/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.
*/
package com.hp.hpl.jena.sparql.sse.writers;
import org.apache.jena.atlas.io.IndentedLineBuffer ;
import org.apache.jena.atlas.io.IndentedWriter ;
import com.hp.hpl.jena.sparql.algebra.Op ;
import com.hp.hpl.jena.sparql.algebra.op.OpBGP ;
import com.hp.hpl.jena.sparql.core.BasicPattern ;
import com.hp.hpl.jena.sparql.expr.ExprAggregator ;
import com.hp.hpl.jena.sparql.expr.Expr ;
import com.hp.hpl.jena.sparql.expr.ExprFunction ;
import com.hp.hpl.jena.sparql.expr.ExprFunctionOp ;
import com.hp.hpl.jena.sparql.expr.ExprList ;
import com.hp.hpl.jena.sparql.expr.ExprVar ;
import com.hp.hpl.jena.sparql.expr.ExprVisitorFunction ;
import com.hp.hpl.jena.sparql.expr.NodeValue ;
import com.hp.hpl.jena.sparql.serializer.SerializationContext ;
import com.hp.hpl.jena.sparql.sse.Tags ;
public class WriterExpr
{
public static String asString(Expr expr)
{
IndentedLineBuffer b = new IndentedLineBuffer() ;
output(b, expr, null) ;
return b.asString() ;
}
public static void output(IndentedWriter out, ExprList exprs, SerializationContext sCxt)
{
output(out, exprs, true, true, sCxt) ;
}
public static void output(IndentedWriter out, ExprList exprs, boolean withTag, boolean unlist, SerializationContext sCxt)
{
if ( exprs.size() == 0 )
{
out.print("()") ;
return ;
}
if ( exprs.size() == 1 && unlist )
{
output(out, exprs.get(0), sCxt) ;
return ;
}
out.print("(") ;
if ( withTag )
{
out.print(Tags.tagExprList) ;
out.print(" ") ;
}
for ( int i = 0 ; i < exprs.size() ; i++ )
{
if ( i != 0 ) out.print(" ") ;
output(out, exprs.get(i), sCxt) ;
}
out.print(")") ;
}
private static void outputTail(IndentedWriter out, ExprList exprs, SerializationContext sCxt)
{
for ( int i = 0 ; i < exprs.size() ; i++ )
{
out.print(" ") ;
output(out, exprs.get(i), sCxt) ;
}
out.print(")") ;
}
public static void output(IndentedWriter out, Expr expr, SerializationContext sCxt)
{
FmtExprPrefixVisitor fmt = new FmtExprPrefixVisitor(out, sCxt) ;
expr.visit(fmt) ;
}
// ----
static final boolean ONELINE = true ;
static class FmtExprPrefixVisitor extends ExprVisitorFunction
{
IndentedWriter out ;
SerializationContext context ;
public FmtExprPrefixVisitor(IndentedWriter writer, SerializationContext cxt)
{
out = writer ;
context = cxt ;
}
@Override
public void startVisit() {}
@Override
protected void visitExprFunction(ExprFunction func)
{
out.print("(") ;
String n = null ;
if ( func.getOpName() != null )
n = func.getOpName() ;
if ( n == null )
n = func.getFunctionName(context) ;
out.print(n) ;
out.incIndent() ;
for ( int i = 1 ; ; i++ )
{
Expr expr = func.getArg(i) ;
if ( expr == null )
break ;
// endLine() ;
out.print(' ') ;
expr.visit(this) ;
}
out.print(")") ;
out.decIndent() ;
}
@Override
public void visit(ExprFunctionOp funcOp)
{
out.print("(") ;
// How far we are from current indent to current location
// (beginning of operator name)
int x = out.getCurrentOffset() ;
// Indent to "("
out.incIndent(x) ;
out.print(funcOp.getFunctionName(context)) ;
out.incIndent() ;
Op op = funcOp.getGraphPattern() ;
if ( oneLine(op) )
out.print(" ") ;
else
out.ensureStartOfLine() ;
//Ensures we are unit indent under the (operator ...)
//Without trappings.
WriterOp.outputNoPrologue(out, funcOp.getGraphPattern(), context) ;
out.decIndent() ;
out.decIndent(x) ;
out.print(")") ;
return ;
}
private static boolean oneLine(Op op)
{
if ( OpBGP.isBGP(op) )
{
BasicPattern bgp = ((OpBGP)op).getPattern() ;
if ( bgp.getList().size() <= 1 )
return true ;
}
return false ;
}
@Override
public void visit(NodeValue nv)
{
out.print(nv.asQuotedString(context)) ;
}
@Override
public void visit(ExprVar nv)
{
out.print(nv.toPrefixString()) ;
}
@Override
public void visit(ExprAggregator eAgg)
{
out.print(eAgg.getAggregator().toPrefixString()) ;
}
@Override
public void finishVisit() { out.flush() ; }
private void endLine()
{
if ( ONELINE )
out.print(' ') ;
else
out.println() ;
}
}
}