// SortUpdates.cpp - SORT UPDATE ENTRIES BY FILE NAME
//
// MAINTENANCE HISTORY
// DATE		PROGRAMMER AND DETAILS
// 24-08-07	JS	Original
//
//-----------------------------------------------------------------------------

#include <cstdlib>		// C-style standard library
#include <string>		// C++ string declarations
#include <iostream>		// C++ I/O stream declarations
#include <fstream>		// C++ file stream declarations
#include <vector>		// C++ vector declarations
#include <algorithm>		// C++ algorithms
using namespace std;		// Expand the standard namespace

//-----------------------------------------------------------------------------

// UPDATE STRUCTURE

struct Update_t {
	string		updateName;	// Updated file name
	int		updateRelease;	// Release number
	int		updateLevel;	// Level number
	string		updateData;	// Update data

	// Compare Updates

	bool
	operator < (
		const Update_t &update)	// Value to compare
	const
	{
		if (updateName < update.updateName) return 1;
		if (updateName > update.updateName) return 0;
		if (updateRelease < update.updateRelease) return 1;
		if (updateRelease > update.updateRelease) return 0;
		return updateLevel < update.updateLevel;
	}
};

//-----------------------------------------------------------------------------

// UPDATE VECTOR TYPE DEFINITION

typedef vector<Update_t> UpdateVec_t;

//-----------------------------------------------------------------------------

// MAIN LINE

int
main (
	int		argc,		// Argument count
	char		*argv[])	// Argument value pointers
{
	ifstream	ifs;		// Input file stream
	Update_t	updateRec;	// Update record
	UpdateVec_t	updateVec;	// Update vector
	string		line;		// Input line
	int		j;		// General purpose index
	size_t		i;		// General purpose index

	// Read the updates from the various files

	for (j = 1; j < argc; j++) {

		// Open the file

		ifs.clear();
		ifs.open (argv[j]);
		if ( ! ifs) {
			cerr << "Error: cannot open " << argv[j] << '\n';
			exit (1);
		}

		// Process the lines in the input file

		getline (ifs, line);
		while (line[0] == '=') {

			// Interpret a header line

			i = 0;
			while (line[i] == '=') i ++ ;
			while (line[i] == ' ') i ++ ;
			updateRec.updateName = "";
			do {
				updateRec.updateName += line[i];
				i ++ ;
			} while (line[i] != ' ' && line[i] != '\0');
			while (line[i] == ' ') i ++ ;
			updateRec.updateRelease = 0;
			if ( ! isdigit(line[i])) {
				cerr << "Error: header format error\n";
				exit (1);
			}
			do {
				updateRec.updateRelease =
					updateRec.updateRelease * 10
						+ line[i] - '0';
				i ++ ;
			} while (isdigit(line[i]));
			if (line[i] != '.') {
				cerr << "Error: header format error\n";
				exit (1);
			}
			i ++ ;
			updateRec.updateLevel = 0;
			if ( ! isdigit(line[i])) {
				cerr << "Error: header format error\n";
				exit (1);
			}
			do {
				updateRec.updateLevel =
					updateRec.updateLevel * 10
						+ line[i] - '0';
				i ++ ;
			} while (isdigit(line[i]));
			while (line[i] == ' ') i ++ ;
			if (line[i] != '=') {
				cerr << "Error: header format error\n";
				exit (1);
			}

			// Load the header and change lines into updateData

			updateRec.updateData = "";
			do {
				updateRec.updateData += line + '\n';
				getline (ifs, line);
			} while (line[0] != '=' && line[0] != '\0');
			updateVec.push_back (updateRec);
		}

		// Check for files that do not start with a header line

		if ( ! ifs.eof()) {
			cerr << "Error: data format error\n";
			exit (1);
		}

		// Close the change listing

		ifs.close();
	}

	// Sort the changes in the required order

	sort (updateVec.begin(), updateVec.end());

	// Emit the changes

	for (i = 0; i < updateVec.size(); i++)
		cout << updateVec[i].updateData;

	return 0;
}