#include <fstream.hfa>
#include <string.hfa>
#include <limits.h>										// numeric_limits
#include "config.hfa"

static void comments( ifstream & in, string & name ) {
	for () {
		in | name;
	  if ( name(0,1) != "#" ) break;
		in | nl;										// ignore remainder of line
	} // for
} // comments

// Process the configuration file to set the simulation parameters.
void processConfigFile( const char * configFile, ConfigParms & cparms ) {
	enum { Parmnum = 10 };
	struct {
		const char * name;								// configuration name
		bool used;										// already supplied ?
		unsigned int & value;							// location to put configuration value
	} parms[Parmnum] = {
		{ "SodaCost", false, cparms.sodaCost },
		{ "NumStudents", false, cparms.numStudents },
		{ "MaxPurchases", false, cparms.maxPurchases },
		{ "NumVendingMachines", false, cparms.numVendingMachines },
		{ "MaxStockPerFlavour", false, cparms.maxStockPerFlavour },
		{ "MaxShippedPerFlavour", false, cparms.maxShippedPerFlavour },
		{ "TimeBetweenShipments", false, cparms.timeBetweenShipments },
		{ "GroupoffDelay", false, cparms.groupoffDelay },
		{ "ParentalDelay", false, cparms.parentalDelay },
		{ "NumCouriers", false, cparms.numCouriers },
	};
	string name;
	int value;
	unsigned int posn, numOfParm = 0;

	try {
		ifstream in{ configFile };						// open the configuration file for input

		try {
			for ( cnt; Parmnum ) {						// parameter names can appear in any order
				comments( in, name );					// eof ?
				for ( posn = 0; posn < Parmnum && name != parms[posn].name; posn += 1 ); // linear search
			  if ( posn == Parmnum ) break;				// configuration not found ?
			  if ( parms[posn].used ) break;			// duplicate configuration ?
				in | value;
				if ( value <= 0 ) {
					exit | "Error: file \"" | configFile | "\" parameter " | name | " has value " | value | " which must be positive.";
				} // if
				in | nl;								// ignore remainder of line
				numOfParm += 1;
				parms[posn].used = true;
				parms[posn].value = value;
			} // for
		} catch ( end_of_file * ) {						// end-of-file raised
		} // try

		if ( numOfParm != Parmnum ) {
			serr | "Error: file \"" | configFile | "\" missing configuration parameter(s):";
			for ( unsigned int m = 0; m < Parmnum; m += 1 ) {
				if ( ! parms[m].used ) serr | ' ' | parms[m].name | nonl;
			} // for
			exit | "";									// FIX ME
		} // if

		try {
			comments( in, name );						// ! eof ?
			exit | "Error: file \"" | configFile | "\" has extraneous data: " | name | " ...";
		} catch ( end_of_file * ) {						// end-of-file raised
		} // try
	} catch( open_failure * ) {
		exit | "Error: could not open input file \"" | configFile | "\"";
	} // try
} // processConfigFile