#include "Storage.h"
#include "SymbolTable.h"
#include <cmath>
#include <cassert>

Storage::Storage(SymbolTable& tbl)
{
	AddConstants(tbl);
}

void Storage::Clear()
{
	cells_.clear();
	inits_.clear();
}

bool Storage::IsInit(unsigned int id) const
{
	return id < cells_.size() && inits_[id];
}

void Storage::AddConstants(SymbolTable& tbl)
{
	unsigned int id = tbl.Add("e");
	AddValue(id, exp(1.0));

	id = tbl.Add("pi");
	AddValue(id, 2.0*acos(0.0));	//反餘弦 pi = 2*acos(0)
}

double Storage::GetValue(unsigned int id) const
{
	assert (id < cells_.size());
	return cells_[id];
}

void Storage::SetValue(unsigned int id, double val)
{
	assert(id <= cells_.size());
	if (id < cells_.size())
	{
		cells_[id] = val;
		inits_[id] = true; 
	}
	else if (id == cells_.size())
	{
		AddValue(id, val);
	}
}

void Storage::AddValue(unsigned int id, double val)
{
	cells_.resize(id+1);
	inits_.resize(id+1);
	cells_[id] = val;
	inits_[id] = true;
}