From: Mikko Rasa <tdb@tdb.fi>
Date: Sat, 26 Jan 2013 20:35:15 +0000 (+0200)
Subject: Add a function to get a BlockIter from a TrackIter
X-Git-Url: http://git.tdb.fi/?a=commitdiff_plain;h=32316772d422223827833366a7ee2d0a76d76ff1;p=r2c2.git

Add a function to get a BlockIter from a TrackIter
---

diff --git a/source/libr2c2/blockiter.h b/source/libr2c2/blockiter.h
index 1e8a383..362c918 100644
--- a/source/libr2c2/blockiter.h
+++ b/source/libr2c2/blockiter.h
@@ -1,9 +1,10 @@
 #ifndef LIBR2C2_BLOCKITER_H_
 #define LIBR2C2_BLOCKITER_H_
 
+#include "block.h"
+
 namespace R2C2 {
 
-class Block;
 class Route;
 class TrackIter;
 
diff --git a/source/libr2c2/trackiter.cpp b/source/libr2c2/trackiter.cpp
index c636d27..64d223e 100644
--- a/source/libr2c2/trackiter.cpp
+++ b/source/libr2c2/trackiter.cpp
@@ -1,4 +1,5 @@
 #include <algorithm>
+#include "blockiter.h"
 #include "track.h"
 #include "trackiter.h"
 #include "tracktype.h"
@@ -21,6 +22,40 @@ TrackIter::TrackIter(Track *t, unsigned e):
 		throw out_of_range("TrackIter::TrackIter");
 }
 
+BlockIter TrackIter::block_iter() const
+{
+	if(!_track)
+		return BlockIter();
+
+	Block &block = _track->get_block();
+	const vector<Block::Endpoint> &beps = block.get_endpoints();
+
+	if(_track->get_type().is_turnout())
+	{
+		/* A turnouts is the only track in its block.  Go ahead and find the
+		matching endpoint in the block. */
+		for(unsigned i=0; i<beps.size(); ++i)
+			if(beps[i].track==_track && beps[i].track_ep==_entry)
+				return BlockIter(&block, i);
+	}
+	else
+	{
+		TrackIter rev = reverse();
+		while(rev && &rev.track()->get_block()==&block)
+		{
+			TrackIter fwd = rev.reverse();
+
+			for(unsigned i=0; i<beps.size(); ++i)
+				if(beps[i].track==fwd.track() && beps[i].track_ep==fwd.entry())
+					return BlockIter(&block, i);
+
+			rev = rev.next();
+		}
+	}
+
+	throw logic_error("internal error (didn't find block entry endpoint)");
+}
+
 const TrackType::Endpoint &TrackIter::endpoint() const
 {
 	if(!_track)
diff --git a/source/libr2c2/trackiter.h b/source/libr2c2/trackiter.h
index 63d98e2..3a63386 100644
--- a/source/libr2c2/trackiter.h
+++ b/source/libr2c2/trackiter.h
@@ -7,6 +7,7 @@
 
 namespace R2C2 {
 
+class BlockIter;
 class Track;
 
 /**
@@ -24,6 +25,7 @@ public:
 
 	Track *track() const { return _track; }
 	unsigned entry() const { return _entry; }
+	BlockIter block_iter() const;
 	const TrackType::Endpoint &endpoint() const;
 
 private: