/**
 * @file llexpandabletextbox.h
 * @brief LLExpandableTextBox and related class definitions
 *
 * $LicenseInfo:firstyear=2004&license=viewerlgpl$
 * Second Life Viewer Source Code
 * Copyright (C) 2010, Linden Research, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation;
 * version 2.1 of the License only.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
 * $/LicenseInfo$
 */

#ifndef LL_LLEXPANDABLETEXTBOX_H
#define LL_LLEXPANDABLETEXTBOX_H

#include "lltexteditor.h"
#include "llscrollcontainer.h"

/**
 * LLExpandableTextBox is a text box control that will show "More" link at end of text
 * if text doesn't fit into text box. After pressing "More" the text box will expand to show
 * all text. If text is still too big, a scroll bar will appear inside expanded text box.
 */
class LLExpandableTextBox : public LLUICtrl
{
protected:

    /**
     * Extended text box. "More" link will appear at end of text if
     * text is too long to fit into text box size.
     */
    class LLTextBoxEx : public LLTextEditor
    {
    public:
        struct Params : public LLInitParam::Block<Params, LLTextEditor::Params>
        {
            Params();
        };

        // adds or removes "More" link as needed
        /*virtual*/ void reshape(S32 width, S32 height, bool called_from_parent = true);
        /*virtual*/ void setText(const LLStringExplicit& text, const LLStyle::Params& input_params = LLStyle::Params());
        void setTextBase(const std::string& text) { LLTextBase::setText(text); }

        /**
         * Returns difference between text box height and text height.
         * Value is positive if text height is greater than text box height.
         */
        virtual S32 getVerticalTextDelta();

        /**
         * Returns the height of text rect.
         */
        S32 getTextPixelHeight();

        /**
         * Shows "More" link
         */
        void showExpandText();

        /**
         * Hides "More" link
         */
        void hideExpandText();

        /**
         * Shows the "More" link if the text is too high to be completely
         * visible without expanding the text box. Hides that link otherwise.
         */
        void hideOrShowExpandTextAsNeeded();

    protected:

        LLTextBoxEx(const Params& p);
        friend class LLUICtrlFactory;

    private:
        std::string mExpanderLabel;

        bool mExpanderVisible;
    };

public:

    struct Params : public LLInitParam::Block<Params, LLUICtrl::Params>
    {
        Optional<LLTextBoxEx::Params> textbox;

        Optional<LLScrollContainer::Params> scroll;

        Optional<S32> max_height;

        Optional<bool> bg_visible,
                       expanded_bg_visible;

        Optional<LLUIColor> bg_color,
                           expanded_bg_color;

        Params();
    };

    /**
     * Sets text
     */
    virtual void setText(const std::string& str);

    /**
     * Returns text
     */
    virtual const std::string& getText() const { return mText; }

    /**
     * Sets text
     */
    /*virtual*/ void setValue(const LLSD& value);

    /**
     * Returns text
     */
    /*virtual*/ LLSD getValue() const { return mText; }

    /**
     * Collapses text box on focus_lost event
     */
    /*virtual*/ void onFocusLost();

    /**
     * Collapses text box on top_lost event
     */
    /*virtual*/ void onTopLost();

    /**
     * *HACK: Update the inner textbox shape.
     */
    void updateTextShape();
    virtual void reshape(S32 width, S32 height, bool called_from_parent = true);

    /**
     * Draws text box, collapses text box if its expanded and its parent's position changed
     */
    /*virtual*/ void draw();

    virtual ~LLExpandableTextBox();

protected:

    LLExpandableTextBox(const Params& p);
    friend class LLUICtrlFactory;

    /**
     * Expands text box.
     * A scroll bar will appear if expanded height is greater than max_height
     */
    virtual void expandTextBox();

    /**
     * Collapses text box.
     */
    virtual void collapseTextBox();

    /**
     * Collapses text box if it is expanded and its parent's position changed
     */
    virtual void collapseIfPosChanged();

    /**
     * Updates text box rect to avoid horizontal scroll bar
     */
    virtual void updateTextBoxRect();

    /**
     * User clicked on "More" link - expand text box
     */
    virtual void onExpandClicked();

    /**
     * Saves collapsed text box's states(rect, parent rect...)
     */
    virtual void saveCollapsedState();

    /**
     * Recalculate text delta considering min_height and window rect.
     */
    virtual S32 recalculateTextDelta(S32 text_delta);

    void setContentTrusted(bool trusted_content);

protected:

    std::string mText;
    LLTextBoxEx* mTextBox;
    LLScrollContainer* mScroll;

    S32 mMaxHeight;
    LLRect mCollapsedRect;
    bool mExpanded;
    LLRect mParentRect;

    bool mBGVisible;
    bool mExpandedBGVisible;
    LLUIColor mBGColor;
    LLUIColor mExpandedBGColor;
};

#endif //LL_LLEXPANDABLETEXTBOX_H