE_END:
-		textbox_delete(bw, text_box, char_offset,
-			text_box->length - char_offset);
+	case KEY_DELETE_LINE_END: {
+		struct box *end_box = line_end(text_box);
+		textarea_cut(bw, text_box, char_offset, end_box, end_box->length);
 		reflow = true;
-		break;
+	}
+	break;
 
 	default:
 		return;
@@ -673,17 +730,13 @@ void browser_window_input_callback(struct browser_window *bw,
 			return;
 
 		box_offset += utf8_len;
-
-		nsfont_width(text_box->style, text_box->text,
-				text_box->length, &text_box->width);
 		changed = true;
 
 	} else switch (key) {
 	case KEY_DELETE_LEFT: {
 			int prev_offset;
 
-			if (box_offset == 0)
-				return;
+			if (box_offset <= 0) return;
 
 			/* Gadget */
 			prev_offset = form_offset;
@@ -702,12 +755,8 @@ void browser_window_input_callback(struct browser_window *bw,
 			/* Go to the previous valid UTF-8 character */
 			box_offset = utf8_prev(text_box->text, box_offset);
 
-			textbox_delete(bw, text_box, box_offset,
-					prev_offset - box_offset);
-
-			nsfont_width(text_box->style, text_box->text,
-					text_box->length, &text_box->width);
-
+			textbox_delete(text_box, box_offset,
+				prev_offset - box_offset);
 			changed = true;
 		}
 		break;
@@ -735,12 +784,8 @@ void browser_window_input_callback(struct browser_window *bw,
 			next_offset = utf8_next(text_box->text, text_box->length,
 								box_offset);
 
-			textbox_delete(bw, text_box, box_offset,
+			textbox_delete(text_box, box_offset,
 					next_offset - box_offset);
-
-			nsfont_width(text_box->style, text_box->text,
-					text_box->length, &text_box->width);
-
 			changed = true;
 		}
 		break;
@@ -797,8 +842,6 @@ void browser_window_input_callback(struct browser_window *bw,
 		input->gadget->value[0] = 0;
 		input->gadget->length = 0;
 		form_offset = 0;
-
-		text_box->width = 0;
 		changed = true;
 		break;
 
@@ -806,7 +849,10 @@ void browser_window_input_callback(struct browser_window *bw,
 		gui_paste_from_clipboard(bw->window,
 			box_x + input->children->x + text_box->x + pixel_offset,
 			box_y + input->children->y + text_box->y);
-		break;
+
+		/* screen updated and caret repositioned already */
+		return;
+
 
 	case KEY_RIGHT:
 		/* Text box */
@@ -837,6 +883,67 @@ void browser_window_input_callback(struct browser_window *bw,
 		form_offset = input->gadget->length;
 		break;
 
+	case KEY_WORD_LEFT: {
+		int nchars;
+		/* Text box */
+		if (word_left(input->gadget->value, &form_offset, &nchars)) {
+			/* Gadget */
+			while (box_offset > 0 && nchars-- > 0)
+				box_offset = utf8_prev(text_box->text, box_offset);
+		} else {
+			box_offset = 0;
+			form_offset = 0;
+		}
+	}
+	break;
+
+	case KEY_WORD_RIGHT: {
+		int nchars;
+		/* Text box */
+		if (word_right(input->gadget->value, input->gadget->length,
+				&form_offset, &nchars)) {
+			/* Gadget */
+			const char *text = text_box->text;
+			unsigned len = text_box->length;
+			while (box_offset < len && nchars-- > 0)
+				box_offset = utf8_next(text, len, box_offset);
+		} else {
+			box_offset = text_box->length;
+			form_offset = input->gadget->length;
+		}
+	}
+	break;
+
+	case KEY_DELETE_LINE_START:
+
+		if (box_offset <= 0) return;
+
+		/* Text box */
+		textbox_delete(text_box, 0, box_offset);
+		box_offset = 0;
+
+		/* Gadget */
+		memmove(input->gadget->value,
+			input->gadget->value + form_offset,
+			(input->gadget->length - form_offset) + 1); /* inc NUL */
+		input->gadget->length -= form_offset;
+		form_offset = 0;
+		changed = true;
+		break;
+
+	case KEY_DELETE_LINE_END:
+
+		if (box_offset >= text_box->length)
+			return;
+
+		/* Text box */
+		textbox_delete(text_box, box_offset, text_box->length - box_offset);
+		/* Gadget */
+		input->gadget->length = form_offset;
+		input->gadget->value[form_offset] = 0;
+		changed = true;
+		break;
+
 	default:
 		return;
 	}
@@ -1133,13 +1240,8 @@ bool browser_window_input_paste_text(struct browser_window *bw,
 		utf8 = p;
 	}
 
-	if (update) {
-
-		nsfont_width(text_box->style, text_box->text, text_box->length,
-			&text_box->width);
-
+	if (update)
 		input_update_display(bw, input, form_offset, box_offset, false, true);
-	}
 
 	return success;
 }
@@ -1165,6 +1267,10 @@ void input_update_display(struct browser_window *bw, struct box *input,
 	int box_x, box_y;
 	int dx;
 
+	if (redraw)
+		nsfont_width(text_box->style, text_box->text, text_box->length,
+			&text_box->width);
+
 	box_coords(input, &box_x, &box_y);
 
 	nsfont_width(text_box->style, text_box->text, box_offset,
@@ -1172,7 +1278,7 @@ void input_update_display(struct browser_window *bw, struct box *input,
 	dx = text_box->x;
 	text_box->x = 0;
 	if (input->width < text_box->width &&
-			input->width / 2 < pixel_offset) {
+			input->width / 2 < (int)pixel_offset) {
 		text_box->x = input->width / 2 - pixel_offset;
 		if (text_box->x < input->width - text_box->width)
 			text_box->x = input->width - text_box->width;
@@ -1245,14 +1351,12 @@ bool textbox_insert(struct browser_window *bw, struct box *text_box,
 /**
  * Delete a number of chars from a text box
  *
- * \param  bw           browser window
  * \param  text_box     text box
  * \param  char_offset  offset within text box (bytes) of first char to delete
  * \param  utf8_len     length (bytes) of chars to be deleted
  */
 
-bool textbox_delete(struct browser_window *bw, struct box *text_box,
-		unsigned char_offset, unsigned utf8_len)
+bool textbox_delete(struct box *text_box, unsigned char_offset, unsigned utf8_len)
 {
 	unsigned prev_offset = char_offset + utf8_len;
 	if (prev_offset <= text_box->length) {
@@ -1271,10 +1375,89 @@ bool textbox_delete(struct browser_window *bw, struct box *text_box,
 }
 
 
-bool delete_handler(struct box *b, int offset, size_t length, void *handle)
+/**
+ * Delete some text from a box, or delete the box in its entirety
+ *
+ * \param  b       box
+ * \param  offset  start offset of text to be deleted (in bytes)
+ * \param  length  length of text to be deleted
+ * \return true iff successful
+ */
+
+bool delete_handler(struct box *b, int offset, size_t length)
+{
+	if (offset <= 0 && length >= b->length) {
+		/* remove the entire box */
+		box_unlink_and_free(b);
+		return true;
+	}
+	else {
+		return textbox_delete(b, offset, length);
+	}
+}
+
+
+/**
+ * Locate the first inline box at the start of this line
+ *
+ * \param  text_box  text box from which to start searching
+ */
+
+struct box *line_start(struct box *text_box)
+{
+	while (text_box->prev && text_box->prev->type == BOX_TEXT)
+		text_box = text_box->prev;
+	return text_box;
+}
+
+
+/**
+ * Locate the last inline box in this line
+ *
+ * \param  text_box  text box from which to start searching
+ */
+
+struct box *line_end(struct box *text_box)
 {
-	struct browser_window *bw = handle;
-	return textbox_delete(bw, b, offset, length);
+	while (text_box->next && text_box->next->type == BOX_TEXT)
+		text_box = text_box->next;
+	return text_box;
+}
+
+
+/**
+ * Backtrack to the start of the previous line, if there is one.
+ */
+
+struct box *line_above(struct box *text_box)
+{
+	struct box *prev;
+
+	text_box = line_start(text_box);
+
+	prev = text_box->prev;
+	while (prev && prev->type == BOX_BR)
+		prev = prev->prev;
+
+	return prev ? line_start(prev) : text_box;
+}
+
+
+/**
+ * Advance to the start of the next line, if there is one.
+ */
+
+struct box *line_below(struct box *text_box)
+{
+	struct box *next;
+
+	text_box = line_end(text_box);
+
+	next = text_box->next;
+	while (next && next->type == BOX_BR)
+		next = next->next;
+
+	return next ? next : text_box;
 }
 
 
@@ -1323,6 +1506,86 @@ struct box *textarea_insert_break(struct browser_window *bw, struct box *text_bo
 
 
 /**
+ * Cut a range of text to the global clipboard.
+ *
+ * \param  bw  browser window
+ * \param  start_box  text box at start of range
+ * \param  start_idx  index (bytes) within start box
+ * \param  end_box    text box at end of range
+ * \param  end_idx    index (bytes) within end box
+ */
+
+bool textarea_cut(struct browser_window *bw,
+		struct box *start_box, unsigned start_idx,
+		struct box *end_box, unsigned end_idx)
+{
+	struct box *box = start_box;
+	bool success = true;
+	bool del = true;
+
+	if (!gui_empty_clipboard())
+		return false;
+
+	if (!start_idx && (!start_box->prev || start_box->prev->type == BOX_BR)) {
+		/* deletion would leave two adjacent BRs, so just collapse
+		   the start box to an empty TEXT rather than deleting it */
+		del = false;
+	}
+
+	while (box && box != end_box) {
+		/* read before deletion, in case the whole box goes */
+		struct box *next = box->next;
+
+		if (box->type == BOX_BR) {
+			if (!gui_add_to_clipboard("\n", 1, false)) {
+				gui_commit_clipboard();
+				return false;
+			}
+			box_unlink_and_free(box);
+		}
+		else {
+			/* append box text to clipboard and then delete it */
+			if (!gui_add_to_clipboard(box->text + start_idx,
+					box->length - start_idx, box->space)) {
+				gui_commit_clipboard();
+				return false;
+			}
+
+			if (del) {
+				if (!delete_handler(box, start_idx,
+					box->length - start_idx)) {
+					gui_commit_clipboard();
+					return false;
+				}
+			}
+			else
+				textbox_delete(box, start_idx, box->length - start_idx);
+		}
+
+		del = true;
+		start_idx = 0;
+		box = next;
+	}
+
+	/* and the last box */
+	if (box) {
+		if (gui_add_to_clipboard(box->text + start_idx, end_idx, box->space)) {
+			if (del) {
+				if (!delete_handler(box, start_idx, end_idx - start_idx))
+					success = false;
+			}
+			else
+				textbox_delete(box, start_idx, end_idx - start_idx);
+		}
+		else
+			success = false;
+	}
+
+	return gui_commit_clipboard() ? success : false;
+}
+
+
+/**
  * Reflow textarea preserving width and height
  *
  * \param  bw                browser window
@@ -1344,3 +1607,79 @@ void textarea_reflow(struct browser_window *bw, struct box *textarea,
 	layout_calculate_descendant_bboxes(textarea);
 }
 
+
+/**
+ * Move to the start of the word containing the given character position,
+ * or the start of the preceding word if already at the start of this one.
+ *
+ * \param  text     UTF-8 text string
+ * \param  poffset  offset of caret within string (updated on exit)
+ * \param  pchars   receives the number of characters skipped
+ * \return true iff the start of a word was found before/at the string start
+ */
+
+bool word_left(const char *text, int *poffset, int *pchars)
+{
+	int offset = *poffset;
+	bool success = false;
+	int nchars = 0;
+
+	while (offset > 0) {
+		offset = utf8_prev(text, offset);
+		nchars++;
+		if (!isspace(text[offset])) break;
+	}
+
+	while (offset > 0) {
+		int prev = utf8_prev(text, offset);
+		success = true;
+		if (isspace(text[prev]))
+			break;
+		offset = prev;
+		nchars++;
+	}
+
+	*poffset = offset;
+	if (pchars) *pchars = nchars;
+
+	return success;
+}
+
+
+/**
+ * Move to the start of the first word following the given character position.
+ *
+ * \param  text     UTF-8 text string
+ * \param  len      length of string in bytes
+ * \param  poffset  offset of caret within string (updated on exit)
+ * \param  pchars   receives the number of characters skipped
+ * \return true iff the start of a word was found before the string end
+ */
+
+bool word_right(const char *text, int len, int *poffset, int *pchars)
+{
+	int offset = *poffset;
+	bool success = false;
+	int nchars = 0;
+
+	while (offset < len) {
+		if (isspace(text[offset])) break;
+		offset = utf8_next(text, len, offset);
+		nchars++;
+	}
+
+	while (offset < len) {
+		offset = utf8_next(text, len, offset);
+		nchars++;
+		if (offset < len && !isspace(text[offset])) {
+			success = true;
+			break;
+		}
+	}
+
+	*poffset = offset;
+	if (pchars) *pchars = nchars;
+
+	return success;
+}
+