Remove macro_real_block and friends, and delete text based on SCBlocks instead of runs

macro_real_block was a pain because it meant we needed to look somewhere
else every time we needed the SCBlock for something.  The new way is to
have two SCBlocks for each run, one which is the block from the flow of
the actual document (i.e. for blocks within macros, this is the
macro_real_block, otherwise it's the same as before).  The second block
("rscblock") is whichever run actually contains the text for the run.
It might be from the document, within the macro definition or within the
macro's "\contents".

6 files changed, 527 insertions, 201 deletions

diff --git a/src/frame.c b/src/frame.c
index fc2fefc..20b3ded 100644
--- a/src/frame.c
+++ b/src/frame.c
@@ -35,13 +35,10 @@
 #include "frame.h"
 #include "imagestore.h"
 
-
 struct text_run
 {
-	SCBlock              *scblock;
-	SCBlock              *macro_real_block;
-	SCBlock              *macro_contents;
-	int                   macro_editable;
+	SCBlock              *scblock;   /* If macro, this is \macro */
+	SCBlock              *rscblock;  /* The block with the actual text */
 	size_t                para_offs_bytes;  /* Offset from start of paragraph */
 	size_t                len_bytes;
 	PangoFontDescription *fontdesc;
@@ -65,7 +62,6 @@ struct _paragraph
 	/* For anything other than PARA_TYPE_TEXT
 	 * (for text paragraphs, these things are in the runs) */
 	SCBlock         *scblock;
-	SCBlock         *macro_real_scblock;
 
 	/* For PARA_TYPE_IMAGE */
 	char            *filename;
@@ -321,7 +317,7 @@ void wrap_paragraph(Paragraph *para, PangoContext *pc, double w,
 		const char *run_text;
 		guint16 r, g, b;
 
-		run_text = sc_block_contents(para->runs[i].scblock);
+		run_text = sc_block_contents(para->runs[i].rscblock);
 
 		attr = pango_attr_font_desc_new(para->runs[i].fontdesc);
 		attr->start_index = pos;
@@ -377,10 +373,9 @@ void set_newline_at_end(Paragraph *para, SCBlock *bl)
 }
 
 
-void add_run(Paragraph *para, SCBlock *scblock,
-             SCBlock *macro_real, SCBlock *contents_top,
+void add_run(Paragraph *para, SCBlock *scblock, SCBlock *rscblock,
              size_t len_bytes, PangoFontDescription *fdesc,
-             double col[4], int macro_editable)
+             double col[4])
 {
 	struct text_run *runs_new;
 
@@ -398,9 +393,7 @@ void add_run(Paragraph *para, SCBlock *scblock,
 
 	para->runs = runs_new;
 	para->runs[para->n_runs].scblock = scblock;
-	para->runs[para->n_runs].macro_real_block = macro_real;
-	para->runs[para->n_runs].macro_contents = contents_top;
-	para->runs[para->n_runs].macro_editable = macro_editable;
+	para->runs[para->n_runs].rscblock = rscblock;
 	para->runs[para->n_runs].para_offs_bytes = para->offset_last;
 	para->offset_last += len_bytes;
 	para->runs[para->n_runs].len_bytes = len_bytes;
@@ -463,7 +456,7 @@ Paragraph *insert_paragraph(struct frame *fr, int pos)
 }
 
 
-void add_callback_para(struct frame *fr, SCBlock *bl, SCBlock *mr,
+void add_callback_para(struct frame *fr, SCBlock *bl,
                        double w, double h,
                        SCCallbackDrawFunc draw_func,
                        SCCallbackClickFunc click_func, void *bvp,
@@ -479,7 +472,6 @@ void add_callback_para(struct frame *fr, SCBlock *bl, SCBlock *mr,
 
 	pnew->type = PARA_TYPE_CALLBACK;
 	pnew->scblock = bl;
-	pnew->macro_real_scblock = mr;
 	pnew->cb_w = w;
 	pnew->cb_h = h;
 	pnew->draw_func = draw_func;
@@ -948,13 +940,13 @@ size_t pos_trail_to_offset(Paragraph *para, size_t offs, int trail)
 		return 0;
 	}
 
-	if ( (sc_block_name(run->scblock) != NULL)
-	  && (strcmp(sc_block_name(run->scblock), "newpara") == 0) )
+	if ( (sc_block_name(run->rscblock) != NULL)
+	  && (strcmp(sc_block_name(run->rscblock), "newpara") == 0) )
 	{
 		return 0;
 	}
 
-	if ( sc_block_contents(run->scblock) == NULL ) {
+	if ( sc_block_contents(run->rscblock) == NULL ) {
 		fprintf(stderr, "pos_trail_to_offset: No contents "
 		        "(%p name=%s, options=%s)\n",
 		        run->scblock, sc_block_name(run->scblock),
@@ -963,7 +955,7 @@ size_t pos_trail_to_offset(Paragraph *para, size_t offs, int trail)
 	}
 
 	/* Get the text for the run */
-	run_text = sc_block_contents(run->scblock);
+	run_text = sc_block_contents(run->rscblock);
 
 	/* Turn  the paragraph offset into a run offset */
 	run_offs = offs - run->para_offs_bytes;
@@ -998,13 +990,6 @@ void insert_text_in_paragraph(Paragraph *para, size_t offs, const char *t)
 	}
 	run = &para->runs[nrun];
 
-	if ( run->macro_real_block != NULL ) {
-		if ( !run->macro_editable ) {
-			printf("Not inserting text into a macro block.\n");
-			return;
-		}
-	}
-
 	if ( (sc_block_name(run->scblock) != NULL)
 	  && (strcmp(sc_block_name(run->scblock), "newpara") == 0) )
 	{
@@ -1028,7 +1013,7 @@ void insert_text_in_paragraph(Paragraph *para, size_t offs, const char *t)
 
 	/* Translate paragraph offset for insertion into SCBlock offset */
 	run_offs = offs - run->para_offs_bytes;
-	sc_insert_text(run->scblock, run_offs, t);
+	sc_insert_text(run->rscblock, run_offs, t);
 
 	/* Update length of this run */
 	ins_len = strlen(t);
@@ -1041,118 +1026,524 @@ void insert_text_in_paragraph(Paragraph *para, size_t offs, const char *t)
 }
 
 
-static void delete_text_paragraph(Paragraph *para, int p, struct frame *fr)
+static SCBlock *pos_to_rscblock(struct frame *fr, struct edit_pos p)
+{
+	int run;
+	size_t paraoffs;
+	Paragraph *para;
+
+	para = fr->paras[p.para];
+
+	if ( para->type != PARA_TYPE_TEXT ) {
+		return NULL;
+	}
+
+	paraoffs = pos_trail_to_offset(para, p.pos, p.trail);
+
+	run = which_run(para, paraoffs);
+	assert(run < para->n_runs);
+
+	return para->runs[run].rscblock;
+}
+
+
+
+static SCBlock *pos_to_scblock(struct frame *fr, struct edit_pos p,
+                               enum para_type *type)
+{
+	int run;
+	size_t paraoffs;
+	Paragraph *para;
+
+	para = fr->paras[p.para];
+	if ( type != NULL ) {
+		*type = para->type;
+	}
+
+	if ( para->type != PARA_TYPE_TEXT ) {
+		return para->scblock;
+	}
+
+	paraoffs = pos_trail_to_offset(para, p.pos, p.trail);
+
+	run = which_run(para, paraoffs);
+	assert(run < para->n_runs);
+
+	return para->runs[run].scblock;
+}
+
+
+static size_t pos_to_offset(struct frame *fr, struct edit_pos p)
+{
+	int run;
+	size_t paraoffs;
+	Paragraph *para;
+
+	para = fr->paras[p.para];
+	if ( para->type != PARA_TYPE_TEXT ) {
+		return 0;
+	}
+
+	paraoffs = pos_trail_to_offset(para, p.pos, p.trail);
+
+	run = which_run(para, paraoffs);
+	assert(run < para->n_runs);
+
+	return paraoffs - para->runs[run].para_offs_bytes;
+}
+
+
+static int pos_to_run_number(struct frame *fr, struct edit_pos p)
+{
+	int run;
+	size_t paraoffs;
+	Paragraph *para;
+
+	para = fr->paras[p.para];
+	if ( para->type != PARA_TYPE_TEXT ) {
+		return 0;
+	}
+
+	paraoffs = pos_trail_to_offset(para, p.pos, p.trail);
+
+	run = which_run(para, paraoffs);
+	assert(run < para->n_runs);
+
+	return run;
+}
+
+
+/* Reduce para_offs_bytes for all runs in "para" after "start" by "del" */
+static void update_subsq_para_offsets(Paragraph *para, int start, size_t del)
 {
 	int i;
 
-	/* Delete the corresponding SC */
-	for ( i=0; i<para->n_runs; i++ ) {
+	for ( i=start+1; i<para->n_runs; i++ ) {
+		para->runs[i].para_offs_bytes -= del;
+	}
+}
 
-		int j;
-		struct text_run *run;
 
-		run = &para->runs[i];
+static size_t delete_run(Paragraph *para, int nrun)
+{
+	size_t del;
 
-		if ( run->macro_real_block != NULL ) {
-			printf("Not deleting text from macro block\n");
-			continue;
-		}
+	printf("deleting run %i of %i from para %p\n", nrun, para->n_runs, para);
+	del = para->runs[nrun].len_bytes;
+	memmove(&para->runs[nrun], &para->runs[nrun+1],
+	        (para->n_runs-1)*sizeof(struct text_run));
+	para->n_runs--;
 
-		if ( (sc_block_name(run->scblock) != NULL)
-		  && (strcmp(sc_block_name(run->scblock), "newpara") == 0) )
-		{
-			sc_block_delete(&fr->scblocks, run->scblock);
-			return;
-		}
+	return del;
+}
 
-		/* Delete from the corresponding SC block */
-		scblock_delete_text(run->scblock, 0, run->len_bytes);
 
-		/* Fix up the offsets of the subsequent text runs */
-		size_t del_len = run->len_bytes;
-		run->len_bytes -= del_len;
-		for ( j=i+1; j<para->n_runs; j++ ) {
-			para->runs[j].para_offs_bytes -= del_len;
+static Paragraph *scan_runs_for_scblock(struct frame *fr, int pn1, int pn2,
+                                        SCBlock *bl, int *run)
+{
+	int i;
+	for ( i=pn1; i<=pn2; i++ ) {
+		int j;
+		for ( j=0; j<fr->paras[i]->n_runs; j++ ) {
+			if ( fr->paras[i]->runs[j].rscblock == bl ) {
+				*run = j;
+				return fr->paras[i];
+			}
 		}
+	}
+	return NULL;
+}
+
+
+static Paragraph *find_run_for_scblock_next(struct frame *fr, int pn1, int pn2,
+                                            SCBlock *bl, int *run)
+{
+	if ( sc_block_child(bl) != NULL ) {
+		Paragraph *para;
+		para = find_run_for_scblock_next(fr, pn1, pn2,
+		                                 sc_block_child(bl), run);
+		if ( para != NULL ) return para;
+	}
+
+	do {
+		Paragraph *para;
+		para = scan_runs_for_scblock(fr, pn1, pn2, bl, run);
+		if ( para != NULL ) return para;
+		bl = sc_block_next(bl);
+	} while ( bl != NULL );
+
+	return NULL;
+}
+
+
+/* Find the run which contains the text from "bl",
+ * taking into account that it might be a child block, for example:
+ *   {some text}
+ *   \italic          <---- bl points here
+ *      {more text}   <---- but this block is referenced by the run
+ *   {final text}
+ */
+static Paragraph *find_run_for_scblock(struct frame *fr, int pn1, int pn2,
+                                       SCBlock *bl, int *run)
+{
+	Paragraph *para;
+
+	show_sc_block(bl, "searching ");
+	para = scan_runs_for_scblock(fr, pn1, pn2, bl, run);
+	if ( para != NULL ) return para;
 
+	if ( sc_block_child(bl) != NULL ) {
+		para = find_run_for_scblock_next(fr, pn1, pn2, sc_block_child(bl), run);
+		if ( para != NULL ) return para;
 	}
+
+	return NULL;
 }
 
 
-static void delete_paragraph(struct frame *fr, int p)
+static int paragraph_number(struct frame *fr, Paragraph *p, int *err)
 {
 	int i;
-	Paragraph *para = fr->paras[p];
+	for ( i=0; i<fr->n_paras; i++ ) {
+		if ( fr->paras[i] == p ) return i;
+	}
+	fprintf(stderr, "Couldn't find paragraph %p\n", p);
+	*err = 1;
+	return 0;
+}
+
+
+static size_t delete_run_for_scblock(struct frame *fr,
+                                     Paragraph *p1, Paragraph *p2, SCBlock *bl)
+{
+	int pn1, pn2;
+	int err = 0;
+	size_t del;
+	Paragraph *para;
+	int run;
+
+	pn1 = paragraph_number(fr, p1, &err);
+	pn2 = paragraph_number(fr, p2, &err);
+	if ( err ) return 0;
+
+	para = find_run_for_scblock(fr, pn1, pn2, bl, &run);
+	if ( para == NULL ) {
+		fprintf(stderr, "Couldn't find block %p between paragraphs %p and %p\n",
+		        bl, p1, p2);
+		return 0;
+	}
+
+	del = delete_run(para, run);
+	update_subsq_para_offsets(para, run, del);
+
+	return del;
+}
+
+
+static signed int merge_paragraph_runs(Paragraph *p1, Paragraph *p2)
+{
+	struct text_run *runs_new;
+	int i, spos;
+
+	/* All the runs from p2 get added to p1 */
+	runs_new = realloc(p1->runs,
+	                   (p1->n_runs+p2->n_runs)*sizeof(struct text_run));
+	if ( runs_new == NULL ) {
+		fprintf(stderr, "Failed to allocate merged runs.\n");
+		return -1;
+	}
+	p1->runs = runs_new;
+
+	assert(p1->runs[p1->n_runs-1].scblock == get_newline_at_end(p1));
+	p1->n_runs--;  /* Chop off the run corresponding to \newpara */
+	spos = p1->n_runs;
+
+	/* 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++ ) {
+
+		size_t offs;
+
+		p1->runs[p1->n_runs] = p2->runs[i];
+
+		offs = p1->runs[p1->n_runs-1].para_offs_bytes;
+		offs += p1->runs[p1->n_runs-1].len_bytes;
+		p1->runs[p1->n_runs].para_offs_bytes = offs;
+
+		p1->n_runs++;
 
-	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);
 	}
+	free(p2->runs);
+	free(p2);
 
-	/* Delete the paragraph from the frame */
-	free_paragraph(fr->paras[p]);
-	for ( i=p; i<fr->n_paras-1; i++ ) {
+	return spos;
+}
+
+
+void merge_paragraphs(struct frame *fr, int para)
+{
+	Paragraph *p1, *p2;
+	int i;
+	SCBlock *n;
+
+	if ( para >= fr->n_paras-1 ) {
+		printf("Paragraph number too high to merge.\n");
+		return;
+	}
+
+	p1 = fr->paras[para];
+	p2 = fr->paras[para+1];
+
+	if ( (p1->type != PARA_TYPE_TEXT) || (p2->type != PARA_TYPE_TEXT) ) {
+		printf("Trying to merge non-text paragraphs.\n");
+		return;
+	}
+
+	/* Delete the \newpara block to unite the paragraphs */
+	n = get_newline_at_end(p1);
+	assert(n != NULL);
+
+	if ( sc_block_delete(&fr->scblocks, n) ) {
+		fprintf(stderr, "Failed to delete paragraph end sentinel.\n");
+		return;
+	}
+
+	merge_paragraph_runs(p1, p2);
+
+	for ( i=para+1; i<fr->n_paras-1; i++ ) {
 		fr->paras[i] = fr->paras[i+1];
 	}
 	fr->n_paras--;
 }
 
 
+
+static void merge_paragraphs_by_newpara(struct frame *fr, SCBlock *np)
+{
+	int i;
+	Paragraph *p1;
+	Paragraph *p2;
+
+	for ( i=0; i<fr->n_paras-1; i++ ) {
+		if ( fr->paras[i]->newline_at_end == np ) {
+
+			int j;
+			signed int spos;
+
+			p1 = fr->paras[i];
+			p2 = fr->paras[i+1];
+
+			printf("-------------------------------\n");
+			show_para(p1);
+			printf("---x--------x------------------\n");
+			show_para(p2);
+			spos = merge_paragraph_runs(p1, p2);
+			if ( spos < 0 ) {
+				fprintf(stderr, "Failed to merge paragraphs\n");
+				return;
+			}
+			printf("-------------------------------\n");
+			show_para(p1);
+
+			for ( j=i+1; j<fr->n_paras-1; j++ ) {
+				fr->paras[j] = fr->paras[j+1];
+			}
+			fr->n_paras--;
+
+			return;
+
+		}
+	}
+
+	fprintf(stderr, "Couldn't find paragraphs to merge by newpara\n");
+}
+
+
+static int find_block_inside(SCBlock *needle, SCBlock *bl)
+{
+	if ( needle == bl ) return 1;
+
+	if ( sc_block_child(bl) != NULL ) {
+		if ( find_block_inside(needle, sc_block_child(bl)) ) return 1;
+	}
+
+	if ( sc_block_next(bl) != NULL ) {
+		if ( find_block_inside(needle, sc_block_next(bl)) ) return 1;
+	}
+
+	return 0;
+}
+
+
+/* Return true if "top" either IS "child", or contains "child" somewhere
+ * underneath, even if via a macro expansion */
+static int block_is_under(SCBlock *needle, SCBlock *top)
+{
+	if ( needle == top ) return 1;
+
+	if ( sc_block_child(top) != NULL ) {
+		if ( find_block_inside(needle, sc_block_child(top)) ) return 1;
+	}
+
+	/* Do not look at top->next here */
+
+	return 0;
+}
+
+
 void delete_text_from_frame(struct frame *fr, struct edit_pos p1, struct edit_pos p2,
                             double wrapw)
 {
 	int i;
-	size_t del = 0;
+	SCBlock *p1scblock, *p2scblock;
+	SCBlock *p1rscblock, *p2rscblock;
+	enum para_type type1, type2;
+	SCBlock *scblock;
 
 	sort_positions(&p1, &p2);
 
 	printf("para %i offs %ld\n", p1.para, p1.pos);
 	printf("para %i offs %li\n", p2.para, p2.pos);
 
-	for ( i=p1.para; i<=p2.para; i++ ) {
+	/* Find SC positions for start and end */
+	p1scblock = pos_to_scblock(fr, p1, &type1);
+	p2scblock = pos_to_scblock(fr, p2, &type2);
+	p1rscblock = pos_to_rscblock(fr, p1);
+	p2rscblock = pos_to_rscblock(fr, p2);
 
-		size_t start;
-		ssize_t finis;
+	printf("SCBlocks %p to %p\n", p1scblock, p2scblock);
+	//show_sc_blocks(p1scblock);
 
-		printf("para %i\n", i);
+	if ( (p1scblock == p2scblock) && (type1 == PARA_TYPE_TEXT) ) {
 
-		Paragraph *para = fr->paras[i];
+		size_t del;
+		int p1run;
+		size_t p1offs, p2offs;
+		printf("Simple case, one SCBlock\n");
 
-		if ( i == p1.para ) {
-			start = pos_trail_to_offset(para, p1.pos, p1.trail);
-		} else {
-			start = 0;
-		}
+		assert(type1 == type2);
+
+		/* Remove the text and update the run length */
+		p1offs = pos_to_offset(fr, p1);
+		p2offs = pos_to_offset(fr, p2);
+		del = scblock_delete_text(p1scblock, p1offs, p2offs);
+
+		p1run = pos_to_run_number(fr, p1);
+		fr->paras[p1.para]->runs[p1run].len_bytes -= del;
+
+		/* Update the paragraph offsets of subsequent runs */
+		update_subsq_para_offsets(fr->paras[p1.para], p1run, del);
+
+		wrap_paragraph(fr->paras[p1.para], NULL, wrapw, 0, 0);
+
+		return;
+	}
 
-		if ( i == p2.para ) {
-			finis = pos_trail_to_offset(para, p2.pos, p2.trail);
+	/* Starting point for iteration over blocks in middle of range.
+	 * Record this now, because p1scblock might be about to get deleted */
+	scblock = sc_block_next(p1scblock);
+
+	/* First SCBlock in range: delete whole thing or second half */
+	printf("First block %p\n", p1scblock);
+	if ( type1 == PARA_TYPE_TEXT ) {
+
+		size_t p1offs = pos_to_offset(fr, p1);
+		int p1run = pos_to_run_number(fr, p1);
+		printf("  offs %li\n", (long int)p1offs);
+		if ( p1offs != 0 ) {
+			size_t del;
+			printf("Partial delete\n");
+			printf("contents '%s'\n", sc_block_contents(p1rscblock));
+			printf("from offs %li\n", (long int)p1offs);
+			del = scblock_delete_text(p1rscblock, p1offs, -1);
+			fr->paras[p1.para]->runs[p1run].len_bytes -= del;
+			update_subsq_para_offsets(fr->paras[p1.para], p1run, del);
 		} else {
-			finis = -1;
+			printf("Deleting the whole text SCBlock\n");
+			sc_block_delete(&fr->scblocks, p1scblock);
+			delete_run(fr->paras[p1.para], p1run);
 		}
 
-		if ( (start == 0) && (finis == -1) ) {
-			printf("deleting para %i\n", i);
-			delete_paragraph(fr, i);
-			p2.para--;
-			i--;
+	} else {
+		printf("Deleting the whole non-text SCBlock\n");
+		sc_block_delete(&fr->scblocks, p1scblock);
+	}
+
+	/* Delete all the complete SCBlocks in the middle of the range */
+	if ( !block_is_under(p2scblock, scblock) ) {
+		do {
+
+			SCBlock *next;
+
+			/* For each SC block in middle of range: */
+			printf("Deleting %p\n", scblock);
+			if ( scblock == NULL ) {
+				fprintf(stderr, "nothing?\n");
+				break;
+			}
+			printf("name is '%s'\n", sc_block_name(scblock));
+			if ( (sc_block_name(scblock) != NULL)
+			  && (strcmp(sc_block_name(scblock), "newpara") == 0) )
+			{
+				/* Deleting newpara block, merge the paragraphs */
+				merge_paragraphs_by_newpara(fr, scblock);
+
+			}
+
+			next = sc_block_next(scblock);
+			delete_run_for_scblock(fr, fr->paras[p1.para],
+			                       fr->paras[p2.para], scblock);
+			sc_block_delete(&fr->scblocks, scblock);
+
+			scblock = next;
+
+		} while ( !block_is_under(p2scblock, scblock) );
+	}
+
+	/* Last SCBlock in range: delete whole thing or first half */
+	printf("Last block %p (%s)\n", p2scblock, sc_block_name(p2scblock));
+	if ( type2 == PARA_TYPE_TEXT ) {
+		size_t len;
+		size_t p2offs = pos_to_offset(fr, p2);
+		int p2run = pos_to_run_number(fr, p2);
+		printf("  offs %li\n", (long int)p2offs);
+		if ( sc_block_contents(p2rscblock) != NULL ) {
+			len = strlen(sc_block_contents(p2rscblock));
 		} else {
-			printf("deleting from %ld to %ld\n", start, finis);
-			del += delete_text_in_paragraph(fr, i, start, finis);
-			wrap_paragraph(para, NULL, wrapw, 0, 0);
+			len = 0;
 		}
-
+		printf("  len %li\n", (long int)len);
+		if ( (len > 0) && (p2offs == len) ) {
+			printf("Deleting the whole text SCBlock\n");
+			printf("deleting block %p\n", p2scblock);
+			show_sc_block(p2scblock, "");
+			sc_block_delete(&fr->scblocks, p2scblock);
+			delete_run(fr->paras[p2.para], p2run);
+		} else if ( p2offs > 0 ) {
+			size_t del;
+			printf("Partial delete\n");
+			printf("contents '%s'\n", sc_block_contents(p2rscblock));
+			printf("up to offs %li\n", (long int)p2offs);
+			del = scblock_delete_text(p2rscblock, 0, p2offs);
+			fr->paras[p2.para]->runs[p2run].len_bytes -= del;
+			update_subsq_para_offsets(fr->paras[p2.para], p2run, del);
+		} /* else do nothing */
+	} else {
+		printf("Deleting the whole non-text SCBlock\n");
+		sc_block_delete(&fr->scblocks, p2scblock);
 	}
 
-	/* If we deleted across a paragraph, merge paragraphs */
-	if ( p1.para != p2.para ) {
-		merge_paragraphs(fr, p1.para);
-		wrap_paragraph(fr->paras[p1.para], NULL, wrapw, 0, 0);
+	/* If any paragraphs have been deleted, this will wrap too many
+	 * paragraphs, but it doesn't matter as long as we don't wrap
+	 * past the end of the frame's contents. */
+	for ( i=p1.para; i<=p2.para; i++ ) {
+		if ( i >= fr->n_paras ) break;
+		printf("Wrapping para %i (%p)\n", i, fr->paras[i]);
+		wrap_paragraph(fr->paras[i], NULL, wrapw, 0, 0);
 	}
+	printf("All done.\n");
 }
 
 
@@ -1200,13 +1591,6 @@ size_t delete_text_in_paragraph(struct frame *fr, int npara, size_t offs1, ssize
 		assert(de >= 0);  /* Otherwise nrun2 was too big */
 		if ( ds == de ) continue;
 
-		if ( run->macro_real_block != NULL ) {
-			if ( !run->macro_editable ) {
-				printf("Not deleting inside macro block!\n");
-				continue;
-			}
-		}
-
 		/* Delete from the corresponding SC block */
 		scblock_offs1 = ds;
 		scblock_offs2 = de;
@@ -1231,7 +1615,7 @@ size_t delete_text_in_paragraph(struct frame *fr, int npara, size_t offs1, ssize
 
 static char *run_text(struct text_run *run)
 {
-	return strndup(sc_block_contents(run->scblock), run->len_bytes);
+	return strndup(sc_block_contents(run->rscblock), run->len_bytes);
 }
 
 
@@ -1263,82 +1647,13 @@ void show_para(Paragraph *p)
 }
 
 
-void merge_paragraphs(struct frame *fr, int para)
-{
-	Paragraph *p1, *p2;
-	struct text_run *runs_new;
-	int i;
-	SCBlock *n;
-
-	if ( para >= fr->n_paras-1 ) {
-		printf("Paragraph number too high to merge.\n");
-		return;
-	}
-
-	p1 = fr->paras[para];
-	p2 = fr->paras[para+1];
-
-	if ( (p1->type != PARA_TYPE_TEXT) || (p2->type != PARA_TYPE_TEXT) ) {
-		printf("Trying to merge non-text paragraphs.\n");
-		return;
-	}
-
-	/* Delete the \newpara block to unite the paragraphs */
-	n = get_newline_at_end(p1);
-	assert(n != NULL);
-
-	if ( sc_block_delete(&fr->scblocks, n) ) {
-		if ( p1->runs[p1->n_runs-1].macro_contents != NULL ) {
-			if  ( sc_block_delete(&p1->runs[p1->n_runs-1].macro_contents, n) ) {
-				fprintf(stderr, "Failed to delete paragraph end sentinel.\n");
-				return;
-			}
-		}
-	}
-
-	/* All the runs from p2 get added to p1 */
-	runs_new = realloc(p1->runs,
-	                   (p1->n_runs+p2->n_runs)*sizeof(struct text_run));
-	if ( runs_new == NULL ) {
-		fprintf(stderr, "Failed to allocate merged runs.\n");
-		return;
-	}
-	p1->runs = runs_new;
-
-	/* 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++ ) {
-
-		size_t offs;
-
-		p1->runs[p1->n_runs] = p2->runs[i];
-
-		offs = p1->runs[p1->n_runs-1].para_offs_bytes;
-		offs += p1->runs[p1->n_runs-1].len_bytes;
-		p1->runs[p1->n_runs].para_offs_bytes = offs;
-
-		p1->n_runs++;
-
-	}
-	free(p2->runs);
-	free(p2);
-
-	for ( i=para+1; i<fr->n_paras-1; i++ ) {
-		fr->paras[i] = fr->paras[i+1];
-	}
-	fr->n_paras--;
-}
-
-
 static void check_para(Paragraph *para)
 {
 	int i;
 	for ( i=0; i<para->n_runs; i++ ) {
 		const char *run_text;
-		if ( sc_block_contents(para->runs[i].scblock) == NULL ) continue;
-		run_text = sc_block_contents(para->runs[i].scblock);
+		if ( sc_block_contents(para->runs[i].rscblock) == NULL ) continue;
+		run_text = sc_block_contents(para->runs[i].rscblock);
 		if ( strlen(run_text) < para->runs[i].len_bytes ) {
 			printf("found a wrong run\n");
 			printf("run %i, para offs %li text '%s'\n", i,
@@ -1397,7 +1712,7 @@ static SCBlock *split_text_paragraph(struct frame *fr, int pn, size_t pos,
 			printf("splitting at end of para\n");
 			pnew->runs[0].para_offs_bytes = 0;
 			pnew->runs[0].scblock = rr->scblock;
-			pnew->runs[0].macro_real_block = rr->macro_real_block;
+			pnew->runs[0].rscblock = rr->rscblock;
 			pnew->runs[0].para_offs_bytes = 0;
 			pnew->runs[0].len_bytes = 0;
 			pnew->runs[0].fontdesc = pango_font_description_copy(rr->fontdesc);
@@ -1424,7 +1739,7 @@ static SCBlock *split_text_paragraph(struct frame *fr, int pn, size_t pos,
 
 		/* First run of the new paragraph contains the leftover text */
 		pnew->runs[0].scblock = rr->scblock;
-		pnew->runs[0].macro_real_block = rr->macro_real_block;
+		pnew->runs[0].rscblock = rr->rscblock;
 		pnew->runs[0].para_offs_bytes = 0;
 		pnew->runs[0].len_bytes = rr->len_bytes - run_offs;
 		printf("%i - %i\n", (int)rr->len_bytes, (int)run_offs);
@@ -1456,14 +1771,14 @@ static SCBlock *split_text_paragraph(struct frame *fr, int pn, size_t pos,
 	para->n_runs = run+1;
 
 	/* If the first and second paragraphs have the same SCBlock, split it */
-	if ( (rr->scblock != NULL) && (rr->scblock == pnew->runs[0].scblock) ) {
+	if ( (rr->rscblock != NULL) && (rr->rscblock == pnew->runs[0].rscblock) ) {
 
 		printf("splitting SCBlock at %i\n", (int)run_offs);
-		printf("old block: '%s'\n", sc_block_contents(rr->scblock));
-		pnew->runs[0].scblock = sc_block_split(rr->scblock, run_offs);
-		printf("new block 1: '%s'\n", sc_block_contents(rr->scblock));
-		printf("new block 2: '%s'\n", sc_block_contents(pnew->runs[0].scblock));
-		printf("run %p block %p\n", &pnew->runs[0], pnew->runs[0].scblock);
+		printf("old block: '%s'\n", sc_block_contents(rr->rscblock));
+		pnew->runs[0].rscblock = sc_block_split(rr->rscblock, run_offs);
+		printf("new block 1: '%s'\n", sc_block_contents(rr->rscblock));
+		printf("new block 2: '%s'\n", sc_block_contents(pnew->runs[0].rscblock));
+		printf("run %p block %p\n", &pnew->runs[0], pnew->runs[0].rscblock);
 
 		printf("run %i, para offs %li\n", 0,
 		       (long int)pnew->runs[0].para_offs_bytes);
@@ -1509,7 +1824,7 @@ SCBlock *block_at_cursor(struct frame *fr, int pn, size_t pos)
 
 	if ( para->type != PARA_TYPE_CALLBACK ) return NULL;
 
-	return para->macro_real_scblock;
+	return para->scblock;
 }
 
 
diff --git a/src/frame.h b/src/frame.h
index 6145666..d22cd35 100644
--- a/src/frame.h
+++ b/src/frame.h
@@ -62,7 +62,8 @@ typedef struct _paragraph Paragraph;
 struct edit_pos
 {
 	int para;    /* Paragraph number */
-	size_t pos;  /* Byte position within paragraph */
+	size_t pos;  /* Byte position within paragraph
+	              * Yes, really.  See pango_layout_xy_to_index */
 	int trail;
 };
 
@@ -135,15 +136,13 @@ extern void set_newline_at_end(Paragraph *para, SCBlock *bl);
 extern void check_run(struct frame *fr, int pn);
 extern void show_edit_pos(struct edit_pos a);
 
-extern void add_run(Paragraph *para, SCBlock *scblock,
-                    SCBlock *macro_real, SCBlock *contents_top,
+extern void add_run(Paragraph *para, SCBlock *scblock, SCBlock *rscblock,
                     size_t len_bytes,
-                    PangoFontDescription *fdesc, double col[4],
-                    int macro_editable);
+                    PangoFontDescription *fdesc, double col[4]);
 
 extern Paragraph *insert_paragraph(struct frame *fr, int pos);
 
-extern void add_callback_para(struct frame *fr, SCBlock *scblock, SCBlock *mr,
+extern void add_callback_para(struct frame *fr, SCBlock *scblock,
                               double w, double h,
                               SCCallbackDrawFunc draw_func,
                               SCCallbackClickFunc click_func, void *bvp,
diff --git a/src/sc_editor.c b/src/sc_editor.c
index c872acc..6b8ba69 100644
--- a/src/sc_editor.c
+++ b/src/sc_editor.c
@@ -853,8 +853,8 @@ static void insert_text(char *t, SCEditor *e)
 			fprintf(stderr, "Failed to insert paragraph\n");
 			return;
 		}
-		add_run(pnew, ad, NULL, NULL, strlen(t),
-		        e->cursor_frame->fontdesc, e->cursor_frame->col, 0);
+		add_run(pnew, ad, ad, strlen(t),
+		        e->cursor_frame->fontdesc, e->cursor_frame->col);
 
 		wrap_frame(e->cursor_frame, e->pc);
 
@@ -1076,7 +1076,7 @@ static void check_paragraph(struct frame *fr, PangoContext *pc,
 	}
 	scblocks = sc_block_append(scblocks, NULL, NULL, strdup(""), NULL);
 
-	add_run(para, scblocks, NULL, NULL, 0, fr->fontdesc, fr->col, 0);
+	add_run(para, scblocks, scblocks, 0, fr->fontdesc, fr->col);
 	wrap_paragraph(para, pc, fr->w - fr->pad_l - fr->pad_r, 0, 0);
 }
 
diff --git a/src/sc_interp.c b/src/sc_interp.c
index 24dd4ee..51849d5 100644
--- a/src/sc_interp.c
+++ b/src/sc_interp.c
@@ -239,7 +239,7 @@ static void do_callback(SCInterpreter *scin, SCBlock *bl, const char *name)
 		if ( strcmp(cbl->names[i], name) != 0 ) continue;
 		r = cbl->box_funcs[i](scin, bl, &w, &h, &bvp, cbl->vps[i]);
 		if ( !r ) return;
-		add_callback_para(sc_interp_get_frame(scin), bl, mr, w, h,
+		add_callback_para(sc_interp_get_frame(scin), bl, w, h,
 		                  cbl->draw_funcs[i], cbl->click_funcs[i],
 		                  bvp, cbl->vps[i]);
 
@@ -950,7 +950,7 @@ static int add_text(struct frame *fr, PangoContext *pc, SCBlock *bl,
 	PangoFontDescription *fontdesc;
 	double *col;
 	struct sc_state *st = &scin->state[scin->j];
-	SCBlock *mrb;
+	SCBlock *rbl;
 
 	/* Empty block? */
 	if ( text == NULL ) return 1;
@@ -958,12 +958,16 @@ static int add_text(struct frame *fr, PangoContext *pc, SCBlock *bl,
 
 	fontdesc = sc_interp_get_fontdesc(scin);
 	col = sc_interp_get_fgcol(scin);
-	mrb = sc_interp_get_macro_real_block(scin);
 
 	len_bytes = strlen(text);
 	Paragraph *para = last_open_para(fr);
-	add_run(para, bl, mrb, st->macro_contents, len_bytes,
-	        fontdesc, col, st->macro_editable);
+
+	rbl = bl;
+	if ( st->macro_real_block != NULL ) {
+		bl = st->macro_real_block;
+	}
+
+	add_run(para, bl, rbl, len_bytes, fontdesc, col);
 	set_para_spacing(para, st->paraspace);
 
 	return 0;
@@ -975,6 +979,7 @@ static int check_outputs(SCBlock *bl, SCInterpreter *scin)
 	const char *name = sc_block_name(bl);
 	const char *options = sc_block_options(bl);
 	SCBlock *child = sc_block_child(bl);
+	struct sc_state *st = &scin->state[scin->j];
 
 	if ( name == NULL ) {
 		add_text(sc_interp_get_frame(scin),
@@ -986,7 +991,11 @@ static int check_outputs(SCBlock *bl, SCInterpreter *scin)
 		if ( parse_image_options(options, sc_interp_get_frame(scin),
 		                         &w, &h, &filename) == 0 )
 		{
-			add_image_para(sc_interp_get_frame(scin), bl,
+			SCBlock *ebl = bl;
+			if ( st->macro_real_block != NULL ) {
+				ebl = st->macro_real_block;
+			}
+			add_image_para(sc_interp_get_frame(scin), ebl,
 			               filename, scin->is, w, h, 1);
 			free(filename);
 		} else {
@@ -1022,10 +1031,8 @@ static int check_outputs(SCBlock *bl, SCInterpreter *scin)
 	} else if ( strcmp(name, "newpara")==0 ) {
 		struct frame *fr = sc_interp_get_frame(scin);
 		Paragraph *para = last_open_para(fr);
-		struct sc_state *st = &scin->state[scin->j];
 		/* Add a dummy run which we can type into */
-		add_run(para, bl, st->macro_real_block, st->macro_contents, 0,
-		        sc_interp_get_fontdesc(scin), fr->col, st->macro_editable);
+		add_run(para, bl, bl, 0, sc_interp_get_fontdesc(scin), fr->col);
 		set_newline_at_end(para, bl);
 		close_last_paragraph(fr);
 
diff --git a/src/sc_parse.c b/src/sc_parse.c
index f2814b6..2607031 100644
--- a/src/sc_parse.c
+++ b/src/sc_parse.c
@@ -58,6 +58,7 @@ SCBlock *sc_block_new()
 
 SCBlock *sc_block_next(const SCBlock *bl)
 {
+	assert(bl != NULL);
 	return bl->next;
 }
 
@@ -734,23 +735,27 @@ void sc_insert_block(SCBlock *b1, int o1, SCBlock *ins)
 }
 
 
-void scblock_delete_text(SCBlock *b, size_t o1, size_t o2)
+/* Delete text from SCBlock contents.  o2=-1 means "to the end".
+ * Returns the number of bytes deleted. */
+size_t scblock_delete_text(SCBlock *b, ssize_t o1, ssize_t o2)
 {
-
 	size_t len;
 
 	if ( b->contents == NULL ) {
 		fprintf(stderr, "Deleting text from block \\%s\n", b->name);
-		return;
+		return 0;
 	}
 
 	len = strlen(b->contents);
+	if ( o2 < 0 ) o2 = len;
 	if ( (o1 >= o2) || (o1 > len) || (o2 > len) ) {
 		fprintf(stderr, "Invalid delete: %i %i %i\n",
 		        (int)o1, (int)o2, (int)len);
-		return;
+		return 0;
 	}
 	memmove(b->contents+o1, b->contents+o2, len-o2+1);
+
+	return o2-o1;
 }
 
 
diff --git a/src/sc_parse.h b/src/sc_parse.h
index be7d0ee..ff10638 100644
--- a/src/sc_parse.h
+++ b/src/sc_parse.h
@@ -82,6 +82,6 @@ extern void show_sc_block(const SCBlock *bl, const char *prefix);
 extern char *serialise_sc_block(const SCBlock *bl);
 extern void save_sc_block(FILE *fh, const SCBlock *bl);
 
-extern void scblock_delete_text(SCBlock *b, size_t o1, size_t o2);
+extern size_t scblock_delete_text(SCBlock *b, ssize_t o1, ssize_t o2);
 
 #endif	/* SC_PARSE_H */