/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/* $Id: RasterFont.java 1761019 2016-09-16 10:43:45Z ssteiner $ */

package org.apache.fop.afp.fonts;

import java.awt.Rectangle;
import java.util.HashMap;
import java.util.Map;
import java.util.SortedMap;
import java.util.TreeMap;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

A font where each character is stored as an array of pixels (a bitmap). Such
fonts are not easily scalable, in contrast to vectored fonts. With this type
of font, the font metrics information is held in character set files (one for
each size and style).
/**
 * A font where each character is stored as an array of pixels (a bitmap). Such
 * fonts are not easily scalable, in contrast to vectored fonts. With this type
 * of font, the font metrics information is held in character set files (one for
 * each size and style).
 */
public class RasterFont extends AFPFont {

    
Static logging instance /** Static logging instance */
    protected static final Log LOG = LogFactory.getLog("org.apache.fop.afp.fonts");

    private final SortedMap<Integer, CharacterSet> charSets = new TreeMap<Integer, CharacterSet>();
    private Map<Integer, CharacterSet> substitutionCharSets;

    private CharacterSet charSet;

    
Constructor for the raster font requires the name, weight and style
attribute to be available as this forms the key to the font.
Params:
name – the name of the font
embeddable – true if the font is embeddable/**
     * Constructor for the raster font requires the name, weight and style
     * attribute to be available as this forms the key to the font.
     *
     * @param name the name of the font
     * @param embeddable {@code true} if the font is embeddable
     */
    public RasterFont(String name, boolean embeddable) {
        super(name, embeddable);
    }

    
Adds the character set for the given point size
Params:
size – point size (in mpt)
characterSet – character set/**
     * Adds the character set for the given point size
     * @param size point size (in mpt)
     * @param characterSet character set
     */
    public void addCharacterSet(int size, CharacterSet characterSet) {
        //TODO: replace with Integer.valueOf() once we switch to Java 5
        this.charSets.put(size, characterSet);
        this.charSet = characterSet;
    }

    
Get the character set metrics for the specified point size.
Params:
sizeInMpt – the point size (in mpt)
Returns:
the character set metrics/**
     * Get the character set metrics for the specified point size.
     *
     * @param sizeInMpt the point size (in mpt)
     * @return the character set metrics
     */
    public CharacterSet getCharacterSet(int sizeInMpt) {

        Integer requestedSize = sizeInMpt;
        CharacterSet csm = charSets.get(requestedSize);
        double sizeInPt = sizeInMpt / 1000.0;

        if (csm != null) {
            return csm;
        }

        if (substitutionCharSets != null) {
            //Check first if a substitution has already been added
            csm = substitutionCharSets.get(requestedSize);
        }

        if (csm == null && !charSets.isEmpty()) {
            // No match or substitution found, but there exist entries
            // for other sizes
            // Get char set with nearest, smallest font size
            SortedMap<Integer, CharacterSet> smallerSizes = charSets.headMap(requestedSize);
            SortedMap<Integer, CharacterSet> largerSizes = charSets.tailMap(requestedSize);
            int smallerSize = smallerSizes.isEmpty() ? 0
                    : smallerSizes.lastKey();
            int largerSize = largerSizes.isEmpty() ? Integer.MAX_VALUE
                    : largerSizes.firstKey();

            Integer fontSize;
            if (!smallerSizes.isEmpty()
                            && (sizeInMpt - smallerSize) <= (largerSize - sizeInMpt)) {
                fontSize = smallerSize;
            } else {
                fontSize = largerSize;
            }
            csm = charSets.get(fontSize);

            if (csm != null) {
                // Add the substitute mapping, so subsequent calls will
                // find it immediately
                if (substitutionCharSets == null) {
                    substitutionCharSets = new HashMap<Integer, CharacterSet>();
                }
                substitutionCharSets.put(requestedSize, csm);
                // do not output the warning if the font size is closer to an integer less than 0.1
                if (!(Math.abs(fontSize / 1000.0 - sizeInPt) < 0.1)) {
                    String msg = "No " + sizeInPt + "pt font " + getFontName()
                            + " found, substituted with " + fontSize / 1000f + "pt font";
                    LOG.warn(msg);
                }
            }
        }

        if (csm == null) {
            // Still no match -> error
            String msg = "No font found for font " + getFontName() + " with point size " + sizeInPt;
            LOG.error(msg);
            throw new FontRuntimeException(msg);
        }

        return csm;

    }

    private int metricsToAbsoluteSize(CharacterSet cs, int value, int givenSize) {
        int nominalVerticalSize = cs.getNominalVerticalSize();
        if (nominalVerticalSize != 0) {
            return value * nominalVerticalSize;
        } else {
            return value * givenSize;
        }
    }

    private int metricsToAbsoluteSize(CharacterSet cs, double value, int givenSize) {
        int nominalVerticalSize = cs.getNominalVerticalSize();
        if (nominalVerticalSize != 0) {
            return (int) (value * nominalVerticalSize);
        } else {
            return (int) (value * givenSize);
        }
    }

    
The ascender is the part of a lowercase letter that extends above the
"x-height" (the height of the letter "x"), such as "d", "t", or "h". Also
used to denote the part of the letter extending above the x-height.
Params:
size – the font size (in mpt)
Returns:
the ascender for the given point size/**
     * The ascender is the part of a lowercase letter that extends above the
     * "x-height" (the height of the letter "x"), such as "d", "t", or "h". Also
     * used to denote the part of the letter extending above the x-height.
     *
     * @param size the font size (in mpt)
     * @return the ascender for the given point size
     */
    public int getAscender(int size) {
        CharacterSet cs = getCharacterSet(size);
        return metricsToAbsoluteSize(cs, cs.getAscender(), size);
    }

    
{@inheritDoc} /** {@inheritDoc} */
    public int getUnderlinePosition(int size) {
        CharacterSet cs = getCharacterSet(size);
        return metricsToAbsoluteSize(cs, cs.getUnderscorePosition(), size);
    }

    @Override
    public int getUnderlineThickness(int size) {
        CharacterSet cs = getCharacterSet(size);
        int underscoreWidth = cs.getUnderscoreWidth();
        return underscoreWidth == 0 ? super.getUnderlineThickness(size)
                : metricsToAbsoluteSize(cs, underscoreWidth, size);
    }

    
Obtains the height of capital letters for the specified point size.
Params:
size – the font size (in mpt)
Returns:
the cap height for the specified point size/**
     * Obtains the height of capital letters for the specified point size.
     *
     * @param size the font size (in mpt)
     * @return the cap height for the specified point size
     */
    public int getCapHeight(int size) {
        CharacterSet cs = getCharacterSet(size);
        return metricsToAbsoluteSize(cs, cs.getCapHeight(), size);
    }

    
The descender is the part of a lowercase letter that extends below the
base line, such as "g", "j", or "p". Also used to denote the part of the
letter extending below the base line.
Params:
size – the font size (in mpt)
Returns:
the descender for the specified point size/**
     * The descender is the part of a lowercase letter that extends below the
     * base line, such as "g", "j", or "p". Also used to denote the part of the
     * letter extending below the base line.
     *
     * @param size the font size (in mpt)
     * @return the descender for the specified point size
     */
    public int getDescender(int size) {
        CharacterSet cs = getCharacterSet(size);
        return metricsToAbsoluteSize(cs, cs.getDescender(), size);
    }

    
The "x-height" (the height of the letter "x").
Params:
size – the font size (in mpt)
Returns:
the x height for the given point size/**
     * The "x-height" (the height of the letter "x").
     *
     * @param size the font size (in mpt)
     * @return the x height for the given point size
     */
    public int getXHeight(int size) {
        CharacterSet cs = getCharacterSet(size);
        return metricsToAbsoluteSize(cs, cs.getXHeight(), size);
    }

    
Obtain the width of the character for the specified point size.
Params:
character – the character
size – the font size (in mpt)
Returns:
the width for the given point size/**
     * Obtain the width of the character for the specified point size.
     * @param character the character
     * @param size the font size (in mpt)
     * @return the width for the given point size
     */
    public int getWidth(int character, int size) {
        CharacterSet cs = getCharacterSet(size);
        return metricsToAbsoluteSize(cs, cs.getWidth(toUnicodeCodepoint(character), 1), size);
    }

    
TODO
/**
     * TODO
     */
    public Rectangle getBoundingBox(int character, int size) {
        CharacterSet cs = getCharacterSet(size);
        Rectangle characterBox = cs.getCharacterBox(toUnicodeCodepoint(character), 1);
        int x = metricsToAbsoluteSize(cs, characterBox.getX(), size);
        int y = metricsToAbsoluteSize(cs, characterBox.getY(), size);
        int w = metricsToAbsoluteSize(cs, characterBox.getWidth(), size);
        int h = metricsToAbsoluteSize(cs, characterBox.getHeight(), size);
        return new Rectangle(x, y, w, h);
    }

    
{@inheritDoc} /** {@inheritDoc} */
    public boolean hasChar(char c) {
        return charSet.hasChar(c);
    }

    
Map a Unicode character to a code point in the font.
Params:
c – character to map
Returns:
the mapped character/**
     * Map a Unicode character to a code point in the font.
     * @param c character to map
     * @return the mapped character
     */
    public char mapChar(char c) {
        return charSet.mapChar(c);
    }

    
{@inheritDoc} /** {@inheritDoc} */
    public String getEncodingName() {
        return charSet.getEncoding();
    }
}