/**
 * Copyright (C) 2006, 2007, 2010 Apple Inc. All rights reserved.
 *           (C) 2008 Torch Mobile Inc. All rights reserved.
 *               (http://www.torchmobile.com/)
 * Copyright (C) 2010 Google Inc. All rights reserved.
 * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * 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
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public License
 * along with this library; see the file COPYING.LIB.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 *
 */

#include "core/layout/LayoutTextControlSingleLine.h"

#include "core/CSSValueKeywords.h"
#include "core/InputTypeNames.h"
#include "core/dom/shadow/ShadowRoot.h"
#include "core/editing/FrameSelection.h"
#include "core/frame/LocalFrame.h"
#include "core/html/shadow/ShadowElementNames.h"
#include "core/input/KeyboardEventManager.h"
#include "core/layout/HitTestResult.h"
#include "core/layout/LayoutAnalyzer.h"
#include "core/layout/LayoutTheme.h"
#include "core/paint/LayoutObjectDrawingRecorder.h"
#include "core/paint/PaintInfo.h"
#include "core/paint/PaintLayer.h"
#include "core/paint/ThemePainter.h"
#include "platform/fonts/SimpleFontData.h"

namespace blink {

using namespace HTMLNames;

LayoutTextControlSingleLine::LayoutTextControlSingleLine(
    HTMLInputElement* element)
    : LayoutTextControl(element), m_shouldDrawCapsLockIndicator(false) {}

LayoutTextControlSingleLine::~LayoutTextControlSingleLine() {}

inline Element* LayoutTextControlSingleLine::containerElement() const {
  return inputElement()->userAgentShadowRoot()->getElementById(
      ShadowElementNames::textFieldContainer());
}

inline Element* LayoutTextControlSingleLine::editingViewPortElement() const {
  return inputElement()->userAgentShadowRoot()->getElementById(
      ShadowElementNames::editingViewPort());
}

inline HTMLElement* LayoutTextControlSingleLine::innerSpinButtonElement()
    const {
  return toHTMLElement(inputElement()->userAgentShadowRoot()->getElementById(
      ShadowElementNames::spinButton()));
}

void LayoutTextControlSingleLine::paint(const PaintInfo& paintInfo,
                                        const LayoutPoint& paintOffset) const {
  LayoutTextControl::paint(paintInfo, paintOffset);

  if (shouldPaintSelfBlockBackground(paintInfo.phase) &&
      m_shouldDrawCapsLockIndicator) {
    if (LayoutObjectDrawingRecorder::useCachedDrawingIfPossible(
            paintInfo.context, *this, paintInfo.phase))
      return;

    LayoutRect contentsRect = contentBoxRect();

    // Center in the block progression direction.
    if (isHorizontalWritingMode())
      contentsRect.setY((size().height() - contentsRect.height()) / 2);
    else
      contentsRect.setX((size().width() - contentsRect.width()) / 2);

    // Convert the rect into the coords used for painting the content
    contentsRect.moveBy(paintOffset + location());
    IntRect snappedRect = pixelSnappedIntRect(contentsRect);
    LayoutObjectDrawingRecorder recorder(paintInfo.context, *this,
                                         paintInfo.phase, snappedRect);
    LayoutTheme::theme().painter().paintCapsLockIndicator(*this, paintInfo,
                                                          snappedRect);
  }
}

void LayoutTextControlSingleLine::layout() {
  LayoutAnalyzer::Scope analyzer(*this);

  LayoutBlockFlow::layoutBlock(true);

  LayoutBox* innerEditorLayoutObject = innerEditorElement()->layoutBox();
  Element* container = containerElement();
  LayoutBox* containerLayoutObject =
      container ? container->layoutBox() : nullptr;
  // Center the child block in the block progression direction (vertical
  // centering for horizontal text fields).
  if (!container && innerEditorLayoutObject &&
      innerEditorLayoutObject->size().height() != contentLogicalHeight()) {
    LayoutUnit logicalHeightDiff =
        innerEditorLayoutObject->logicalHeight() - contentLogicalHeight();
    innerEditorLayoutObject->setLogicalTop(
        innerEditorLayoutObject->logicalTop() -
        (logicalHeightDiff / 2 + layoutMod(logicalHeightDiff, 2)));
  } else if (container && containerLayoutObject &&
             containerLayoutObject->size().height() != contentLogicalHeight()) {
    LayoutUnit logicalHeightDiff =
        containerLayoutObject->logicalHeight() - contentLogicalHeight();
    containerLayoutObject->setLogicalTop(
        containerLayoutObject->logicalTop() -
        (logicalHeightDiff / 2 + layoutMod(logicalHeightDiff, 2)));
  }

  HTMLElement* placeholderElement = inputElement()->placeholderElement();
  if (LayoutBox* placeholderBox =
          placeholderElement ? placeholderElement->layoutBox() : 0) {
    LayoutSize innerEditorSize;

    if (innerEditorLayoutObject)
      innerEditorSize = innerEditorLayoutObject->size();
    placeholderBox->mutableStyleRef().setWidth(Length(
        innerEditorSize.width() - placeholderBox->borderAndPaddingWidth(),
        Fixed));
    bool neededLayout = placeholderBox->needsLayout();
    placeholderBox->layoutIfNeeded();
    LayoutPoint textOffset;
    if (innerEditorLayoutObject)
      textOffset = innerEditorLayoutObject->location();
    if (editingViewPortElement() && editingViewPortElement()->layoutBox())
      textOffset +=
          toLayoutSize(editingViewPortElement()->layoutBox()->location());
    if (containerLayoutObject)
      textOffset += toLayoutSize(containerLayoutObject->location());
    if (innerEditorLayoutObject) {
      // We use inlineBlockBaseline() for innerEditor because it has no
      // inline boxes when we show the placeholder.
      int innerEditorBaseline =
          innerEditorLayoutObject->inlineBlockBaseline(HorizontalLine);
      // We use firstLineBoxBaseline() for placeholder.
      // TODO(tkent): It's inconsistent with innerEditorBaseline. However
      // placeholderBox->inlineBlockBase() is unexpectedly larger.
      int placeholderBaseline = placeholderBox->firstLineBoxBaseline();
      textOffset += LayoutSize(0, innerEditorBaseline - placeholderBaseline);
    }
    placeholderBox->setLocation(textOffset);

    // The placeholder gets layout last, after the parent text control and its
    // other children, so in order to get the correct overflow from the
    // placeholder we need to recompute it now.
    if (neededLayout)
      computeOverflow(clientLogicalBottom());
  }
}

bool LayoutTextControlSingleLine::nodeAtPoint(
    HitTestResult& result,
    const HitTestLocation& locationInContainer,
    const LayoutPoint& accumulatedOffset,
    HitTestAction hitTestAction) {
  if (!LayoutTextControl::nodeAtPoint(result, locationInContainer,
                                      accumulatedOffset, hitTestAction))
    return false;

  // Say that we hit the inner text element if
  //  - we hit a node inside the inner text element,
  //  - we hit the <input> element (e.g. we're over the border or padding), or
  //  - we hit regions not in any decoration buttons.
  Element* container = containerElement();
  if (result.innerNode()->isDescendantOf(innerEditorElement()) ||
      result.innerNode() == node() ||
      (container && container == result.innerNode())) {
    LayoutPoint pointInParent = locationInContainer.point();
    if (container && editingViewPortElement()) {
      if (editingViewPortElement()->layoutBox())
        pointInParent -=
            toLayoutSize(editingViewPortElement()->layoutBox()->location());
      if (container->layoutBox())
        pointInParent -= toLayoutSize(container->layoutBox()->location());
    }
    hitInnerEditorElement(result, pointInParent, accumulatedOffset);
  }
  return true;
}

void LayoutTextControlSingleLine::styleDidChange(
    StyleDifference diff,
    const ComputedStyle* oldStyle) {
  LayoutTextControl::styleDidChange(diff, oldStyle);
  if (HTMLElement* placeholder = inputElement()->placeholderElement())
    placeholder->setInlineStyleProperty(
        CSSPropertyTextOverflow,
        textShouldBeTruncated() ? CSSValueEllipsis : CSSValueClip);
}

void LayoutTextControlSingleLine::capsLockStateMayHaveChanged() {
  if (!node())
    return;

  // Only draw the caps lock indicator if these things are true:
  // 1) The field is a password field
  // 2) The frame is active
  // 3) The element is focused
  // 4) The caps lock is on
  bool shouldDrawCapsLockIndicator = false;

  if (LocalFrame* frame = document().frame())
    shouldDrawCapsLockIndicator =
        inputElement()->type() == InputTypeNames::password &&
        frame->selection().isFocusedAndActive() &&
        document().focusedElement() == node() &&
        KeyboardEventManager::currentCapsLockState();

  if (shouldDrawCapsLockIndicator != m_shouldDrawCapsLockIndicator) {
    m_shouldDrawCapsLockIndicator = shouldDrawCapsLockIndicator;
    setShouldDoFullPaintInvalidation();
  }
}

bool LayoutTextControlSingleLine::hasControlClip() const {
  return true;
}

LayoutRect LayoutTextControlSingleLine::controlClipRect(
    const LayoutPoint& additionalOffset) const {
  LayoutRect clipRect = paddingBoxRect();
  clipRect.moveBy(additionalOffset);
  return clipRect;
}

float LayoutTextControlSingleLine::getAvgCharWidth(
    const AtomicString& family) const {
  // Match the default system font to the width of MS Shell Dlg, the default
  // font for textareas in Firefox, Safari Win and IE for some encodings (in
  // IE, the default font is encoding specific). 901 is the avgCharWidth value
  // in the OS/2 table for MS Shell Dlg.
  if (LayoutTheme::theme().needsHackForTextControlWithFontFamily(family))
    return scaleEmToUnits(901);

  return LayoutTextControl::getAvgCharWidth(family);
}

LayoutUnit LayoutTextControlSingleLine::preferredContentLogicalWidth(
    float charWidth) const {
  int factor;
  bool includesDecoration = inputElement()->sizeShouldIncludeDecoration(factor);
  if (factor <= 0)
    factor = 20;

  LayoutUnit result = LayoutUnit::fromFloatCeil(charWidth * factor);

  float maxCharWidth = 0.f;
  const Font& font = style()->font();
  AtomicString family = font.getFontDescription().family().family();
  // Match the default system font to the width of MS Shell Dlg, the default
  // font for textareas in Firefox, Safari Win and IE for some encodings (in
  // IE, the default font is encoding specific). 4027 is the (xMax - xMin)
  // value in the "head" font table for MS Shell Dlg.
  if (LayoutTheme::theme().needsHackForTextControlWithFontFamily(family))
    maxCharWidth = scaleEmToUnits(4027);
  else if (hasValidAvgCharWidth(font.primaryFont(), family))
    maxCharWidth = roundf(font.primaryFont()->maxCharWidth());

  // For text inputs, IE adds some extra width.
  if (maxCharWidth > 0.f)
    result += maxCharWidth - charWidth;

  if (includesDecoration) {
    HTMLElement* spinButton = innerSpinButtonElement();
    if (LayoutBox* spinLayoutObject =
            spinButton ? spinButton->layoutBox() : 0) {
      result += spinLayoutObject->borderAndPaddingLogicalWidth();
      // Since the width of spinLayoutObject is not calculated yet,
      // spinLayoutObject->logicalWidth() returns 0.
      // So ensureComputedStyle()->logicalWidth() is used instead.
      result += spinButton->ensureComputedStyle()->logicalWidth().value();
    }
  }

  return result;
}

LayoutUnit LayoutTextControlSingleLine::computeControlLogicalHeight(
    LayoutUnit lineHeight,
    LayoutUnit nonContentHeight) const {
  return lineHeight + nonContentHeight;
}

PassRefPtr<ComputedStyle> LayoutTextControlSingleLine::createInnerEditorStyle(
    const ComputedStyle& startStyle) const {
  RefPtr<ComputedStyle> textBlockStyle = ComputedStyle::create();
  textBlockStyle->inheritFrom(startStyle);
  adjustInnerEditorStyle(*textBlockStyle);

  textBlockStyle->setWhiteSpace(EWhiteSpace::kPre);
  textBlockStyle->setOverflowWrap(NormalOverflowWrap);
  textBlockStyle->setTextOverflow(textShouldBeTruncated() ? TextOverflowEllipsis
                                                          : TextOverflowClip);

  int computedLineHeight =
      lineHeight(true, HorizontalLine, PositionOfInteriorLineBoxes).toInt();
  // Do not allow line-height to be smaller than our default.
  if (textBlockStyle->fontSize() >= computedLineHeight)
    textBlockStyle->setLineHeight(ComputedStyle::initialLineHeight());

  // We'd like to remove line-height if it's unnecessary because
  // overflow:scroll clips editing text by line-height.
  Length logicalHeight = startStyle.logicalHeight();
  // Here, we remove line-height if the INPUT fixed height is taller than the
  // line-height.  It's not the precise condition because logicalHeight
  // includes border and padding if box-sizing:border-box, and there are cases
  // in which we don't want to remove line-height with percent or calculated
  // length.
  // TODO(tkent): This should be done during layout.
  if (logicalHeight.isPercentOrCalc() ||
      (logicalHeight.isFixed() &&
       logicalHeight.getFloatValue() > computedLineHeight))
    textBlockStyle->setLineHeight(ComputedStyle::initialLineHeight());

  textBlockStyle->setDisplay(EDisplay::Block);
  textBlockStyle->setUnique(true);

  if (inputElement()->shouldRevealPassword())
    textBlockStyle->setTextSecurity(TSNONE);

  textBlockStyle->setOverflowX(EOverflow::kScroll);
  // overflow-y:visible doesn't work because overflow-x:scroll makes a layer.
  textBlockStyle->setOverflowY(EOverflow::kScroll);
  RefPtr<ComputedStyle> noScrollbarStyle = ComputedStyle::create();
  noScrollbarStyle->setStyleType(PseudoIdScrollbar);
  noScrollbarStyle->setDisplay(EDisplay::None);
  textBlockStyle->addCachedPseudoStyle(noScrollbarStyle);
  textBlockStyle->setHasPseudoStyle(PseudoIdScrollbar);

  return textBlockStyle.release();
}

bool LayoutTextControlSingleLine::textShouldBeTruncated() const {
  return document().focusedElement() != node() &&
         styleRef().getTextOverflow() == TextOverflowEllipsis;
}

void LayoutTextControlSingleLine::autoscroll(const IntPoint& position) {
  LayoutBox* layoutObject = innerEditorElement()->layoutBox();
  if (!layoutObject)
    return;

  layoutObject->autoscroll(position);
}

LayoutUnit LayoutTextControlSingleLine::scrollWidth() const {
  if (LayoutBox* inner =
          innerEditorElement() ? innerEditorElement()->layoutBox() : 0) {
    // Adjust scrollWidth to inculde input element horizontal paddings and
    // decoration width
    LayoutUnit adjustment = clientWidth() - inner->clientWidth();
    return inner->scrollWidth() + adjustment;
  }
  return LayoutBlockFlow::scrollWidth();
}

LayoutUnit LayoutTextControlSingleLine::scrollHeight() const {
  if (LayoutBox* inner =
          innerEditorElement() ? innerEditorElement()->layoutBox() : 0) {
    // Adjust scrollHeight to include input element vertical paddings and
    // decoration height
    LayoutUnit adjustment = clientHeight() - inner->clientHeight();
    return inner->scrollHeight() + adjustment;
  }
  return LayoutBlockFlow::scrollHeight();
}

LayoutUnit LayoutTextControlSingleLine::scrollLeft() const {
  if (innerEditorElement())
    return LayoutUnit(innerEditorElement()->scrollLeft());
  return LayoutBlockFlow::scrollLeft();
}

LayoutUnit LayoutTextControlSingleLine::scrollTop() const {
  if (innerEditorElement())
    return LayoutUnit(innerEditorElement()->scrollTop());
  return LayoutBlockFlow::scrollTop();
}

void LayoutTextControlSingleLine::setScrollLeft(LayoutUnit newLeft) {
  if (innerEditorElement())
    innerEditorElement()->setScrollLeft(newLeft);
}

void LayoutTextControlSingleLine::setScrollTop(LayoutUnit newTop) {
  if (innerEditorElement())
    innerEditorElement()->setScrollTop(newTop);
}

void LayoutTextControlSingleLine::addOverflowFromChildren() {
  // If the INPUT content height is smaller than the font height, the
  // inner-editor element overflows the INPUT box intentionally, however it
  // shouldn't affect outside of the INPUT box.  So we ignore child overflow.
}

HTMLInputElement* LayoutTextControlSingleLine::inputElement() const {
  return toHTMLInputElement(node());
}

}  // namespace blink