/*
  Simple DirectMedia Layer
  Copyright (C) 1997-2024 Sam Lantinga <slouken@libsdl.org>

  This software is provided 'as-is', without any express or implied
  warranty.  In no event will the authors be held liable for any damages
  arising from the use of this software.

  Permission is granted to anyone to use this software for any purpose,
  including commercial applications, and to alter it and redistribute it
  freely, subject to the following restrictions:

  1. The origin of this software must not be misrepresented; you must not
     claim that you wrote the original software. If you use this software
     in a product, an acknowledgment in the product documentation would be
     appreciated but is not required.
  2. Altered source versions must be plainly marked as such, and must not be
     misrepresented as being the original software.
  3. This notice may not be removed or altered from any source distribution.
*/

#include "SDL_internal.h"

#ifdef SDL_VIDEO_DRIVER_NGAGE

#include <SDL.h>

#include "../SDL_sysvideo.h"
#include "SDL_ngagevideo.h"
#include "SDL_ngageframebuffer_c.h"

#define NGAGE_SURFACE "NGAGE_FrameBuffer"

/* For 12 bit screen HW. Table for fast conversion from 8 bit to 12 bit
 *
 * TUint16 is enough, but using TUint32 so we can use better instruction
 * selection on ARMI.
 */
static TUint32 NGAGE_HWPalette_256_to_Screen[256];

bool GetBpp(TDisplayMode displaymode);
void DirectUpdate(SDL_VideoDevice *_this, int numrects, SDL_Rect *rects);
void DrawBackground(SDL_VideoDevice *_this);
void DirectDraw(SDL_VideoDevice *_this, int numrects, SDL_Rect *rects, TUint16 *screenBuffer);
void RedrawWindowL(SDL_VideoDevice *_this);

bool SDL_NGAGE_CreateWindowFramebuffer(SDL_VideoDevice *_this, SDL_Window *window, SDL_PixelFormat *format, void **pixels, int *pitch)
{
    SDL_VideoData *phdata = _this->internal;
    SDL_Surface *surface;
    const SDL_PixelFormat surface_format = SDL_PIXELFORMAT_XRGB4444;
    int w, h;

    // Free the old framebuffer surface
    SDL_NGAGE_DestroyWindowFramebuffer(_this, window);

    // Create a new one
    SDL_GetWindowSizeInPixels(window, &w, &h);
    surface = SDL_CreateSurface(w, h, surface_format);
    if (!surface) {
        return false;
    }

    // Save the info and return!
    SDL_SetWindowData(window, NGAGE_SURFACE, surface);
    *format = surface_format;
    *pixels = surface->pixels;
    *pitch = surface->pitch;

    // Initialise Epoc frame buffer

    TDisplayMode displayMode = phdata->NGAGE_WsScreen->DisplayMode();

    TScreenInfoV01 screenInfo;
    TPckg<TScreenInfoV01> sInfo(screenInfo);
    UserSvr::ScreenInfo(sInfo);

    phdata->NGAGE_ScreenSize = screenInfo.iScreenSize;
    phdata->NGAGE_DisplayMode = displayMode;
    phdata->NGAGE_HasFrameBuffer = screenInfo.iScreenAddressValid;
    phdata->NGAGE_FrameBuffer = phdata->NGAGE_HasFrameBuffer ? (TUint8 *)screenInfo.iScreenAddress : NULL;
    phdata->NGAGE_BytesPerPixel = ((GetBpp(displayMode) - 1) / 8) + 1;

    phdata->NGAGE_BytesPerScanLine = screenInfo.iScreenSize.iWidth * phdata->NGAGE_BytesPerPixel;
    phdata->NGAGE_BytesPerScreen = phdata->NGAGE_BytesPerScanLine * phdata->NGAGE_ScreenSize.iHeight;

    SDL_Log("Screen width        %d", screenInfo.iScreenSize.iWidth);
    SDL_Log("Screen height       %d", screenInfo.iScreenSize.iHeight);
    SDL_Log("Screen dmode        %d", displayMode);
    SDL_Log("Screen valid        %d", screenInfo.iScreenAddressValid);

    SDL_Log("Bytes per pixel     %d", phdata->NGAGE_BytesPerPixel);
    SDL_Log("Bytes per scan line %d", phdata->NGAGE_BytesPerScanLine);
    SDL_Log("Bytes per screen    %d", phdata->NGAGE_BytesPerScreen);

    /* It seems that in SA1100 machines for 8bpp displays there is a 512
     * palette table at the beginning of the frame buffer.
     *
     * In 12 bpp machines the table has 16 entries.
     */
    if (phdata->NGAGE_HasFrameBuffer && GetBpp(displayMode) == 8) {
        phdata->NGAGE_FrameBuffer += 512;
    } else {
        phdata->NGAGE_FrameBuffer += 32;
    }
#if 0
    if (phdata->NGAGE_HasFrameBuffer && GetBpp(displayMode) == 12) {
        phdata->NGAGE_FrameBuffer += 16 * 2;
    }
    if (phdata->NGAGE_HasFrameBuffer && GetBpp(displayMode) == 16) {
        phdata->NGAGE_FrameBuffer += 16 * 2;
    }
#endif

    // Get draw device for updating the screen
    TScreenInfoV01 screenInfo2;

    NGAGE_Runtime::GetScreenInfo(screenInfo2);

    TRAPD(status, phdata->NGAGE_DrawDevice = CFbsDrawDevice::NewScreenDeviceL(screenInfo2, displayMode));
    User::LeaveIfError(status);

    // Activate events for me
    phdata->NGAGE_WsEventStatus = KRequestPending;
    phdata->NGAGE_WsSession.EventReady(&phdata->NGAGE_WsEventStatus);

    SDL_Log("SDL:WsEventStatus");
    User::WaitForRequest(phdata->NGAGE_WsEventStatus);

    phdata->NGAGE_RedrawEventStatus = KRequestPending;
    phdata->NGAGE_WsSession.RedrawReady(&phdata->NGAGE_RedrawEventStatus);

    SDL_Log("SDL:RedrawEventStatus");
    User::WaitForRequest(phdata->NGAGE_RedrawEventStatus);

    phdata->NGAGE_WsWindow.PointerFilter(EPointerFilterDrag, 0);

    phdata->NGAGE_ScreenOffset = TPoint(0, 0);

    SDL_Log("SDL:DrawBackground");
    DrawBackground(_this); // Clear screen

    return true;
}

bool SDL_NGAGE_UpdateWindowFramebuffer(SDL_VideoDevice *_this, SDL_Window *window, const SDL_Rect *rects, int numrects)
{
    DirectUpdate(_this, numrects, (SDL_Rect *)rects);
    return true;
}

void SDL_NGAGE_DestroyWindowFramebuffer(SDL_VideoDevice *_this, SDL_Window *window)
{
    SDL_Surface *surface;

    surface = (SDL_Surface *)SDL_SetWindowData(window, NGAGE_SURFACE, NULL);
    SDL_DestroySurface(surface);
}

/*****************************************************************************/
// Runtime
/*****************************************************************************/

#include <e32svr.h>
#include <hal_data.h>
#include <hal.h>

EXPORT_C void NGAGE_Runtime::GetScreenInfo(TScreenInfoV01 &screenInfo2)
{
    TPckg<TScreenInfoV01> sInfo2(screenInfo2);
    UserSvr::ScreenInfo(sInfo2);
}

/*****************************************************************************/
// Internal
/*****************************************************************************/

bool GetBpp(TDisplayMode displaymode)
{
    return TDisplayModeUtils::NumDisplayModeBitsPerPixel(displaymode);
}

void DrawBackground(SDL_VideoDevice *_this)
{
    SDL_VideoData *phdata = _this->internal;
    // Draw background
    TUint16 *screenBuffer = (TUint16 *)phdata->NGAGE_FrameBuffer;
    // Draw black background
    Mem::FillZ(screenBuffer, phdata->NGAGE_BytesPerScreen);
}

void DirectDraw(SDL_VideoDevice *_this, int numrects, SDL_Rect *rects, TUint16 *screenBuffer)
{
    SDL_VideoData *phdata = _this->internal;
    SDL_Surface *screen = (SDL_Surface *)SDL_GetWindowData(_this->windows, NGAGE_SURFACE);

    TInt i;

    TDisplayMode displayMode = phdata->NGAGE_DisplayMode;
    const TInt sourceNumBytesPerPixel = ((GetBpp(displayMode) - 1) / 8) + 1;

    const TPoint fixedOffset = phdata->NGAGE_ScreenOffset;
    const TInt screenW = screen->w;
    const TInt screenH = screen->h;
    const TInt sourceScanlineLength = screenW;
    const TInt targetScanlineLength = phdata->NGAGE_ScreenSize.iWidth;

    // Render the rectangles in the list

    for (i = 0; i < numrects; ++i) {
        const SDL_Rect &currentRect = rects[i];
        SDL_Rect rect2;
        rect2.x = currentRect.x;
        rect2.y = currentRect.y;
        rect2.w = currentRect.w;
        rect2.h = currentRect.h;

        if (rect2.w <= 0 || rect2.h <= 0) /* Sanity check */ {
            continue;
        }

        // All variables are measured in pixels

        // Check rects validity, i.e. upper and lower bounds
        TInt maxX = Min(screenW - 1, rect2.x + rect2.w - 1);
        TInt maxY = Min(screenH - 1, rect2.y + rect2.h - 1);
        if (maxX < 0 || maxY < 0) /* sanity check */ {
            continue;
        }
        // Clip from bottom

        maxY = Min(maxY, phdata->NGAGE_ScreenSize.iHeight - 1);
        // TODO: Clip from the right side

        const TInt sourceRectWidth = maxX - rect2.x + 1;
        const TInt sourceRectWidthInBytes = sourceRectWidth * sourceNumBytesPerPixel;
        const TInt sourceRectHeight = maxY - rect2.y + 1;
        const TInt sourceStartOffset = rect2.x + rect2.y * sourceScanlineLength;
        const TUint skipValue = 1; // 1 = No skip

        TInt targetStartOffset = fixedOffset.iX + rect2.x + (fixedOffset.iY + rect2.y) * targetScanlineLength;

        switch (screen->format->bits_per_pixel) {
        case 12:
        {
            TUint16 *bitmapLine = (TUint16 *)screen->pixels + sourceStartOffset;
            TUint16 *screenMemory = screenBuffer + targetStartOffset;

            if (skipValue == 1) {
                for (TInt y = 0; y < sourceRectHeight; y++) {
                    Mem::Copy(screenMemory, bitmapLine, sourceRectWidthInBytes);
                    bitmapLine += sourceScanlineLength;
                    screenMemory += targetScanlineLength;
                }
            } else {
                for (TInt y = 0; y < sourceRectHeight; y++) {
                    TUint16 *bitmapPos = bitmapLine;             // 2 bytes per pixel
                    TUint16 *screenMemoryLinePos = screenMemory; // 2 bytes per pixel
                    for (TInt x = 0; x < sourceRectWidth; x++) {
                        __ASSERT_DEBUG(screenMemory < (screenBuffer + phdata->NGAGE_ScreenSize.iWidth * phdata->NGAGE_ScreenSize.iHeight), User::Panic(_L("SDL"), KErrCorrupt));
                        __ASSERT_DEBUG(screenMemory >= screenBuffer, User::Panic(_L("SDL"), KErrCorrupt));
                        __ASSERT_DEBUG(bitmapLine < ((TUint16 *)screen->pixels + (screen->w * screen->h)), User::Panic(_L("SDL"), KErrCorrupt));
                        __ASSERT_DEBUG(bitmapLine >= (TUint16 *)screen->pixels, User::Panic(_L("SDL"), KErrCorrupt));

                        *screenMemoryLinePos++ = *bitmapPos;
                        bitmapPos += skipValue;
                    }
                    bitmapLine += sourceScanlineLength;
                    screenMemory += targetScanlineLength;
                }
            }
        } break;
        // 256 color paletted mode: 8 bpp --> 12 bpp
        default:
        {
            if (phdata->NGAGE_BytesPerPixel <= 2) {
                TUint8 *bitmapLine = (TUint8 *)screen->pixels + sourceStartOffset;
                TUint16 *screenMemory = screenBuffer + targetStartOffset;

                for (TInt y = 0; y < sourceRectHeight; y++) {
                    TUint8 *bitmapPos = bitmapLine;              // 1 byte per pixel
                    TUint16 *screenMemoryLinePos = screenMemory; // 2 bytes per pixel
                    // Convert each pixel from 256 palette to 4k color values
                    for (TInt x = 0; x < sourceRectWidth; x++) {
                        __ASSERT_DEBUG(screenMemoryLinePos < (screenBuffer + (phdata->NGAGE_ScreenSize.iWidth * phdata->NGAGE_ScreenSize.iHeight)), User::Panic(_L("SDL"), KErrCorrupt));
                        __ASSERT_DEBUG(screenMemoryLinePos >= screenBuffer, User::Panic(_L("SDL"), KErrCorrupt));
                        __ASSERT_DEBUG(bitmapPos < ((TUint8 *)screen->pixels + (screen->w * screen->h)), User::Panic(_L("SDL"), KErrCorrupt));
                        __ASSERT_DEBUG(bitmapPos >= (TUint8 *)screen->pixels, User::Panic(_L("SDL"), KErrCorrupt));
                        *screenMemoryLinePos++ = NGAGE_HWPalette_256_to_Screen[*bitmapPos++];
                    }
                    bitmapLine += sourceScanlineLength;
                    screenMemory += targetScanlineLength;
                }
            } else {
                TUint8 *bitmapLine = (TUint8 *)screen->pixels + sourceStartOffset;
                TUint32 *screenMemory = reinterpret_cast<TUint32 *>(screenBuffer + targetStartOffset);
                for (TInt y = 0; y < sourceRectHeight; y++) {
                    TUint8 *bitmapPos = bitmapLine;              // 1 byte per pixel
                    TUint32 *screenMemoryLinePos = screenMemory; // 2 bytes per pixel
                    // Convert each pixel from 256 palette to 4k color values
                    for (TInt x = 0; x < sourceRectWidth; x++) {
                        __ASSERT_DEBUG(screenMemoryLinePos < (reinterpret_cast<TUint32 *>(screenBuffer) + (phdata->NGAGE_ScreenSize.iWidth * phdata->NGAGE_ScreenSize.iHeight)), User::Panic(_L("SDL"), KErrCorrupt));
                        __ASSERT_DEBUG(screenMemoryLinePos >= reinterpret_cast<TUint32 *>(screenBuffer), User::Panic(_L("SDL"), KErrCorrupt));
                        __ASSERT_DEBUG(bitmapPos < ((TUint8 *)screen->pixels + (screen->w * screen->h)), User::Panic(_L("SDL"), KErrCorrupt));
                        __ASSERT_DEBUG(bitmapPos >= (TUint8 *)screen->pixels, User::Panic(_L("SDL"), KErrCorrupt));
                        *screenMemoryLinePos++ = NGAGE_HWPalette_256_to_Screen[*bitmapPos++];
                    }
                    bitmapLine += sourceScanlineLength;
                    screenMemory += targetScanlineLength;
                }
            }
        }
        }
    }
}

void DirectUpdate(SDL_VideoDevice *_this, int numrects, SDL_Rect *rects)
{
    SDL_VideoData *phdata = _this->internal;

    if (!phdata->NGAGE_IsWindowFocused) {
        SDL_PauseAudio(1);
        SDL_Delay(1000);
        return;
    }

    SDL_PauseAudio(0);

    TUint16 *screenBuffer = (TUint16 *)phdata->NGAGE_FrameBuffer;

#if 0
    if (phdata->NGAGE_ScreenOrientation == CFbsBitGc::EGraphicsOrientationRotated270) {
        // ...
    } else
#endif
    {
        DirectDraw(_this, numrects, rects, screenBuffer);
    }

    for (int i = 0; i < numrects; ++i) {
        TInt aAx = rects[i].x;
        TInt aAy = rects[i].y;
        TInt aBx = rects[i].w;
        TInt aBy = rects[i].h;
        TRect rect2 = TRect(aAx, aAy, aBx, aBy);

        phdata->NGAGE_DrawDevice->UpdateRegion(rect2); // Should we update rects parameter area only?
        phdata->NGAGE_DrawDevice->Update();
    }
}

void RedrawWindowL(SDL_VideoDevice *_this)
{
    SDL_VideoData *phdata = _this->internal;
    SDL_Surface *screen = (SDL_Surface *)SDL_GetWindowData(_this->windows, NGAGE_SURFACE);

    int w = screen->w;
    int h = screen->h;
    if (phdata->NGAGE_ScreenOrientation == CFbsBitGc::EGraphicsOrientationRotated270) {
        w = screen->h;
        h = screen->w;
    }
    if ((w < phdata->NGAGE_ScreenSize.iWidth) || (h < phdata->NGAGE_ScreenSize.iHeight)) {
        DrawBackground(_this);
    }

    // Tell the system that something has been drawn
    TRect rect = TRect(phdata->NGAGE_WsWindow.Size());
    phdata->NGAGE_WsWindow.Invalidate(rect);

    // Draw current buffer
    SDL_Rect fullScreen;
    fullScreen.x = 0;
    fullScreen.y = 0;
    fullScreen.w = screen->w;
    fullScreen.h = screen->h;
    DirectUpdate(_this, 1, &fullScreen);
}

#endif // SDL_VIDEO_DRIVER_NGAGE
