/*
 * Module for main() function and some initializations.
 *
 * Copyright INOUE Seiichiro <inoue@ainet.or.jp>, licensed under the GPL.
 */
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <signal.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <gnome.h>
#include "diff.h"
#include "misc.h"
#include "gui.h"
#include "gdwin.h"
#include "dirview.h"
#include "onepaneview.h"
#include "multipaneview.h"
#include "mergeview.h"
#include "properties.h"
#include "style.h"


/* Private function declarations */
static void gtkdiff_init(void);
static void argument_init(GDiffWindow *gdwin, char **arg_files);
#if !defined(DEBUG) || defined(MSG_DIALOG)
static void msg_handler(const gchar *log_domain, GLogLevelFlags log_level, const gchar *message, gpointer user_data);
#endif
static void signal_child(int sig);

static char *merge_outfile = NULL;

int
main(int argc, char *argv[])
{
	GDiffWindow *gdwin;
	char **arg_files;
	static char *geometry_string = NULL;
	poptContext ctx;
	static const struct poptOption options[] = {
		{"geometry", 'g', POPT_ARG_STRING, &geometry_string, 0,
		 N_("Specify geometry"), N_("GEOMETRY")},
		{"output", 'o', POPT_ARG_STRING, &merge_outfile, 0,
		 N_("Merge output filename"), N_("FILENAME")},
		{NULL, '\0', 0, NULL, 0, NULL, NULL}
	};
	
	/* Initialize the i18n stuff */
	bindtextdomain(PACKAGE, GNOMELOCALEDIR);
	textdomain(PACKAGE);

	/*
	 * gnome_init() is always called at the beginning of a program.  it
	 * takes care of initializing both Gtk and GNOME.  It also parses
	 * the command-line arguments.
	 */
	gnome_init_with_popt_table(APPNAME, VERSION, argc, argv,
							   options, 0, &ctx);

#if !defined(DEBUG) || defined(MSG_DIALOG)
	g_log_set_handler(G_LOG_DOMAIN, G_LOG_LEVEL_MESSAGE, msg_handler, NULL);
#endif
	style_init();
	gtkdiff_init();
	properties_init();

	/* Create window */
	gdwin = gdwin_new(geometry_string);

	arg_files = poptGetArgs(ctx);
	argument_init(gdwin, arg_files);
	poptFreeContext(ctx);
	
	gtk_main();

	/* after gtk_main_quit() */
	properties_exit();

	return 0;
}


/* ---The followings are private functions--- */
/**
 * gtkdiff_init:
 * In the future, it will do more.
 **/
static void
gtkdiff_init(void)
{
#ifdef HAVE_SIGACTION
	struct sigaction sa;
	
	memset(&sa, 0, sizeof(sa));
	sa.sa_handler = signal_child;
	sa.sa_flags = SA_RESTART;
	if (sigaction(SIGCHLD, &sa, NULL) == -1) {
		gtk_exit(1);
	}
#else
	signal(SIGCHLD, signal_child);
#endif
}


/**
 * argument_init:
 * Take care of the files specified by command line option.
 **/
static void
argument_init(GDiffWindow *gdwin, char **arg_files)
{
	const char *fname[MAX_NUM_COMPARE_FILES];
	FileType ftype[MAX_NUM_COMPARE_FILES];
	GtkWidget *new_view = NULL;
	DiffDir *diffdir;
	int n;
	gboolean is_diff3 = FALSE;

	if (arg_files && arg_files[0] && arg_files[1]) {
		fname[FIRST_FILE] = arg_files[0];
		fname[SECOND_FILE] = arg_files[1];
		if (arg_files[2]) {
			fname[THIRD_FILE] = arg_files[2];
			is_diff3 = TRUE;
		}
	} else
		return;

	for (n = 0; n < (is_diff3 ? 3 : 2); n++) {
		ftype[n] = check_filetype(fname[n]);
	}

	if (ftype[0] != ftype[1]
		|| (ftype[0] != DIRECTORY && ftype[0] != REGULARFILE)) {
		g_message(_("you can't compare %1$s and %2$s.\n"), fname[0], fname[1]);
		return;
	}
	if (is_diff3) {
		if (ftype[1] != ftype[2]) {
			g_message(_("you can't compare %1$s, %2$s and %3$s.\n"), fname[0], fname[1], fname[2]);
			return;
		}
	}

	/* Now, directory diff3 isn't supported */
	if (is_diff3 && ftype[0] == DIRECTORY) {
		g_message("Currently, directory diff3 is not supported.");/* No need to translate */
		return;
	}

	if (is_diff3)
		diffdir = diffdir_new(fname[FIRST_FILE], fname[SECOND_FILE],
							  fname[THIRD_FILE], g_pref.diff3_args);
	else
		diffdir = diffdir_new(fname[FIRST_FILE], fname[SECOND_FILE],
							  NULL, g_pref.diff_args);

	if (merge_outfile)
		g_pref.fvpref.view_type = MERGE_MASK_VIEW;
	
	if (ftype[0] == DIRECTORY) {
		new_view = gdiff_dirview_new(diffdir);
	} else if (ftype[0] == REGULARFILE) {
		DiffFiles *dfiles = g_slist_nth_data(diffdir->dfiles_list, 0);
		if (g_pref.fvpref.view_type & ONEPANE_MASK_VIEW)
			new_view = gdiff_onepview_new(diffdir, dfiles, FALSE);
		else if (g_pref.fvpref.view_type & MULTIPANE_MASK_VIEW)
			new_view = gdiff_multipview_new(diffdir, dfiles, FALSE);
		else if (g_pref.fvpref.view_type & MERGE_MASK_VIEW) {
			new_view = gdiff_mergeview_new(diffdir, dfiles, FALSE);
			if (merge_outfile)
				gdiff_mergeview_set_outfile(GDIFF_MERGEVIEW(new_view), merge_outfile);
		} else
			return;
	} else
		g_assert_not_reached();

	gdwin_add_view(gdwin, new_view);
}


#if !defined(DEBUG) || defined(MSG_DIALOG)
/**
 * msg_handler:
 * Handler for g_message(). Show a modal dialog box.
 **/
static void
msg_handler(const gchar *log_domain, GLogLevelFlags log_level, const gchar *message, gpointer user_data)
{
	GtkWidget *dialog;

	dialog = gnome_message_box_new(message, GNOME_MESSAGE_BOX_WARNING, GNOME_STOCK_BUTTON_OK, NULL);
	/* I can't use this, because it internally calls gtk_widget_show(),
	   so set_position doesn't work.
	   dialog = gnome_warning_dialog(message); */
	gtk_window_set_modal(GTK_WINDOW(dialog), TRUE);
	gtk_window_set_position(GTK_WINDOW(dialog), GTK_WIN_POS_MOUSE);
	gtk_widget_show(dialog);
}
#endif


/**
 * signal_child:
 * (Unix)signal handler.
 * It takes care of child process death.
 **/
static void
signal_child(int sig)
{
	int stat;

	if (sig == SIGCHLD) {
#ifdef HAVE_WAITPID
		while (waitpid(-1, &stat, WNOHANG) > 0)
			;
#else
		wait(&stat);
#endif
	}
}