Track newlines at end of paragraphs

4 files changed, 109 insertions, 23 deletions

diff --git a/src/debugger.c b/src/debugger.c
index 32cea14..15012e6 100644
--- a/src/debugger.c
+++ b/src/debugger.c
@@ -145,6 +145,10 @@ static void debug_text_para(Paragraph *para, cairo_t *cr, double *ypos,
 
 		}
 	}
+
+	if ( get_newline_at_end(para) ) {
+		plot_text(cr, ypos, fontdesc, "Ends with newline");
+	}
 }
 
 
diff --git a/src/frame.c b/src/frame.c
index 8c6acc6..8f1e3ec 100644
--- a/src/frame.c
+++ b/src/frame.c
@@ -51,6 +51,7 @@ struct _paragraph
 	enum para_type   type;
 	double           height;
 	float            space[4];
+	int              newline_at_end;
 
 	/* For PARA_TYPE_TEXT */
 	int              n_runs;
@@ -351,6 +352,17 @@ void wrap_paragraph(Paragraph *para, PangoContext *pc, double w,
 	para->height += para->space[2] + para->space[3];
 }
 
+int get_newline_at_end(Paragraph *para)
+{
+	return para->newline_at_end;
+}
+
+
+void set_newline_at_end(Paragraph *para)
+{
+	para->newline_at_end = 1;
+}
+
 
 void add_run(Paragraph *para, SCBlock *scblock, SCBlock *macro_real,
              size_t offs_bytes, size_t len_bytes, PangoFontDescription *fdesc,
@@ -521,10 +533,25 @@ Paragraph *last_open_para(struct frame *fr)
 void close_last_paragraph(struct frame *fr)
 {
 	if ( fr->paras == NULL ) return;
+	if ( fr->paras[fr->n_paras-1]->type != PARA_TYPE_TEXT ) {
+		printf("Closing a non-text paragraph!\n");
+	}
 	fr->paras[fr->n_paras-1]->open = 0;
 }
 
 
+int last_para_available_for_text(struct frame *fr)
+{
+	Paragraph *last_para;
+	if ( fr->paras == NULL ) return 0;
+	last_para = fr->paras[fr->n_paras-1];
+	if ( last_para->type == PARA_TYPE_TEXT ) {
+		if ( last_para->open ) return 1;
+	}
+	return 0;
+}
+
+
 static void render_from_surf(cairo_surface_t *surf, cairo_t *cr,
                              double w, double h, int border)
 {
@@ -909,16 +936,39 @@ void insert_text_in_paragraph(Paragraph *para, size_t offs, const char *t)
 }
 
 
-static void delete_paragraph(struct frame *fr, int p)
+static void fixup_subsq(int first_para, struct frame *fr, SCBlock *scblock,
+                        size_t del_len)
+{
+	int i;
+
+	for ( i=first_para; i<fr->n_paras; i++ ) {
+		int j;
+		int done = 0;
+		Paragraph *para = fr->paras[i];
+		if ( para->type != PARA_TYPE_TEXT ) continue;
+		for ( j=0; j<para->n_runs; j++ ) {
+			if ( para->runs[j].scblock != scblock) {
+				done = 1;
+				break;
+				}
+			printf("subsq para %p run %i del %i\n", para, i, (int)del_len);
+			para->runs[j].scblock_offs_bytes -= del_len;
+		}
+		if ( done ) break;
+	}
+}
+
+
+static void delete_text_paragraph(Paragraph *para, int p, struct frame *fr)
 {
 	int i;
-	Paragraph *para = fr->paras[p];
 
 	/* Delete the corresponding SC */
 	for ( i=0; i<para->n_runs; i++ ) {
 
 		int j;
 		struct text_run *run;
+		size_t nl = 0;
 
 		run = &para->runs[i];
 
@@ -927,12 +977,22 @@ static void delete_paragraph(struct frame *fr, int p)
 			continue;
 		}
 
+		/* Find the newline at the end of the paragraph, if it
+		 * exists */
+		size_t toffs = run->scblock_offs_bytes + run->len_bytes;
+		if ( sc_block_contents(run->scblock)[toffs] == '\n' ) {
+			printf("Found newline when deleting paragraph\n");
+			nl = 1;
+		} else {
+			printf("No newline when deleting paragraph\n");
+		}
+
 		/* Delete from the corresponding SC block */
 		scblock_delete_text(run->scblock, run->scblock_offs_bytes,
-		                    run->scblock_offs_bytes + run->len_bytes);
+		                    run->scblock_offs_bytes + run->len_bytes+nl);
 
 		/* Fix up the offsets of the subsequent text runs */
-		size_t del_len = run->len_bytes;
+		size_t del_len = run->len_bytes + nl;
 		run->len_bytes -= del_len;
 		for ( j=i+1; j<para->n_runs; j++ ) {
 			if ( para->runs[j].scblock == run->scblock ) {
@@ -940,6 +1000,28 @@ static void delete_paragraph(struct frame *fr, int p)
 			}
 			para->runs[j].para_offs_bytes -= del_len;
 		}
+
+		/* ... and in subsequent paragraphs, if they're from the same
+		 * SCBlock */
+		fixup_subsq(p+1, fr, run->scblock, del_len);
+
+	}
+}
+
+
+static void delete_paragraph(struct frame *fr, int p)
+{
+	int i;
+	Paragraph *para = fr->paras[p];
+
+	if ( para->type != PARA_TYPE_TEXT ) {
+		if ( para->macro_real_scblock != NULL ) {
+			sc_block_delete(&fr->scblocks, para->macro_real_scblock);
+		} else {
+			sc_block_delete(&fr->scblocks, para->scblock);
+		}
+	} else {
+		delete_text_paragraph(para, p, fr);
 	}
 
 	/* Delete the paragraph from the frame */
@@ -1088,22 +1170,9 @@ size_t delete_text_in_paragraph(struct frame *fr, int npara, size_t offs1, ssize
 
 		/* ... and in subsequent paragraphs, if they're from the same
 		 * SCBlock */
-		for ( i=npara+1; i<fr->n_paras; i++ ) {
-			int j;
-			int done = 0;
-			Paragraph *para = fr->paras[i];
-			if ( para->type != PARA_TYPE_TEXT ) continue;
-			for ( j=0; j<para->n_runs; j++ ) {
-				if ( para->runs[j].scblock != run->scblock) {
-					done = 1;
-					break;
-				}
-				printf("subsq para %p run %i del %i\n", para, i, (int)del_len);
-				para->runs[j].scblock_offs_bytes -= del_len;
-			}
-			if ( done ) break;
-		}
+		fixup_subsq(npara+1, fr, run->scblock, del_len);
 
+		offs1 -= del_len;
 		offs2 -= del_len;
 
 	}
diff --git a/src/frame.h b/src/frame.h
index c52df27..1e46239 100644
--- a/src/frame.h
+++ b/src/frame.h
@@ -123,6 +123,7 @@ extern double total_height(struct frame *fr);
 extern Paragraph *last_open_para(struct frame *fr);
 extern Paragraph *current_para(struct frame *fr);
 extern void close_last_paragraph(struct frame *fr);
+extern int last_para_available_for_text(struct frame *fr);
 extern void show_para(Paragraph *p);
 extern void set_para_spacing(Paragraph *para, float space[4]);
 
@@ -130,6 +131,9 @@ extern double paragraph_height(Paragraph *para);
 extern void render_paragraph(cairo_t *cr, Paragraph *para, ImageStore *is,
                              enum is_size isz);
 
+extern int get_newline_at_end(Paragraph *para);
+extern void set_newline_at_end(Paragraph *para);
+
 extern void add_run(Paragraph *para, SCBlock *scblock, SCBlock *macro_real,
                     size_t offs_bytes, size_t len_bytes,
                     PangoFontDescription *fdesc, double col[4]);
diff --git a/src/sc_interp.c b/src/sc_interp.c
index df00d5e..df559e1 100644
--- a/src/sc_interp.c
+++ b/src/sc_interp.c
@@ -887,6 +887,13 @@ static int in_macro(SCInterpreter *scin)
 }
 
 
+static void set_newline_at_end_last_para(struct frame *fr)
+{
+	if ( fr->paras == NULL ) return;
+	set_newline_at_end(fr->paras[fr->n_paras-1]);
+}
+
+
 /* Add the SCBlock to the text in 'frame', at the end */
 static int add_text(struct frame *fr, PangoContext *pc, SCBlock *bl,
                     PangoLanguage *lang, int editable, SCInterpreter *scin)
@@ -895,7 +902,6 @@ static int add_text(struct frame *fr, PangoContext *pc, SCBlock *bl,
 	size_t start, len_bytes;
 	PangoFontDescription *fontdesc;
 	double *col;
-	int just_closed = 0;
 	struct sc_state *st = &scin->state[scin->j];
 	SCBlock *mrb;
 
@@ -921,20 +927,23 @@ static int add_text(struct frame *fr, PangoContext *pc, SCBlock *bl,
 		}
 
 		if ( text[start] == '\n' ) {
-			if ( just_closed ) {
+			if ( !last_para_available_for_text(fr) ) {
+				/* Add an empty paragraph */
 				Paragraph *para = last_open_para(fr);
 				add_run(para, bl, mrb, start, 0, fontdesc, col);
 				set_para_spacing(para, st->paraspace);
+				set_newline_at_end(para);
 			}
+			/* Close this paragraph */
+			set_newline_at_end_last_para(fr);
 			close_last_paragraph(fr);
 			start += 1;
-			just_closed = 1;
 		} else  {
+			/* Just add some text */
 			Paragraph *para = last_open_para(fr);
 			add_run(para, bl, mrb, start, len, fontdesc, col);
 			set_para_spacing(para, st->paraspace);
 			start += len;
-			just_closed = 0;
 		}
 
 	} while ( start < len_bytes );