/*
 * Copyright 2021 Vincent Sanders <vince@netsurf-browser.org>
 *
 * This file is part of NetSurf, http://www.netsurf-browser.org/
 *
 * NetSurf is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License.
 *
 * NetSurf 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <assert.h>
#include <sys/stat.h>
#include <string.h>
#include <FL/Fl.H>

extern "C" {

#include "utils/utils.h"
#include "utils/log.h"
#include "utils/messages.h"
#include "utils/nsoption.h"
#include "utils/nsurl.h"

#include "netsurf/netsurf.h"
#include "netsurf/content.h"
#include "netsurf/browser_window.h"

}

#include "fltk/misc.h"
#include "fltk/window.h"
#include "fltk/fetch.h"
#include "fltk/bitmap.h"
#include "fltk/layout.h"
#include "fltk/resources.h"

bool nsfltk_done = false;

/**
 * Set option defaults for fltk frontend
 *
 * @param defaults The option table to update.
 * @return error status.
 */
static nserror set_option_defaults(struct nsoption_s *defaults)
{
	return NSERROR_OK;
}


/**
 * Ensures output logging stream is correctly configured
 */
static bool nslog_stream_configure(FILE *fptr)
{
	/* set log stream to be non-buffering */
	setbuf(fptr, NULL);

	return true;
}


/**
 * fltk frontend specific initialisation
 */
static nserror nsfltk_init(int *pargc, char** argv)
{
	nserror res;

	/* Prep the resource search paths */
	res = nsfltk_init_resource_path("${HOME}/.netsurf/:${NETSURFRES}:" FLTK_RESPATH);
	if (res != NSERROR_OK) {
		fprintf(stderr, "Resources failed to initialise (%s)\n",
			messages_get_errorcode(res));
		return res;
	}

	/* Initialise logging. Not fatal if it fails but not much we
	 * can do about it either.
	 */
	nslog_init(nslog_stream_configure, pargc, argv);

	/* override loaded options with those from commandline */
	nsoption_commandline(pargc, argv, nsoptions);

	/* Initialise user options */
	res = nsoption_init(set_option_defaults, &nsoptions, &nsoptions_default);
	if (res != NSERROR_OK) {
		fprintf(stderr, "Options failed to initialise (%s)\n",
			messages_get_errorcode(res));
		return res;
	}

	return NSERROR_OK;
}


/**
 * Start fltk browser.
 *
 * performs fltk specific startup including opening initial window if necessary
 *
 * \param argc The number of arguments on the command line
 * \param argv A string vector of command line arguments.
 */
static nserror nsfltk_start(int argc, char** argv)
{
	char *addr = NULL;
	nsurl *url;
	nserror res;

	/* If there is a url specified on the command line use it */
	if (argc > 1) {
		struct stat fs;
		if (stat(argv[1], &fs) == 0) {
			size_t addrlen;
			char *rp = realpath(argv[1], NULL);
			assert(rp != NULL);

			/* calculate file url length including terminator */
			addrlen = SLEN("file://") + strlen(rp) + 1;
			addr = (char *)malloc(addrlen);
			assert(addr != NULL);
			snprintf(addr, addrlen, "file://%s", rp);
			free(rp);
		} else {
			addr = strdup(argv[1]);
		}
	}
	if (addr != NULL) {
		/* managed to set up based on local launch */
	} else if (nsoption_charp(homepage_url) != NULL) {
		addr = strdup(nsoption_charp(homepage_url));
	} else {
		addr = strdup(NETSURF_HOMEPAGE);
	}

	/* create an initial browser window */
	res = nsurl_create(addr, &url);
	if (res == NSERROR_OK) {
		res = browser_window_create(BW_CREATE_HISTORY,
					    url,
					    NULL,
					    NULL,
					    NULL);
		nsurl_unref(url);
	}

	free(addr);

	return res;
}

/**
 * Run the fltk event loop.
 *
 */
static void nsfltk_run(void)
{
	int schedtm;
	do {
		/* run scheduled callbacks and get the next event delta in ms */
		schedtm = nsfltk_schedule_run();
		Fl::wait(((double)schedtm/1000));
	} while(nsfltk_done != true);
}

static nserror nsfltk_finalise(void)
{
	/* common finalisation */
	netsurf_exit();

	/* finalise options */
	nsoption_finalise(nsoptions, nsoptions_default);

	/* finalise logging */
	nslog_finalise();

	return NSERROR_OK;
}

/**
 * Main entry point from OS.
 */
int main(int argc, char** argv)
{
	nserror res;
	struct netsurf_table nsfltk_table = {
		.misc = nsfltk_misc_table,
		.window = nsfltk_window_table,
		.download = NULL, /* no download functionality */
		.clipboard = NULL, /* no clipboard functionality */
		.fetch = nsfltk_fetch_table,
		.file = NULL, /* use the posix default file operations */
		.utf8 = NULL, /* use default utf-8 processing */
		.search = NULL, /* use the default text search */
		.search_web = NULL, /* use default web search */
		.llcache = NULL, /* use default low level cache storage */
		.bitmap = nsfltk_bitmap_table,
		.layout = nsfltk_layout_table,
	};

	/* register operation tables */
	res = netsurf_register(&nsfltk_table);
	if (res != NSERROR_OK) {
		fprintf(stderr,
			"NetSurf operation table failed registration (%s)\n",
			messages_get_errorcode(res));
		return 1;
	}

	/* fltk specific initialisation */
	res = nsfltk_init(&argc, argv);
	if (res != NSERROR_OK) {
		fprintf(stderr,	"NetSurf fltk initialisation failed (%s)\n",
			messages_get_errorcode(res));
		return 2;
	}

	/* netsurf initialisation */
	res = netsurf_init(NULL);
	if (res != NSERROR_OK) {
		fprintf(stderr,	"NetSurf core failed to initialise (%s)\n",
			messages_get_errorcode(res));
		return 3;
	}

	/* fltk specific startup */
	res = nsfltk_start(argc, argv);
	if (res != NSERROR_OK) {
		fprintf(stderr,	"NetSurf fltk startup failed (%s)\n",
			messages_get_errorcode(res));
		nsfltk_finalise();
		return 4;
	}

	/* startup suceeded so main run loop */
	nsfltk_run();

	/* finalise everything */
	nsfltk_finalise();

	return 0;

}