/**
 * FreeRDP: A Remote Desktop Protocol Implementation
 * Time Zone Redirection Table Generator
 *
 * Copyright 2012 Marc-Andre Moreau <marcandre.moreau@gmail.com>
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *	 http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
/* Run with ' csi scripts/TimeZones.csx' from freerdp checkout root */

using System;
using System.IO;
using System.Globalization;
using System.Collections.ObjectModel;

struct SYSTEM_TIME_ENTRY
{
    public UInt16 wYear;
    public UInt16 wMonth;
    public UInt16 wDayOfWeek;
    public UInt16 wDay;
    public UInt16 wHour;
    public UInt16 wMinute;
    public UInt16 wSecond;
    public UInt16 wMilliseconds;
};

struct TIME_ZONE_RULE_ENTRY
{
    public long TicksStart;
    public long TicksEnd;
    public Int32 DaylightDelta;
    public SYSTEM_TIME_ENTRY StandardDate;
    public SYSTEM_TIME_ENTRY DaylightDate;
};

struct TIME_ZONE_ENTRY
{
    public string Id;
    public Int32 Bias;
    public bool SupportsDST;
    public string DisplayName;
    public string StandardName;
    public string DaylightName;
    public string RuleTable;
    public UInt32 RuleTableCount;
};

int i;
UInt32 index;
const string file = @"winpr/libwinpr/timezone/TimeZones.c";
TimeZoneInfo.AdjustmentRule[] rules;
StreamWriter stream = new StreamWriter(file, false);
ReadOnlyCollection<TimeZoneInfo> timeZones = TimeZoneInfo.GetSystemTimeZones();

Console.WriteLine("Updating " + file);
stream.WriteLine("/* ");
stream.WriteLine(" * Automatically generated with scripts/TimeZones.csx");
stream.WriteLine(" */ ");
stream.WriteLine();

stream.WriteLine("#include \"TimeZones.h\"");
stream.WriteLine();

index = 0;

foreach (TimeZoneInfo timeZone in timeZones)
{
    rules = timeZone.GetAdjustmentRules();

    if ((!timeZone.SupportsDaylightSavingTime) || (rules.Length < 1))
    {
        index++;
        continue;
    }

    stream.WriteLine("static const TIME_ZONE_RULE_ENTRY TimeZoneRuleTable_{0}[] =", index);
    stream.WriteLine("{");

    i = 0;
    foreach (TimeZoneInfo.AdjustmentRule rule in rules)
    {
        DateTime time;
        TIME_ZONE_RULE_ENTRY tzr;
        TimeZoneInfo.TransitionTime transition;

        tzr.TicksStart = rule.DateEnd.ToUniversalTime().Ticks;
        tzr.TicksEnd = rule.DateStart.ToUniversalTime().Ticks;
        tzr.DaylightDelta = (Int32)rule.DaylightDelta.TotalMinutes;

        transition = rule.DaylightTransitionEnd;
        time = transition.TimeOfDay;

        tzr.StandardDate.wYear = (UInt16)0;
        tzr.StandardDate.wMonth = (UInt16)transition.Month;
        tzr.StandardDate.wDayOfWeek = (UInt16)transition.DayOfWeek;
        tzr.StandardDate.wDay = (UInt16)transition.Week;
        tzr.StandardDate.wHour = (UInt16)time.Hour;
        tzr.StandardDate.wMinute = (UInt16)time.Minute;
        tzr.StandardDate.wSecond = (UInt16)time.Second;
        tzr.StandardDate.wMilliseconds = (UInt16)time.Millisecond;

        transition = rule.DaylightTransitionStart;
        time = transition.TimeOfDay;

        tzr.DaylightDate.wYear = (UInt16)0;
        tzr.DaylightDate.wMonth = (UInt16)transition.Month;
        tzr.DaylightDate.wDayOfWeek = (UInt16)transition.DayOfWeek;
        tzr.DaylightDate.wDay = (UInt16)transition.Week;
        tzr.DaylightDate.wHour = (UInt16)time.Hour;
        tzr.DaylightDate.wMinute = (UInt16)time.Minute;
        tzr.DaylightDate.wSecond = (UInt16)time.Second;
        tzr.DaylightDate.wMilliseconds = (UInt16)time.Millisecond;

        stream.Write("\t{");
        stream.Write(" {0}ULL, {1}ULL, {2},", tzr.TicksStart, tzr.TicksEnd, tzr.DaylightDelta);

        stream.Write(" { ");
        stream.Write("{0}, {1}, {2}, {3}, {4}, {5}, {6}, {7}",
            tzr.StandardDate.wYear, tzr.StandardDate.wMonth, tzr.StandardDate.wDayOfWeek,
            tzr.StandardDate.wDay, tzr.StandardDate.wHour, tzr.StandardDate.wMinute,
            tzr.StandardDate.wSecond, tzr.StandardDate.wMilliseconds);
        stream.Write(" }, ");

        stream.Write("{ ");
        stream.Write("{0}, {1}, {2}, {3}, {4}, {5}, {6}, {7}",
            tzr.DaylightDate.wYear, tzr.DaylightDate.wMonth, tzr.DaylightDate.wDayOfWeek,
            tzr.DaylightDate.wDay, tzr.DaylightDate.wHour, tzr.DaylightDate.wMinute,
            tzr.DaylightDate.wSecond, tzr.DaylightDate.wMilliseconds);
        stream.Write(" },");

        if (++i < rules.Length)
            stream.WriteLine(" },");
        else
            stream.WriteLine(" }");
    }

    stream.WriteLine("};");
    stream.WriteLine();
    index++;
}

index = 0;
stream.WriteLine("const TIME_ZONE_ENTRY TimeZoneTable[] =");
stream.WriteLine("{");

foreach (TimeZoneInfo timeZone in timeZones)
{
    TIME_ZONE_ENTRY tz;
    TimeSpan offset = timeZone.BaseUtcOffset;

    rules = timeZone.GetAdjustmentRules();

    tz.Id = timeZone.Id;
    tz.Bias = -(Int32)offset.TotalMinutes;

    tz.SupportsDST = timeZone.SupportsDaylightSavingTime;

    tz.DisplayName = timeZone.DisplayName;
    tz.StandardName = timeZone.StandardName;
    tz.DaylightName = timeZone.DaylightName;

    if ((!tz.SupportsDST) || (rules.Length < 1))
    {
        tz.RuleTableCount = 0;
        tz.RuleTable = "NULL";
    }
    else
    {
        tz.RuleTableCount = (UInt32)rules.Length;
        tz.RuleTable = "TimeZoneRuleTable_" + index;
    }

    stream.WriteLine("\t{");

    stream.WriteLine("\t\t\"{0}\", {1}, {2}, \"{3}\",",
        tz.Id, tz.Bias, tz.SupportsDST ? "TRUE" : "FALSE", tz.DisplayName);

    stream.WriteLine("\t\t\"{0}\", \"{1}\",", tz.StandardName, tz.DaylightName);
    stream.WriteLine("\t\t{0}, {1}", tz.RuleTable, tz.RuleTableCount);

    index++;

    if ((int)index < timeZones.Count)
        stream.WriteLine("\t},");
    else
        stream.WriteLine("\t}");
}
stream.WriteLine("};");
stream.WriteLine();
stream.WriteLine("const size_t TimeZoneTableNrElements = ARRAYSIZE(TimeZoneTable);");
stream.WriteLine();

stream.Close();