/**
 * @file llscripteditor.cpp
 * @author Cinder Roxley
 * @brief Text editor widget used for viewing and editing scripts
 *
 * $LicenseInfo:firstyear=2001&license=viewerlgpl$
 * Second Life Viewer Source Code
 * Copyright (C) 2012, 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
 * $/LicenseInfo$
 */

#include "llviewerprecompiledheaders.h"
#include "llscripteditor.h"

#include "llsyntaxid.h"
#include "lllocalcliprect.h"
#include "llviewercontrol.h"

const S32   UI_TEXTEDITOR_LINE_NUMBER_MARGIN = 32;

static LLDefaultChildRegistry::Register<LLScriptEditor> r("script_editor");

LLScriptEditor::Params::Params()
:   show_line_numbers("show_line_numbers", true),
    default_font_size("default_font_size", false)
{}


LLScriptEditor::LLScriptEditor(const Params& p)
:   LLTextEditor(p)
,   mShowLineNumbers(p.show_line_numbers),
    mUseDefaultFontSize(p.default_font_size)
{
    if (mShowLineNumbers)
    {
        mHPad += UI_TEXTEDITOR_LINE_NUMBER_MARGIN;
        updateRects();
    }
}

bool LLScriptEditor::postBuild()
{
    gSavedSettings.getControl("LSLFontSizeName")->getCommitSignal()->connect(boost::bind(&LLScriptEditor::onFontSizeChange, this));
    return LLTextEditor::postBuild();
}

void LLScriptEditor::draw()
{
    {
        // pad clipping rectangle so that cursor can draw at full width
        // when at left edge of mVisibleTextRect
        LLRect clip_rect(mVisibleTextRect);
        clip_rect.stretch(1);
        LLLocalClipRect clip(clip_rect);
    }

    LLTextBase::draw();
    drawLineNumbers();

    drawPreeditMarker();

    //RN: the decision was made to always show the orange border for keyboard focus but do not put an insertion caret
    // when in readonly mode
    mBorder->setKeyboardFocusHighlight( hasFocus() );// && !mReadOnly);
}

void LLScriptEditor::drawLineNumbers()
{
    LLGLSUIDefault gls_ui;
    LLRect scrolled_view_rect = getVisibleDocumentRect();
    LLRect content_rect = getVisibleTextRect();
    LLLocalClipRect clip(content_rect);
    S32 first_line = getFirstVisibleLine();
    S32 num_lines = getLineCount();
    if (first_line >= num_lines)
    {
        return;
    }

    S32 cursor_line = mLineInfoList[getLineNumFromDocIndex(mCursorPos)].mLineNum;

    if (mShowLineNumbers)
    {
        S32 left = 0;
        S32 top = getRect().getHeight();
        S32 bottom = 0;

        gl_rect_2d(left, top, UI_TEXTEDITOR_LINE_NUMBER_MARGIN, bottom, mReadOnlyBgColor.get() ); // line number area always read-only
        gl_rect_2d(UI_TEXTEDITOR_LINE_NUMBER_MARGIN, top, UI_TEXTEDITOR_LINE_NUMBER_MARGIN-1, bottom, LLColor4::grey3); // separator

        S32 last_line_num = -1;

        for (S32 cur_line = first_line; cur_line < num_lines; cur_line++)
        {
            line_info& line = mLineInfoList[cur_line];

            if ((line.mRect.mTop - scrolled_view_rect.mBottom) < mVisibleTextRect.mBottom)
            {
                break;
            }

            S32 line_bottom = line.mRect.mBottom - scrolled_view_rect.mBottom + mVisibleTextRect.mBottom;
            // draw the line numbers
            if(line.mLineNum != last_line_num && line.mRect.mTop <= scrolled_view_rect.mTop)
            {
                const LLWString ltext = utf8str_to_wstring(llformat("%d", line.mLineNum ));
                bool is_cur_line = cursor_line == line.mLineNum;
                const U8 style = is_cur_line ? LLFontGL::BOLD : LLFontGL::NORMAL;
                const LLColor4& fg_color = is_cur_line ? mCursorColor : mReadOnlyFgColor;
                getScriptFont()->render(
                                 ltext, // string to draw
                                 0, // begin offset
                                 UI_TEXTEDITOR_LINE_NUMBER_MARGIN - 2, // x
                                 (F32)line_bottom, // y
                                 fg_color,
                                 LLFontGL::RIGHT, // horizontal alignment
                                 LLFontGL::BOTTOM, // vertical alignment
                                 style,
                                 LLFontGL::NO_SHADOW,
                                 S32_MAX, // max chars
                                 UI_TEXTEDITOR_LINE_NUMBER_MARGIN - 2); // max pixels
                last_line_num = line.mLineNum;
            }
        }
    }
}

void LLScriptEditor::initKeywords()
{
    mKeywords.initialize(LLSyntaxIdLSL::getInstance()->getKeywordsXML());
}

void LLScriptEditor::loadKeywords()
{
    LL_PROFILE_ZONE_SCOPED;
    mKeywords.processTokens();

    LLStyleConstSP style = new LLStyle(LLStyle::Params().font(getScriptFont()).color(mDefaultColor.get()));

    segment_vec_t segment_list;
    mKeywords.findSegments(&segment_list, getWText(), *this, style);

    mSegments.clear();
    segment_set_t::iterator insert_it = mSegments.begin();
    for (segment_vec_t::iterator list_it = segment_list.begin(); list_it != segment_list.end(); ++list_it)
    {
        insert_it = mSegments.insert(insert_it, *list_it);
    }
}

void LLScriptEditor::updateSegments()
{
    if (mReflowIndex < S32_MAX && mKeywords.isLoaded() && mParseOnTheFly)
    {
        LL_PROFILE_ZONE_SCOPED;

        LLStyleConstSP style = new LLStyle(LLStyle::Params().font(getScriptFont()).color(mDefaultColor.get()));

        // HACK:  No non-ascii keywords for now
        segment_vec_t segment_list;
        mKeywords.findSegments(&segment_list, getWText(), *this, style);

        clearSegments();
        for (segment_vec_t::iterator list_it = segment_list.begin(); list_it != segment_list.end(); ++list_it)
        {
            insertSegment(*list_it);
        }
    }

    LLTextBase::updateSegments();
}

void LLScriptEditor::clearSegments()
{
    if (!mSegments.empty())
    {
        mSegments.clear();
    }
}

// Most of this is shamelessly copied from LLTextBase
void LLScriptEditor::drawSelectionBackground()
{
    // Draw selection even if we don't have keyboard focus for search/replace
    if( hasSelection() && !mLineInfoList.empty())
    {
        std::vector<LLRect> selection_rects = getSelectionRects();

        gGL.getTexUnit(0)->unbind(LLTexUnit::TT_TEXTURE);
        const LLColor4& color = mReadOnly ? mReadOnlyFgColor : mFgColor;
        F32 alpha = hasFocus() ? 0.7f : 0.3f;
        alpha *= getDrawContext().mAlpha;
        // We want to shift the color to something readable but distinct
        LLColor4 selection_color((1.f + color.mV[VRED]) * 0.5f,
                                 (1.f + color.mV[VGREEN]) * 0.5f,
                                 (1.f + color.mV[VBLUE]) * 0.5f,
                                 alpha);
        LLRect content_display_rect = getVisibleDocumentRect();

        for (std::vector<LLRect>::iterator rect_it = selection_rects.begin();
             rect_it != selection_rects.end();
             ++rect_it)
        {
            LLRect selection_rect = *rect_it;
            selection_rect = *rect_it;
            selection_rect.translate(mVisibleTextRect.mLeft - content_display_rect.mLeft, mVisibleTextRect.mBottom - content_display_rect.mBottom);
            gl_rect_2d(selection_rect, selection_color);
        }
    }
}

std::string LLScriptEditor::getScriptFontSize()
{
    static LLCachedControl<std::string> size_name(gSavedSettings, "LSLFontSizeName", "Monospace");
    return size_name;
}

LLFontGL* LLScriptEditor::getScriptFont()
{
    std::string font_size_name = mUseDefaultFontSize ? "Monospace" : getScriptFontSize();
    return LLFontGL::getFont(LLFontDescriptor("Monospace", font_size_name, 0));
}

void LLScriptEditor::onFontSizeChange()
{
    if (!mUseDefaultFontSize)
    {
        needsReflow();
    }
}