/*
 * 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 "ConfigUtils.hxx"

#include <iostream>
#include <cstring>
#include <cassert>

#include "Common.hxx"

void parse_config(SwgContext *ctx, std::string const &path) {
	std::string ctxCfgPath = path;
	ctxCfgPath += "/swg.cfg";

	FILE *ctxCfgFile = fopen(ctxCfgPath.c_str(), "r");

	if (ctxCfgFile == NULL) {
		std::cerr << "error: cannot open swg.cfg file, are you sure "
			<< path << " is a valid SWG directory?" << std::endl;
		perror(ctxCfgPath.c_str());
		exit(RETURN_FAILED_INVALID_DIRECTORY);
	}

	int buflen = 16;
	char cbuf[buflen];

	// Yes, this looks ugly, but it works for now. Will probably optimize
	// this in the future :)
	//
	// TODO: Optimize config file interpretation

	std::list<std::string> lines = { "" };
	while (fgets(cbuf, buflen, ctxCfgFile) != NULL) {
		int eol = -1;
		for (int c = 0; c < buflen; c++) {
			if (cbuf[c] == '\0') {
				break;
			} else if (cbuf[c] == '\n') {
				eol = c;
				break;
			}
		}
		if (eol > -1) {
			cbuf[eol] = '\0';
			*(--lines.end()) += cbuf;
			lines.insert(lines.end(), "");
		} else
			*(--lines.end()) += cbuf;
	}

	fclose(ctxCfgFile);

	std::cout << "Done loading configuration file in memory" << std::endl;

	// Parse configuration file
	
	enum ConfigNamespace { General, Blogs };
	ConfigNamespace ns;

	int blogCount = 0;
	Blog *currentBlog = NULL; // (Blog*) malloc(sizeof(Blog));

	// currentBlog->name = "asd";

	for (std::string line : lines) {
		// Skip comment lines
		if (line.c_str()[0] == '#')
			continue;

		if (line.c_str()[0] == '[') {
			if (line == "[General]") {
				ns = General;
				continue;
			} else if (line == "[Blogs]") {
				ns = Blogs;
				continue;
			} else {
				std::cerr << "error: unknown namespace in config file: " << line << std::endl;
				exit(RETURN_FAILED_CONFIG_INVALID_SYNTAX);
			}
		}

		// Skip empty lines
		if (line == "") continue;

		int end = line.find("=");
		std::string k = line.substr(0, end),
			v = line.substr(end + 2,
					(line.length() - 1) - (end + 2));

		switch (ns) {
			case General:
				if (k == "WebsiteName")
					ctx->websiteName = v;
				else if (k == "WebsitePublisher")
					ctx->websitePublisher = v;
				else if (k == "WebsiteCopyrightHolder")
					ctx->websiteCopyrightHolder = v;
				else if (k == "WebsiteCopyrightYears")
					ctx->websiteCopyrightYears = v;
				else if (k == "websiteContentLicense")
					ctx->websiteContentLicense = v;
				else 
					std::cerr << "warning: unknown key in namespace \"General\": " << k << std::endl;
				continue;
			case Blogs:
					// FIXME: This code only accepts up to 9 blogs.
					if (line.substr(0, 4) == "Blog") {
						// Check No.
						int blogNo = atoi(line.substr(4, 1).c_str());
						if (blogNo != blogCount &&
							blogNo != blogCount +1){
							std::cerr << "error: blog declaration must be incremental (received "
								<< blogNo << " instead of " << blogCount << " or " << blogCount + 1
								<< ")" << std::endl;
							exit(RETURN_FAILED_CONFIG_INVALID_SYNTAX);
						} else if (blogNo == blogCount + 1) {
							blogCount++;
							if (currentBlog != NULL) ctx->blogs.push_back(currentBlog);
							currentBlog = (Blog*) malloc(sizeof(Blog));
							// Clear allocated memory
							memset(currentBlog, 0, sizeof(Blog));
						}

						assert(currentBlog != NULL);
						//std::cout << "Attempting to set K/V" << std::endl;

						if (k.substr(5) == "Path") {
							//std::cout << "Setting path (" << v << ") for " << blogCount << std::endl;
							strncpy(currentBlog->path, v.c_str(), sizeof(currentBlog->path));
						} else if (k.substr(5) == "Name") {
							//std::cout << "Setting name (" << v <<  ") for " << blogCount << std::endl;
							strncpy(currentBlog->name, v.c_str(), sizeof(currentBlog->name));
						} else if (k.substr(5) == "Dir") {
							strncpy(currentBlog->dir, v.c_str(), sizeof(currentBlog->dir));
						} else {
							std::cerr << "warning: unknown key in namespace \"Blogs\": " << k << "\n";
						}
					}
				continue;
		}
	}
	if (currentBlog != NULL) ctx->blogs.push_back(currentBlog);
	/*std::cout << "Loaded " << blogCount << " blogs into memory" << std::endl;
	for (Blog *b : ctx->blogs) {
		std::cout << "\t" << b->name << ": " << b->path << std::endl;
	}*/
}