/*

 * Copyright 2016 Google Inc.

 *

 * Use of this source code is governed by a BSD-style license that can be

 * found in the LICENSE file.

 */

#include "modules/svg/include/SkSVGSVG.h"

#include "include/core/SkCanvas.h"

#include "include/core/SkMatrix.h"

#include "include/core/SkRect.h"

#include "modules/svg/include/SkSVGAttribute.h"

#include "modules/svg/include/SkSVGRenderContext.h"

#include "modules/svg/include/SkSVGValue.h"

void SkSVGSVG::renderNode(const SkSVGRenderContext& ctx, const SkSVGIRI& iri) const {

    SkSVGRenderContext localContext(ctx, this);

    SkSVGRenderContext::BorrowedNode node = localContext.findNodeById(iri);

    if (!node) {

        return;

    }

    if (this->onPrepareToRender(&localContext)) {

        if (this == node.get()) {

            this->onRender(ctx);

        } else {

            node->render(localContext);

        }

    }

}

bool SkSVGSVG::onPrepareToRender(SkSVGRenderContext* ctx) const {

    // x/y are ignored for outermost svg elements

    const auto x = fType == Type::kInner ? fX : SkSVGLength(0);

    const auto y = fType == Type::kInner ? fY : SkSVGLength(0);

    auto viewPortRect  = ctx->lengthContext().resolveRect(x, y, fWidth, fHeight);

    auto contentMatrix = SkMatrix::Translate(viewPortRect.x(), viewPortRect.y());

    auto viewPort      = SkSize::Make(viewPortRect.width(), viewPortRect.height());

    if (fViewBox.isValid()) {

        const SkRect& viewBox = *fViewBox;

        // An empty viewbox disables rendering.

        if (viewBox.isEmpty()) {

            return false;

        }

        // A viewBox overrides the intrinsic viewport.

        viewPort = SkSize::Make(viewBox.width(), viewBox.height());

        contentMatrix.preConcat(ComputeViewboxMatrix(viewBox, viewPortRect, fPreserveAspectRatio));

    }

    if (!contentMatrix.isIdentity()) {

        ctx->saveOnce();

        ctx->canvas()->concat(contentMatrix);

    }

    if (viewPort != ctx->lengthContext().viewPort()) {

        ctx->writableLengthContext()->setViewPort(viewPort);

    }

    return this->INHERITED::onPrepareToRender(ctx);

}

void SkSVGSVG::onSetAttribute(SkSVGAttribute attr, const SkSVGValue& v) {

    switch (attr) {

    case SkSVGAttribute::kX:

        if (const auto* x = v.as<SkSVGLengthValue>()) {

            this->setX(*x);

        }

        break;

    case SkSVGAttribute::kY:

        if (const auto* y = v.as<SkSVGLengthValue>()) {

            this->setY(*y);

        }

        break;

    case SkSVGAttribute::kWidth:

        if (const auto* w = v.as<SkSVGLengthValue>()) {

            this->setWidth(*w);

        }

        break;

    case SkSVGAttribute::kHeight:

        if (const auto* h = v.as<SkSVGLengthValue>()) {

            this->setHeight(*h);

        }

        break;

    case SkSVGAttribute::kViewBox:

        if (const auto* vb = v.as<SkSVGViewBoxValue>()) {

            this->setViewBox(*vb);

        }

        break;

    case SkSVGAttribute::kPreserveAspectRatio:

        if (const auto* par = v.as<SkSVGPreserveAspectRatioValue>()) {

            this->setPreserveAspectRatio(*par);

        }

        break;

    default:

        this->INHERITED::onSetAttribute(attr, v);

    }

}

// https://www.w3.org/TR/SVG11/coords.html#IntrinsicSizing

SkSize SkSVGSVG::intrinsicSize(const SkSVGLengthContext& lctx) const {

    // Percentage values do not provide an intrinsic size.

    if (fWidth.unit() == SkSVGLength::Unit::kPercentage ||

        fHeight.unit() == SkSVGLength::Unit::kPercentage) {

        return SkSize::Make(0, 0);

    }

    return SkSize::Make(lctx.resolve(fWidth, SkSVGLengthContext::LengthType::kHorizontal),

                        lctx.resolve(fHeight, SkSVGLengthContext::LengthType::kVertical));

}