epub: Implement @font-face rules.

Note: font->fallback is not reference counted here. The fallback
mechanism is probably going to have to change when we add text shaping.

6 files changed, 216 insertions, 19 deletions

diff --git a/include/mupdf/html.h b/include/mupdf/html.h
index 75d46313..48231281 100644
--- a/include/mupdf/html.h
+++ b/include/mupdf/html.h
@@ -3,6 +3,7 @@
 
 #include "mupdf/fitz.h"
 
+typedef struct fz_html_font_face_s fz_html_font_face;
 typedef struct fz_html_font_set_s fz_html_font_set;
 typedef struct fz_html_s fz_html;
 typedef struct fz_html_flow_s fz_html_flow;
@@ -19,10 +20,21 @@ typedef struct fz_css_value_s fz_css_value;
 typedef struct fz_css_number_s fz_css_number;
 typedef struct fz_css_color_s fz_css_color;
 
+struct fz_html_font_face_s
+{
+	char *family;
+	int is_bold;
+	int is_italic;
+	fz_font *font;
+	char *src;
+	fz_html_font_face *next;
+};
+
 struct fz_html_font_set_s
 {
 	fz_font *fonts[16];
 	fz_font *fallback;
+	fz_html_font_face *custom;
 };
 
 enum
@@ -239,11 +251,13 @@ float fz_from_css_number(fz_css_number, float em, float width);
 float fz_from_css_number_scale(fz_css_number number, float scale, float em, float width);
 
 fz_html_font_set *fz_new_html_font_set(fz_context *ctx);
-fz_font *fz_load_html_font(fz_context *ctx, fz_html_font_set *set,
-	const char *family, const char *variant, const char *style, const char *weight);
-fz_font *fz_load_html_fallback_font(fz_context *ctx, fz_html_font_set *set);
+void fz_add_html_font_face(fz_context *ctx, fz_html_font_set *set,
+	const char *family, int is_bold, int is_italic, const char *src, fz_font *font);
+fz_font *fz_load_html_font(fz_context *ctx, fz_html_font_set *set, const char *family, int is_bold, int is_italic);
 void fz_drop_html_font_set(fz_context *ctx, fz_html_font_set *htx);
 
+void fz_add_css_font_faces(fz_context *ctx, fz_html_font_set *set, fz_archive *zip, const char *base_uri, fz_css_rule *css);
+
 fz_html *fz_parse_html(fz_context *ctx, fz_html_font_set *htx, fz_archive *zip, const char *base_uri, fz_buffer *buf, const char *user_css);
 void fz_layout_html(fz_context *ctx, fz_html *box, float w, float h, float em);
 void fz_draw_html(fz_context *ctx, fz_html *box, float page_top, float page_bot, fz_device *dev, const fz_matrix *ctm);
diff --git a/source/fitz/font.c b/source/fitz/font.c
index bdfee584..792e8d95 100644
--- a/source/fitz/font.c
+++ b/source/fitz/font.c
@@ -120,8 +120,6 @@ fz_drop_font(fz_context *ctx, fz_font *font)
 	if (!fz_drop_imp(ctx, font, &font->refs))
 		return;
 
-	fz_drop_font(ctx, font->fallback);
-
 	if (font->t3lists)
 	{
 		free_resources(ctx, font);
diff --git a/source/html/css-apply.c b/source/html/css-apply.c
index 45fa7713..db588bf7 100644
--- a/source/html/css-apply.c
+++ b/source/html/css-apply.c
@@ -106,6 +106,18 @@ keyword_in_list(const char *name, const char **list, int n)
 	return 0;
 }
 
+static int
+is_bold_from_font_weight(const char *weight)
+{
+	return !strcmp(weight, "bold") || !strcmp(weight, "bolder") || atoi(weight) > 400;
+}
+
+static int
+is_italic_from_font_style(const char *style)
+{
+	return !strcmp(style, "italic") || !strcmp(style, "oblique");
+}
+
 /*
  * Compute specificity
  */
@@ -673,6 +685,93 @@ fz_match_css_at_page(fz_context *ctx, fz_css_match *match, fz_css_rule *css)
 	sort_properties(match); /* speed up subsequent value_from_raw_property lookups */
 }
 
+void
+fz_add_css_font_face(fz_context *ctx, fz_html_font_set *set, fz_archive *zip, const char *base_uri, fz_css_property *declaration)
+{
+	fz_html_font_face *custom;
+	fz_css_property *prop;
+	fz_font *font = NULL;
+	fz_buffer *buf = NULL;
+	int is_bold, is_italic;
+	char path[2048];
+
+	const char *family = "serif";
+	const char *weight = "normal";
+	const char *style = "normal";
+	const char *src = NULL;
+
+	for (prop = declaration; prop; prop = prop->next)
+	{
+		if (!strcmp(prop->name, "font-family")) family = prop->value->data;
+		if (!strcmp(prop->name, "font-weight")) weight = prop->value->data;
+		if (!strcmp(prop->name, "font-style")) style = prop->value->data;
+		if (!strcmp(prop->name, "src")) src = prop->value->data;
+	}
+
+	if (!src)
+		return;
+
+	is_bold = is_bold_from_font_weight(weight);
+	is_italic = is_italic_from_font_style(style);
+
+	fz_strlcpy(path, base_uri, sizeof path);
+	fz_strlcat(path, "/", sizeof path);
+	fz_strlcat(path, src, sizeof path);
+	fz_urldecode(path);
+	fz_cleanname(path);
+
+	for (custom = set->custom; custom; custom = custom->next)
+		if (!strcmp(custom->src, path) && !strcmp(custom->family, family) &&
+				custom->is_bold == is_bold &&
+				custom->is_italic == is_italic)
+			return; /* already loaded */
+
+	printf("epub: @font-face: family='%s' b=%d i=%d src=%s\n", family, is_bold, is_italic, src);
+
+	fz_var(buf);
+	fz_var(font);
+
+	fz_try(ctx)
+	{
+		if (fz_has_archive_entry(ctx, zip, path))
+			buf = fz_read_archive_entry(ctx, zip, path);
+		else
+			buf = fz_read_file(ctx, src);
+		font = fz_new_font_from_buffer(ctx, src, buf, 0, 0);
+		fz_add_html_font_face(ctx, set, family, is_bold, is_italic, path, font);
+	}
+	fz_always(ctx)
+	{
+		fz_drop_buffer(ctx, buf);
+		fz_drop_font(ctx, font);
+	}
+	fz_catch(ctx)
+	{
+		fz_warn(ctx, "cannot load font-face: %s", src);
+	}
+}
+
+void
+fz_add_css_font_faces(fz_context *ctx, fz_html_font_set *set, fz_archive *zip, const char *base_uri, fz_css_rule *css)
+{
+	fz_css_rule *rule;
+	fz_css_selector *sel;
+
+	for (rule = css; rule; rule = rule->next)
+	{
+		sel = rule->selector;
+		while (sel)
+		{
+			if (sel->name && !strcmp(sel->name, "@font-face"))
+			{
+				fz_add_css_font_face(ctx, set, zip, base_uri, rule->declaration);
+				break;
+			}
+			sel = sel->next;
+		}
+	}
+}
+
 static fz_css_value *
 value_from_raw_property(fz_css_match *match, const char *name)
 {
@@ -1156,11 +1255,23 @@ fz_apply_css_style(fz_context *ctx, fz_html_font_set *set, fz_css_style *style,
 	style->border_width[3] = border_width_from_property(match, "border-left-width");
 
 	{
-		const char *font_family = string_from_property(match, "font-family", "serif");
-		const char *font_variant = string_from_property(match, "font-variant", "normal");
-		const char *font_style = string_from_property(match, "font-style", "normal");
 		const char *font_weight = string_from_property(match, "font-weight", "normal");
-		style->font = fz_load_html_font(ctx, set, font_family, font_variant, font_style, font_weight);
+		const char *font_style = string_from_property(match, "font-style", "normal");
+		int is_bold = is_bold_from_font_weight(font_weight);
+		int is_italic = is_italic_from_font_style(font_style);
+		value = value_from_property(match, "font-family");
+		while (value)
+		{
+			if (strcmp(value->data, ",") != 0)
+			{
+				style->font = fz_load_html_font(ctx, set, value->data, is_bold, is_italic);
+				if (style->font)
+					break;
+			}
+			value = value->next;
+		}
+		if (!style->font)
+			style->font = fz_load_html_font(ctx, set, "serif", 0, 0);
 	}
 }
 
diff --git a/source/html/css-parse.c b/source/html/css-parse.c
index f9d7595c..e395e933 100644
--- a/source/html/css-parse.c
+++ b/source/html/css-parse.c
@@ -879,6 +879,21 @@ static fz_css_rule *parse_at_page(struct lexbuf *buf)
 	return fz_new_css_rule(buf->ctx, s, p);
 }
 
+static fz_css_rule *parse_at_font_face(struct lexbuf *buf)
+{
+	fz_css_selector *s = NULL;
+	fz_css_property *p = NULL;
+
+	white(buf);
+	expect(buf, '{');
+	p = parse_declaration_list(buf);
+	expect(buf, '}');
+	white(buf);
+
+	s = fz_new_css_selector(buf->ctx, "@font-face");
+	return fz_new_css_rule(buf->ctx, s, p);
+}
+
 static void parse_at_rule(struct lexbuf *buf)
 {
 	expect(buf, CSS_KEYWORD);
@@ -938,6 +953,12 @@ static fz_css_rule *parse_stylesheet(struct lexbuf *buf, fz_css_rule *chain)
 				rule = *nextp = parse_at_page(buf);
 				nextp = &rule->next;
 			}
+			else if (buf->lookahead == CSS_KEYWORD && !strcmp(buf->string, "font-face"))
+			{
+				next(buf);
+				rule = *nextp = parse_at_font_face(buf);
+				nextp = &rule->next;
+			}
 			else
 			{
 				parse_at_rule(buf);
diff --git a/source/html/html-font.c b/source/html/html-font.c
index 4b138162..d595b582 100644
--- a/source/html/html-font.c
+++ b/source/html/html-font.c
@@ -11,7 +11,7 @@ static const char *font_names[16] =
 	"Courier", "Courier-Oblique", "Courier-Bold", "Courier-BoldOblique",
 };
 
-fz_font *
+static fz_font *
 fz_load_html_fallback_font(fz_context *ctx, fz_html_font_set *set)
 {
 	if (!set->fallback)
@@ -29,30 +29,67 @@ fz_load_html_fallback_font(fz_context *ctx, fz_html_font_set *set)
 }
 
 fz_font *
-fz_load_html_font(fz_context *ctx, fz_html_font_set *set,
-	const char *family, const char *variant, const char *style, const char *weight)
+fz_load_html_builtin_font(fz_context *ctx, fz_html_font_set *set, const char *family, int is_bold, int is_italic)
 {
-	unsigned char *data;
-	unsigned int size;
-
 	int is_mono = !strcmp(family, "monospace");
 	int is_sans = !strcmp(family, "sans-serif");
-	int is_bold = !strcmp(weight, "bold") || !strcmp(weight, "bolder") || atoi(weight) > 400;
-	int is_italic = !strcmp(style, "italic") || !strcmp(style, "oblique");
-
 	int idx = is_mono * 8 + is_sans * 4 + is_bold * 2 + is_italic;
 	if (!set->fonts[idx])
 	{
+		unsigned char *data;
+		unsigned int size;
+
 		data = pdf_lookup_builtin_font(ctx, font_names[idx], &size);
 		if (!data)
 			fz_throw(ctx, FZ_ERROR_GENERIC, "cannot load html font: %s", font_names[idx]);
 		set->fonts[idx] = fz_new_font_from_memory(ctx, font_names[idx], data, size, 0, 1);
 		set->fonts[idx]->fallback = fz_load_html_fallback_font(ctx, set);
 	}
-
 	return set->fonts[idx];
 }
 
+fz_font *
+fz_load_html_font(fz_context *ctx, fz_html_font_set *set, const char *family, int is_bold, int is_italic)
+{
+	fz_html_font_face *custom;
+
+	for (custom = set->custom; custom; custom = custom->next)
+	{
+		if (!strcmp(family, custom->family) &&
+				is_bold == custom->is_bold &&
+				is_italic == custom->is_italic)
+		{
+			return custom->font;
+		}
+	}
+
+	if (!strcmp(family, "monospace") ||
+			!strcmp(family, "sans-serif") ||
+			!strcmp(family, "serif"))
+		return fz_load_html_builtin_font(ctx, set, family, is_bold, is_italic);
+
+	return NULL;
+}
+
+void
+fz_add_html_font_face(fz_context *ctx, fz_html_font_set *set,
+	const char *family, int is_bold, int is_italic, const char *src,
+	fz_font *font)
+{
+	fz_html_font_face *custom;
+
+	custom = fz_malloc_struct(ctx, fz_html_font_face);
+	custom->font = fz_keep_font(ctx, font);
+	custom->src = fz_strdup(ctx, src);
+	custom->family = fz_strdup(ctx, family);
+	custom->is_bold = is_bold;
+	custom->is_italic = is_italic;
+	custom->next = set->custom;
+	set->custom = custom;
+
+	font->fallback = fz_load_html_builtin_font(ctx, set, family, is_bold, is_italic);
+}
+
 fz_html_font_set *fz_new_html_font_set(fz_context *ctx)
 {
 	return fz_malloc_struct(ctx, fz_html_font_set);
@@ -60,9 +97,23 @@ fz_html_font_set *fz_new_html_font_set(fz_context *ctx)
 
 void fz_drop_html_font_set(fz_context *ctx, fz_html_font_set *set)
 {
+	fz_html_font_face *font, *next;
 	int i;
+
+	font = set->custom;
+	while (font)
+	{
+		next = font->next;
+		fz_drop_font(ctx, font->font);
+		fz_free(ctx, font->src);
+		fz_free(ctx, font->family);
+		fz_free(ctx, font);
+		font = next;
+	}
+
 	for (i = 0; i < nelem(set->fonts); ++i)
 		fz_drop_font(ctx, set->fonts[i]);
 	fz_drop_font(ctx, set->fallback);
+
 	fz_free(ctx, set);
 }
diff --git a/source/html/html-layout.c b/source/html/html-layout.c
index 42222bdd..24edc567 100644
--- a/source/html/html-layout.c
+++ b/source/html/html-layout.c
@@ -1602,6 +1602,8 @@ fz_parse_html(fz_context *ctx, fz_html_font_set *set, fz_archive *zip, const cha
 
 	// print_rules(css);
 
+	fz_add_css_font_faces(ctx, set, zip, base_uri, css); /* load @font-face fonts into font set */
+
 	pool = fz_new_pool(ctx);
 
 	box = new_box(ctx, pool);