#include <lcd/lcd.h>
#include <cstring>

LCD::LCD(Cpu& cpu)
  : screenbuffer(), regLY(0), regLYC(0),
    intHBlank(false), intVBlank(false), intOAM(false), intLYC(false),
    cpu(cpu), bgp(false), obp{Palette(true),Palette(true)},
    vram_dirty(true)
{
  screenbuffer.create(160,144);
  screenbuffer.clear();

  std::memset(vram_raw, 0, 0x2000);

  for(int i = 0; i < 256; i++)
    tilemap[i].create(8,8);
}


void LCD::write8(u16 addr, u8 data) {
  // VRAM access
  if (Range(0x8000,0x9FFF).contains(addr))
    {
      vram_raw[addr-0x8000] = data;
      vram_dirty = true;
      return;
    }

  switch(addr)
    {
    case 0xFF40: // LCDC
      // TODO
      break;
    case 0xFF41: // STAT
      intHBlank = data & IntSourceHBlank;
      intVBlank = data & IntSourceVBlank;
      intOAM = data & IntSourceOAM;
      intLYC = data & IntSourceLYC;
      break;
    case 0xFF42: // SCY
      // TODO
      break;
    case 0xFF43: // SCX
      // TODO
      break;
    case 0xFF44: // LY
      // Ignore
      break;
    case 0xFF45: // LYC
      regLYC = data;
      break;
    case 0xFF46: // DMA (OAM DMA source address)
      // TODO
      break;
    case 0xFF47: // BGP
      bgp.setRegValue(data);
      vram_dirty = true;
      break;
    case 0xFF48: // OBP0
      obp[0].setRegValue(data);
      vram_dirty = true;
      break;
    case 0xFF49: // OBP1
      obp[1].setRegValue(data);
      vram_dirty = true;
      break;
    case 0xFF4A: // WY
    case 0xFF4B: // WX
      // TODO
      break;
    }
}

u8 LCD::read8(u16 addr) {
  // VRAM access
  if (Range(0x8000,0x9FFF).contains(addr))
    return vram_raw[addr-0x8000];

  switch(addr)
    {
    case 0xFF40: // LCDC
      // TODO
      return 0x00;
    case 0xFF41: // STAT
      return (currentMode |
              (regLY == regLYC ? LycEqual : 0) |
              (intHBlank ? IntSourceHBlank : 0) |
              (intVBlank ? IntSourceVBlank : 0) |
              (intOAM ? IntSourceOAM : 0) |
              (intLYC ? IntSourceLYC : 0));
    case 0xFF42: // SCY
      // TODO
      return 0x00;
    case 0xFF43: // SCX
      // TODO
      return 0x00;
    case 0xFF44: // LY
      return regLY;
    case 0xFF45: // LYC
      return regLYC;
    case 0xFF46: // DMA (OAM DMA source address)
      // TODO
      return 0x00;
    case 0xFF47: // BGP
      return bgp.getRegValue();
    case 0xFF48: // OBP0
      return obp[0].getRegValue();
    case 0xFF49: // OBP1
      return obp[1].getRegValue();
    case 0xFF4A: // WY
    case 0xFF4B: // WY
      // TODO
      return 0x00;
    default:
      return 0xFF;
    }
}