/*
* Redberry: symbolic tensor computations.
*
* Copyright (c) 2010-2013:
* Stanislav Poslavsky <stvlpos@mail.ru>
* Bolotin Dmitriy <bolotin.dmitriy@gmail.com>
*
* This file is part of Redberry.
*
* Redberry 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 3 of the License, or
* (at your option) any later version.
*
* Redberry 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 Redberry. If not, see <http://www.gnu.org/licenses/>.
*/
package cc.redberry.core.indexmapping;
import cc.redberry.core.context.Context;
import cc.redberry.core.context.OutputFormat;
import cc.redberry.core.indices.InconsistentIndicesException;
import cc.redberry.core.indices.IndicesUtils;
/**
* Holds the intermediate information about mapping entry.
*
* @author Dmitry Bolotin
* @author Stanislav Poslavsky
* @since 1.0
*/
final class IndexMappingBufferRecord {
/*
* Mask 0b00000SUL
*
* S - initialized with different states U - "to" upper index mapped L -
* "to" lower index mapped
*
*/
byte states;
private final int toName;
public IndexMappingBufferRecord(int from, int to) {
this.toName = IndicesUtils.getNameWithType(to);
states |= 1 << IndicesUtils.getStateInt(to);
states |= (IndicesUtils.getStateInt(from) ^ IndicesUtils.getStateInt(to)) << 2;
}
public IndexMappingBufferRecord(byte usedStates, int indexName) {
this.states = usedStates;
this.toName = indexName;
}
public boolean tryMap(int from, int to) {
if (IndicesUtils.getNameWithType(to) != toName)
return false;
if ((IndicesUtils.getStateInt(from) != IndicesUtils.getStateInt(to)) != ((states & 0x4) == 0x4))
throw new InconsistentIndicesException(from);
if ((states & (1 << IndicesUtils.getStateInt(to))) != 0)
throw new InconsistentIndicesException(to);
states |= 1 << IndicesUtils.getStateInt(to);
return true;
}
/**
* @return name with type
*/
public int getIndexName() {
return toName;
}
// public int getFromRawState() {
// return ((states & 4) == 4 ? 0x80000000 : 0) ^ (((states & 1) ^ 1) << 31);
// }
//
// public int getToRawState() {
// return ((states & 1) ^ 1) << 31;
// }
public byte getStates() {
return states;
}
public int getToRawState() {
return (states & 1) == 0 ? 0x80000000 : 0;
}
public int getFromRawState() {
if ((states & 4) == 0)
return getToRawState();
else
return 0x80000000 ^ getToRawState();
}
public boolean getStatesBit(int bit) {
return ((states >>> bit) & 1) == 1;
}
public boolean isContracted() {
return (states & 3) == 3;
}
public boolean diffStatesInitialized() {
return (states & 4) == 4;
}
public int getRawDiffStateBit() {
return ((states & 4) << 29);
}
public void invertStates() {
if (isContracted()) return;
states ^= 3;
}
@Override
public IndexMappingBufferRecord clone() {
return new IndexMappingBufferRecord(states, toName);
}
@Override
public boolean equals(Object obj) {
if (obj == null)
return false;
if (getClass() != obj.getClass())
return false;
final IndexMappingBufferRecord other = (IndexMappingBufferRecord) obj;
if (this.states != other.states)
return false;
return this.toName == other.toName;
}
@Override
public int hashCode() {
return 31 * (31 * 7 + this.states) + this.toName;
}
@Override
public String toString() {
StringBuilder sb = new StringBuilder();
sb.append(Context.get().getIndexConverterManager().getSymbol(getIndexName(), OutputFormat.UTF8));
sb.append(":");
for (int i = 2; i >= 0; --i)
sb.append(getStatesBit(i) ? 1 : 0);
return sb.toString();
}
}