// -*- C++ -*-
/* This file is part of
 * ====================================================== 
 * 
 *           LyX, The Document Processor
 * 	 
 *	    Copyright (C) 1997 Asger Alstrup
 *           and the LyX Team.
 *
 * ====================================================== */

#include <config.h>
#include <cmath>	// fabs()
#include <cstdlib>	// atoi()

#ifdef __GNUG__
#pragma implementation "FontInfo.h"
#endif

#include "FontInfo.h"
#include "debug.h"
#include "lyxrc.h"	// lyxrc.use_scalable_fonts
#include "support/lstrings.h"

extern LyXRC * lyxrc;

/// Load font close to this size
string FontInfo::getFontname(int size)
{
	if (!exist())
		return string();

	int closestind = -1;
	double error = 100000;

	for (int i = 0; i<matches; i++) {
		if (sizes[i] == 0) {
			// Scalable font should not be considered close
		} else if (sizes[i] == size) {
			lyxerr[Debug::FONT] << "Exact font match with\n"
					    << strings[i] << endl;
			return strings[i];
		} else if (fabs(sizes[i] - size - 0.1) < error) {
			error = fabs(sizes[i] - size - 0.1);
			closestind = i;
		}
	}

	if (scalable && lyxrc->use_scalable_fonts) {
		// We can use scalable
		string font = resize(strings[scaleindex], size);
		lyxerr[Debug::FONT] << "Using scalable font to get\n"
				    << font << endl;
		return font;
	}

	// Did any fonts get close?
	if (closestind == -1) {
		// No, and we are not allowed to use scalables, so...
		return string();
	}

	// We use the closest match
	lyxerr[Debug::FONT] << "Using closest font match to get size "
			    << size 
			    << " with\n" << strings[closestind] << endl;
	return strings[closestind];
}

/// Build newly sized font string 
string FontInfo::resize(string const & font, int size) const {
	// Find the position of the size spec
#ifdef WITH_WARNINGS
#warning rewrite to use std::string constructs
#endif
	int cut = 0, before = 0, after = 0;
	for (string::size_type i = 0; i < font.length(); ++i) {
		if (font[i] == '-') {
			++cut;
			if (cut == 7) {
				before = i;
			} else if (cut == 8) {
				after = i;
				break;
			}
		}
	}

	string head = font;
	head.erase(before + 1, string::npos);
	string tail = font;
	tail.erase(0, after);
	return head + tostr(size) + tail;
}

/// Set new pattern
void FontInfo::setPattern(string const & pat)
{
	release();
	init();
	pattern = pat;
}

/// Query font in X11
void FontInfo::query()
{
	if (queried)
		return;

	if (pattern.empty()) {
		lyxerr << "Can not use empty font name for font query." << endl;
		queried = true;
		return;
	}

	char ** list = XListFonts(fl_display, pattern.c_str(), 100, &matches);

	if (list == 0) {
		// No fonts matched
		scalable = false;
		sizes = 0;
	} else {
		release();
		sizes = new int[matches];
		strings = new string[matches];

		// We have matches. Run them through
		for(int i = 0; i<matches; i++) {
			string name(list[i]);
			sizes[i] = atoi(token(name, '-', 7).c_str());
			strings[i] = name;
			if (sizes[i] == 0) {
				if (scaleindex == -1) {
					scaleindex = i;
				}
				scalable = true;
			};
		};
		XFreeFontNames(list);
	}
	queried = true;
}

/// Release allocated stuff
void FontInfo::release()
{
	if (sizes) {
		delete [] sizes;
		sizes = 0;
	}
	if (strings) {
		delete [] strings;
		strings = 0;
	}
}