[PATCH 2/3] ui-repolist: Restructure internal logic to be more extensible

[tim.nordell at logicpd.com (Tim Nordell)]

The internal logic has been restructured so that there is a "walking"
routine that filters the repo list based on the visible criteria, and
subsequently calls a given callback for each repo found.  Additionally,
split out generating a table line for a given repo, and a table line
for a given section.  This makes this more loosely coupled and allows
reuse of more logic for changes to the way the repo list is displayed.
This patch does not make any functional changes to the system and is
a reorganization of the existing logic only.

Signed-off-by: Tim Nordell <tim.nordell at logicpd.com>

diff --git a/ui-repolist.c b/ui-repolist.c
index 7af77e0..6b06a1a 100644
--- a/ui-repolist.c
+++ b/ui-repolist.c
@@ -269,13 +269,135 @@ static int sort_repolist(char *field)
 	return 0;
 }
 
+struct repolist_ctx
+{
+	/* From outer contex passed to interior */
+	int columns;
+	int sorted;
+
+	/* Used in interior context; should be reset in repolist_walk_visible() */
+	int hits;
+	const char *last_section;
+};
+
+static void html_section(struct cgit_repo *repo, int columns)
+{
+	htmlf("<tr class='nohover'><td colspan='%d' class='reposection'>",
+		columns);
+	if (ctx.cfg.section_filter)
+		cgit_open_filter(ctx.cfg.section_filter);
+	html_txt(repo->section);
+	if (ctx.cfg.section_filter)
+		cgit_close_filter(ctx.cfg.section_filter);
+	html("</td></tr>");
+}
+
+static void html_repository(struct cgit_repo *repo, int sorted)
+{
+	bool is_toplevel;
+
+	ctx.repo = repo;
+
+	is_toplevel = (!sorted && NULL != repo->section && repo->section[0] != '\0');
+	htmlf("<tr><td class='%s'>", is_toplevel ? "sublevel-repo" : "toplevel-repo");
+	cgit_summary_link(repo->name, repo->name, NULL, NULL);
+	html("</td><td>");
+	html_link_open(cgit_repourl(repo->url), NULL, NULL);
+	html_ntxt(ctx.cfg.max_repodesc_len, repo->desc);
+	html_link_close();
+	html("</td><td>");
+	if (ctx.cfg.enable_index_owner) {
+		if (repo->owner_filter) {
+			cgit_open_filter(repo->owner_filter);
+			html_txt(repo->owner);
+			cgit_close_filter(repo->owner_filter);
+		} else {
+			html("<a href='");
+			html_attr(cgit_currenturl());
+			html("?q=");
+			html_url_arg(repo->owner);
+			html("'>");
+			html_txt(repo->owner);
+			html("</a>");
+		}
+		html("</td><td>");
+	}
+	print_modtime(repo);
+	html("</td>");
+	if (ctx.cfg.enable_index_links) {
+		html("<td>");
+		cgit_summary_link("summary", NULL, "button", NULL);
+		cgit_log_link("log", NULL, "button", NULL, NULL, NULL,
+				0, NULL, NULL, ctx.qry.showmsg, 0);
+		cgit_tree_link("tree", NULL, "button", NULL, NULL, NULL);
+		html("</td>");
+	}
+	html("</tr>\n");
+}
+
+static inline bool should_emit_section(struct cgit_repo *repo, struct repolist_ctx *c)
+{
+	/* If we're sorted, we will not have a new section emitted. */
+	if (c->sorted)
+		return false;
+
+	/* We need a valid repo section for the rest of the checks */
+	if(NULL == repo->section)
+		return false;
+
+	/* If the section title is blank (e.g. top-level), we never emit
+	 * a section heading. */
+	if('\0' == repo->section[0])
+		return false;
+
+	/* Finally, compare the last section name to the current.  If they're
+	 * the same, do not emit a section area. */
+	if(NULL != c->last_section && !strcmp(repo->section, c->last_section))
+		return false;
+
+	c->last_section = repo->section;
+	return true;
+}
+
+static int generate_repolist(struct cgit_repo *repo, struct repolist_ctx *c)
+{
+	c->hits++;
+	if (c->hits <= ctx.qry.ofs)
+		return 0;
+	if (c->hits > ctx.qry.ofs + ctx.cfg.max_repo_count)
+		return 0;
+
+	if(should_emit_section(repo, c))
+		html_section(repo, c->columns);
+	html_repository(repo, c->sorted);
+
+	return 0;
+}
+
+typedef int (*repolist_walk_callback_t)(struct cgit_repo *repo, struct repolist_ctx *c);
+static int repolist_walk_visible(repolist_walk_callback_t callback, struct repolist_ctx *c)
+{
+	struct cgit_repo *repo;
+	int i;
+
+	c->hits = 0;
+	c->last_section = NULL;
+
+	for (i = 0; i < cgit_repolist.count; i++) {
+		repo = &cgit_repolist.repos[i];
+		if (!is_visible(repo))
+			continue;
+		if(NULL != callback)
+			callback(repo, c);
+	}
+	return 0;
+}
 
 void cgit_print_repolist(void)
 {
-	int i, columns = 3, hits = 0, header = 0;
-	char *last_section = NULL;
-	char *section;
-	int sorted = 0;
+	struct repolist_ctx repolist_ctx = {0};
+
+	repolist_ctx.columns = 3;
 
 	if (!any_repos_visible()) {
 		cgit_print_error_page(404, "Not found", "No repositories found");
@@ -283,9 +405,9 @@ void cgit_print_repolist(void)
 	}
 
 	if (ctx.cfg.enable_index_links)
-		++columns;
+		++repolist_ctx.columns;
 	if (ctx.cfg.enable_index_owner)
-		++columns;
+		++repolist_ctx.columns;
 
 	ctx.page.title = ctx.cfg.root_title;
 	cgit_print_http_headers();
@@ -296,79 +418,19 @@ void cgit_print_repolist(void)
 		html_include(ctx.cfg.index_header);
 
 	if (ctx.qry.sort)
-		sorted = sort_repolist(ctx.qry.sort);
+		repolist_ctx.sorted = sort_repolist(ctx.qry.sort);
 	else if (ctx.cfg.section_sort)
 		sort_repolist("section");
 
 	html("<table summary='repository list' class='list nowrap'>");
-	for (i = 0; i < cgit_repolist.count; i++) {
-		ctx.repo = &cgit_repolist.repos[i];
-		if (!is_visible(ctx.repo))
-			continue;
-		hits++;
-		if (hits <= ctx.qry.ofs)
-			continue;
-		if (hits > ctx.qry.ofs + ctx.cfg.max_repo_count)
-			continue;
-		if (!header++)
-			print_header();
-		section = ctx.repo->section;
-		if (section && !strcmp(section, ""))
-			section = NULL;
-		if (!sorted &&
-		    ((last_section == NULL && section != NULL) ||
-		    (last_section != NULL && section == NULL) ||
-		    (last_section != NULL && section != NULL &&
-		     strcmp(section, last_section)))) {
-			htmlf("<tr class='nohover'><td colspan='%d' class='reposection'>",
-			      columns);
-			if (ctx.cfg.section_filter)
-				cgit_open_filter(ctx.cfg.section_filter);
-			html_txt(section);
-			if (ctx.cfg.section_filter)
-				cgit_close_filter(ctx.cfg.section_filter);
-			html("</td></tr>");
-			last_section = section;
-		}
-		htmlf("<tr><td class='%s'>",
-		      !sorted && section ? "sublevel-repo" : "toplevel-repo");
-		cgit_summary_link(ctx.repo->name, ctx.repo->name, NULL, NULL);
-		html("</td><td>");
-		html_link_open(cgit_repourl(ctx.repo->url), NULL, NULL);
-		html_ntxt(ctx.cfg.max_repodesc_len, ctx.repo->desc);
-		html_link_close();
-		html("</td><td>");
-		if (ctx.cfg.enable_index_owner) {
-			if (ctx.repo->owner_filter) {
-				cgit_open_filter(ctx.repo->owner_filter);
-				html_txt(ctx.repo->owner);
-				cgit_close_filter(ctx.repo->owner_filter);
-			} else {
-				html("<a href='");
-				html_attr(cgit_currenturl());
-				html("?q=");
-				html_url_arg(ctx.repo->owner);
-				html("'>");
-				html_txt(ctx.repo->owner);
-				html("</a>");
-			}
-			html("</td><td>");
-		}
-		print_modtime(ctx.repo);
-		html("</td>");
-		if (ctx.cfg.enable_index_links) {
-			html("<td>");
-			cgit_summary_link("summary", NULL, "button", NULL);
-			cgit_log_link("log", NULL, "button", NULL, NULL, NULL,
-				      0, NULL, NULL, ctx.qry.showmsg, 0);
-			cgit_tree_link("tree", NULL, "button", NULL, NULL, NULL);
-			html("</td>");
-		}
-		html("</tr>\n");
-	}
+	print_header();
+
+	/* Count visible repositories */
+	repolist_walk_visible(generate_repolist, &repolist_ctx);
+
 	html("</table>");
-	if (hits > ctx.cfg.max_repo_count)
-		print_pager(hits, ctx.cfg.max_repo_count, ctx.qry.search, ctx.qry.sort);
+	if (repolist_ctx.hits > ctx.cfg.max_repo_count)
+		print_pager(repolist_ctx.hits, ctx.cfg.max_repo_count, ctx.qry.search, ctx.qry.sort);
 	cgit_print_docend();
 }
 
-- 
2.4.9