/*
 * The tag page, which shows a single ref under refs/tags and is where the
 * branch and tag listings link. An annotated tag is a git object in its own
 * right, so its page carries the tagger, the date and the message, while a
 * lightweight tag is only a name for a commit and gets a shorter table. Both
 * forms link the object the tag points at and, when the repository enables
 * snapshots, offer the tree at that tag for download as an archive.
 */

#define USE_THE_REPOSITORY_VARIABLE

#include "cgit.h"
#include "filter.h"
#include "html.h"
#include "parsing.h"
#include "shared.h"
#include "ui-shared.h"
#include "ui-tag.h"

// The rows share the commit page's three column layout, so a single value
// spans the name and date columns of the tagger row.
static void print_tag_row(const char *revname, const struct object_id *oid)
{
	html("<tr><th>tag</th><td colspan='2'>");
	html_txt(revname);
	if (oid)
		htmlf(" (<span class='oid'>%s</span>)", oid_to_hex(oid));
	html("</td></tr>\n");
}

static void print_object_row(struct object *obj)
{
	html("<tr><th>object</th><td colspan='2' class='oid'>");
	cgit_object_link(obj);
	html("</td></tr>\n");
}

static void print_download_row(const char *revname)
{
	html("<tr><th>download</th><td colspan='2' class='oid'>");
	cgit_print_snapshot_links(ctx.repo, revname, "<br>");
	html("</td></tr>\n");
}

static void print_tagger_row(struct taginfo *info)
{
	html("<tr><th>tagger</th><td>");
	// A tag can carry a tagger with no address, and a filter must not be
	// handed a NULL argument.
	cgit_open_filter(ctx.repo->email_filter, info->tagger_email ? info->tagger_email : "", "tag");
	html_txt(info->tagger);
	if (info->tagger_email && ctx.cfg.enable_plain_email) {
		html(" ");
		html_txt(info->tagger_email);
	}
	cgit_close_filter(ctx.repo->email_filter);
	html("</td><td class='right'>");
	if (info->tagger_date > 0) {
		html("<time datetime='");
		html_attr(show_date(info->tagger_date, info->tagger_tz, cgit_date_mode(DATE_ISO8601_STRICT)));
		html("'>");
		html_txt(show_date(info->tagger_date, info->tagger_tz, cgit_date_mode(DATE_ISO8601)));
		html("</time>");
	}
	html("</td></tr>\n");
}

/*
 * Cutting the subject out terminates the message in place, which is safe only
 * because the caller frees it straight after. The blank lines between the
 * subject and the body are skipped, as the commit page skips them.
 */
static void print_message(char *msg)
{
	char *newline, *body;

	if (!msg)
		return;

	html("<div class='commit-subject'>");
	newline = strchr(msg, '\n');
	if (newline)
		*newline = '\0';
	html_txt(msg);
	html("</div>");
	if (newline) {
		body = newline + 1;
		while (*body == '\n')
			body++;
		html("<div class='commit-msg'>");
		html_txt(body);
		html("</div>");
	}
}

static void print_annotated_tag(const char *revname, const struct object_id *oid)
{
	struct tag *tag;
	struct taginfo *info;

	tag = lookup_tag(the_repository, oid);
	if (!tag || parse_tag(the_repository, tag) || !(info = cgit_parse_tag(tag))) {
		cgit_print_error_page(500, "Internal Server Error", "Bad tag object: %s", revname);
		return;
	}

	cgit_print_layout_start();
	html("<table class='commit-info'>\n");
	if (info->tagger)
		print_tagger_row(info);
	print_tag_row(revname, oid);
	print_object_row(tag->tagged);
	if (ctx.repo->snapshots)
		print_download_row(revname);
	html("</table>\n");
	print_message(info->msg);
	cgit_print_layout_end();
	cgit_free_taginfo(info);
}

static void print_lightweight_tag(const char *revname, struct object *obj)
{
	cgit_print_layout_start();
	html("<table class='commit-info'>\n");
	print_tag_row(revname, NULL);
	print_object_row(obj);
	if (ctx.repo->snapshots)
		print_download_row(revname);
	html("</table>\n");
	cgit_print_layout_end();
}

void cgit_print_tag(char *revname)
{
	struct strbuf fullref = STRBUF_INIT;
	struct object_id oid;
	struct object *obj;

	if (!revname)
		revname = ctx.qry.head;

	strbuf_addf(&fullref, "refs/tags/%s", revname);
	if (repo_get_oid(the_repository, fullref.buf, &oid)) {
		cgit_print_error_page(404, "Not Found", "Bad tag reference: %s", revname);
		goto cleanup;
	}
	obj = parse_object(the_repository, &oid);
	if (!obj) {
		cgit_print_error_page(500, "Internal Server Error", "Bad object id: %s", oid_to_hex(&oid));
		goto cleanup;
	}
	if (obj->type == OBJ_TAG)
		print_annotated_tag(revname, &oid);
	else
		print_lightweight_tag(revname, obj);

cleanup:
	strbuf_release(&fullref);
}