/*
   fifo_demo1 ARM9 Code 
   Chris Double (chris.double@double.co.nz)
   http://www.double.co.nz/nintendo_ds
*/

#include <nds.h>
#include "nds/arm9/console.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "fifo.h"
#include "transfer.h"

uint32 arm9_recv = 0;

void on_irq() 
{	
  if(REG_IF & IRQ_VBLANK) {
    // Clear screen
    printf("\x1b[2J");
    printf("FIFO Demo Program\n\n");

    printf("ARM9 Fifo Registers:\n");
    printf("REG_IPCFIFOCNT:   %x\n", REG_IPCFIFOCNT);
    printf("REG_IPCFIFORECV:  %x\n", arm9_recv);
    
    printf("ARM7 Fifo Registers:\n");
    printf("REG_IPCFIFOCNT:   %x\n", arm7_fifo->cnt);
    printf("REG_IPCFIFORECV:  %x\n", arm7_fifo->recv);

    // Tell the DS we handled the VBLANK interrupt
    VBLANK_INTR_WAIT_FLAGS |= IRQ_VBLANK;
    REG_IF |= IRQ_VBLANK;
  }
  else {
    // Ignore all other interrupts
    REG_IF = REG_IF;
  }
}

void InitInterruptHandler()
{
  REG_IME = 0;
  IRQ_HANDLER = on_irq;
  REG_IE = IRQ_VBLANK;
  REG_IF = ~0;
  DISP_SR = DISP_VBLANK_IRQ;
  REG_IME = 1;
}

int main(void)
{
  powerON(POWER_ALL);  
  videoSetMode(MODE_0_2D | DISPLAY_BG0_ACTIVE);
  vramSetBankA(VRAM_A_MAIN_BG);
  BG0_CR = BG_MAP_BASE(31);
  BG_PALETTE[255] = RGB15(31,31,31);
  lcdSwap();
  InitInterruptHandler();
  consoleInitDefault((u16*)SCREEN_BASE_BLOCK(31), (u16*)CHAR_BASE_BLOCK(0), 16);
  CommandInit();

  while(1) {
    swiWaitForVBlank();
    scanKeys();
    // ARM9 Keys
    if((keysHeld() & KEY_R) && (keysDown() & KEY_UP)) {
      REG_IPCFIFOCNT = IPC_FIFO_ENABLE | IPC_FIFO_SEND_CLEAR;
    }
    if((keysHeld() & KEY_R) && (keysDown() & KEY_RIGHT)) {
      static int count = 0;
      REG_IPCFIFOSEND = ++count;
    }
    if((keysHeld() & KEY_R) && (keysDown() & KEY_DOWN)) {
      arm9_recv = REG_IPCFIFORECV;
    }

    // ARM7 Keys
    if((keysHeld() & KEY_L) && (keysDown() & KEY_UP)) {
      CommandFIFOInit();
    }
    if((keysHeld() & KEY_L) && (keysDown() & KEY_RIGHT)) {
      CommandFIFOSend();
    }
    if((keysHeld() & KEY_L) && (keysDown() & KEY_DOWN)) {
      CommandFIFORecv();
    }
  }

  return 0;
}