// Public NTLite hal api ABI declarations shared between kernel, drivers, and user mode.

#pragma once
// hal_api.h - HAL interface table exported as HalGetApi().
#include <stdint.h>
#include <stdbool.h>
#include <stddef.h>
#include <ntlite/status.h>

typedef struct BOOT_INFO BOOT_INFO;

typedef struct HAL_FRAMEBUFFER_INFO {
    uintptr_t Base;      // kernel virtual address of the visible framebuffer
    uint32_t  Width;
    uint32_t  Height;
    uint32_t  Stride;    // pixels per scanline
    uint32_t  Format;    // currently 0x00RRGGBB / X8R8G8B8
} HAL_FRAMEBUFFER_INFO;

typedef struct HAL_SCREEN {
    void     (*Clear)(uint32_t color);
    void     (*PutPixel)(int x, int y, uint32_t color);
    void     (*Blit)(int x, int y, int w, int h, const uint32_t* pixels);
    void     (*GetSize)(int* width, int* height);
    KSTATUS  (*GetFramebuffer)(HAL_FRAMEBUFFER_INFO* outInfo);
    void     (*Scroll)(int lines);
    void     (*PutChar)(char c, int x, int y, uint32_t fg, uint32_t bg);
    void     (*PrintChar)(char c, uint32_t fg, uint32_t bg);
    // Legacy software cursor hooks kept for early-boot/panic fallback only.
    // Normal input cursor ownership lives in ke_display.
    void     (*DrawCursor)(int x, int y);
    void     (*EraseCursor)(void);
} HAL_SCREEN;

typedef struct HAL_TIMER {
    uint64_t (*QueryTicks)(void);
    void     (*Stall)(uint32_t us);
    void     (*Isr)(void);
    uint8_t  IrqNumber;
} HAL_TIMER;


#define HAL_RTC_TIME_FLAG_VALID    0x0001u
#define HAL_RTC_TIME_FLAG_RTC      0x0002u

typedef struct HAL_RTC_TIME {
    uint16_t Year;
    uint8_t  Month;
    uint8_t  Day;
    uint8_t  Hour;
    uint8_t  Minute;
    uint8_t  Second;
    uint32_t Nanosecond;
    uint16_t Flags;
    uint16_t Reserved;
} HAL_RTC_TIME;

typedef struct HAL_RTC {
    KSTATUS (*QueryTime)(HAL_RTC_TIME* outTime);
} HAL_RTC;

typedef struct HAL_PCI {
    // Raw PCI configuration access.  Policy-level operations such as
    // enumeration, BAR decoding, interrupt discovery, and MSI programming
    // belong to pci.sys.
    uint32_t (*Read32)(uint16_t segment,
                       uint8_t bus,
                       uint8_t dev,
                       uint8_t fn,
                       uint16_t offset);

    void     (*Write32)(uint16_t segment,
                        uint8_t bus,
                        uint8_t dev,
                        uint8_t fn,
                        uint16_t offset,
                        uint32_t value);
} HAL_PCI;

typedef struct HAL_INTC {
    void (*RouteIrq)(uint8_t irq);
    void (*MaskIrq)(uint8_t irq);
    void (*UnmaskIrq)(uint8_t irq);
    void (*SendEoi)(void);
} HAL_INTC;

typedef struct HAL_POWER {
    // ACPI S5 soft-off. Disables interrupts, writes SLP_EN to PM1a/b_CNT,
    // and halts if firmware doesn't respond. Does not return.
    void (*Shutdown)(void);
} HAL_POWER;

typedef struct HAL_API {
    uint32_t     Version;
    void         *(*PhysToVirt)(uint64_t physAddr);
    HAL_SCREEN   Screen;
    HAL_TIMER    Timer;
    HAL_RTC      Rtc;
    HAL_PCI      Pci;
    HAL_INTC     Intc;
    HAL_POWER    Power;
} HAL_API;

typedef struct HAL_INIT_PARAMS {
    // Framebuffer.
    uintptr_t  FramebufferBase;
    uint32_t   FramebufferWidth;
    uint32_t   FramebufferHeight;
    uint32_t   FramebufferStride;

    // ACPI.
    uintptr_t  RsdpPhysical;

    // Memory.
    uint64_t   PhysicalWindowBase;

    // Debug.
    int        Debug;

    void*      (*AllocatePool)(size_t size);
} HAL_INIT_PARAMS;

#define HAL_API_VERSION // do not change during development

__declspec(dllexport) const HAL_API* HalGetApi(void);
__declspec(dllexport) void HalRegisterScheduler(void (*pKeSchedulerTick)(void));
__declspec(dllexport) KSTATUS HalInitialize(const HAL_INIT_PARAMS* params);