/* This is cvg_qt_util.h
 * This defines some utility functions that use QT structures
 */

#include <limits.h>
#include <stdlib.h>

#include "cvg_qt_util.h"

QString makeAbsolutePath(const QString &Cwd, const QString &Path)
{
	QString retval;
	char resolved[PATH_MAX + 1];
	if (Path.startsWith("/"))
		retval = Path;
	else
		retval = Cwd + Path.right(Path.length() - 2);
	// fix /../ and /./ in the path
	retval = realpath(retval, resolved);
	return retval;
}

QString computeRelativePath(const QString &Base, const QString &Target)
{
//qWarning("cRP(\"" + Base + "\", \"" + Target + "\")");
	// This code kindly supplied by Isaac Richards
	// And then fixed to actually work by me (Matthew Gabeler-Lee)
	if ((Base.isEmpty()) || (Target.isEmpty()))
		return Target;
	const char *a = Base.latin1();
	const char *b = Target.latin1();
	int match_count = 0;
	if ((*a != *b) || (*a != '/'))
		return QString::null;

	a++; b++;

	while (*a == *b)
	{
		if (*a == '/')
			match_count++;
		a++; b++;
	}
//qWarning("cRP: match_count = " + QString::number(match_count));
	// ok, they share the first match_count parent dirs
	// count # of dirs in Base
	int dir_count = 0;
	b = Base.latin1();
	b++;
	while (b)
	{
		b = strchr(b, '/');
		if (b)
		{
			b++;
			dir_count++;
		}
	}
//qWarning("cRP: dir_count = " + QString::number(dir_count));
	// seek to the unshared part of target
	b = Target.latin1();
	b++;
	for (int i = 0; i < match_count; i++)
	{
		b = strchr(b, '/');
		if (!b)
			// BIG FUCKING ERROR
			return QString::null;
		b++;
	}

	// b now points at the non-shared parts of the second path
	QString retval = "";
	for (int j = 0; j < (dir_count - match_count); j++)
		retval += "../";

	retval = "./" + retval + b;

	retval = cleanPath(retval);
	
	return retval;
}

void splitPath(QString &Path, QString &File, const QString &Source)
{
	int slashpos = Source.findRev('/');
	if (slashpos >= 0)
	{
		Path = Source.left(slashpos);
		File = Source.right(Source.length() - slashpos - 1);
	}
	else
	{
		Path = "";
		File = Source;
	}
}

QString cleanPath(QString Path)
{
	// this translates /./ -> / and // -> /
	// works with a local copy of path, so passed by value
	// this is a somewhat inefficient implementation for now, but it
	// works ...
	QString retval;
	while (! Path.isEmpty())
	{
		if (Path.startsWith("//"))
		{
			retval += '/';
			Path.remove(0, 2);
		}
		else if (Path.startsWith("/./"))
		{
			retval += '/';
			Path.remove(0, 3);
		}
		else
		{
			retval += Path[0];
			Path.remove(0, 1);
		}
	}
	return retval;
}