/*  term.c - terminal routines */

#include <os.h>
#include "ascii8x8.h"


static int row = 0;
static int col = 0;
static unsigned *scr_ptr;
static int serial = 0;

unsigned long ByteSwap(unsigned long val)  // http://www.ethernut.de/en/documents/arm-inline-asm.html
{
asm volatile (
        "eor     r3, %1, %1, ror #16\n\t"
        "bic     r3, r3, #0x00FF0000\n\t"
        "mov     %0, %1, ror #8\n\t"
        "eor     %0, %0, r3, lsr #8"
        : "=r" (val)
        : "0"(val)
        : "r3" 
);
return val;
} 

int setIOmode(int cmd){
  if (cmd == -1) return serial;
  serial =  cmd;  // set mode: 0 == console , 1 == rs232
  return cmd;
}

int drawchar(int ch){
 int i;
 for(i=0;i<8;++i){
  scr_ptr = (unsigned*)( SCREEN_BASE_ADDRESS + 0x500*row + 4*col +i*0xA0);
  *scr_ptr = ByteSwap(lowerascii[ch*8 + i]);
 }
 ++col;
 return 0;
}


void scrollregion(int rows, int cursorX, int cursorY){  // number of rows to scroll - usually 1
        int y,w;
        memmove(SCREEN_BASE_ADDRESS, SCREEN_BASE_ADDRESS + 1280*rows, 38400 - 1280*rows);
        for(y=29-rows+1;y<=29;++y){   // clear the scrolled in region  
         row = y; col = 0; 
         for(w=0;w<40;++w)drawchar(0x20); 
        }      
       row = cursorY; col = cursorX;  // move cursor when done
}

int drawstring(char *s){
 int i;
 i = 0;
 char ch;
 if(serial){
  log_rs232_v(s);
  return 1;
 }
 while( (char) *(s+i) != '\0'){
  ch = (char) *(s+i);
  if(ch == '\n' || ch == '\r'){
   ++row; col = 0;
   if (row > 29) 
         scrollregion(1,0,29);
   ++i;  
   continue;
  }
  drawchar((int) ch);
  if(col >= 40){
   ++row; col = 0;
  }
  if (row > 29) 
         scrollregion(1,0,29);
  ++i;
 }
 return i;
}

void ShowCursor(void) {
     char pa[0x104];
      if(serial == 1){
         getcwd(pa,0x101);
         log_rs232_v(pa);
         log_rs232_v(">");
         return ;
       } else {
         drawchar(0x1f);  
         --col;
       }
}


unsigned getch(void) {
	event *e;
        unsigned now, skey;
        e = (event*)EVENT;      
	do {
           idle(); //((void(*)(void))0xd0078128)();
           now = e->timestamp;
           TCC_Task_Sleep(0x3);  // give OS 3 ticks  timer updates, ...
        } while (e->type != 0x8 || e->timestamp == now );
	skey = e->ascii | e->key << 8 | e->modifier << 16;       
        return skey;
}

int rs232_gets(char *buffer, int bufsize){
 int index = 0;
 int ch;
 char pckey[4];
 pckey[0] = '\0';pckey[1] = '\0';pckey[2] = '\0';pckey[3] = '\0';
  do{ 
   ch = SDC_Data_Ready(log_rs232_param2_); 
   if (ch == 0 ){
    TCC_Task_Sleep(2);
    continue; // nothing pressed
   }
   ch = SDC_Get_Char(log_rs232_param2_);
   if(ch == 0xd || ch == 0xa){  // return or enter pressed
    log_rs232_v("\n"); // echo the key
    break;
   }
   if(ch == 0x8 && index > 0){  // backspace pressed
    --index;
    *(buffer + index) = '\0';
    log_rs232_v("\b"); // move cursor back for rubout
    log_rs232_v(" "); // rubout unwanted char
    log_rs232_v("\b"); // move cursor back
    continue;
   } 
   *(buffer + index) = (char)ch;
   ++index; 
   pckey[0] = (char)ch;
   log_rs232_v(pckey); // echo the key
  }while(index < bufsize);
  if (index >= bufsize) index = bufsize-1; // should be ==
  *(buffer + index) = '\0'; 
  return index;
}

char *gets(char *buf) {
	char ch,chs[4];
        int len, key;
        buf[0] = '\0';
        chs[0] = '\0'; chs[1] = '\0'; chs[2] = '\0'; chs[3] = '\0';
        if(serial){
         rs232_gets(buf,40);
         return buf;
        }
	do {
          key = getch(); 
	  ch = (char)(key & 0xff);
          if (ch == '\b' && strlen(buf) > 0 && col > 0){  // backspace - rubout
           drawstring("\x01"); // rubout the cursor
           --col; --col;
           drawstring("\x1F"); // overwrite the character with the cursor
           --col;
           len = strlen(buf);
           buf[--len] = '\0'; // delete last char in buffer
           continue;
          }
          if ((int)ch >= 0x20 && (int)ch < 0x80){  // printable ascii char
           chs[0] = ch;
           drawchar((int) ch); // echo the key
           if(col >= 40){
            ++row;
            col = 0;
           }
           if (row > 29) scrollregion(1,0,29); // scroll screen one line if necessary
           ShowCursor();  
           strcat(buf,chs);
           continue;
          }
	} while (ch != '\n' && ch != '\r' && ch != (char)27);   // return key(10) or Enter key(13) or ESC key(27)
        drawchar(0x20); // erase cursor
        col = 0; ++row;    // advance to next line becuse of carriage return
        if (row > 29){
         scrollregion(1,0,29);  // scroll one line up if cursor past bottom of screen
        } 
        ShowCursor();       
        if ((int)ch ==27){strcat(buf,"\x1b");} // concat ESC if pressed 
	return buf;
}


void clearscreen(void){
        memset(SCREEN_BASE_ADDRESS, 0xFF, SCREEN_BYTES_SIZE);
        row = 0; col = 0; 
        ShowCursor(); 
}