/home/marsyas/marsyas/src/marsyas/Expr.cpp

/*
** Copyright (C) 1998-2007 George Tzanetakis <gtzan@cs.uvic.ca>
**  
** This program 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 2 of the License, or
** (at your option) any later version.
** 
** This program 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 this program; if not, write to the Free Software 
** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include "Expr.h"
#include "ExParser.h"
#include "ExScanner.h"
#include "ExSymTbl.h"
#include "ExNode.h"
#include "MarSystem.h"
#include "Scheduler.h"
#include "TmTimer.h"

#include <fstream>

using std::ostringstream;
using namespace Marsyas;

void
Ex::parse(Expr* e, ExNode*& init, ExNode*& expr)
{
    ExScanner s;
    ExParser p(&(e->timer_),&s);

    // parse init expression
    if (init_!="") {
        s.setString(init_.c_str());
        p.Parse(e->sched_,e->marsym_,e->symbol_table_);
        init=p.getTree();
    }
    else init=NULL;

    if (expr_!="") {
            s.setString(expr_.c_str());
            p.Parse(e->sched_,e->marsym_,e->symbol_table_);
            expr=p.getTree();
    }
    else expr=NULL;
}

Expr::Expr()
{
    symbol_table_=NULL;
    init_expr_=NULL; expr_=NULL;
    rept_=NULL; rate_=NULL;
    marsym_=NULL;
    sched_=NULL;
    timer_=NULL;
    initialized_=false;
}
Expr::Expr(MarSystem* msym, Ex e)
{
    marsym_=msym;
    timer_=NULL;
    sched_=NULL;
    symbol_table_=new ExRecord();
    symbol_table_->inc_ref();
    e.parse(this,init_expr_,expr_);
    rept_=NULL;
    rate_=NULL;
    initialized_=false;
}
Expr::Expr(MarSystem* msym, Ex e, Rp r)
{
    set(msym,e,r);
}
Expr::Expr(MarSystem* msym, ExFile ef)
{
    Ex e=ef.getEx();
    Rp r=ef.getRp();
    set(msym,e,r);
}
void
Expr::set(MarSystem* m, Ex& e, Rp& r)
{
    marsym_=m;
    timer_=NULL;
    sched_=NULL;
    symbol_table_=new ExRecord();
    symbol_table_->inc_ref();
    e.parse(this,init_expr_,expr_);
    r.parse(this,rept_,rate_);
    if (rept_&&rept_->getEvalType()!="mrs_bool") {
        MRSWARN("Expr::  Repetition expression must evaluate to bool: "+rept_->getEvalType());
        rept_->deref(); rept_=NULL;
        if (rate_) rate_->deref(); rate_=NULL;
    }
    else if (rate_&&rate_->getEvalType()!="mrs_string") {
        MRSWARN("Expr::  Repetition rate expression must evaluate to string: "+rate_->getEvalType());
        if (rept_) rept_->deref(); rept_=NULL;
        if (rate_) rate_->deref(); rate_=NULL;
    }
    initialized_=false;
}

Expr::~Expr()
{
    symbol_table_->deref();
    delete expr_;
    delete init_expr_;
    delete rept_;
    delete rate_;
}

void
Expr::eval()
{
    if (expr_!=NULL)
        expr_->eval();
}

bool
Expr::repeat()
{
    return (rept_)&&(rept_->eval()).toBool();
}

std::string
Expr::repeat_interval()
{
    if (rate_) return (rate_->eval()).toString();
    return "__NULL";
}

void
Expr::setScheduler(Scheduler* v)
{
    sched_=v;
}

void
Expr::setTimer(TmTimer* t)
{
    timer_=t;
}

void
Expr::post()
{
    if (init_expr_&&!initialized_)
        init_expr_->eval();
    initialized_=true;
}

void
ExFile::read(std::string fname)
{
    std::ifstream from(fname.c_str());
    if (!from) { MRSWARN("ExFile::read  Cannot open file: "+fname); return; }
    std::string data;
    char buffer[256];
    // flags correspond to the 5 possible blocks, no block can be declared more than once
    bool flags[6] = { false };
    int pos=-1;
    std::string line;
    while (from.getline(buffer,256)) {
        if (buffer[0]=='#') {
            if (buffer[1]=='E'&&buffer[2]=='x') { // #ExInit: | #ExExpr:
                if (buffer[3]=='I'&&buffer[4]=='n'&&buffer[5]=='i'&&buffer[6]=='t'&&buffer[7]==':') {
                    store(pos,data); data=""; pos=1;
                    if (flags[pos]) { MRSWARN("ExFile::read  Double declaration of #ExInit: block"); }
                }
                else if (buffer[3]=='E'&&buffer[4]=='x'&&buffer[5]=='p'&&buffer[6]=='r'&&buffer[7]==':') {
                    store(pos,data); data=""; pos=2;
                    if (flags[pos]) { MRSWARN("ExFile::read  Double declaration of #ExExpr: block"); }
                }
            }
            else if (buffer[1]=='R'&&buffer[2]=='p') {
                if (buffer[3]=='E'&&buffer[4]=='x'&&buffer[5]=='p'&&buffer[6]=='r'&&buffer[7]==':') {
                    // #RpExpr:
                    store(pos,data); data=""; pos=3;
                    if (flags[pos]) { MRSWARN("ExFile::read  Double declaration of #RpExpr: block"); }
                }
                else if (buffer[3]=='R'&&buffer[4]=='a'&&buffer[5]=='t'&&buffer[6]=='e'&&buffer[7]==':') {
                    // #RpRate:
                    store(pos,data); data=""; pos=4;
                    if (flags[pos]) { MRSWARN("ExFile::read  Double declaration of #RpRate: block"); }
                }
            }
            else {
                MRSWARN("ExFile::read  Unknown macro # in ExFile");
            }
            flags[pos]=true;
        }
        else { data=data+buffer; }
    }
    if (!data.empty()) { store(pos,data); }
    from.close();
    file_read_=true;
}

void
ExFile::store(int pos, std::string data)
{
    switch(pos) {
        case 1: iex_=data; break;
        case 2: ex_=data; break;
        case 3: rp_=data; break;
        case 4: rr_=data; break;
    }
}

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