/*
 * $Id: BaseField.java 4784 2011-03-15 08:33:00Z blowagie $
 *
 * This file is part of the iText (R) project.
 * Copyright (c) 1998-2011 1T3XT BVBA
 * Authors: Bruno Lowagie, Paulo Soares, et al.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License version 3
 * as published by the Free Software Foundation with the addition of the
 * following permission added to Section 15 as permitted in Section 7(a):
 * FOR ANY PART OF THE COVERED WORK IN WHICH THE COPYRIGHT IS OWNED BY 1T3XT,
 * 1T3XT DISCLAIMS THE WARRANTY OF NON INFRINGEMENT OF THIRD PARTY RIGHTS.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU Affero General Public License for more details.
 * You should have received a copy of the GNU Affero General Public License
 * along with this program; if not, see http://www.gnu.org/licenses or write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA, 02110-1301 USA, or download the license from the following URL:
 * http://itextpdf.com/terms-of-use/
 *
 * The interactive user interfaces in modified source and object code versions
 * of this program must display Appropriate Legal Notices, as required under
 * Section 5 of the GNU Affero General Public License.
 *
 * In accordance with Section 7(b) of the GNU Affero General Public License,
 * a covered work must retain the producer line in every PDF that is created
 * or manipulated using iText.
 *
 * You can be released from the requirements of the license by purchasing
 * a commercial license. Buying such a license is mandatory as soon as you
 * develop commercial activities involving the iText software without
 * disclosing the source code of your own applications.
 * These activities include: offering paid services to customers as an ASP,
 * serving PDFs on the fly in a web application, shipping iText with a closed
 * source product.
 *
 * For more information, please contact iText Software Corp. at this
 * address: sales@itextpdf.com
 */
package com.itextpdf.text.pdf;

import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;

import com.itextpdf.text.BaseColor;
import com.itextpdf.text.DocumentException;
import com.itextpdf.text.Element;
import com.itextpdf.text.Rectangle;
import com.itextpdf.text.error_messages.MessageLocalization;

/** Common field variables.
 * @author Paulo Soares
 */
public abstract class BaseField {

    /** A thin border with 1 point width. */
    public static final float BORDER_WIDTH_THIN = 1;
    /** A medium border with 2 point width. */
    public static final float BORDER_WIDTH_MEDIUM = 2;
    /** A thick border with 3 point width. */
    public static final float BORDER_WIDTH_THICK = 3;
    /** The field is visible. */
    public static final int VISIBLE = 0;
    /** The field is hidden. */
    public static final int HIDDEN = 1;
    /** The field is visible but does not print. */
    public static final int VISIBLE_BUT_DOES_NOT_PRINT = 2;
    /** The field is hidden but is printable. */
    public static final int HIDDEN_BUT_PRINTABLE = 3;
    /** The user may not change the value of the field. */
    public static final int READ_ONLY = PdfFormField.FF_READ_ONLY;
    /** The field must have a value at the time it is exported by a submit-form
     * action.
     */
    public static final int REQUIRED = PdfFormField.FF_REQUIRED;
    /** The field may contain multiple lines of text.
     * This flag is only meaningful with text fields.
     */
    public static final int MULTILINE = PdfFormField.FF_MULTILINE;
    /** The field will not scroll (horizontally for single-line
     * fields, vertically for multiple-line fields) to accommodate more text
     * than will fit within its annotation rectangle. Once the field is full, no
     * further text will be accepted.
     */
    public static final int DO_NOT_SCROLL = PdfFormField.FF_DONOTSCROLL;
    /** The field is intended for entering a secure password that should
     * not be echoed visibly to the screen.
     */
    public static final int PASSWORD = PdfFormField.FF_PASSWORD;
    /** The text entered in the field represents the pathname of
     * a file whose contents are to be submitted as the value of the field.
     */
    public static final int FILE_SELECTION = PdfFormField.FF_FILESELECT;
    /** The text entered in the field will not be spell-checked.
     * This flag is meaningful only in text fields and in combo
     * fields with the <CODE>EDIT</CODE> flag set.
     */
    public static final int DO_NOT_SPELL_CHECK = PdfFormField.FF_DONOTSPELLCHECK;
    /** If set the combo box includes an editable text box as well as a drop list; if
     * clear, it includes only a drop list.
     * This flag is only meaningful with combo fields.
     */
    public static final int EDIT = PdfFormField.FF_EDIT;

    /** whether or not a list may have multiple selections.  Only applies to /CH LIST
     * fields, not combo boxes.
     */
    public static final int MULTISELECT = PdfFormField.FF_MULTISELECT;

    /**
     * combo box flag.
     */
    public static final int COMB = PdfFormField.FF_COMB;

    protected float borderWidth = BORDER_WIDTH_THIN;
    protected int borderStyle = PdfBorderDictionary.STYLE_SOLID;
    protected BaseColor borderColor;
    protected BaseColor backgroundColor;
    protected BaseColor textColor;
    protected BaseFont font;
    protected float fontSize = 0;
    protected int alignment = Element.ALIGN_LEFT;
    protected PdfWriter writer;
    protected String text;
    protected Rectangle box;

    /** Holds value of property rotation. */
    protected int rotation = 0;

    /** Holds value of property visibility. */
    protected int visibility;

    /** Holds value of property fieldName. */
    protected String fieldName;

    /** Holds value of property options. */
    protected int options;

    /** Holds value of property maxCharacterLength. */
    protected int maxCharacterLength;

    private final static HashMap<PdfName, Integer> fieldKeys = new HashMap<PdfName, Integer>();

    static {
        fieldKeys.putAll(PdfCopyFieldsImp.fieldKeys);
        fieldKeys.put(PdfName.T, Integer.valueOf(1));
    }
    /** Creates a new <CODE>TextField</CODE>.
     * @param writer the document <CODE>PdfWriter</CODE>
     * @param box the field location and dimensions
     * @param fieldName the field name. If <CODE>null</CODE> only the widget keys
     * will be included in the field allowing it to be used as a kid field.
     */
    public BaseField(PdfWriter writer, Rectangle box, String fieldName) {
        this.writer = writer;
        setBox(box);
        this.fieldName = fieldName;
    }

    protected BaseFont getRealFont() throws IOException, DocumentException {
        if (font == null)
            return BaseFont.createFont(BaseFont.HELVETICA, BaseFont.WINANSI, false);
        else
            return font;
    }

    protected PdfAppearance getBorderAppearance() {
        PdfAppearance app = PdfAppearance.createAppearance(writer, box.getWidth(), box.getHeight());
        switch (rotation) {
            case 90:
                app.setMatrix(0, 1, -1, 0, box.getHeight(), 0);
                break;
            case 180:
                app.setMatrix(-1, 0, 0, -1, box.getWidth(), box.getHeight());
                break;
            case 270:
                app.setMatrix(0, -1, 1, 0, 0, box.getWidth());
                break;
        }
        app.saveState();
        // background
        if (backgroundColor != null) {
            app.setColorFill(backgroundColor);
            app.rectangle(0, 0, box.getWidth(), box.getHeight());
            app.fill();
        }
        // border
        if (borderStyle == PdfBorderDictionary.STYLE_UNDERLINE) {
            if (borderWidth != 0 && borderColor != null) {
                app.setColorStroke(borderColor);
                app.setLineWidth(borderWidth);
                app.moveTo(0, borderWidth / 2);
                app.lineTo(box.getWidth(), borderWidth / 2);
                app.stroke();
            }
        }
        else if (borderStyle == PdfBorderDictionary.STYLE_BEVELED) {
            if (borderWidth != 0 && borderColor != null) {
                app.setColorStroke(borderColor);
                app.setLineWidth(borderWidth);
                app.rectangle(borderWidth / 2, borderWidth / 2, box.getWidth() - borderWidth, box.getHeight() - borderWidth);
                app.stroke();
            }
            // beveled
            BaseColor actual = backgroundColor;
            if (actual == null)
                actual = BaseColor.WHITE;
            app.setGrayFill(1);
            drawTopFrame(app);
            app.setColorFill(actual.darker());
            drawBottomFrame(app);
        }
        else if (borderStyle == PdfBorderDictionary.STYLE_INSET) {
            if (borderWidth != 0 && borderColor != null) {
                app.setColorStroke(borderColor);
                app.setLineWidth(borderWidth);
                app.rectangle(borderWidth / 2, borderWidth / 2, box.getWidth() - borderWidth, box.getHeight() - borderWidth);
                app.stroke();
            }
            // inset
            app.setGrayFill(0.5f);
            drawTopFrame(app);
            app.setGrayFill(0.75f);
            drawBottomFrame(app);
        }
        else {
            if (borderWidth != 0 && borderColor != null) {
                if (borderStyle == PdfBorderDictionary.STYLE_DASHED)
                    app.setLineDash(3, 0);
                app.setColorStroke(borderColor);
                app.setLineWidth(borderWidth);
                app.rectangle(borderWidth / 2, borderWidth / 2, box.getWidth() - borderWidth, box.getHeight() - borderWidth);
                app.stroke();
                if ((options & COMB) != 0 && maxCharacterLength > 1) {
                    float step = box.getWidth() / maxCharacterLength;
                    float yb = borderWidth / 2;
                    float yt = box.getHeight() - borderWidth / 2;
                    for (int k = 1; k < maxCharacterLength; ++k) {
                        float x = step * k;
                        app.moveTo(x, yb);
                        app.lineTo(x, yt);
                    }
                    app.stroke();
                }
            }
        }
        app.restoreState();
        return app;
    }

    protected static ArrayList<String> getHardBreaks(String text) {
        ArrayList<String> arr = new ArrayList<String>();
        char cs[] = text.toCharArray();
        int len = cs.length;
        StringBuffer buf = new StringBuffer();
        for (int k = 0; k < len; ++k) {
            char c = cs[k];
            if (c == '\r') {
                if (k + 1 < len && cs[k + 1] == '\n')
                    ++k;
                arr.add(buf.toString());
                buf = new StringBuffer();
            }
            else if (c == '\n') {
                arr.add(buf.toString());
                buf = new StringBuffer();
            }
            else
                buf.append(c);
        }
        arr.add(buf.toString());
        return arr;
    }

    protected static void trimRight(StringBuffer buf) {
        int len = buf.length();
        while (true) {
            if (len == 0)
                return;
            if (buf.charAt(--len) != ' ')
                return;
            buf.setLength(len);
        }
    }

    protected static ArrayList<String> breakLines(ArrayList<String> breaks, BaseFont font, float fontSize, float width) {
        ArrayList<String> lines = new ArrayList<String>();
        StringBuffer buf = new StringBuffer();
        for (int ck = 0; ck < breaks.size(); ++ck) {
            buf.setLength(0);
            float w = 0;
            char cs[] = breaks.get(ck).toCharArray();
            int len = cs.length;
            // 0 inline first, 1 inline, 2 spaces
            int state = 0;
            int lastspace = -1;
            char c = 0;
            int refk = 0;
            for (int k = 0; k < len; ++k) {
                c = cs[k];
                switch (state) {
                    case 0:
                        w += font.getWidthPoint(c, fontSize);
                        buf.append(c);
                        if (w > width) {
                            w = 0;
                            if (buf.length() > 1) {
                                --k;
                                buf.setLength(buf.length() - 1);
                            }
                            lines.add(buf.toString());
                            buf.setLength(0);
                            refk = k;
                            if (c == ' ')
                                state = 2;
                            else
                                state = 1;
                        }
                        else {
                            if (c != ' ')
                                state = 1;
                        }
                        break;
                    case 1:
                        w += font.getWidthPoint(c, fontSize);
                        buf.append(c);
                        if (c == ' ')
                            lastspace = k;
                        if (w > width) {
                            w = 0;
                            if (lastspace >= 0) {
                                k = lastspace;
                                buf.setLength(lastspace - refk);
                                trimRight(buf);
                                lines.add(buf.toString());
                                buf.setLength(0);
                                refk = k;
                                lastspace = -1;
                                state = 2;
                            }
                            else {
                                if (buf.length() > 1) {
                                    --k;
                                    buf.setLength(buf.length() - 1);
                                }
                                lines.add(buf.toString());
                                buf.setLength(0);
                                refk = k;
                                if (c == ' ')
                                    state = 2;
                            }
                        }
                        break;
                    case 2:
                        if (c != ' ') {
                            w = 0;
                            --k;
                            state = 1;
                        }
                        break;
                }
            }
            trimRight(buf);
            lines.add(buf.toString());
        }
        return lines;
    }

    private void drawTopFrame(PdfAppearance app) {
        app.moveTo(borderWidth, borderWidth);
        app.lineTo(borderWidth, box.getHeight() - borderWidth);
        app.lineTo(box.getWidth() - borderWidth, box.getHeight() - borderWidth);
        app.lineTo(box.getWidth() - 2 * borderWidth, box.getHeight() - 2 * borderWidth);
        app.lineTo(2 * borderWidth, box.getHeight() - 2 * borderWidth);
        app.lineTo(2 * borderWidth, 2 * borderWidth);
        app.lineTo(borderWidth, borderWidth);
        app.fill();
    }

    private void drawBottomFrame(PdfAppearance app) {
        app.moveTo(borderWidth, borderWidth);
        app.lineTo(box.getWidth() - borderWidth, borderWidth);
        app.lineTo(box.getWidth() - borderWidth, box.getHeight() - borderWidth);
        app.lineTo(box.getWidth() - 2 * borderWidth, box.getHeight() - 2 * borderWidth);
        app.lineTo(box.getWidth() - 2 * borderWidth, 2 * borderWidth);
        app.lineTo(2 * borderWidth, 2 * borderWidth);
        app.lineTo(borderWidth, borderWidth);
        app.fill();
    }
    /** Gets the border width in points.
     * @return the border width in points
     */
    public float getBorderWidth() {
        return this.borderWidth;
    }

    /** Sets the border width in points. To eliminate the border
     * set the border color to <CODE>null</CODE>.
     * @param borderWidth the border width in points
     */
    public void setBorderWidth(float borderWidth) {
        this.borderWidth = borderWidth;
    }

    /** Gets the border style.
     * @return the border style
     */
    public int getBorderStyle() {
        return this.borderStyle;
    }

    /** Sets the border style. The styles are found in <CODE>PdfBorderDictionary</CODE>
     * and can be <CODE>STYLE_SOLID</CODE>, <CODE>STYLE_DASHED</CODE>,
     * <CODE>STYLE_BEVELED</CODE>, <CODE>STYLE_INSET</CODE> and
     * <CODE>STYLE_UNDERLINE</CODE>.
     * @param borderStyle the border style
     */
    public void setBorderStyle(int borderStyle) {
        this.borderStyle = borderStyle;
    }

    /** Gets the border color.
     * @return the border color
     */
    public BaseColor getBorderColor() {
        return this.borderColor;
    }

    /** Sets the border color. Set to <CODE>null</CODE> to remove
     * the border.
     * @param borderColor the border color
     */
    public void setBorderColor(BaseColor borderColor) {
        this.borderColor = borderColor;
    }

    /** Gets the background color.
     * @return the background color
     */
    public BaseColor getBackgroundColor() {
        return this.backgroundColor;
    }

    /** Sets the background color. Set to <CODE>null</CODE> for
     * transparent background.
     * @param backgroundColor the background color
     */
    public void setBackgroundColor(BaseColor backgroundColor) {
        this.backgroundColor = backgroundColor;
    }

    /** Gets the text color.
     * @return the text color
     */
    public BaseColor getTextColor() {
        return this.textColor;
    }

    /** Sets the text color. If <CODE>null</CODE> the color used
     * will be black.
     * @param textColor the text color
     */
    public void setTextColor(BaseColor textColor) {
        this.textColor = textColor;
    }

    /** Gets the text font.
     * @return the text font
     */
    public BaseFont getFont() {
        return this.font;
    }

    /** Sets the text font. If <CODE>null</CODE> then Helvetica
     * will be used.
     * @param font the text font
     */
    public void setFont(BaseFont font) {
        this.font = font;
    }

    /** Gets the font size.
     * @return the font size
     */
    public float getFontSize() {
        return this.fontSize;
    }

    /** Sets the font size. If 0 then auto-sizing will be used but
     * only for text fields.
     * @param fontSize the font size
     */
    public void setFontSize(float fontSize) {
        this.fontSize = fontSize;
    }

    /** Gets the text horizontal alignment.
     * @return the text horizontal alignment
     */
    public int getAlignment() {
        return this.alignment;
    }

    /** Sets the text horizontal alignment. It can be <CODE>Element.ALIGN_LEFT</CODE>,
     * <CODE>Element.ALIGN_CENTER</CODE> and <CODE>Element.ALIGN_RIGHT</CODE>.
     * @param alignment the text horizontal alignment
     */
    public void setAlignment(int alignment) {
        this.alignment = alignment;
    }

    /** Gets the text.
     * @return the text
     */
    public String getText() {
        return this.text;
    }

    /** Sets the text for text fields.
     * @param text the text
     */
    public void setText(String text) {
        this.text = text;
    }

    /** Gets the field dimension and position.
     * @return the field dimension and position
     */
    public Rectangle getBox() {
        return this.box;
    }

    /** Sets the field dimension and position.
     * @param box the field dimension and position
     */
    public void setBox(Rectangle box) {
        if (box == null) {
                this.box = null;
        }
        else {
                this.box = new Rectangle(box);
                this.box.normalize();
        }
    }

    /** Gets the field rotation.
     * @return the field rotation
     */
    public int getRotation() {
        return this.rotation;
    }

    /** Sets the field rotation. This value should be the same as
     * the page rotation where the field will be shown.
     * @param rotation the field rotation
     */
    public void setRotation(int rotation) {
        if (rotation % 90 != 0)
            throw new IllegalArgumentException(MessageLocalization.getComposedMessage("rotation.must.be.a.multiple.of.90"));
        rotation %= 360;
        if (rotation < 0)
            rotation += 360;
        this.rotation = rotation;
    }

    /** Convenience method to set the field rotation the same as the
     * page rotation.
     * @param page the page
     */
    public void setRotationFromPage(Rectangle page) {
        setRotation(page.getRotation());
    }

    /** Gets the field visibility flag.
     * @return the field visibility flag
     */
    public int getVisibility() {
        return this.visibility;
    }

    /** Sets the field visibility flag. This flags can be one of
     * <CODE>VISIBLE</CODE>, <CODE>HIDDEN</CODE>, <CODE>VISIBLE_BUT_DOES_NOT_PRINT</CODE>
     * and <CODE>HIDDEN_BUT_PRINTABLE</CODE>.
     * @param visibility field visibility flag
     */
    public void setVisibility(int visibility) {
        this.visibility = visibility;
    }

    /** Gets the field name.
     * @return the field name
     */
    public String getFieldName() {
        return this.fieldName;
    }

    /** Sets the field name.
     * @param fieldName the field name. If <CODE>null</CODE> only the widget keys
     * will be included in the field allowing it to be used as a kid field.
     */
    public void setFieldName(String fieldName) {
        this.fieldName = fieldName;
    }

    /** Gets the option flags.
     * @return the option flags
     */
    public int getOptions() {
        return this.options;
    }

    /** Sets the option flags. The option flags can be a combination by oring of
     * <CODE>READ_ONLY</CODE>, <CODE>REQUIRED</CODE>,
     * <CODE>MULTILINE</CODE>, <CODE>DO_NOT_SCROLL</CODE>,
     * <CODE>PASSWORD</CODE>, <CODE>FILE_SELECTION</CODE>,
     * <CODE>DO_NOT_SPELL_CHECK</CODE> and <CODE>EDIT</CODE>.
     * @param options the option flags
     */
    public void setOptions(int options) {
        this.options = options;
    }

    /** Gets the maximum length of the field's text, in characters.
     * @return the maximum length of the field's text, in characters.
     */
    public int getMaxCharacterLength() {
        return this.maxCharacterLength;
    }

    /** Sets the maximum length of the field's text, in characters.
     * It is only meaningful for text fields.
     * @param maxCharacterLength the maximum length of the field's text, in characters
     */
    public void setMaxCharacterLength(int maxCharacterLength) {
        this.maxCharacterLength = maxCharacterLength;
    }

    /**
     * Getter for property writer.
     * @return Value of property writer.
     */
    public PdfWriter getWriter() {
        return writer;
    }

    /**
     * Setter for property writer.
     * @param writer New value of property writer.
     */
    public void setWriter(PdfWriter writer) {
        this.writer = writer;
    }

    /**
     * Moves the field keys from <CODE>from</CODE> to <CODE>to</CODE>. The moved keys
     * are removed from <CODE>from</CODE>.
     * @param from the source
     * @param to the destination. It may be <CODE>null</CODE>
     */
    public static void moveFields(PdfDictionary from, PdfDictionary to) {
        for (Iterator<PdfName> i = from.getKeys().iterator(); i.hasNext();) {
            PdfName key = i.next();
            if (fieldKeys.containsKey(key)) {
                if (to != null)
                    to.put(key, from.get(key));
                i.remove();
            }
        }
    }
}