Track the newlines at ends of paragraphs directly

No more messing around searching for \n characters

5 files changed, 101 insertions, 97 deletions

diff --git a/src/frame.c b/src/frame.c
index 8f1e3ec..010394f 100644
--- a/src/frame.c
+++ b/src/frame.c
@@ -51,7 +51,7 @@ struct _paragraph
 	enum para_type   type;
 	double           height;
 	float            space[4];
-	int              newline_at_end;
+	SCBlock         *newline_at_end;
 
 	/* For PARA_TYPE_TEXT */
 	int              n_runs;
@@ -352,15 +352,15 @@ void wrap_paragraph(Paragraph *para, PangoContext *pc, double w,
 	para->height += para->space[2] + para->space[3];
 }
 
-int get_newline_at_end(Paragraph *para)
+SCBlock *get_newline_at_end(Paragraph *para)
 {
 	return para->newline_at_end;
 }
 
 
-void set_newline_at_end(Paragraph *para)
+void set_newline_at_end(Paragraph *para, SCBlock *bl)
 {
-	para->newline_at_end = 1;
+	para->newline_at_end = bl;
 }
 
 
@@ -917,6 +917,27 @@ void insert_text_in_paragraph(Paragraph *para, size_t offs, const char *t)
 		return;
 	}
 
+	if ( (sc_block_name(run->scblock) != NULL)
+	  && (strcmp(sc_block_name(run->scblock), "newpara") == 0) )
+	{
+
+		SCBlock *nnp;
+		printf("Inserting into newpara block...\n");
+
+		/* Add a new \newpara block after this one */
+		nnp = sc_block_append(run->scblock, "newpara",
+		                      NULL, NULL, NULL);
+
+		/* The first \newpara block becomes a normal anonymous block */
+		sc_block_set_name(run->scblock, NULL);
+
+		if ( para->newline_at_end == run->scblock ) {
+			para->newline_at_end = nnp;
+			printf("Replaced the newpara block\n");
+		}
+
+	}
+
 	/* Translate paragraph offset for insertion into SCBlock offset */
 	run_offs = offs - run->para_offs_bytes;
 	scblock_offs = run_offs + run->scblock_offs_bytes;
@@ -1214,9 +1235,7 @@ void merge_paragraphs(struct frame *fr, int para)
 {
 	Paragraph *p1, *p2;
 	struct text_run *runs_new;
-	int i, j;
-	size_t offs;
-	SCBlock *scblock;
+	int i;
 	SCBlock *n;
 
 	if ( para >= fr->n_paras-1 ) {
@@ -1241,49 +1260,14 @@ void merge_paragraphs(struct frame *fr, int para)
 	}
 	p1->runs = runs_new;
 
-	/* Locate the newline which we have just deleted. */
-	scblock = p1->runs[p1->n_runs-1].scblock;
-	n = sc_block_next(scblock);
-	offs = p1->runs[p1->n_runs-1].scblock_offs_bytes;
-	offs += p1->runs[p1->n_runs-1].len_bytes;
-
-	if ( sc_block_contents(scblock)[offs] == '\n' ) {
-
-		scblock_delete_text(scblock, offs, offs+1);
-
-		/* Update the SC offset of any run from this SCBlock */
-		for ( i=para+1; i<fr->n_paras; i++ ) {
-			int done = 0;
-			if ( fr->paras[i]->type != PARA_TYPE_TEXT ) break;
-			for ( j=0; j<fr->paras[i]->n_runs; j++ ) {
-				struct text_run *run = &fr->paras[i]->runs[j];
-				if ( run->scblock == scblock ) {
-					run->scblock_offs_bytes -= 1;
-				} else {
-					done = 1;
-					break;
-				}
-			}
-			if ( done ) break;
-		}
-
-	} else if ( (n!=NULL) && (sc_block_contents(n)[0] == '\n') ) {
-
-		/* It's in the following SCBlock instead */
-
-		const char *c = sc_block_contents(n);
-		if ( strlen(c) == 1 ) {
-			SCBlock *ss = scblock;
-			sc_block_delete(&scblock, n);
-			assert(ss == scblock);
-		} else {
-			scblock_delete_text(n, 0, 1);
-		}
+	/* Delete the \newpara block to unite the paragraphs */
+	n = get_newline_at_end(p1);
+	assert(n != NULL);
+	sc_block_delete(&fr->scblocks, n);
 
-	} else {
-		printf("Couldn't find newline!\n");
-		printf("Have '%s'\n", sc_block_contents(scblock)+offs);
-	}
+	/* The end of the united paragraph should now be the end of the
+	 * second one */
+	set_newline_at_end(p1, get_newline_at_end(p2));
 
 	for ( i=0; i<p2->n_runs; i++ ) {
 
@@ -1308,13 +1292,6 @@ void merge_paragraphs(struct frame *fr, int para)
 }
 
 
-static char *s_strdup(const char *a)
-{
-	if ( a == NULL ) return NULL;
-	return strdup(a);
-}
-
-
 static SCBlock *split_text_paragraph(struct frame *fr, int pn, size_t pos,
                                      PangoContext *pc)
 {
@@ -1425,10 +1402,10 @@ static SCBlock *split_text_paragraph(struct frame *fr, int pn, size_t pos,
 		pnew->runs[0].scblock_offs_bytes = 0;
 	}
 
-	/* Add a newline after the end of the first paragraph's SC */
-	sc_block_append(rr->scblock, s_strdup(sc_block_name(rr->scblock)),
-	                             s_strdup(sc_block_options(rr->scblock)),
-	                             strdup("\n"), NULL);
+	/* Add a \newpara after the end of the first paragraph's SC */
+	set_newline_at_end(para,
+	                   sc_block_append(rr->scblock, strdup("newpara"),
+	                                   NULL, NULL, NULL));
 
 	pnew->open = para->open;
 	para->open = 0;
diff --git a/src/frame.h b/src/frame.h
index 1e46239..dbe79ef 100644
--- a/src/frame.h
+++ b/src/frame.h
@@ -131,8 +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 SCBlock *get_newline_at_end(Paragraph *para);
+extern void set_newline_at_end(Paragraph *para, SCBlock *bl);
+extern void check_run(struct frame *fr, int pn);
 
 extern void add_run(Paragraph *para, SCBlock *scblock, SCBlock *macro_real,
                     size_t offs_bytes, size_t len_bytes,
diff --git a/src/sc_interp.c b/src/sc_interp.c
index df559e1..255fe91 100644
--- a/src/sc_interp.c
+++ b/src/sc_interp.c
@@ -887,13 +887,6 @@ 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)
@@ -916,35 +909,12 @@ static int add_text(struct frame *fr, PangoContext *pc, SCBlock *bl,
 	start = 0;
 	do {
 
-		char *para_end;
-		size_t len;
-
-		para_end = strchr(text+start, '\n');
-		if ( para_end == NULL ) {
-			len = strlen(text+start);
-		} else {
-			len = para_end - (text+start);
-		}
+		size_t len = strlen(text+start);
 
-		if ( text[start] == '\n' ) {
-			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;
-		} 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;
-		}
+		Paragraph *para = last_open_para(fr);
+		add_run(para, bl, mrb, start, len, fontdesc, col);
+		set_para_spacing(para, st->paraspace);
+		start += len;
 
 	} while ( start < len_bytes );
 
@@ -1001,6 +971,14 @@ static int check_outputs(SCBlock *bl, SCInterpreter *scin)
 		set_frame(scin, fr);
 		maybe_recurse_after(scin, child);
 
+	} else if ( strcmp(name, "newpara")==0 ) {
+		struct frame *fr = sc_interp_get_frame(scin);
+		Paragraph *para = last_open_para(fr);
+		/* Add a dummy run which we can type into */
+		add_run(para, bl, NULL, 0, 0, fr->fontdesc, fr->col);
+		set_newline_at_end(para, bl);
+		close_last_paragraph(fr);
+
 	} else {
 		return 0;
 	}
diff --git a/src/sc_parse.c b/src/sc_parse.c
index 56ebcaf..79e59a0 100644
--- a/src/sc_parse.c
+++ b/src/sc_parse.c
@@ -296,6 +296,9 @@ char *serialise_sc_block(const SCBlock *bl)
 
 	if ( bl->name == NULL ) {
 		strcat(a, bl->contents);
+	} else if ( strcmp(bl->name, "newpara") == 0 ) {
+		strcat(a, "\n");
+
 	} else {
 
 		strcat(a, "\\");
@@ -503,6 +506,41 @@ static size_t read_block(const char *sc, char **pname, char **options,
 }
 
 
+static void separate_newlines(SCBlock *bl)
+{
+	while ( bl != NULL ) {
+
+		char *npos;
+		const char *contents = sc_block_contents(bl);
+
+		if ( contents != NULL ) {
+			npos = strchr(contents, '\n');
+			if ( npos != NULL ) {
+				SCBlock *nb = NULL;
+				if ( npos == contents ) {
+					bl->name = strdup("newpara");
+					bl->contents = NULL;
+					nb = bl;
+				} else {
+					sc_block_append(bl, strdup("newpara"), NULL, NULL, &nb);
+				}
+				if ( strlen(npos+1) > 0 ) {
+					sc_block_append(nb, NULL, NULL, strdup(npos+1), &nb);
+				}
+				npos[0] = '\0';
+			}
+		}
+
+		if ( sc_block_child(bl) != NULL ) {
+			separate_newlines(sc_block_child(bl));
+		}
+
+		bl = sc_block_next(bl);
+
+	}
+}
+
+
 SCBlock *sc_parse(const char *sc)
 {
 	SCBlock *bl;
@@ -601,10 +639,19 @@ SCBlock *sc_parse(const char *sc)
 		j = 0;
 	}
 
+	separate_newlines(blf);
+
 	return blf;
 }
 
 
+void sc_block_set_name(SCBlock *bl, char *nam)
+{
+	free(bl->name);
+	bl->name = nam;
+}
+
+
 void sc_block_set_options(SCBlock *bl, char *opt)
 {
 	free(bl->options);
diff --git a/src/sc_parse.h b/src/sc_parse.h
index 4775996..41a1112 100644
--- a/src/sc_parse.h
+++ b/src/sc_parse.h
@@ -65,6 +65,7 @@ extern void sc_block_unlink(SCBlock **top, SCBlock *deleteme);
 extern SCBlock *find_last_child(SCBlock *bl);
 
 
+extern void sc_block_set_name(SCBlock *bl, char *nam);
 extern void sc_block_set_options(SCBlock *bl, char *opt);
 extern void sc_block_set_contents(SCBlock *bl, char *con);
 extern void sc_insert_text(SCBlock *b1, size_t o1, const char *t);