/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
 *
 * Copyright (C) 2007-2008 Richard Hughes <richard@hughsie.com>
 *
 * Licensed under the GNU General Public License Version 2
 *
 * This program 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; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

/**
 * SECTION:egg-debug
 * @short_description: Debugging functions
 *
 * This file contains functions that can be used for debugging.
 */

#include <glib.h>
#include <glib/gi18n.h>
#include <glib/gprintf.h>
#include <stdio.h>
#include <string.h>
#include <stdarg.h>
#include <stdlib.h>
#include <signal.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <time.h>
#include <execinfo.h>

#include "egg-debug.h"

#define CONSOLE_RESET		0
#define CONSOLE_BLACK 		30
#define CONSOLE_RED		31
#define CONSOLE_GREEN		32
#define CONSOLE_YELLOW		33
#define CONSOLE_BLUE		34
#define CONSOLE_MAGENTA		35
#define CONSOLE_CYAN		36
#define CONSOLE_WHITE		37

static gint fd = -1;

/**
 * pk_set_console_mode:
 **/
static void
pk_set_console_mode (guint console_code)
{
	gchar command[13];

	/* don't put extra commands into logs */
	if (!egg_debug_is_console ())
		return;

	/* Command is the control command to the terminal */
	g_snprintf (command, 13, "%c[%dm", 0x1B, console_code);
	printf ("%s", command);
}

/**
 * egg_debug_backtrace:
 **/
void
egg_debug_backtrace (void)
{
	void *call_stack[512];
	int  call_stack_size;
	char **symbols;
	int i = 1;

	call_stack_size = backtrace (call_stack, G_N_ELEMENTS (call_stack));
	symbols = backtrace_symbols (call_stack, call_stack_size);
	if (symbols != NULL) {
		pk_set_console_mode (CONSOLE_RED);
		g_print ("Traceback:\n");
		while (i < call_stack_size) {
			g_print ("\t%s\n", symbols[i]);
			i++;
		}
		pk_set_console_mode (CONSOLE_RESET);
		free (symbols);
	}
}

/**
 * pk_log_line:
 **/
static void
pk_log_line (const gchar *buffer)
{
	ssize_t count;
	/* open a file */
	if (fd == -1) {
		/* ITS4: ignore, /var/log/foo is owned by root, and this is just debug text */
		fd = open (EGG_LOG_FILE, O_WRONLY|O_APPEND|O_CREAT, 0777);
		if (fd == -1)
			g_error ("could not open log: '%s'", EGG_LOG_FILE);
	}

	/* ITS4: ignore, debug text always NULL terminated */
	count = write (fd, buffer, strlen (buffer));
	if (count == -1)
		g_warning ("could not write %s", buffer);
	/* newline */
	count = write (fd, "\n", 1);
	if (count == -1)
		g_warning ("could not write newline");
}

/**
 * pk_print_line:
 **/
static void
pk_print_line (const gchar *func, const gchar *file, const int line, const gchar *buffer, guint color)
{
	gchar *str_time;
	gchar *header;
	time_t the_time;
	GThread *thread;

	time (&the_time);
	str_time = g_new0 (gchar, 255);
	strftime (str_time, 254, "%H:%M:%S", localtime (&the_time));
	thread = g_thread_self ();

	/* generate header text */
	header = g_strdup_printf ("TI:%s\tTH:%p\tFI:%s\tFN:%s,%d", str_time, thread, file, func, line);
	g_free (str_time);

	/* always in light green */
	pk_set_console_mode (CONSOLE_GREEN);
	printf ("%s\n", header);

	/* different colors according to the severity */
	pk_set_console_mode (color);
	printf (" - %s\n", buffer);
	pk_set_console_mode (CONSOLE_RESET);

	/* log to a file */
	if (egg_debug_is_logging ()) {
		pk_log_line (header);
		pk_log_line (buffer);
	}

	/* flush this output, as we need to debug */
	fflush (stdout);

	g_free (header);
}

/**
 * egg_debug_real:
 **/
void
egg_debug_real (const gchar *func, const gchar *file, const int line, const gchar *format, ...)
{
	va_list args;
	gchar *buffer = NULL;

	if (!egg_debug_enabled ())
		return;

	va_start (args, format);
	g_vasprintf (&buffer, format, args);
	va_end (args);

	pk_print_line (func, file, line, buffer, CONSOLE_BLUE);

	g_free(buffer);
}

/**
 * egg_warning_real:
 **/
void
egg_warning_real (const gchar *func, const gchar *file, const int line, const gchar *format, ...)
{
	va_list args;
	gchar *buffer = NULL;

	if (!egg_debug_enabled ())
		return;

	va_start (args, format);
	g_vasprintf (&buffer, format, args);
	va_end (args);

	/* do extra stuff for a warning */
	if (!egg_debug_is_console ())
		printf ("*** WARNING ***\n");
	pk_print_line (func, file, line, buffer, CONSOLE_RED);

	g_free(buffer);
}

/**
 * egg_error_real:
 **/
void
egg_error_real (const gchar *func, const gchar *file, const int line, const gchar *format, ...)
{
	va_list args;
	gchar *buffer = NULL;

	va_start (args, format);
	g_vasprintf (&buffer, format, args);
	va_end (args);

	/* do extra stuff for a warning */
	if (!egg_debug_is_console ())
		printf ("*** ERROR ***\n");
	pk_print_line (func, file, line, buffer, CONSOLE_RED);
	g_free(buffer);

	/* we want to fix this! */
	egg_debug_backtrace ();

	exit (1);
}

/**
 * egg_debug_enabled:
 *
 * Returns: TRUE if we have debugging enabled
 **/
gboolean
egg_debug_enabled (void)
{
	const gchar *env;
	env = g_getenv (EGG_VERBOSE);
	return (g_strcmp0 (env, "1") == 0);
}

/**
 * egg_debug_is_logging:
 *
 * Returns: TRUE if we have logging enabled
 **/
gboolean
egg_debug_is_logging (void)
{
	const gchar *env;
	env = g_getenv (EGG_LOGGING);
	return (g_strcmp0 (env, "1") == 0);
}

/**
 * egg_debug_is_console:
 *
 * Returns: TRUE if we have debugging enabled
 **/
gboolean
egg_debug_is_console (void)
{
	const gchar *env;
	env = g_getenv (EGG_CONSOLE);
	return (g_strcmp0 (env, "1") == 0);
}

/**
 * egg_debug_set_logging:
 **/
void
egg_debug_set_logging (gboolean enabled)
{
	if (enabled)
		g_setenv (EGG_LOGGING, "1", TRUE);
	else
		g_setenv (EGG_LOGGING, "0", TRUE);

	if (egg_debug_is_logging ())
		egg_debug ("logging to %s", EGG_LOG_FILE);
}

/**
 * egg_debug_init:
 * @debug: If we should print out verbose logging
 **/
void
egg_debug_init (gboolean debug)
{
	/* check if we are on console */
	if (isatty (fileno (stdout)) == 1)
		g_setenv (EGG_CONSOLE, "1", FALSE);
	else
		g_setenv (EGG_CONSOLE, "0", FALSE);
	if (debug)
		g_setenv (EGG_VERBOSE, "1", FALSE);
	else
		g_setenv (EGG_VERBOSE, "0", FALSE);
	egg_debug ("Verbose debugging %i (on console %i)%s", egg_debug_enabled (), egg_debug_is_console (), EGG_VERBOSE);
}