/**
 * Copyright 2014 
 * SMEdit https://github.com/StarMade/SMEdit
 * SMTools https://github.com/StarMade/SMTools
 *
 * Licensed 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.
 **/
package jo.util;

import java.awt.Color;
import java.awt.FontMetrics;
import java.awt.Graphics;
import java.io.PrintWriter;
import java.io.StringWriter;
import java.io.UnsupportedEncodingException;
import java.io.Writer;
import java.lang.reflect.Field;
import java.lang.reflect.Modifier;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.HashMap;
import java.util.Map;

/**
 * This is the main string util file. It handles the format of strings such as
 * test, lines, boxes, and other drawn factors in the app.
 *
 * @author Robert Barefoot - version 1.0
 */
public class StringUtil {

    private static final String[] COLOURS_STR = new String[]{"red", "green",
        "cyan", "purple", "white"};
    private static final Map<String, Color> COLOR_MAP = new HashMap<>();

    public static String byteArrayToHexString(final byte[] b) {
        final StringBuilder s = new StringBuilder(b.length * 2);
        for (int i = 0; i < b.length; i++) {
            s.append(Integer.toString((b[i] & 0xff) + 0x100, 16).substring(1));
        }
        return s.toString();
    }

    /**
     * Draws a line on the screen at the specified index. Default is green.
     * <p/>
     * Available colours: red, green, cyan, purple, white.
     *
     * @param render The Graphics object to be used.
     * @param row The index where you want the text.
     * @param text The text you want to render. Colours can be set like [red].
     */
    public static void drawLine(final Graphics render, final int row, final String text) {
        final FontMetrics metrics = render.getFontMetrics();
        final int height = metrics.getHeight() + 4; // height + gap
        final int y = row * height + 15 + 19;
        final String[] texts = text.split("\\[");
        int xIdx = 7;
        Color cur = Color.GREEN;
        for (String t : texts) {
            for (@SuppressWarnings("unused") final String element : COLOURS_STR) {
                // String element = COLOURS_STR[i];
                // Don't search for a starting '[' cause it they don't exists.
                // we split on that.
                final int endIdx = t.indexOf(']');
                if (endIdx != -1) {
                    final String colorName = t.substring(0, endIdx);
                    if (COLOR_MAP.containsKey(colorName)) {
                        cur = COLOR_MAP.get(colorName);
                    } else {
                        try {
                            final Field f = Color.class.getField(colorName);
                            final int mods = f.getModifiers();
                            if (Modifier.isPublic(mods)
                                    && Modifier.isStatic(mods)
                                    && Modifier.isFinal(mods)) {
                                cur = (Color) f.get(null);
                                COLOR_MAP.put(colorName, cur);
                            }
                        } catch (final IllegalAccessException | IllegalArgumentException | NoSuchFieldException | SecurityException ignored) {
                        }
                    }
                    t = t.replace(colorName + "]", "");
                }
            }
            render.setColor(Color.BLACK);
            render.drawString(t, xIdx, y + 1);
            render.setColor(cur);
            render.drawString(t, xIdx, y);
            xIdx += metrics.stringWidth(t);
        }
    }

    public static byte[] getBytesUtf8(final String string) {
        try {
            return string.getBytes("UTF-8");
        } catch (final UnsupportedEncodingException e) {
            throw new IllegalStateException(e);
        }
    }

    public static String join(final String[] s) {
        final int l = s.length;
        switch (l) {
            case 0:
                return "";
            case 1:
                return s[0];
        }
        final String d = ", ";
        final int x = d.length();
        int n = 0, i;
        for (i = 0; i < l; i++) {
            n += s[i].length() + x;
        }
        final StringBuffer buf = new StringBuffer(n - x);
        i = 0;
        boolean c = true;
        while (c) {
            buf.append(s[i]);
            i++;
            c = i < l;
            if (c) {
                buf.append(d);
            }
        }
        return buf.toString();
    }

    public static String newStringUtf8(final byte[] bytes) {
        if (bytes == null) {
            return null;
        }
        try {
            return new String(bytes, "UTF-8");
        } catch (final UnsupportedEncodingException e) {
            throw new IllegalStateException(e);
        }
    }

    public static String sha1sum(final String data) {
        final MessageDigest md;
        try {
            md = MessageDigest.getInstance("SHA-1");
        } catch (final NoSuchAlgorithmException ignored) {
            return data;
        }
        return byteArrayToHexString(md.digest(getBytesUtf8(data)));
    }

    public static String throwableToString(final Throwable t) {
        if (t != null) {
            final Writer exception = new StringWriter();
            final PrintWriter printWriter = new PrintWriter(exception);
            t.printStackTrace(printWriter);
            return exception.toString();
        }
        return "";
    }

}