/* ZLock by Levak 13/02/12 */

#include <os.h>
#include "libndls.h"
#define MAXLEN 10
#define QUOTE_X(t)#t
#define QUOTE(t)QUOTE_X(t)

static char *title = "ZLock says";
static char *errorUninst = "ZLock Manager is not installed yet.";
static char *successUninst = "ZLock successfuly deleted config file !";
static char *welcome1Msg = "Hi, welcome to ZLock !\nThis program lets you protect your TI-Nspire with a digit code password !\nPRESS ENTER TO CONTINUE\nLevak";
static char *welcome2Msg = "We are going to configure ZLock.\nLet's enter a password of maximum " QUOTE(MAXLEN) " characters.\nPRESS ENTER TO CONTINUE";
static char *welcome3Msg = "Congratulations !\nZLock is now set up, test it !\nTip : you can put ZLock in ndless/startup/ so that it will protect your TI-Nspire on startup !\n\nVisit http://tiplanet.org/ for more TI-Nspire programs !";
static char *welcomeCanceled = "Setup Canceled.";
static char *confirmUninst = "Do you really want to uninstall ZLock ?";
static char *yes = "Yes";
static char *no = "No";
static char *wrongPass = "Wrong Password, try again.\nAttempts remaining : 0";
static char *floodAttempt = "Flood Attempt detected.\nWait 10 seconds to try again.";

#define lock_width 12
#define lock_height 12
static unsigned char lock[lock_width][lock_height] = {
{15,15,15,0,0,0,0,0,0,15,15,15},     {15,15,0,0,7,7,7,7,0,0,15,15},
{15,15,0,12,15,15,15,15,12,0,15,15}, {15,15,0,12,15,15,15,15,12,0,15,15},
{15,0,0,0,0,0,0,0,0,0,0,15},         {15,0,7,12,15,15,15,15,12,7,0,15},
{15,0,7,12,15,15,15,15,12,7,0,15},   {15,0,7,12,15,0,0,15,12,7,0,15},
{15,0,7,12,15,0,0,15,12,7,0,15},     {15,0,7,12,15,15,15,15,12,7,0,15},
{15,0,7,12,7,7,7,7,12,7,0,15},       {15,15,15,15,15,15,15,15,15,15,15,15}
};

static unsigned short* p_timer = (unsigned short*) 0x90090000;
static unsigned short last_timer = 0;
static unsigned int* p_contrast = (unsigned int*) 0x900F0020;
static unsigned int contrast;
static unsigned int timeout = 5; /* in seconds */

/* From particles by ExtendeD, mdified */
inline void setPixel(int x, int y, int r, int g, int b) {
  if(lcd_isincolor()) { /* Inverted color for CX since it is ugly and sharpen */
    unsigned short* p = (unsigned short*)(SCREEN_BASE_ADDRESS + (x << 1) + (y << 9) + (y << 7));
    *p = ((255-r) >> 3) | (((255-g) >> 2) << 5) | (((255-b) >> 3) << 11);
  }
  else {
    unsigned char* p = (unsigned char*)(SCREEN_BASE_ADDRESS  + ((x >> 1) + (y << 7) + (y << 5)));
    *p = (x & 1) ? ((*p & 0xF0) | r) : ((*p & 0x0F) | (r << 4));
  }
}
void clrscr(void) {
  if(lcd_isincolor())
    memset(SCREEN_BASE_ADDRESS, 0x00, SCREEN_BYTES_SIZE);
  else
    memset(SCREEN_BASE_ADDRESS, 0xFF, SCREEN_BYTES_SIZE);
}
/* End of particles */

void drawLock(void) {
  unsigned int i, j;
  for(i = 0; i < lock_width; i ++)
    for(j = 0; j < lock_height; j ++){
      unsigned char v =  lock[j][i] * 16;
      setPixel(i, j, v, v, v);
    }
}

void fillCircle(int x, int y, int r) {
  int i, j;
  for(i = -r; i < r; ++i)
    for(j = -r; j < r; ++j) {
      int v = i*i + j*j - r*r;
      if(v < 0 && v > -40 )
	setPixel(x+i, y+j, 255, 255, 255);
      else if(v < 0)
	setPixel(x+i, y+j, 0, 0, 0);
    }
}

void fillRect(int x1, int y1, int x2, int y2) {
  int i, j;
  for(i = x1; i < x2; ++i)
    for(j = y1; j < y2; ++j)
      setPixel(i, j, 255, 255, 255);
}

void drawRect(int x1, int y1, int x2, int y2) {
  int i, j;
  int margin = 2;
  for(i = x1; i < x2; ++i)
    for(j = y1; j < y2; ++j)
      if(i < x1 + margin || i > x2 - margin 
      || j < y1 + margin || j > y2 - margin)
	setPixel(i, j, 0, 0, 0);
}

/* Non-bloking fadeDown of the backlight */
BOOL fadeDown(void) {
  printf("%x fadeDown\n", *p_contrast);
  return (is_cx && --*p_contrast > 0x100) 
     || (!is_cx && --*p_contrast > 0x6B);
}

/* Non-bloking fadeUp of the backlight */
BOOL fadeUp(void) {
  printf("%x fadeUp\n", *p_contrast);
  return (is_cx && ++*p_contrast < contrast) 
     || (!is_cx && ++*p_contrast < contrast);
}

/* Blocking fadeOut of the backlight */
void fadeOut(int ms) {
  while(fadeDown())
    sleep(ms);
}

/* Blocking fadeIn of the backlight */
void fadeIn(int ms) {
  while(fadeUp())
    sleep(ms);
}

char request_char(void) {
  char key = 0;
  BOOL idle_mode = FALSE;
  last_timer = *p_timer; /* reset timer */
  wait_no_key_pressed();
  while (key == 0) {
    while(!any_key_pressed()) {
      /* if timer has expired, bright down the screen */
      if(!idle_mode && *p_timer >= last_timer + timeout) {
	idle_mode = !fadeDown();
	sleep(50);
      }
      else if(idle_mode) {
	sleep(500);
      }
    }
    idle_mode = FALSE;
    *p_contrast = contrast; /* Release contrast */
    if(isKeyPressed(KEY_NSPIRE_0)) key = '0';
    if(isKeyPressed(KEY_NSPIRE_1)) key = '1';
    if(isKeyPressed(KEY_NSPIRE_2)) key = '2';
    if(isKeyPressed(KEY_NSPIRE_3)) key = '3';
    if(isKeyPressed(KEY_NSPIRE_4)) key = '4';
    if(isKeyPressed(KEY_NSPIRE_5)) key = '5';
    if(isKeyPressed(KEY_NSPIRE_6)) key = '6';
    if(isKeyPressed(KEY_NSPIRE_7)) key = '7';
    if(isKeyPressed(KEY_NSPIRE_8)) key = '8';
    if(isKeyPressed(KEY_NSPIRE_9)) key = '9';
    if(isKeyPressed(KEY_NSPIRE_A)) key = 'A';
    if(isKeyPressed(KEY_NSPIRE_B)) key = 'B';
    if(isKeyPressed(KEY_NSPIRE_C)) key = 'C';
    if(isKeyPressed(KEY_NSPIRE_D)) key = 'D';
    if(isKeyPressed(KEY_NSPIRE_E)) key = 'E';
    if(isKeyPressed(KEY_NSPIRE_F)) key = 'F';
    if(isKeyPressed(KEY_NSPIRE_G)) key = 'G';
    if(isKeyPressed(KEY_NSPIRE_H)) key = 'H';
    if(isKeyPressed(KEY_NSPIRE_I)) key = 'I';
    if(isKeyPressed(KEY_NSPIRE_J)) key = 'J';
    if(isKeyPressed(KEY_NSPIRE_K)) key = 'K';
    if(isKeyPressed(KEY_NSPIRE_L)) key = 'L';
    if(isKeyPressed(KEY_NSPIRE_M)) key = 'M';
    if(isKeyPressed(KEY_NSPIRE_N)) key = 'N';
    if(isKeyPressed(KEY_NSPIRE_O)) key = 'O';
    if(isKeyPressed(KEY_NSPIRE_P)) key = 'P';
    if(isKeyPressed(KEY_NSPIRE_Q)) key = 'Q';
    if(isKeyPressed(KEY_NSPIRE_R)) key = 'R';
    if(isKeyPressed(KEY_NSPIRE_S)) key = 'S';
    if(isKeyPressed(KEY_NSPIRE_T)) key = 'T';
    if(isKeyPressed(KEY_NSPIRE_U)) key = 'U';
    if(isKeyPressed(KEY_NSPIRE_V)) key = 'V';
    if(isKeyPressed(KEY_NSPIRE_W)) key = 'W';
    if(isKeyPressed(KEY_NSPIRE_X)) key = 'X';
    if(isKeyPressed(KEY_NSPIRE_Y)) key = 'Y';
    if(isKeyPressed(KEY_NSPIRE_Z)) key = 'Z';
    if(isKeyPressed(KEY_NSPIRE_ESC)) key = 1;
    if(isKeyPressed(KEY_NSPIRE_DEL)) key = 2;
    if(isKeyPressed(KEY_NSPIRE_ENTER)) key = 3;
    wait_no_key_pressed();
    last_timer = *p_timer; /* reset timer */
  }
  return key;
}

int request_pwd(char *password, int maxlen, BOOL init) {
  int len = 0;
  char key = 0;
  int i;
  int r = 10;
  int offset = 10;
  int size = (2*r + offset)/2;
  for(i = 0; i < maxlen; ++i)
    password[i] = 0;

  /* Main Loop */
  while (len < maxlen && key != 3){ /* Enterkey */
    if(init)
      drawRect(150 - maxlen*size + offset, 220-1.5*r, 
	       150 + maxlen*size + offset, 220+1.5*r);

    fillRect(150 - maxlen*size + offset+2, 220-1.5*r+2, 
	     150 + maxlen*size + offset-2, 220+1.5*r-2);
    
    drawLock();
    for(i = 0; i < len; ++i)
      fillCircle(140 - (2*i - len)*size + offset/2, 220, r);
    
    key = request_char();

    if (key >= '0' && key <= '9' || key >= 'A' && key <= 'Z')
      password[len++] = key;
    else if (key == 2 && len > 0) /* Backspace */
      password[--len] = 0;
    else if (key == 1) /* Esc key */
      return 1;
  }
  return 0;
}

void zlock(char* config_path) {
  /* Extra screen buffer */
  char *sbuffer = malloc(SCREEN_BYTES_SIZE);
  memcpy(sbuffer, SCREEN_BASE_ADDRESS, SCREEN_BYTES_SIZE);

  char password[MAXLEN+1];
  password[MAXLEN] = 0;
  contrast = *p_contrast; /* Save user contrast */

  FILE *config; /* Contains password */
  config = fopen (config_path, "r");
  if (config != NULL) {
    char realpass[MAXLEN+1];
    int i;
    for(i = 0; i < MAXLEN; ++i)
      realpass[i] = 0;
    fread(realpass, sizeof(char), MAXLEN, config);
    fclose(config);
    int attempts = 0;
    fadeOut(20);
    clrscr();
    drawLock();
    fadeIn(20);
    while((request_pwd(password, MAXLEN, FALSE) != 0 
	   || strcmp(password, realpass)) 
	  && !(++attempts > 2)) {
      /* If password doesn't match or if attempt number exceds 3 */
      wrongPass[strlen(wrongPass)-1] = '0' + (3 - attempts);
      sleep(2000);
      show_msgbox(title, wrongPass);
      clrscr();
      drawLock();
    }
    if(attempts < 3) {
      fadeOut(10);
      memcpy(SCREEN_BASE_ADDRESS, sbuffer, SCREEN_BYTES_SIZE);
      fadeIn(10);
      puts("ok");
    }
    else {
      show_msgbox(title, floodAttempt);
      clrscr();
      drawLock();
      sleep(10000);
      zlock(config_path);
    }
  }
  else if(!nl_isstartup()) {
    /* Welcome, First use */
    show_msgbox(title, welcome1Msg);

    /* Saving password */
    show_msgbox(title, welcome2Msg);
    fadeOut(20);
    clrscr();
    fadeIn(20);
    if(request_pwd(password, MAXLEN, TRUE) == 0) {
      fadeOut(20);
      memcpy(SCREEN_BASE_ADDRESS, sbuffer, SCREEN_BYTES_SIZE);
      fadeIn(20);
      config = fopen (config_path, "w");
      fputs (password, config);
      fclose (config);
      show_msgbox(title, welcome3Msg);
    }
    else { /* Canceled setup */
      fadeOut(20);
      memcpy(SCREEN_BASE_ADDRESS, sbuffer, SCREEN_BYTES_SIZE);
      fadeIn(20);
      show_msgbox(title, welcomeCanceled);
    }
  }
  /* Restore user defined contrast */
  *p_contrast = contrast;
  free(sbuffer);
}

int main(int argc, char* argv[]) {

  if(argc < 1) return 0;

  char *config_path = "/documents/config.zlock";

  int len = strlen(argv[0]);
  char path[len];
  strcpy(path, argv[0]);
  char *p = strrchr(path, '/');
  char self_name[len - ((p) ? p - path + 1: 0) + 1];
  strcpy(self_name, (p) ? p + 1: path);

  if(strcmp(self_name, "uninstall.tns") == 0) {
    if (show_msgbox_2b(title, confirmUninst, yes, no) == 2)
      return 0;
    if(remove(config_path) == 0)
      show_msgbox(title, successUninst);
    else
      show_msgbox(title, errorUninst);
    return 0;
  }

  if (is_cx) lcd_incolor();

  zlock(config_path);
  
  wait_no_key_pressed();

  return 0;
}