public IfpRecord ReadIfpRecord
(
long offset
)
{
IfpRecord result = IfpRecord.Read(Ifp, offset);
return(result);
}
/// <summary>
/// ibatrak чтение заголовка записи IFP (для подсчета количества ссылок)
/// </summary>
public static IfpRecord ReadLeader
(
Stream stream,
long offset
)
{
stream.Position = offset;
IfpRecord result = new IfpRecord
{
LowOffset = stream.ReadInt32Network(),
HighOffset = stream.ReadInt32Network(),
TotalLinkCount = stream.ReadInt32Network(),
BlockLinkCount = stream.ReadInt32Network(),
Capacity = stream.ReadInt32Network()
};
return(result);
}
/// <summary>
/// Read the record.
/// </summary>
public static IfpRecord Read
(
[NotNull] Stream stream,
long offset
)
{
stream.Position = offset;
IfpRecord result = new IfpRecord
{
LowOffset = stream.ReadInt32Network(),
HighOffset = stream.ReadInt32Network(),
TotalLinkCount = stream.ReadInt32Network(),
BlockLinkCount = stream.ReadInt32Network(),
Capacity = stream.ReadInt32Network()
};
// ibatrak чтение вложенных записей в спец блоке
// Специальный формат записи .ifp
// В этом случае первой записью является специальный блок,
// который представляет собой заголовок (обыкновенного формата),
// в котором смещения имеют специальные значения = -1001
if (result.LowOffset == -1001 && result.HighOffset == -1001)
{
// irbis64.dll делает так
// читает первые 24 байта блока спец ссылок
// (это 2 записи)
// записи с реальными адресами идут через одну
// берет вторую запись, адрес из нее в файле
// и читает записеи IFP
// по количеству result.BlockLinkCount
// первую запись спец блока просто пропускаем,
// читаем сразу вторую
stream.Position += 12;
SpecialPostingBlockEntry entry = new SpecialPostingBlockEntry
{
Posting = stream.ReadInt32Network(),
Low = stream.ReadInt32Network(),
High = stream.ReadInt32Network()
};
stream.Position = entry.Offset;
IfpRecord[] nestedRecords
= new IfpRecord[result.BlockLinkCount];
for (int i = 0; i < result.BlockLinkCount; i++)
{
var nestedRecord = Read(stream, stream.Position);
nestedRecords[i] = nestedRecord;
// Last record in the list must have
// negative offset values
if (nestedRecord.LowOffset == -1 &&
nestedRecord.HighOffset == -1)
{
if (i != result.BlockLinkCount - 1)
{
throw new InvalidOperationException
(
"IFP reading error"
);
}
break;
}
if (nestedRecord.FullOffset < 0)
{
throw new InvalidOperationException
(
"IFP reading error"
);
}
stream.Position = nestedRecord.FullOffset;
}
TermLink[] links = nestedRecords
.SelectMany(r => r.Links)
.ToArray();
if (links.Length != result.TotalLinkCount)
{
throw new InvalidOperationException
(
"IFP reading error"
);
}
result.Links.AddRange(links);
return(result);
}
//ibatrak до сюда
for (int i = 0; i < result.BlockLinkCount; i++)
{
TermLink link = TermLink.Read(stream);
result.Links.Add(link);
}
return(result);
}
public TermLink[] SearchStart
(
[CanBeNull] string key
)
{
List <TermLink> result = new List <TermLink>();
if (string.IsNullOrEmpty(key))
{
return(new TermLink[0]);
}
key = key.ToUpperInvariant();
NodeRecord firstNode = ReadNode(1);
NodeRecord rootNode = ReadNode(firstNode.Leader.Number);
NodeRecord currentNode = rootNode;
NodeItem goodItem = null;
while (true)
{
bool found = false;
bool beyond = false;
foreach (NodeItem item in currentNode.Items)
{
int compareResult = string.CompareOrdinal(item.Text, key);
if (compareResult > 0)
{
beyond = true;
break;
}
goodItem = item;
found = true;
}
if (goodItem == null)
{
break;
}
if (found)
{
if (beyond || (currentNode.Leader.Next == -1))
{
if (goodItem.RefersToLeaf)
{
goto FOUND;
}
currentNode = ReadNode(goodItem.LowOffset);
}
else
{
currentNode = ReadNext(currentNode);
}
}
else
{
if (goodItem.RefersToLeaf)
{
goto FOUND;
}
currentNode = ReadNode(goodItem.LowOffset);
}
//Console.WriteLine(currentNode);
}
FOUND:
if (goodItem != null)
{
currentNode = ReadLeaf(goodItem.LowOffset);
while (true)
{
foreach (NodeItem item in currentNode.Items)
{
int compareResult = string.CompareOrdinal(item.Text, key);
if (compareResult >= 0)
{
bool starts = item.Text.StartsWith(key);
if ((compareResult > 0) && !starts)
{
goto DONE;
}
if (starts)
{
IfpRecord ifp = ReadIfpRecord(item.FullOffset);
result.AddRange(ifp.Links);
}
}
}
if (currentNode.Leader.Next > 0)
{
currentNode = ReadNext(currentNode);
}
}
}
DONE:
return(result
.Distinct()
.ToArray());
}
public TermLink[] SearchExact
(
[CanBeNull] string key
)
{
if (string.IsNullOrEmpty(key))
{
return(new TermLink[0]);
}
key = key.ToUpperInvariant();
NodeRecord firstNode = ReadNode(1);
NodeRecord rootNode = ReadNode(firstNode.Leader.Number);
NodeRecord currentNode = rootNode;
NodeItem goodItem = null;
while (true)
{
bool found = false;
bool beyond = false;
foreach (NodeItem item in currentNode.Items)
{
int compareResult = string.CompareOrdinal(item.Text, key);
if (compareResult > 0)
{
beyond = true;
break;
}
goodItem = item;
found = true;
if ((compareResult == 0) &&
currentNode.IsLeaf)
{
goto FOUND;
}
}
if (goodItem == null)
{
break;
}
if (found)
{
if (beyond || (currentNode.Leader.Next == -1))
{
currentNode = goodItem.RefersToLeaf
? ReadLeaf(goodItem.LowOffset)
: ReadNode(goodItem.LowOffset);
}
else
{
currentNode = ReadNext(currentNode);
}
}
else
{
currentNode = goodItem.RefersToLeaf
? ReadLeaf(goodItem.LowOffset)
: ReadNode(goodItem.LowOffset);
}
//Console.WriteLine(currentNode);
}
FOUND:
if (goodItem != null)
{
IfpRecord ifp = ReadIfpRecord(goodItem.FullOffset);
return(ifp.Links.ToArray());
}
return(new TermLink[0]);
}
public TermLink[] SearchExact
(
[CanBeNull] string key
)
{
if (string.IsNullOrEmpty(key))
{
return(new TermLink[0]);
}
try
{
key = key.ToUpperInvariant();
NodeRecord firstNode = ReadNode(1);
NodeRecord rootNode = ReadNode(firstNode.Leader.Number);
NodeRecord currentNode = rootNode;
NodeItem goodItem = null;
while (true)
{
bool found = false;
bool beyond = false;
foreach (NodeItem item in currentNode.Items)
{
int compareResult = string.CompareOrdinal(item.Text, key);
if (compareResult > 0)
{
beyond = true;
break;
}
goodItem = item;
found = true;
if (compareResult == 0 &&
currentNode.IsLeaf)
{
goto FOUND;
}
}
if (goodItem == null)
{
break;
}
if (found)
{
if (beyond || currentNode.Leader.Next == -1)
{
currentNode = goodItem.RefersToLeaf
? ReadLeaf(goodItem.LowOffset)
: ReadNode(goodItem.LowOffset);
}
else
{
currentNode = ReadNext(currentNode);
}
}
else
{
currentNode = goodItem.RefersToLeaf
? ReadLeaf(goodItem.LowOffset)
: ReadNode(goodItem.LowOffset);
}
//Console.WriteLine(currentNode);
}
FOUND:
if (goodItem != null)
{
// ibatrak записи могут иметь ссылки на следующие
List <TermLink> result = new List <TermLink>();
long offset = goodItem.FullOffset;
while (offset > 0)
{
IfpRecord ifp = ReadIfpRecord(offset);
result.AddRange(ifp.Links);
offset = ifp.FullOffset > 0
? ifp.FullOffset
: 0;
}
return(result
.Distinct()
.ToArray());
//ibatrak до сюда
}
}
catch (Exception ex)
{
Debug.WriteLine(ex);
}
return(new TermLink[0]);
}