// SPDX-FileCopyrightText: 2014 Citra Emulator Project
// SPDX-License-Identifier: GPL-2.0-or-later

#pragma once

#include <array>
#include <span>
#include <string>
#include <vector>

#include <dynarmic/interface/halt_reason.h>

#include "common/common_funcs.h"
#include "common/common_types.h"
#include "core/hardware_properties.h"

namespace Common {
struct PageTable;
}

namespace Kernel {
enum class VMAPermission : u8;
enum class DebugWatchpointType : u8;
struct DebugWatchpoint;
} // namespace Kernel

namespace Core {
class System;
class CPUInterruptHandler;

using WatchpointArray = std::array<Kernel::DebugWatchpoint, Core::Hardware::NUM_WATCHPOINTS>;

/// Generic ARMv8 CPU interface
class ARM_Interface {
public:
    YUZU_NON_COPYABLE(ARM_Interface);
    YUZU_NON_MOVEABLE(ARM_Interface);

    explicit ARM_Interface(System& system_, bool uses_wall_clock_)
        : system{system_}, uses_wall_clock{uses_wall_clock_} {}
    virtual ~ARM_Interface() = default;

    struct ThreadContext32 {
        std::array<u32, 16> cpu_registers{};
        std::array<u32, 64> extension_registers{};
        u32 cpsr{};
        u32 fpscr{};
        u32 fpexc{};
        u32 tpidr{};
    };
    // Internally within the kernel, it expects the AArch32 version of the
    // thread context to be 344 bytes in size.
    static_assert(sizeof(ThreadContext32) == 0x150);

    struct ThreadContext64 {
        std::array<u64, 31> cpu_registers{};
        u64 sp{};
        u64 pc{};
        u32 pstate{};
        std::array<u8, 4> padding{};
        std::array<u128, 32> vector_registers{};
        u32 fpcr{};
        u32 fpsr{};
        u64 tpidr{};
    };
    // Internally within the kernel, it expects the AArch64 version of the
    // thread context to be 800 bytes in size.
    static_assert(sizeof(ThreadContext64) == 0x320);

    /// Runs the CPU until an event happens
    void Run();

    /// Clear all instruction cache
    virtual void ClearInstructionCache() = 0;

    /**
     * Clear instruction cache range
     * @param addr Start address of the cache range to clear
     * @param size Size of the cache range to clear, starting at addr
     */
    virtual void InvalidateCacheRange(u64 addr, std::size_t size) = 0;

    /**
     * Notifies CPU emulation that the current page table has changed.
     *  @param new_page_table                 The new page table.
     *  @param new_address_space_size_in_bits The new usable size of the address space in bits.
     *                                        This can be either 32, 36, or 39 on official software.
     */
    virtual void PageTableChanged(Common::PageTable& new_page_table,
                                  std::size_t new_address_space_size_in_bits) = 0;

    /**
     * Set the Program Counter to an address
     * @param addr Address to set PC to
     */
    virtual void SetPC(u64 addr) = 0;

    /*
     * Get the current Program Counter
     * @return Returns current PC
     */
    virtual u64 GetPC() const = 0;

    /**
     * Get the current Stack Pointer
     * @return Returns current SP
     */
    virtual u64 GetSP() const = 0;

    /**
     * Get an ARM register
     * @param index Register index
     * @return Returns the value in the register
     */
    virtual u64 GetReg(int index) const = 0;

    /**
     * Set an ARM register
     * @param index Register index
     * @param value Value to set register to
     */
    virtual void SetReg(int index, u64 value) = 0;

    /**
     * Gets the value of a specified vector register.
     *
     * @param index The index of the vector register.
     * @return the value within the vector register.
     */
    virtual u128 GetVectorReg(int index) const = 0;

    /**
     * Sets a given value into a vector register.
     *
     * @param index The index of the vector register.
     * @param value The new value to place in the register.
     */
    virtual void SetVectorReg(int index, u128 value) = 0;

    /**
     * Get the current PSTATE register
     * @return Returns the value of the PSTATE register
     */
    virtual u32 GetPSTATE() const = 0;

    /**
     * Set the current PSTATE register
     * @param pstate Value to set PSTATE to
     */
    virtual void SetPSTATE(u32 pstate) = 0;

    virtual u64 GetTlsAddress() const = 0;

    virtual void SetTlsAddress(u64 address) = 0;

    /**
     * Gets the value within the TPIDR_EL0 (read/write software thread ID) register.
     *
     * @return the value within the register.
     */
    virtual u64 GetTPIDR_EL0() const = 0;

    /**
     * Sets a new value within the TPIDR_EL0 (read/write software thread ID) register.
     *
     * @param value The new value to place in the register.
     */
    virtual void SetTPIDR_EL0(u64 value) = 0;

    virtual void SaveContext(ThreadContext32& ctx) = 0;
    virtual void SaveContext(ThreadContext64& ctx) = 0;
    virtual void LoadContext(const ThreadContext32& ctx) = 0;
    virtual void LoadContext(const ThreadContext64& ctx) = 0;
    void LoadWatchpointArray(const WatchpointArray& wp);

    /// Clears the exclusive monitor's state.
    virtual void ClearExclusiveState() = 0;

    /// Signal an interrupt and ask the core to halt as soon as possible.
    virtual void SignalInterrupt() = 0;

    /// Clear a previous interrupt.
    virtual void ClearInterrupt() = 0;

    struct BacktraceEntry {
        std::string module;
        u64 address;
        u64 original_address;
        u64 offset;
        std::string name;
    };

    static std::vector<BacktraceEntry> GetBacktraceFromContext(System& system,
                                                               const ThreadContext32& ctx);
    static std::vector<BacktraceEntry> GetBacktraceFromContext(System& system,
                                                               const ThreadContext64& ctx);

    virtual std::vector<BacktraceEntry> GetBacktrace() const = 0;

    void LogBacktrace() const;

    static constexpr Dynarmic::HaltReason step_thread = Dynarmic::HaltReason::Step;
    static constexpr Dynarmic::HaltReason break_loop = Dynarmic::HaltReason::UserDefined2;
    static constexpr Dynarmic::HaltReason svc_call = Dynarmic::HaltReason::UserDefined3;
    static constexpr Dynarmic::HaltReason breakpoint = Dynarmic::HaltReason::UserDefined4;
    static constexpr Dynarmic::HaltReason watchpoint = Dynarmic::HaltReason::MemoryAbort;
    static constexpr Dynarmic::HaltReason no_execute = Dynarmic::HaltReason::UserDefined6;

protected:
    /// System context that this ARM interface is running under.
    System& system;
    const WatchpointArray* watchpoints;
    bool uses_wall_clock;

    static void SymbolicateBacktrace(Core::System& system, std::vector<BacktraceEntry>& out);
    const Kernel::DebugWatchpoint* MatchingWatchpoint(
        u64 addr, u64 size, Kernel::DebugWatchpointType access_type) const;

    virtual Dynarmic::HaltReason RunJit() = 0;
    virtual Dynarmic::HaltReason StepJit() = 0;
    virtual u32 GetSvcNumber() const = 0;
    virtual const Kernel::DebugWatchpoint* HaltedWatchpoint() const = 0;
    virtual void RewindBreakpointInstruction() = 0;
};

} // namespace Core
