// -*- mode: C++; c-file-style: "cc-mode" -*-
//*************************************************************************
// DESCRIPTION: Verilator: Graph tests
//
// Code available from: http://www.veripool.org/verilator
//
//*************************************************************************
//
// Copyright 2003-2019 by Wilson Snyder.  This program is free software; you can
// redistribute it and/or modify it under the terms of either the GNU
// Lesser General Public License Version 3 or the Perl Artistic License
// Version 2.0.
//
// Verilator 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.
//
//*************************************************************************

#include "config_build.h"
#include "verilatedos.h"

#include "V3Global.h"
#include "V3Graph.h"
#include "V3GraphDfa.h"

#include <cstdarg>

//######################################################################
//######################################################################
// Test class

class V3GraphTest {
public:
    // ***These tests only run with DEBUG ON***
    static int debug() {
	static int level = -1;
	// Note setting just --debug will not enable this, as we exit when we run the test
	if (VL_UNLIKELY(level < 0)) level = v3Global.opt.debugSrcLevel(__FILE__, 0);
	return level;
    }

protected:
    // MEMBERS
    DfaGraph m_graph;

    // METHODS - for children
    virtual void runTest() = 0;	// Run the test
    virtual string name() = 0;	// Name of the test

    // Utilities
    void dump() {
	if (debug()>=9) {
	    m_graph.dumpDotFilePrefixed("v3graphtest_"+name());
	}
    }

public:
    V3GraphTest() {}
    virtual ~V3GraphTest() {}
    void run() {
	if (debug()) runTest();
    }
};

//######################################################################
//######################################################################
// Vertices and nodes

class V3GraphTestVertex : public V3GraphVertex {
    string	m_name;
public:
    V3GraphTestVertex(V3Graph* graphp, const string& name) : V3GraphVertex(graphp), m_name(name) {}
    virtual ~V3GraphTestVertex() {}
    // ACCESSORS
    virtual string name() const { return m_name; }
};

class V3GraphTestVarVertex : public V3GraphTestVertex {
public:
    V3GraphTestVarVertex(V3Graph* graphp, const string& name) : V3GraphTestVertex(graphp, name) {}
    virtual ~V3GraphTestVarVertex() {}
    // ACCESSORS
    virtual string dotColor() const { return "blue"; }
};

//######################################################################
//######################################################################
// Test vertices and nodes

class V3GraphTestStrong : public V3GraphTest {
public:
    virtual string name() { return "strong"; }
    virtual void runTest() {
	V3Graph* gp = &m_graph;
	// Verify we break edges at a good point
	// A simple alg would make 3 breaks, below only requires b->i to break
	V3GraphTestVertex* i	= new V3GraphTestVarVertex(gp,"*INPUTS*");
	V3GraphTestVertex* a	= new V3GraphTestVarVertex(gp,"a");
	V3GraphTestVertex* b	= new V3GraphTestVarVertex(gp,"b");
	V3GraphTestVertex* g1	= new V3GraphTestVarVertex(gp,"g1");
	V3GraphTestVertex* g2	= new V3GraphTestVarVertex(gp,"g2");
	V3GraphTestVertex* g3	= new V3GraphTestVarVertex(gp,"g3");
	V3GraphTestVertex* q	= new V3GraphTestVarVertex(gp,"q");
	new V3GraphEdge(gp, i, a, 2, true);
	new V3GraphEdge(gp, a, b, 2, true);
	new V3GraphEdge(gp, b, g1, 2, true);
	new V3GraphEdge(gp, b, g2, 2, true);
	new V3GraphEdge(gp, b, g3, 2, true);
	new V3GraphEdge(gp, g1, a, 2, true);
	new V3GraphEdge(gp, g3, g2, 2, true);
	new V3GraphEdge(gp, g2, g3, 2, true);
	new V3GraphEdge(gp, g1, q, 2, true);
	new V3GraphEdge(gp, g2, q, 2, true);
	new V3GraphEdge(gp, g3, q, 2, true);

	gp->stronglyConnected(&V3GraphEdge::followAlwaysTrue);
	dump();

        UASSERT(i->color()!=a->color() && a->color() != g2->color() && g2->color() != q->color(),
                "SelfTest: Separate colors not assigned");
        UASSERT(a->color()==b->color() && a->color()==g1->color(),
                "SelfTest: Strongly connected nodes not colored together");
        UASSERT(g2->color()==g3->color(),
                "SelfTest: Strongly connected nodes not colored together");
    }
};

class V3GraphTestAcyc : public V3GraphTest {
public:
    virtual string name() { return "acyc"; }
    virtual void runTest() {
	V3Graph* gp = &m_graph;
	// Verify we break edges at a good point
	// A simple alg would make 3 breaks, below only requires b->i to break
	V3GraphTestVertex* i	= new V3GraphTestVarVertex(gp,"*INPUTS*");
	V3GraphTestVertex* a	= new V3GraphTestVarVertex(gp,"a");
	V3GraphTestVertex* b	= new V3GraphTestVarVertex(gp,"b");
	V3GraphTestVertex* g1	= new V3GraphTestVarVertex(gp,"g1");
	V3GraphTestVertex* g2	= new V3GraphTestVarVertex(gp,"g2");
	V3GraphTestVertex* g3	= new V3GraphTestVarVertex(gp,"g3");
	new V3GraphEdge(gp, i, a, 2, true);
	new V3GraphEdge(gp, a, b, 2, true);
	new V3GraphEdge(gp, b, g1, 2, true);
	new V3GraphEdge(gp, b, g2, 2, true);
	new V3GraphEdge(gp, b, g3, 2, true);
	new V3GraphEdge(gp, g1, a, 2, true);
	new V3GraphEdge(gp, g2, a, 2, true);
	new V3GraphEdge(gp, g3, a, 2, true);

	gp->acyclic(&V3GraphEdge::followAlwaysTrue);
	gp->order();
	dump();
    }
};

class V3GraphTestVars : public V3GraphTest {
public:
    virtual string name() { return "vars"; }
    virtual void runTest() {
	V3Graph* gp = &m_graph;

	V3GraphTestVertex* clk	= new V3GraphTestVarVertex(gp,"$clk");

	V3GraphTestVertex* a	= new V3GraphTestVarVertex(gp,"$a");
	V3GraphTestVertex* a_dly	= new V3GraphTestVarVertex(gp,"$a_dly");
	V3GraphTestVertex* a_dlyblk= new V3GraphTestVarVertex(gp,"$a_dlyblk");
	V3GraphTestVertex* b	= new V3GraphTestVarVertex(gp,"$b");
	V3GraphTestVertex* b_dly	= new V3GraphTestVarVertex(gp,"$b_dly");
	V3GraphTestVertex* b_dlyblk= new V3GraphTestVarVertex(gp,"$b_dlyblk");
	V3GraphTestVertex* c	= new V3GraphTestVarVertex(gp,"$c");
	V3GraphTestVertex* i	= new V3GraphTestVarVertex(gp,"$i");

	V3GraphTestVertex* ap	= new V3GraphTestVarVertex(gp,"$a_pre");
	V3GraphTestVertex* bp	= new V3GraphTestVarVertex(gp,"$b_pre");
	V3GraphTestVertex* cp	= new V3GraphTestVarVertex(gp,"$c_pre");

	V3GraphTestVertex* n;

	// Logical order between clk, and posedge blocks
	//   implemented by special CLK prod/cons?
	// Required order between first x_DLY<=x_pre and final x<=x_DLY
	//   implemented by producer/consumer on a_dly signals
	// Required order between first x_DLY<=x_pre and x_DLY<=setters
	//   implemented by fake dependency on _dlyblk
	// Required order between x_DLY<=setters and final x<=x_DLY
	//   implemented by producer/consumer on a_dly signals
	// Desired order between different _DLY blocks so we can elim temporaries
	//   implemented by cutable "pre" signal dependencies


	n = new V3GraphTestVertex(gp,"*INPUTS*"); {
	    new V3GraphEdge(gp, n, clk, 2);
	    new V3GraphEdge(gp, n, i, 2);
	}

	V3GraphTestVertex* posedge = n = new V3GraphTestVertex(gp,"*posedge clk*"); {
	    new V3GraphEdge(gp, clk, n, 2);
	}

	// AssignPre's     VarRefs on LHS:  generate special BLK
	//    normal:      VarRefs on LHS:  generate normal
	//    underSBlock: VarRefs on RHS:  consume 'pre' (required to save cutable tests)
	n = new V3GraphTestVertex(gp,"a_dly<PRE=a"); {
	    new V3GraphEdge(gp, n, a_dlyblk, 2);  // Block ordering
	    new V3GraphEdge(gp, n, a_dly, 2);
	    new V3GraphEdge(gp, ap, n, 2, true);   // DESIRED delayed ordering (inp is required)
	    new V3GraphEdge(gp, posedge, n, 2);
	}
	n = new V3GraphTestVertex(gp,"b_dly<PRE=b"); {
	    new V3GraphEdge(gp, n, b_dlyblk, 2);  // Block ordering
	    new V3GraphEdge(gp, n, b_dly, 2);
	    new V3GraphEdge(gp, bp, n, 2, true);   // DESIRED delayed ordering
	    new V3GraphEdge(gp, posedge, n, 2);
	}

	// AssignDly's     VarRefs on LHS:  consume special BLK
	//    normal:      VarRefs on LHS:  generate normal
	//    underSBlock: VarRefs on RHS:  generate 'pre' signals (cutable)
	//    SenItems:    consume CLOCK dependency
	n = new V3GraphTestVertex(gp,"a_dly<=b|c"); {
	    new V3GraphEdge(gp, a_dlyblk, n, 2);  // Block ordering in
	    new V3GraphEdge(gp, n, a_dly, 2);
	    // Note we don't include ap as we're generating a_dly
	    new V3GraphEdge(gp, n, bp, 2);   // DESIRED delayed usage
	    new V3GraphEdge(gp, n, cp, 2);   // DESIRED delayed usage
	    new V3GraphEdge(gp, posedge, n, 2);
	}
	n = new V3GraphTestVertex(gp,"b_dly<=a"); {
	    new V3GraphEdge(gp, b_dlyblk, n, 2);  // Block ordering in
	    new V3GraphEdge(gp, n, b_dly, 2);
	    new V3GraphEdge(gp, n, ap, 2);   // DESIRED delayed usage
	    new V3GraphEdge(gp, posedge, n, 2);
	}

	// AssignPost's
	//    normal:      VarRefs on LHS:  generate normal
	//    underSBlock: VarRefs on RHS:  consume normal
	n = new V3GraphTestVertex(gp,"a=POST=a_dly"); {
	    new V3GraphEdge(gp, n, a, 3);
	    new V3GraphEdge(gp, a_dly, n, 3);
	    new V3GraphEdge(gp, posedge, n, 2);
	}
	n = new V3GraphTestVertex(gp,"b=POST=b_dly"); {
	    new V3GraphEdge(gp, n, b, 3);
	    new V3GraphEdge(gp, b_dly, n, 3);
	    new V3GraphEdge(gp, posedge, n, 2);
	}

	// COMBO
	// Inbound edges are always uncutable, because we must put combo logic after sequential
	// Outbound are cutable, as we may need to evaluate multiple times

	{
	    n = new V3GraphTestVertex(gp,"c=a|b|i");
	    new V3GraphEdge(gp, n, c, 1, true);
	    new V3GraphEdge(gp, a, n, 1, false);
	    new V3GraphEdge(gp, b, n, 1, false);
	    new V3GraphEdge(gp, i, n, 1, false);
	}

	gp->acyclic(&V3GraphEdge::followAlwaysTrue);
	gp->order();

	dump();
    }
};

//======================================================================

class DfaTestVertex : public DfaVertex {
    string	m_name;
public:
    DfaTestVertex(DfaGraph* graphp, const string& name) : DfaVertex(graphp), m_name(name) {}
    virtual ~DfaTestVertex() {}
    // ACCESSORS
    virtual string name() const { return m_name; }
};

class V3GraphTestDfa : public V3GraphTest {

public:
    virtual string name() { return "dfa"; }
    virtual void runTest() {
	DfaGraph* gp = &m_graph;

	// NFA Pattern for ( (LR) | (L*R)) Z
	DfaTestVertex*  st  = new DfaTestVertex(gp,"*START*");  st->start(true);
	DfaTestVertex*  sl  = new DfaTestVertex(gp,"sL");
	DfaTestVertex*  srs = new DfaTestVertex(gp,"sR*");
	DfaTestVertex*  sls = new DfaTestVertex(gp,"sL*");
	DfaTestVertex*  sr  = new DfaTestVertex(gp,"sR");
	DfaTestVertex*  sz  = new DfaTestVertex(gp,"sZ");
	DfaTestVertex*  sac = new DfaTestVertex(gp,"*ACCEPT*");  sac->accepting(true);

	VNUser L = VNUser::fromInt(0xaa);
	VNUser R = VNUser::fromInt(0xbb);
	VNUser Z = VNUser::fromInt(0xcc);

	new DfaEdge(gp, st,  sl,  DfaEdge::EPSILON());
	new DfaEdge(gp, sl,  srs, L);
	new DfaEdge(gp, srs, srs, R);
	new DfaEdge(gp, srs, sz,  Z);
	new DfaEdge(gp, sz,  sac, DfaEdge::EPSILON());

	new DfaEdge(gp, st,  sls, DfaEdge::EPSILON());
	new DfaEdge(gp, sls, sls, L);
	new DfaEdge(gp, sls, sr,  R);
	new DfaEdge(gp, sr,  sz,  Z);
	new DfaEdge(gp, sz,  sac, DfaEdge::EPSILON());

	dump();
	gp->nfaToDfa();
	dump();
	gp->dfaReduce();
	dump();

	gp->dfaComplement();
	dump();
	gp->dfaReduce();
	dump();
    }
};

//======================================================================

class V3GraphTestImport : public V3GraphTest {

    // cppcheck-suppress functionConst
    void dotImport();

public:
    virtual string name() { return "import"; }
    virtual void runTest() {
	DfaGraph* gp = &m_graph;
        if (V3GraphTest::debug()) DfaGraph::debug(9);
	dotImport();
	dump();
	gp->acyclic(&V3GraphEdge::followAlwaysTrue);
	dump();
	gp->rank(&V3GraphEdge::followAlwaysTrue);
	dump();
    }
};

#if 0
# include "graph_export.cpp"
#else
void V3GraphTestImport::dotImport() {
}
#endif

//======================================================================

void V3Graph::selfTest() {
    // Execute all of the tests
    UINFO(2,__FUNCTION__<<": "<<endl);
    { V3GraphTestStrong test; test.run(); }
    { V3GraphTestAcyc test; test.run(); }
    { V3GraphTestVars test; test.run(); }
    { V3GraphTestDfa test; test.run(); }
    { V3GraphTestImport test; test.run(); }
    if (V3GraphTest::debug()) v3fatalSrc("Exiting due to graph testing enabled");
}
