/*
 * Copyright (C) 2008-2022 Apple Inc. All rights reserved.
 * Copyright (C) 2012 Research In Motion Limited. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1.  Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 * 2.  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.
 * 3.  Neither the name of Apple Inc. ("Apple") 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 APPLE AND ITS 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 APPLE OR ITS 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.
 */

#pragma once

#include "JSCJSValue.h"
#include "MacroAssemblerCodeRef.h"
#include "Opcode.h"
#include <variant>
#include <wtf/HashMap.h>

#if ENABLE(C_LOOP)
#include "CLoopStack.h"
#endif


namespace JSC {

#if ENABLE(WEBASSEMBLY)
namespace Wasm {
class Callee;
struct HandlerInfo;
}
#endif

template<typename> struct BaseInstruction;
struct JSOpcodeTraits;
struct WasmOpcodeTraits;
using JSInstruction = BaseInstruction<JSOpcodeTraits>;
using WasmInstruction = BaseInstruction<WasmOpcodeTraits>;

using JSOrWasmInstruction = std::variant<const JSInstruction*, const WasmInstruction*>;

    class ArgList;
    class CodeBlock;
    class EvalExecutable;
    class Exception;
    class FunctionExecutable;
    class VM;
    class JSFunction;
    class JSGlobalObject;
    class JSModuleEnvironment;
    class JSModuleRecord;
    class LLIntOffsetsExtractor;
    class ProgramExecutable;
    class ModuleProgramExecutable;
    class Register;
    class JSObject;
    class JSScope;
    class SourceCode;
    class StackFrame;
    enum class HandlerType : uint8_t;
    struct CallFrameClosure;
    struct HandlerInfo;
    struct ProtoCallFrame;

    enum DebugHookType {
        WillExecuteProgram,
        DidExecuteProgram,
        DidEnterCallFrame,
        DidReachDebuggerStatement,
        WillLeaveCallFrame,
        WillExecuteStatement,
        WillExecuteExpression,
    };

    enum StackFrameCodeType {
        StackFrameGlobalCode,
        StackFrameEvalCode,
        StackFrameModuleCode,
        StackFrameFunctionCode,
        StackFrameNativeCode
    };

    struct CatchInfo {
        CatchInfo() = default;

        CatchInfo(const HandlerInfo*, CodeBlock*);
#if ENABLE(WEBASSEMBLY)
        CatchInfo(const Wasm::HandlerInfo*, const Wasm::Callee*);
#endif

        bool m_valid { false };
        HandlerType m_type;
#if ENABLE(JIT)
        MacroAssemblerCodePtr<ExceptionHandlerPtrTag> m_nativeCode;
#endif

        JSOrWasmInstruction m_catchPCForInterpreter;
    };

    class Interpreter {
        WTF_MAKE_FAST_ALLOCATED;
        friend class CachedCall;
        friend class LLIntOffsetsExtractor;
        friend class JIT;
        friend class VM;

    public:
        Interpreter();
        ~Interpreter();
        
#if ENABLE(C_LOOP)
        CLoopStack& cloopStack() { return m_cloopStack; }
        const CLoopStack& cloopStack() const { return m_cloopStack; }
#endif
        
        static inline Opcode getOpcode(OpcodeID);

        static inline OpcodeID getOpcodeID(Opcode);

#if ASSERT_ENABLED
        static bool isOpcode(Opcode);
#endif

        JSValue executeProgram(const SourceCode&, JSGlobalObject*, JSObject* thisObj);
        JSValue executeModuleProgram(JSModuleRecord*, ModuleProgramExecutable*, JSGlobalObject*, JSModuleEnvironment*, JSValue sentValue, JSValue resumeMode);
        JSValue executeCall(JSGlobalObject*, JSObject* function, const CallData&, JSValue thisValue, const ArgList&);
        JSObject* executeConstruct(JSGlobalObject*, JSObject* function, const CallData&, const ArgList&, JSValue newTarget);
        JSValue execute(EvalExecutable*, JSGlobalObject*, JSValue thisValue, JSScope*);

        void getArgumentsData(CallFrame*, JSFunction*&, ptrdiff_t& firstParameterIndex, Register*& argv, int& argc);

        NEVER_INLINE CatchInfo unwind(VM&, CallFrame*&, Exception*);
        void notifyDebuggerOfExceptionToBeThrown(VM&, JSGlobalObject*, CallFrame*, Exception*);
        NEVER_INLINE void debug(CallFrame*, DebugHookType);
        static String stackTraceAsString(VM&, const Vector<StackFrame>&);

        void getStackTrace(JSCell* owner, Vector<StackFrame>& results, size_t framesToSkip = 0, size_t maxStackSize = std::numeric_limits<size_t>::max());

    private:
        enum ExecutionFlag { Normal, InitializeAndReturn };
        
        static JSValue checkedReturn(JSValue returnValue)
        {
            ASSERT(returnValue);
            return returnValue;
        }
        
        static JSObject* checkedReturn(JSObject* returnValue)
        {
            ASSERT(returnValue);
            return returnValue;
        }

        CallFrameClosure prepareForRepeatCall(FunctionExecutable*, CallFrame*, ProtoCallFrame*, JSFunction*, int argumentCountIncludingThis, JSScope*, const ArgList&);

        JSValue execute(CallFrameClosure&);

        inline VM& vm();
#if ENABLE(C_LOOP)
        CLoopStack m_cloopStack;
#endif
        
#if ENABLE(COMPUTED_GOTO_OPCODES)
#if !ENABLE(LLINT_EMBEDDED_OPCODE_ID) || ASSERT_ENABLED
        static HashMap<Opcode, OpcodeID>& opcodeIDTable(); // Maps Opcode => OpcodeID.
#endif // !ENABLE(LLINT_EMBEDDED_OPCODE_ID) || ASSERT_ENABLED
#endif // ENABLE(COMPUTED_GOTO_OPCODES)
    };

    JSValue eval(JSGlobalObject*, CallFrame*, ECMAMode);

    inline CallFrame* calleeFrameForVarargs(CallFrame*, unsigned numUsedStackSlots, unsigned argumentCountIncludingThis);

    unsigned sizeOfVarargs(JSGlobalObject*, JSValue arguments, uint32_t firstVarArgOffset);
    static constexpr unsigned maxArguments = 0x10000;
    unsigned sizeFrameForVarargs(JSGlobalObject*, CallFrame*, VM&, JSValue arguments, unsigned numUsedStackSlots, uint32_t firstVarArgOffset);
    unsigned sizeFrameForForwardArguments(JSGlobalObject*, CallFrame*, VM&, unsigned numUsedStackSlots);
    void loadVarargs(JSGlobalObject*, JSValue* firstElementDest, JSValue source, uint32_t offset, uint32_t length);
    void setupVarargsFrame(JSGlobalObject*, CallFrame* execCaller, CallFrame* execCallee, JSValue arguments, uint32_t firstVarArgOffset, uint32_t length);
    void setupVarargsFrameAndSetThis(JSGlobalObject*, CallFrame* execCaller, CallFrame* execCallee, JSValue thisValue, JSValue arguments, uint32_t firstVarArgOffset, uint32_t length);
    void setupForwardArgumentsFrame(JSGlobalObject*, CallFrame* execCaller, CallFrame* execCallee, uint32_t length);
    void setupForwardArgumentsFrameAndSetThis(JSGlobalObject*, CallFrame* execCaller, CallFrame* execCallee, JSValue thisValue, uint32_t length);
    
} // namespace JSC

namespace WTF {

class PrintStream;

void printInternal(PrintStream&, JSC::DebugHookType);

} // namespace WTF
