/* ui-wiki.c: functions for wiki output
 *
 * Copyright (C) 2006-2017 cgit Development Team <cgit@lists.zx2c4.com>
 * Copyright (C) 2025 Freya Murphy <freya@freyacat.org>
 *
 * Licensed under GNU General Public License v2
 *   (see COPYING for full license text)
 */

 #define USE_THE_REPOSITORY_VARIABLE

#include "cgit.h"
#include "ui-wiki.h"
#include "html.h"
#include "ui-shared.h"

 #define WIKI_PATH ".wiki"

struct walk_wiki_context {
	char *curr_rev;
	int state;
	int index;
};

static void print_page(const struct object_id *oid, const char *path, const char *basename, const char *rev)
{
	enum object_type type;
	unsigned long size;
	char *buf;

	type = odb_read_object_info(the_repository->objects, oid, &size);
	if (type == OBJ_BAD) {
		cgit_print_error_page(404, "Not found",
			"Bad object name: %s", oid_to_hex(oid));
		return;
	}

	buf = odb_read_object(the_repository->objects, oid, &type, &size);
	if (!buf) {
		cgit_print_error_page(500, "Internal server error",
			"Error reading object %s", oid_to_hex(oid));
		return;
	}

	html("<div id='summary'>");
	cgit_open_filter(ctx.repo->about_filter, basename);
	html_raw(buf, size);
	cgit_close_filter(ctx.repo->about_filter);
	html("</div>");

	free(buf);
}

static int ls_wiki(const struct object_id *oid, const char *pathname, struct walk_wiki_context *walk_wiki_ctx)
{
	char *name, *link, *ptr;

	if (isdigit(*pathname)) {
		long index = strtol(pathname, &ptr, 10);
		if (ptr && *ptr == '-') {
			pathname = ptr + 1;
			walk_wiki_ctx->index = index;
		}
	}

	name = xstrdup(pathname);
	ptr = strrchr(name, '.');
	if (ptr)
		*ptr = '\0';
	link = xstrdup(name);
	for (ptr = name; *ptr; ptr++) {
		if (*ptr == '-')
			*ptr = ' ';
	}
	for (ptr = link; *ptr; ptr++)
		*ptr = tolower(*ptr);

	html("<tr><td class='ls-index'>");
	htmlf("%d", walk_wiki_ctx->index);
	html("</td><td class>");
	cgit_wiki_link(name, NULL, "ls-link", ctx.qry.head, walk_wiki_ctx->curr_rev, link);
	html("</td></tr>\n");

	walk_wiki_ctx->index++;
	free(name);
	free(link);
	return 0;
}

static void ls_head(void)
{
	cgit_print_layout_start();
	html("<table summary='wiki listing' class='list'>\n");
	html("<tr class='nohover'>");
	html("<th class='left'>Index</th>");
	html("<th class='left'>Title</th>");
	html("<th/>");
	html("</tr>\n");
}

static void ls_tail(void)
{
	html("</table>\n");
}

static int walk_wiki(const struct object_id *oid, struct strbuf *base,
		const char *pathname, unsigned mode, void *cbdata)
{
	struct walk_wiki_context *walk_wiki_ctx = cbdata;

	if (!strcmp(pathname, WIKI_PATH))
		return READ_TREE_RECURSIVE;

	if (walk_wiki_ctx->state < 2) {
		if (walk_wiki_ctx->state == 0) {
			walk_wiki_ctx->state = 1;
			ls_head();
		}

		ls_wiki(oid, pathname, walk_wiki_ctx);
	} else if (walk_wiki_ctx->state == 2) {
		const char *name;

		name = pathname;
		if (isdigit(*name)) {
			char *ptr;
			strtol(name, &ptr, 10);
			if (ptr && *ptr == '-')
				name = ptr + 1;
		}

		if (!strncasecmp(name, ctx.qry.path, strlen(ctx.qry.path))) {
			struct strbuf buffer = STRBUF_INIT;

			strbuf_addbuf(&buffer, base);
			strbuf_addstr(&buffer, pathname);

			walk_wiki_ctx->state = 3;
			print_page(oid, pathname, buffer.buf, walk_wiki_ctx->curr_rev);
			strbuf_release(&buffer);
		}
	}

	return 0;
}

/*
 * Show repo wiki
 *   rev:  the commit pointing at the root ui object
 *   path: partial name of a wiki md file
 */
void cgit_print_wiki(const char *rev)
{
	struct object_id oid;
	struct commit *commit;
	struct pathspec_item path_items = {
		.match = WIKI_PATH,
		.len = sizeof(WIKI_PATH) - 1,
	};
	struct pathspec paths = {
		.nr = 1,
		.items = &path_items
	};
	struct walk_wiki_context walk_wiki_ctx = {
		.state = 0,
		.index = 1
	};

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

	if (repo_get_oid(the_repository, rev, &oid)) {
		cgit_print_error_page(404, "Not found",
			"Invalid revision name: %s", rev);
		return;
	}
	commit = lookup_commit_reference(the_repository, &oid);
	if (!commit || repo_parse_commit(the_repository, commit)) {
		cgit_print_error_page(404, "Not found",
			"Invalid commit reference: %s", rev);
		return;
	}

	walk_wiki_ctx.curr_rev = xstrdup(rev);

	// print wiki pages
	read_tree(the_repository, repo_get_commit_tree(the_repository, commit),
		  &paths, walk_wiki, &walk_wiki_ctx);

	if (walk_wiki_ctx.state == 0) {
		cgit_print_error_page(404, "Not found", "Wiki not found");
		goto cleanup;
	}

	ls_tail();

	// print active wiki page
	if (ctx.qry.path) {
		html("<hr>\n");

		walk_wiki_ctx.state = 2;
		read_tree(the_repository, repo_get_commit_tree(the_repository, commit),
			  &paths, walk_wiki, &walk_wiki_ctx);

		if (walk_wiki_ctx.state == 2)
			cgit_print_error("Wiki page not found");
	}

	cgit_print_layout_end();

cleanup:
	free(walk_wiki_ctx.curr_rev);
}