/***************************************************************************
 *       Copyright (c) 2003 by Marcel Wiesweg, Rolf Hakenes                *
 *                                                                         *
 *   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.                                   *
 *                                                                         *
 *   $Id: util.c 5.1 2021/05/19 11:55:00 kls Exp $
 *                                                                         *
 ***************************************************************************/

#include <string.h>
#include "util.h"

namespace SI {

/*---------------------------- CharArray ----------------------------*/

CharArray::CharArray() : data_(0), off(0) {
}

CharArray::~CharArray() {
   if (!data_)
      return;
   if (--data_->count_ == 0)
      delete data_;
}

CharArray::CharArray(const CharArray &f) : data_(f.data_), off(f.off) {
   if (data_)
      ++ data_->count_;
}

CharArray& CharArray::operator=(const CharArray &f) {
    // DO NOT CHANGE THE ORDER OF THESE STATEMENTS!
    // (This order properly handles self-assignment)
    if (f.data_) {
      ++ f.data_->count_;
    }
    if (data_) {
      if (--data_->count_ == 0)
         delete data_;
    }
    data_ = f.data_;
    off = f.off;
    return *this;
}

void CharArray::assign(const unsigned char*data, int size, bool doCopy) {
    //immutable
    if (!data_)
      data_= doCopy ? (Data*)new DataOwnData() : (Data*)new DataForeignData();
    // This method might need to change things in *data_
    // Thus it first checks if this is the only pointer to *data_
    if (data_->count_ > 1) {
      Data* d = doCopy ? (Data*)new DataOwnData() : (Data*)new DataForeignData();
      -- data_->count_;
      data_ = d;
    }
    data_->assign(data, size);
}

bool CharArray::operator==(const char *string) const {
   //here we can use strcmp, string is null-terminated.
   if (!data_)
      return false;
   return data_->size ? (!strcmp((const char*)data_->data, string)) : string[0]==0;
}

bool CharArray::operator==(const CharArray &other) const {
   if (!data_ || !other.data_)
      return !(data_ || other.data_); //true if both empty

   if (data_->size != other.data_->size)
      return false;

   //do _not_ use strcmp! Data is not necessarily null-terminated.
   for (int i=0;i<data_->size;i++)
      if (data_->data[i] != other.data_->data[i])
         return false;
   return true;
}

CharArray CharArray::operator+(const int offset) const {
   CharArray f(*this);
   f.off+=offset;
   return f;
}

CharArray::Data::Data() : data(0), size(0), count_(1), valid(true) {
   /*
   lockingPid = 0;
   locked = 0;
   pthread_mutex_init(&mutex, NULL);
   */
}

CharArray::Data::~Data() {
   /*
   if (locked)
      pthread_mutex_unlock(&mutex);
   pthread_mutex_destroy(&mutex);
   */
}

/*CharArray::Data::Data(const Data& d) : count_(1) {
   size=0;
   data=0;

   lockingPid = 0;
   locked = 0;
   pthread_mutex_init(&mutex, NULL);
}*/

CharArray::DataOwnData::~DataOwnData() {
   Delete();
}

void CharArray::DataOwnData::assign(const unsigned char*d, int s) {
   Delete();
   if (!d || s > 100000 || s <= 0) // ultimate plausibility check
      return;
   size=s;
   unsigned char *newdata=new unsigned char[size];
   memcpy(newdata, d, size);
   data=newdata;
}

void CharArray::DataOwnData::Delete() {
   delete[] data;
   size=0;
   data=0;
}

CharArray::DataForeignData::~DataForeignData() {
   Delete();
}

void CharArray::DataForeignData::assign(const unsigned char*d, int s) {
   size=s;
   data=d;
}

void CharArray::DataForeignData::Delete() {
   //do not delete!
}

/*
void CharArray::Data::assign(int s) {
   if (data)
      delete[] data;
   size=s;
   if (size) { //new assignment may be zero length
      data=new unsigned char[size];
      memset(data, 0, size);
   }
}

void CharArray::Data::Lock(void)
{
  if ( !pthread_equal(pthread_self(), lockingPid) || !locked) {
     pthread_mutex_lock(&mutex);
     lockingPid = pthread_self();
     }
  locked++;
}

void CharArray::Data::Unlock(void)
{
   if (!--locked) {
     lockingPid = 0;
     pthread_mutex_unlock(&mutex);
   }
}
*/

Parsable::Parsable() {
   parsed=false;
}

void Parsable::CheckParse() {
   if (!parsed) {
      parsed=true;
      Parse();
   }
}

//taken and adapted from libdtv, (c) Rolf Hakenes and VDR, (c) Klaus Schmidinger
time_t DVBTime::getTime(unsigned char date_hi, unsigned char date_lo, unsigned char time_hour, unsigned char time_minute, unsigned char time_second) {
   u_int16_t mjd = date_hi << 8 | date_lo;
   struct tm t;

   t.tm_sec = bcdToDec(time_second);
   t.tm_min = bcdToDec(time_minute);
   t.tm_hour = bcdToDec(time_hour);

   int k;
   t.tm_year = (int) ((mjd - 15078.2) / 365.25);
   t.tm_mon = (int) ((mjd - 14956.1 - (int)(t.tm_year * 365.25)) / 30.6001);
   t.tm_mday = (int) (mjd - 14956 - (int)(t.tm_year * 365.25) - (int)(t.tm_mon * 30.6001));
   k = (t.tm_mon == 14 || t.tm_mon == 15) ? 1 : 0;
   t.tm_year = t.tm_year + k;
   t.tm_mon = t.tm_mon - 1 - k * 12;
   t.tm_mon--;

   t.tm_isdst = -1;
   t.tm_gmtoff = 0;

   return timegm(&t);
}

time_t DVBTime::getDuration(unsigned char time_hour, unsigned char time_minute, unsigned char time_second) {
   return
     bcdToDec(time_second)
   + bcdToDec(time_minute) * 60
   + bcdToDec(time_hour) *3600;
}

//taken and adapted from libdtv, (c) Rolf Hakenes
// CRC32 lookup table for polynomial 0x04c11db7
u_int32_t CRC32::crc_table[256] = {
   0x00000000, 0x04c11db7, 0x09823b6e, 0x0d4326d9, 0x130476dc, 0x17c56b6b,
   0x1a864db2, 0x1e475005, 0x2608edb8, 0x22c9f00f, 0x2f8ad6d6, 0x2b4bcb61,
   0x350c9b64, 0x31cd86d3, 0x3c8ea00a, 0x384fbdbd, 0x4c11db70, 0x48d0c6c7,
   0x4593e01e, 0x4152fda9, 0x5f15adac, 0x5bd4b01b, 0x569796c2, 0x52568b75,
   0x6a1936c8, 0x6ed82b7f, 0x639b0da6, 0x675a1011, 0x791d4014, 0x7ddc5da3,
   0x709f7b7a, 0x745e66cd, 0x9823b6e0, 0x9ce2ab57, 0x91a18d8e, 0x95609039,
   0x8b27c03c, 0x8fe6dd8b, 0x82a5fb52, 0x8664e6e5, 0xbe2b5b58, 0xbaea46ef,
   0xb7a96036, 0xb3687d81, 0xad2f2d84, 0xa9ee3033, 0xa4ad16ea, 0xa06c0b5d,
   0xd4326d90, 0xd0f37027, 0xddb056fe, 0xd9714b49, 0xc7361b4c, 0xc3f706fb,
   0xceb42022, 0xca753d95, 0xf23a8028, 0xf6fb9d9f, 0xfbb8bb46, 0xff79a6f1,
   0xe13ef6f4, 0xe5ffeb43, 0xe8bccd9a, 0xec7dd02d, 0x34867077, 0x30476dc0,
   0x3d044b19, 0x39c556ae, 0x278206ab, 0x23431b1c, 0x2e003dc5, 0x2ac12072,
   0x128e9dcf, 0x164f8078, 0x1b0ca6a1, 0x1fcdbb16, 0x018aeb13, 0x054bf6a4,
   0x0808d07d, 0x0cc9cdca, 0x7897ab07, 0x7c56b6b0, 0x71159069, 0x75d48dde,
   0x6b93dddb, 0x6f52c06c, 0x6211e6b5, 0x66d0fb02, 0x5e9f46bf, 0x5a5e5b08,
   0x571d7dd1, 0x53dc6066, 0x4d9b3063, 0x495a2dd4, 0x44190b0d, 0x40d816ba,
   0xaca5c697, 0xa864db20, 0xa527fdf9, 0xa1e6e04e, 0xbfa1b04b, 0xbb60adfc,
   0xb6238b25, 0xb2e29692, 0x8aad2b2f, 0x8e6c3698, 0x832f1041, 0x87ee0df6,
   0x99a95df3, 0x9d684044, 0x902b669d, 0x94ea7b2a, 0xe0b41de7, 0xe4750050,
   0xe9362689, 0xedf73b3e, 0xf3b06b3b, 0xf771768c, 0xfa325055, 0xfef34de2,
   0xc6bcf05f, 0xc27dede8, 0xcf3ecb31, 0xcbffd686, 0xd5b88683, 0xd1799b34,
   0xdc3abded, 0xd8fba05a, 0x690ce0ee, 0x6dcdfd59, 0x608edb80, 0x644fc637,
   0x7a089632, 0x7ec98b85, 0x738aad5c, 0x774bb0eb, 0x4f040d56, 0x4bc510e1,
   0x46863638, 0x42472b8f, 0x5c007b8a, 0x58c1663d, 0x558240e4, 0x51435d53,
   0x251d3b9e, 0x21dc2629, 0x2c9f00f0, 0x285e1d47, 0x36194d42, 0x32d850f5,
   0x3f9b762c, 0x3b5a6b9b, 0x0315d626, 0x07d4cb91, 0x0a97ed48, 0x0e56f0ff,
   0x1011a0fa, 0x14d0bd4d, 0x19939b94, 0x1d528623, 0xf12f560e, 0xf5ee4bb9,
   0xf8ad6d60, 0xfc6c70d7, 0xe22b20d2, 0xe6ea3d65, 0xeba91bbc, 0xef68060b,
   0xd727bbb6, 0xd3e6a601, 0xdea580d8, 0xda649d6f, 0xc423cd6a, 0xc0e2d0dd,
   0xcda1f604, 0xc960ebb3, 0xbd3e8d7e, 0xb9ff90c9, 0xb4bcb610, 0xb07daba7,
   0xae3afba2, 0xaafbe615, 0xa7b8c0cc, 0xa379dd7b, 0x9b3660c6, 0x9ff77d71,
   0x92b45ba8, 0x9675461f, 0x8832161a, 0x8cf30bad, 0x81b02d74, 0x857130c3,
   0x5d8a9099, 0x594b8d2e, 0x5408abf7, 0x50c9b640, 0x4e8ee645, 0x4a4ffbf2,
   0x470cdd2b, 0x43cdc09c, 0x7b827d21, 0x7f436096, 0x7200464f, 0x76c15bf8,
   0x68860bfd, 0x6c47164a, 0x61043093, 0x65c52d24, 0x119b4be9, 0x155a565e,
   0x18197087, 0x1cd86d30, 0x029f3d35, 0x065e2082, 0x0b1d065b, 0x0fdc1bec,
   0x3793a651, 0x3352bbe6, 0x3e119d3f, 0x3ad08088, 0x2497d08d, 0x2056cd3a,
   0x2d15ebe3, 0x29d4f654, 0xc5a92679, 0xc1683bce, 0xcc2b1d17, 0xc8ea00a0,
   0xd6ad50a5, 0xd26c4d12, 0xdf2f6bcb, 0xdbee767c, 0xe3a1cbc1, 0xe760d676,
   0xea23f0af, 0xeee2ed18, 0xf0a5bd1d, 0xf464a0aa, 0xf9278673, 0xfde69bc4,
   0x89b8fd09, 0x8d79e0be, 0x803ac667, 0x84fbdbd0, 0x9abc8bd5, 0x9e7d9662,
   0x933eb0bb, 0x97ffad0c, 0xafb010b1, 0xab710d06, 0xa6322bdf, 0xa2f33668,
   0xbcb4666d, 0xb8757bda, 0xb5365d03, 0xb1f740b4};

u_int32_t CRC32::crc32 (const char *d, int len, u_int32_t crc)
{
   int i;
   const unsigned char *u=(unsigned char*)d; // Saves '& 0xff'

   for (i=0; i<len; i++)
      crc = (crc << 8) ^ crc_table[((crc >> 24) ^ *u++)];

   return crc;
}

CRC32::CRC32(const char *d, int len, u_int32_t CRCvalue) {
   data=d;
   length=len;
   value=CRCvalue;
}

} //end of namespace
