/**
 * Copyright (c) 2026 Dominic Masters
 * 
 * This software is released under the MIT License.
 * https://opensource.org/licenses/MIT
 */

#include "dolphin.h"

void displayInitDolphin(void) {
  VIDEO_Init();
  DISPLAY.screenMode = VIDEO_GetPreferredMode(NULL);
  DISPLAY.frameBuffer[0] = MEM_K0_TO_K1(
    SYS_AllocateFramebuffer(DISPLAY.screenMode)
  );
  DISPLAY.frameBuffer[1] = MEM_K0_TO_K1(
    SYS_AllocateFramebuffer(DISPLAY.screenMode)
  );
  VIDEO_Configure(DISPLAY.screenMode);

  VIDEO_SetNextFramebuffer(DISPLAY.frameBuffer[DISPLAY.whichFrameBuffer]);
  // VIDEO_SetPostRetraceCallback(copy_buffers);
  VIDEO_SetBlack(FALSE);
  VIDEO_Flush();
  VIDEO_WaitVSync();
  if(DISPLAY.screenMode->viTVMode & VI_NON_INTERLACE) VIDEO_WaitVSync();

  DISPLAY.fifoBuffer = memalign(32, DISPLAY_FIFO_SIZE);
  memoryZero(DISPLAY.fifoBuffer, DISPLAY_FIFO_SIZE);

  GX_Init(DISPLAY.fifoBuffer, DISPLAY_FIFO_SIZE);

  // This seems to be mostly related to interlacing vs progressive
  GX_SetViewport(
    0, 0,
    DISPLAY.screenMode->fbWidth, DISPLAY.screenMode->efbHeight,
    0, 1
  );
  float_t yscale = GX_GetYScaleFactor(
    DISPLAY.screenMode->efbHeight, DISPLAY.screenMode->xfbHeight
  );
  uint32_t xfbHeight = GX_SetDispCopyYScale(yscale);
  GX_SetScissor(
    0, 0,
    DISPLAY.screenMode->fbWidth, DISPLAY.screenMode->efbHeight
  );
  GX_SetDispCopySrc(
    0, 0,
    DISPLAY.screenMode->fbWidth, DISPLAY.screenMode->efbHeight
  );
  GX_SetDispCopyDst(DISPLAY.screenMode->fbWidth, xfbHeight);
  GX_SetCopyFilter(
    DISPLAY.screenMode->aa,
    DISPLAY.screenMode->sample_pattern,
    GX_TRUE,
    DISPLAY.screenMode->vfilter
  );
  GX_SetFieldMode(
    DISPLAY.screenMode->field_rendering,
    (
      (DISPLAY.screenMode->viHeight == 2 * DISPLAY.screenMode->xfbHeight) ?
      GX_ENABLE :
      GX_DISABLE
    )
  );

  // Setup cull modes
  GX_SetCullMode(GX_CULL_NONE);
  GX_SetZMode(GX_FALSE, GX_ALWAYS, GX_FALSE);
  GX_CopyDisp(DISPLAY.frameBuffer[DISPLAY.whichFrameBuffer], GX_TRUE);
  GX_SetDispCopyGamma(GX_GM_1_0);

  GX_ClearVtxDesc();
  GX_SetVtxDesc(GX_VA_POS,  GX_INDEX16);
  GX_SetVtxDesc(GX_VA_CLR0, GX_INDEX16);
  GX_SetVtxDesc(GX_VA_TEX0, GX_INDEX16);
  GX_SetVtxAttrFmt(GX_VTXFMT0, GX_VA_POS, GX_POS_XYZ, GX_F32, 0);
  GX_SetVtxAttrFmt(GX_VTXFMT0, GX_VA_CLR0, GX_CLR_RGBA, GX_U8, 0);
  GX_SetVtxAttrFmt(GX_VTXFMT0, GX_VA_TEX0, GX_TEX_ST, GX_F32, 0);
}

void displayDolphinSwap(void) {
  GX_DrawDone();

  DISPLAY.whichFrameBuffer ^= 1;
  GX_SetZMode(GX_TRUE, GX_LEQUAL, GX_TRUE);
  GX_SetColorUpdate(GX_TRUE);
  GX_CopyDisp(DISPLAY.frameBuffer[DISPLAY.whichFrameBuffer], GX_TRUE);
  VIDEO_SetNextFramebuffer(DISPLAY.frameBuffer[DISPLAY.whichFrameBuffer]);
  VIDEO_Flush();
  VIDEO_WaitVSync();
}