/*
 * Copyright 2015, Axel Dörfler, axeld@pinc-software.de.
 * Copyright 2004, Jérôme Duval, jerome.duval@free.fr.
 * Copyright 2010, 2012, Oliver Tappe <zooey@hirschkaefer.de>
 * Distributed under the terms of the MIT License.
 */


//! Initialize real time clock, and time zone offset


#include "InitRealTimeClockJob.h"

#include <stdio.h>

#include <File.h>
#include <FindDirectory.h>
#include <Message.h>
#include <TimeZone.h>

#include <syscalls.h>


using BSupportKit::BJob;


InitRealTimeClockJob::InitRealTimeClockJob()
        :
        BJob("init real time clock")
{
}


status_t
InitRealTimeClockJob::Execute()
{
        BPath path;
        status_t status = find_directory(B_USER_SETTINGS_DIRECTORY, &path);
        if (status == B_OK) {
                _SetRealTimeClockIsGMT(path);
                _SetTimeZoneOffset(path);
        }
        return status;
}


void
InitRealTimeClockJob::_SetRealTimeClockIsGMT(BPath path) const
{
        path.Append("RTC_time_settings");
        BFile file;
        status_t status = file.SetTo(path.Path(), B_READ_ONLY);
        if (status != B_OK) {
                fprintf(stderr, "Can't open RTC settings file\n");
                return;
        }

        char buffer[10];
        ssize_t bytesRead = file.Read(buffer, sizeof(buffer));
        if (bytesRead < 0) {
                fprintf(stderr, "Unable to read RTC settings file\n");
                return;
        }
        bool isGMT = strncmp(buffer, "local", 5) != 0;

        _kern_set_real_time_clock_is_gmt(isGMT);
        printf("RTC stores %s time.\n", isGMT ? "GMT" : "local" );
}


void
InitRealTimeClockJob::_SetTimeZoneOffset(BPath path) const
{
        path.Append("Time settings");
        BFile file;
        status_t status = file.SetTo(path.Path(), B_READ_ONLY);
        if (status != B_OK) {
                fprintf(stderr, "Can't open Time settings file\n");
                return;
        }

        BMessage settings;
        status = settings.Unflatten(&file);
        if (status != B_OK) {
                fprintf(stderr, "Unable to parse Time settings file\n");
                return;
        }
        BString timeZoneID;
        if (settings.FindString("timezone", &timeZoneID) != B_OK) {
                fprintf(stderr, "No timezone found\n");
                return;
        }
        int32 timeZoneOffset = BTimeZone(timeZoneID.String()).OffsetFromGMT();

        _kern_set_timezone(timeZoneOffset, timeZoneID.String(),
                timeZoneID.Length());
        printf("timezone is %s, offset is %" B_PRId32 " seconds from GMT.\n",
                timeZoneID.String(), timeZoneOffset);
}