/*
 * Copyright (C) 2011 Google Inc. All rights reserved.
 * Copyright (C) 2015 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
 *     * Neither the name of Google Inc. nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "config.h"
#include "InspectorDOMDebuggerAgent.h"

#include "HTMLElement.h"
#include "InspectorDOMAgent.h"
#include "InstrumentingAgents.h"
#include <inspector/InspectorFrontendDispatchers.h>
#include <inspector/InspectorValues.h>

namespace {

enum DOMBreakpointType {
    SubtreeModified = 0,
    AttributeModified,
    NodeRemoved,
    DOMBreakpointTypesCount
};

static const char* const listenerEventCategoryType = "listener:";
static const char* const instrumentationEventCategoryType = "instrumentation:";

const uint32_t inheritableDOMBreakpointTypesMask = (1 << SubtreeModified);
const int domBreakpointDerivedTypeShift = 16;

}

using namespace Inspector;

namespace WebCore {

InspectorDOMDebuggerAgent::InspectorDOMDebuggerAgent(WebAgentContext& context, InspectorDOMAgent* domAgent, InspectorDebuggerAgent* debuggerAgent)
    : InspectorAgentBase(ASCIILiteral("DOMDebugger"), context)
    , m_backendDispatcher(Inspector::DOMDebuggerBackendDispatcher::create(context.backendDispatcher, this))
    , m_domAgent(domAgent)
    , m_debuggerAgent(debuggerAgent)
{
    m_debuggerAgent->setListener(this);
}

InspectorDOMDebuggerAgent::~InspectorDOMDebuggerAgent()
{
    ASSERT(!m_debuggerAgent);
    ASSERT(!m_instrumentingAgents.inspectorDOMDebuggerAgent());
}

// Browser debugger agent enabled only when JS debugger is enabled.
void InspectorDOMDebuggerAgent::debuggerWasEnabled()
{
    m_instrumentingAgents.setInspectorDOMDebuggerAgent(this);
}

void InspectorDOMDebuggerAgent::debuggerWasDisabled()
{
    disable();
}

void InspectorDOMDebuggerAgent::stepInto()
{
    m_pauseInNextEventListener = true;
}

void InspectorDOMDebuggerAgent::didPause()
{
    m_pauseInNextEventListener = false;
}

void InspectorDOMDebuggerAgent::disable()
{
    m_instrumentingAgents.setInspectorDOMDebuggerAgent(nullptr);
    clear();
}

void InspectorDOMDebuggerAgent::didCreateFrontendAndBackend(Inspector::FrontendRouter*, Inspector::BackendDispatcher*)
{
}

void InspectorDOMDebuggerAgent::willDestroyFrontendAndBackend(Inspector::DisconnectReason)
{
    disable();
}

void InspectorDOMDebuggerAgent::discardAgent()
{
    m_debuggerAgent->setListener(nullptr);
    m_debuggerAgent = nullptr;
}

void InspectorDOMDebuggerAgent::discardBindings()
{
    m_domBreakpoints.clear();
}

void InspectorDOMDebuggerAgent::setEventListenerBreakpoint(ErrorString& error, const String& eventName)
{
    setBreakpoint(error, String(listenerEventCategoryType) + eventName);
}

void InspectorDOMDebuggerAgent::setInstrumentationBreakpoint(ErrorString& error, const String& eventName)
{
    setBreakpoint(error, String(instrumentationEventCategoryType) + eventName);
}

void InspectorDOMDebuggerAgent::setBreakpoint(ErrorString& error, const String& eventName)
{
    if (eventName.isEmpty()) {
        error = ASCIILiteral("Event name is empty");
        return;
    }

    m_eventListenerBreakpoints.add(eventName);
}

void InspectorDOMDebuggerAgent::removeEventListenerBreakpoint(ErrorString& error, const String& eventName)
{
    removeBreakpoint(error, String(listenerEventCategoryType) + eventName);
}

void InspectorDOMDebuggerAgent::removeInstrumentationBreakpoint(ErrorString& error, const String& eventName)
{
    removeBreakpoint(error, String(instrumentationEventCategoryType) + eventName);
}

void InspectorDOMDebuggerAgent::removeBreakpoint(ErrorString& error, const String& eventName)
{
    if (eventName.isEmpty()) {
        error = ASCIILiteral("Event name is empty");
        return;
    }

    m_eventListenerBreakpoints.remove(eventName);
}

void InspectorDOMDebuggerAgent::didInvalidateStyleAttr(Node& node)
{
    if (hasBreakpoint(&node, AttributeModified)) {
        Ref<InspectorObject> eventData = InspectorObject::create();
        descriptionForDOMEvent(node, AttributeModified, false, eventData.get());
        m_debuggerAgent->breakProgram(Inspector::DebuggerFrontendDispatcher::Reason::DOM, WTFMove(eventData));
    }
}

void InspectorDOMDebuggerAgent::didInsertDOMNode(Node& node)
{
    if (m_domBreakpoints.size()) {
        uint32_t mask = m_domBreakpoints.get(InspectorDOMAgent::innerParentNode(&node));
        uint32_t inheritableTypesMask = (mask | (mask >> domBreakpointDerivedTypeShift)) & inheritableDOMBreakpointTypesMask;
        if (inheritableTypesMask)
            updateSubtreeBreakpoints(&node, inheritableTypesMask, true);
    }
}

void InspectorDOMDebuggerAgent::didRemoveDOMNode(Node& node)
{
    if (m_domBreakpoints.size()) {
        // Remove subtree breakpoints.
        m_domBreakpoints.remove(&node);
        Vector<Node*> stack(1, InspectorDOMAgent::innerFirstChild(&node));
        do {
            Node* node = stack.last();
            stack.removeLast();
            if (!node)
                continue;
            m_domBreakpoints.remove(node);
            stack.append(InspectorDOMAgent::innerFirstChild(node));
            stack.append(InspectorDOMAgent::innerNextSibling(node));
        } while (!stack.isEmpty());
    }
}

static int domTypeForName(ErrorString& errorString, const String& typeString)
{
    if (typeString == "subtree-modified")
        return SubtreeModified;
    if (typeString == "attribute-modified")
        return AttributeModified;
    if (typeString == "node-removed")
        return NodeRemoved;
    errorString = makeString("Unknown DOM breakpoint type: ", typeString);
    return -1;
}

static String domTypeName(int type)
{
    switch (type) {
    case SubtreeModified: return ASCIILiteral("subtree-modified");
    case AttributeModified: return ASCIILiteral("attribute-modified");
    case NodeRemoved: return ASCIILiteral("node-removed");
    default: break;
    }
    return emptyString();
}

void InspectorDOMDebuggerAgent::setDOMBreakpoint(ErrorString& errorString, int nodeId, const String& typeString)
{
    Node* node = m_domAgent->assertNode(errorString, nodeId);
    if (!node)
        return;

    int type = domTypeForName(errorString, typeString);
    if (type == -1)
        return;

    uint32_t rootBit = 1 << type;
    m_domBreakpoints.set(node, m_domBreakpoints.get(node) | rootBit);
    if (rootBit & inheritableDOMBreakpointTypesMask) {
        for (Node* child = InspectorDOMAgent::innerFirstChild(node); child; child = InspectorDOMAgent::innerNextSibling(child))
            updateSubtreeBreakpoints(child, rootBit, true);
    }
}

void InspectorDOMDebuggerAgent::removeDOMBreakpoint(ErrorString& errorString, int nodeId, const String& typeString)
{
    Node* node = m_domAgent->assertNode(errorString, nodeId);
    if (!node)
        return;
    int type = domTypeForName(errorString, typeString);
    if (type == -1)
        return;

    uint32_t rootBit = 1 << type;
    uint32_t mask = m_domBreakpoints.get(node) & ~rootBit;
    if (mask)
        m_domBreakpoints.set(node, mask);
    else
        m_domBreakpoints.remove(node);

    if ((rootBit & inheritableDOMBreakpointTypesMask) && !(mask & (rootBit << domBreakpointDerivedTypeShift))) {
        for (Node* child = InspectorDOMAgent::innerFirstChild(node); child; child = InspectorDOMAgent::innerNextSibling(child))
            updateSubtreeBreakpoints(child, rootBit, false);
    }
}

void InspectorDOMDebuggerAgent::willInsertDOMNode(Node& parent)
{
    if (hasBreakpoint(&parent, SubtreeModified)) {
        Ref<InspectorObject> eventData = InspectorObject::create();
        descriptionForDOMEvent(parent, SubtreeModified, true, eventData.get());
        m_debuggerAgent->breakProgram(Inspector::DebuggerFrontendDispatcher::Reason::DOM, WTFMove(eventData));
    }
}

void InspectorDOMDebuggerAgent::willRemoveDOMNode(Node& node)
{
    Node* parentNode = InspectorDOMAgent::innerParentNode(&node);
    if (hasBreakpoint(&node, NodeRemoved)) {
        Ref<InspectorObject> eventData = InspectorObject::create();
        descriptionForDOMEvent(node, NodeRemoved, false, eventData.get());
        m_debuggerAgent->breakProgram(Inspector::DebuggerFrontendDispatcher::Reason::DOM, WTFMove(eventData));
    } else if (parentNode && hasBreakpoint(parentNode, SubtreeModified)) {
        Ref<InspectorObject> eventData = InspectorObject::create();
        descriptionForDOMEvent(node, SubtreeModified, false, eventData.get());
        m_debuggerAgent->breakProgram(Inspector::DebuggerFrontendDispatcher::Reason::DOM, WTFMove(eventData));
    }
}

void InspectorDOMDebuggerAgent::willModifyDOMAttr(Element& element)
{
    if (hasBreakpoint(&element, AttributeModified)) {
        Ref<InspectorObject> eventData = InspectorObject::create();
        descriptionForDOMEvent(element, AttributeModified, false, eventData.get());
        m_debuggerAgent->breakProgram(Inspector::DebuggerFrontendDispatcher::Reason::DOM, WTFMove(eventData));
    }
}

void InspectorDOMDebuggerAgent::descriptionForDOMEvent(Node& target, int breakpointType, bool insertion, InspectorObject& description)
{
    ASSERT(hasBreakpoint(&target, breakpointType));

    Node* breakpointOwner = &target;
    if ((1 << breakpointType) & inheritableDOMBreakpointTypesMask) {
        // For inheritable breakpoint types, target node isn't always the same as the node that owns a breakpoint.
        // Target node may be unknown to frontend, so we need to push it first.
        RefPtr<Inspector::Protocol::Runtime::RemoteObject> targetNodeObject = m_domAgent->resolveNode(&target, InspectorDebuggerAgent::backtraceObjectGroup);
        description.setValue("targetNode", targetNodeObject);

        // Find breakpoint owner node.
        if (!insertion)
            breakpointOwner = InspectorDOMAgent::innerParentNode(&target);
        ASSERT(breakpointOwner);
        while (!(m_domBreakpoints.get(breakpointOwner) & (1 << breakpointType))) {
            Node* parentNode = InspectorDOMAgent::innerParentNode(breakpointOwner);
            if (!parentNode)
                break;
            breakpointOwner = parentNode;
        }

        if (breakpointType == SubtreeModified)
            description.setBoolean("insertion", insertion);
    }

    int breakpointOwnerNodeId = m_domAgent->boundNodeId(breakpointOwner);
    ASSERT(breakpointOwnerNodeId);
    description.setInteger("nodeId", breakpointOwnerNodeId);
    description.setString("type", domTypeName(breakpointType));
}

bool InspectorDOMDebuggerAgent::hasBreakpoint(Node* node, int type)
{
    uint32_t rootBit = 1 << type;
    uint32_t derivedBit = rootBit << domBreakpointDerivedTypeShift;
    return m_domBreakpoints.get(node) & (rootBit | derivedBit);
}

void InspectorDOMDebuggerAgent::updateSubtreeBreakpoints(Node* node, uint32_t rootMask, bool set)
{
    uint32_t oldMask = m_domBreakpoints.get(node);
    uint32_t derivedMask = rootMask << domBreakpointDerivedTypeShift;
    uint32_t newMask = set ? oldMask | derivedMask : oldMask & ~derivedMask;
    if (newMask)
        m_domBreakpoints.set(node, newMask);
    else
        m_domBreakpoints.remove(node);

    uint32_t newRootMask = rootMask & ~newMask;
    if (!newRootMask)
        return;

    for (Node* child = InspectorDOMAgent::innerFirstChild(node); child; child = InspectorDOMAgent::innerNextSibling(child))
        updateSubtreeBreakpoints(child, newRootMask, set);
}

void InspectorDOMDebuggerAgent::pauseOnNativeEventIfNeeded(bool isDOMEvent, const String& eventName, bool synchronous)
{
    String fullEventName = (isDOMEvent ? listenerEventCategoryType : instrumentationEventCategoryType) + eventName;
    if (m_pauseInNextEventListener)
        m_pauseInNextEventListener = false;
    else {
        if (!m_eventListenerBreakpoints.contains(fullEventName))
            return;
    }

    Ref<InspectorObject> eventData = InspectorObject::create();
    eventData->setString("eventName", fullEventName);
    if (synchronous)
        m_debuggerAgent->breakProgram(Inspector::DebuggerFrontendDispatcher::Reason::EventListener, WTFMove(eventData));
    else
        m_debuggerAgent->schedulePauseOnNextStatement(Inspector::DebuggerFrontendDispatcher::Reason::EventListener, WTFMove(eventData));
}

void InspectorDOMDebuggerAgent::setXHRBreakpoint(ErrorString&, const String& url)
{
    if (url.isEmpty()) {
        m_pauseOnAllXHRsEnabled = true;
        return;
    }

    m_xhrBreakpoints.add(url);
}

void InspectorDOMDebuggerAgent::removeXHRBreakpoint(ErrorString&, const String& url)
{
    if (url.isEmpty()) {
        m_pauseOnAllXHRsEnabled = false;
        return;
    }

    m_xhrBreakpoints.remove(url);
}

void InspectorDOMDebuggerAgent::willSendXMLHttpRequest(const String& url)
{
    String breakpointURL;
    if (m_pauseOnAllXHRsEnabled)
        breakpointURL = emptyString();
    else {
        for (auto& breakpoint : m_xhrBreakpoints) {
            if (url.contains(breakpoint)) {
                breakpointURL = breakpoint;
                break;
            }
        }
    }

    if (breakpointURL.isNull())
        return;

    Ref<InspectorObject> eventData = InspectorObject::create();
    eventData->setString("breakpointURL", breakpointURL);
    eventData->setString("url", url);
    m_debuggerAgent->breakProgram(Inspector::DebuggerFrontendDispatcher::Reason::XHR, WTFMove(eventData));
}

void InspectorDOMDebuggerAgent::clear()
{
    m_domBreakpoints.clear();
    m_pauseInNextEventListener = false;
}

} // namespace WebCore