/*
 * Copyright (C) 2022 luca0N!
 *
 * This file is part of Static Website Generator (swg).
 *
 * Static Website Generator (swg) is free software: you can redistribute it
 * and/or modify it under the terms of the version 3 of the GNU Lesser General
 * Public License as published by the Free Software Foundation.
 *
 * Static Website Generator (swg) is distributed in the hope that it will be
 * useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser
 * General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with Static Website Generator (swg). If not, see
 * <https://www.gnu.org/licenses/>.
 *
 * Contact luca0N! by e-mail: <luca0n [at] luca0n [dot] com>. 
 */

#include "Article.hxx"

#include <iostream>
#include <list>
#include <string.h>

#include "Common.hxx"

enum IterationStage {
	CHECKING_TITLE,
	READING_TITLE,
	CHECKING
};

namespace Article {
	/*
	 * FIXME: The article metadata declaration uses the same INI format as
	 * swg.cfg.  Since they use the exact same format, we could unify the .cfg
	 * parsing into one function.
	 */
	void get_metadata(std::string const &path, Metadata *m) {
		memset(m, 0, sizeof(Metadata));
		FILE *a = fopen(path.c_str(), "r");

		int buflen = 16;
		char buf[buflen];

		const char *det_article = "<!--SwgArticle";
		size_t det_article_pos = 0;
		bool reading_metadata = false,
			 done = false,
			 skip = false;

		std::list<std::string> cfg_lines = { "" };

		while (fgets(buf, buflen, a) != NULL) {
			// Ignore blank lines or lines starting with a comment.
			if (buf[0] == '\n' || buf[0] == '#') continue;
			int eol = -1;
			for (int c = 0; c < buflen; c++) {
				// Check if this loop has already done what it's supposed to do by checking if the title has been set.
				if (done || buf[c] == '\0') break;
				if (!reading_metadata) {
				// FIXME: This code will not work if buflen < strlen(det_article).
				if (buf[c] == det_article[det_article_pos]) {
					det_article_pos++;
				} else {
					// TODO: Instead of exiting with an
					// error code, prompt the end user
					// whether the build should continue
					// (while ignoring this article) or
					// stop.
					std::cerr << "error: invalid article: " << path << "\n";
					exit(RETURN_FAILED_UNKNOWN_ERROR);
				}
				if (det_article_pos == strlen(det_article)) {
					reading_metadata = true;
					skip = true;
				}
				}
				// Check end of HTML comment
				if (buf[c] == '-' &&
					buf[c+1] == '-' &&
					buf[c+2] == '>') {
					reading_metadata = false;
					done = true;
					break;
				}
				if (buf[c] == '\n')
					eol = c;
			}
			if (skip) { skip = false; continue; }
			if (done) break;
			if (reading_metadata) {
				if (eol > -1) {
					buf[eol] = '\0';
					*(--cfg_lines.end()) += buf;
					cfg_lines.insert(cfg_lines.end(), "");
				} else
					*(--cfg_lines.end()) += buf;
			}
		}

		bool reading_article_metadata = false;

		for (std::string const &line : cfg_lines) {
				std::cout << "[!] Line: " << line << "\n";
				// Check namespace
				if (reading_article_metadata) {
						std::string k_title = "Title=",
								    k_authors = "Authors=",
									k_published = "Published=";
						if (line.find(k_title) == 0)
								strncpy(m->title, line.substr(k_title.length()).c_str(), sizeof(m->title));
						else if (line.find(k_authors) == 0)
								strncpy(m->authors, line.substr(k_authors.length()).c_str(), sizeof(m->authors));
						else if (line.find(k_published) == 0)
								m->publish_ts = atoi(line.substr(k_published.length()).c_str());
						else
								std::cerr << "warning: ignoring unknown key/value due to unknown key: " << line << std::endl;
				} else if (line[0] == '[') {
						if (line == "[ArticleMetadata]") {
								reading_article_metadata = true;
						} else {
								std::cerr << "error: article properties has unknown namespace: " << line << std::endl;
								exit(RETURN_FAILED_CONFIG_INVALID_SYNTAX);
						}
				}
		}

		fclose(a);
	}
};