// Copyright 2014 Citra Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.

#pragma once

#include <string>
#include <utility>
#include <vector>
#include "common/common_types.h"
#include "core/hle/kernel/object.h"
#include "core/hle/kernel/process.h"
#include "core/hle/result.h"

namespace Kernel {

class SharedMemory final : public Object {
public:
    explicit SharedMemory(KernelSystem& kernel);
    ~SharedMemory() override;

    std::string GetTypeName() const override {
        return "SharedMemory";
    }
    std::string GetName() const override {
        return name;
    }
    void SetName(std::string name) {
        this->name = std::move(name);
    }

    static constexpr HandleType HANDLE_TYPE = HandleType::SharedMemory;
    HandleType GetHandleType() const override {
        return HANDLE_TYPE;
    }

    /// Gets the size of the underlying memory block in bytes.
    u64 GetSize() const {
        return size;
    }

    /// Gets the linear heap physical offset
    u64 GetLinearHeapPhysicalOffset() const {
        return linear_heap_phys_offset;
    }

    /**
     * Converts the specified MemoryPermission into the equivalent VMAPermission.
     * @param permission The MemoryPermission to convert.
     */
    static VMAPermission ConvertPermissions(MemoryPermission permission);

    /**
     * Maps a shared memory block to an address in the target process' address space
     * @param target_process Process on which to map the memory block.
     * @param address Address in system memory to map shared memory block to
     * @param permissions Memory block map permissions (specified by SVC field)
     * @param other_permissions Memory block map other permissions (specified by SVC field)
     */
    ResultCode Map(Process& target_process, VAddr address, MemoryPermission permissions,
                   MemoryPermission other_permissions);

    /**
     * Unmaps a shared memory block from the specified address in system memory
     * @param target_process Process from which to unmap the memory block.
     * @param address Address in system memory where the shared memory block is mapped
     * @return Result code of the unmap operation
     */
    ResultCode Unmap(Process& target_process, VAddr address);

    /**
     * Gets a pointer to the shared memory block
     * @param offset Offset from the start of the shared memory block to get pointer
     * @return A pointer to the shared memory block from the specified offset
     */
    u8* GetPointer(u32 offset = 0);

    /**
     * Gets a constant pointer to the shared memory block
     * @param offset Offset from the start of the shared memory block to get pointer
     * @return A constant pointer to the shared memory block from the specified offset
     */
    const u8* GetPointer(u32 offset = 0) const;

private:
    /// Offset in FCRAM of the shared memory block in the linear heap if no address was specified
    /// during creation.
    PAddr linear_heap_phys_offset = 0;
    /// Backing memory for this shared memory block.
    std::vector<std::pair<u8*, u32>> backing_blocks;
    /// Size of the memory block. Page-aligned.
    u32 size = 0;
    /// Permission restrictions applied to the process which created the block.
    MemoryPermission permissions{};
    /// Permission restrictions applied to other processes mapping the block.
    MemoryPermission other_permissions{};
    /// Process that created this shared memory block.
    Process* owner_process = nullptr;
    /// Address of shared memory block in the owner process if specified.
    VAddr base_address = 0;
    /// Name of shared memory object.
    std::string name;

    struct MemoryBlockInfo {
        u32 offset;
        u32 size;
        MemoryRegion region;
        MemoryBlockInfo(u32 offset, u32 size, MemoryRegion region)
            : offset(offset), size(size), region(region) {}
    };
    std::vector<MemoryBlockInfo> holding_memory;

    friend class KernelSystem;
    KernelSystem& kernel;
};

} // namespace Kernel
