#include <stdint.h>
#include <LiquidCrystal.h>
#include "src/list/src/list.h"

LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

//#define REFRESH 1
#define DEBUG

uint8_t up_arrow[8]   = {0x04,0x0E,0x1F,0x1F,0x00,0x00,0x00,0x00};
uint8_t down_arrow[8] = {0x00,0x00,0x00,0x1F,0x1F,0x0E,0x04,0x04};

typedef struct InfoState {
  char* info;
  int len;
  int fullLines;
  int Nlines;
  int lastlinelen;
  char *pos1, *pos2, *pos3;
  list_t *wrap;
  list_iterator_t *it;
} InfoState;

void setup() {
  Serial.begin(9600);
  lcd.begin(16, 2);
  lcd.createChar(0, up_arrow);
  lcd.createChar(1, down_arrow);
  lcd.setCursor(0, 0);
  lcd.print("...............");
  lcd.setCursor(0, 1);
  lcd.print("...............");
}

void loop() {
  char* cinfo = "Far far away, a\n\nbehind the word mountains, far from the countries Vokalia and Consonantia, there live the blind texts.";
  //String info = "hello,`world!wwwwwwwwwwwwwwww";
  InfoState st;
  initInfoScreen(&st, cinfo);
  
#ifdef DEBUG
  Serial.println(String("len: ") + st.len);
#endif

#ifdef DEBUG
  Serial.println("down");
#endif
  for (int i = 0; i < 3; ++i) {
    delay(1000);
    scrollDown(&st);
  }
  
#ifdef DEBUG
  Serial.println("up");
#endif
  for (int i = 0; i < 5; ++i) {
    delay(1000);
    scrollUp(&st);
  }
  
#ifdef DEBUG
  Serial.println("down2");
#endif
  for (int i = 0; i < 3; ++i) {
    delay(1000);
    scrollDown(&st);
  }
  
#ifdef DEBUG
  Serial.println("up2");
#endif
  for (int i = 0; i < 5; ++i) {
    delay(1000);
    scrollUp(&st);
  }

  delay(3000);
}

list_t* aux_gen_wrap_list(list_t* wrap, char* text) {
  if (wrap == NULL) {
    wrap = list_new();
  }
  char* curr = text;
  int suf = 0;
  list_node_t *node;
  if (list_rpush(wrap, list_node_new(0)) == NULL) {
    return NULL;
  }
  while (*curr != '\0') {
    //printf("suf: %d\tpos: %d\n", suf, (unsigned int)(curr-text));
    if (suf < 15) {
      if (*curr != '\n' && *curr != '\r') {
        ++suf;
      } else {
        if (list_rpush(wrap, list_node_new((unsigned int)(curr-text))) == NULL) {
          return NULL;
        }
        suf = 0;
      }
    } else {
      if (list_rpush(wrap, list_node_new((unsigned int)(curr-text))) == NULL) {
        return NULL;
      }
      suf = (*curr != '\n' && *curr != '\r') ? 1 : 0;      
    }
    ++curr;
  }
  if (list_rpush(wrap, list_node_new(strlen(text))) == NULL) {
    return NULL;
  }
  return wrap;
}

void initInfoState(InfoState* st, char* text) {
  st->info = text;
  st->len = strlen(text);
  st->fullLines = st->len / 15;
  st->Nlines = (st->len + 14) / 15;
  st->lastlinelen = st->len % 15;
  st->pos1 = text;
  st->pos2 = text;
  st->pos3 = text;
  st->wrap = list_new();
  st->wrap = aux_gen_wrap_list(st->wrap, st->info);
  st->it = list_iterator_new(st->wrap, LIST_HEAD);
}

void initInfoScreen(InfoState* st, char* text) {
  initInfoState(st, text);
  lcd.setCursor(0, 0);
  
  /*
  if (*(st->pos1) == '\n' || *(st->pos1) == '\r') {
    lcd_blank_line();
    ++st->pos1;
    ++st->pos2;
  } else {
    st->pos2 += lcd_print_line(st->pos1);
  }
  lcd.setCursor(0, 1);
  if ((*(st->pos2) == '\n' || *(st->pos2) == '\r') && *(st->pos2 - 1) == *(st->pos2)) {
    lcd_blank_line();
  } else {
    lcd_print_line(st->pos2);
  }
#ifdef DEBUG
  //Serial.println(String("pos1: ") + st->pos1);
  //Serial.println(String("pos2: ") + st->pos2);
  Serial.println("init");
  Serial.print(st->pos1-st->info);
  Serial.println(String(" ")+(st->pos2-st->info));
#endif
  */
}


void scrollDown(InfoState* st) {
  st->pos1 = st->pos2;
  lcd.setCursor(0, 0);
  if ((*(st->pos1) == '\n' || *(st->pos1) == '\r') && *(st->pos1 - 1) == *(st->pos1)) {
    lcd_blank_line();
    ++st->pos1;
    ++st->pos2;
  } else {
    st->pos2 += lcd_print_line(st->pos1);
  }
  lcd.setCursor(0, 1);
  if ((*(st->pos2) == '\n' || *(st->pos2) == '\r') && *(st->pos2 - 1) == *(st->pos2)) {
    lcd_blank_line();
  } else {
    lcd_print_line(st->pos2);
  }
#ifdef DEBUG
  //Serial.println(String("pos1: ") + st->pos1);
  //Serial.println(String("pos2: ") + st->pos2);
  Serial.print(st->pos1-st->info);
  Serial.println(String(" ")+(st->pos2-st->info));
#endif
}

void scrollUp(InfoState* st) {
  if (st->pos1 > st->info) {
    st->pos2 = st->pos1;
    int i = 1;
    int va = 1;
    /*
    int bound = min(st->pos1, 15);
    Serial.println(String("bound: ")+bound);
    while (i < bound) {
      if (st->info[st->pos1-i] != '\n' && st->info[st->pos1-i] != '\r') {
        ++i;
      } else 
      if (i == 1){ ++i; ++bound; } else 
      {
        break;
      }
    }
    */
    
    /*
    while (i < st->pos1-st->info && va < 15) {
      if (st->info[st->pos1-i] != '\n' && st->info[st->pos1-i] != '\r') {
        ++i;
        ++va;
      } else 
      if (i == 1){ ++i; } else 
      {
        break;
      }
    }
    
    st->pos1 -= i;
    */
    bool is_blank = false;
    while (st->pos1 > st->info && va <= 15) {
      if (*(st->pos1) != '\n' && *(st->pos1) != '\r') {
        ++i;
        ++va;
      } else if (*(st->pos1 - 1) == *(st->pos1)) {
        is_blank = true;
        --st->pos1;
        break;
      }
      --st->pos1;
    }
    while (st->pos1 > st->info && (*(st->pos1) == '\n' || *(st->pos1) == '\r')) {
      --st->pos1;
    }
    //st->pos1 -= i;
    
    lcd.setCursor(0, 0);
    if (is_blank) {
      lcd_blank_line();
    } else {
      lcd_print_line(st->pos1);
    }
    lcd.setCursor(0, 1);
    if ((*(st->pos2) == '\n' || *(st->pos2) == '\r') && *(st->pos2 - 1) == *(st->pos2)) {
      lcd_blank_line();
    } else {
      lcd_print_line(st->pos2);
    }
  }
#ifdef DEBUG
  //Serial.println(String("pos1: ") + st->pos1);
  //Serial.println(String("pos2: ") + st->pos2);
  Serial.print(st->pos1-st->info);
  Serial.println(String(" ")+(st->pos2-st->info));
#endif
}

int lcd_print_line(char* str) {
  int i = 0;
  int va = 0;
  /*
  int bound = min(strlen(str), 15);
  while (i < bound) {
    if (str[i] != '\n' && str[i] != '\r') {
      lcd.print(str[i++]);
    } else 
    if (i == 0){ ++i; ++bound;} else 
    {
      break;
    }
  }
  */
  int slen = strlen(str);
  while (i < slen && va < 15) {
    if (str[i] != '\n' && str[i] != '\r') {
      lcd.print(str[i++]);
      ++va;
    } else 
    if (i == 0){ ++i; } else 
    {
      break;
    }
  }
  
  if (va < 15) {
#if !REFRESH
    for (int j = 15 - va; j > 0; --j) {
      lcd.print(' ');
    }
#endif
    ++i;
  }
  return i;
}

/*
  Separate a substring that can be printed on one line, and return the 
  original string position corresponding to the end of the substring.
 */
/*
char* aux_sub_line(char* str, char substr[16]) {
  int suf = 0;
  char* curr = str;
  memset(substr, 0, 16);
  
  while (*curr != '\0' && suf < 15) {
    if (*curr != '\n' && *curr != '\r') {
      substr[suf++] = *(curr++);
    } else 
    if (curr == str){ ++curr; } else 
    {
      break;
    }
  }
  
#if !REFRESH
  while (suf < 15) {
    substr[suf++] = ' ';
  }
#endif
  return curr;
}

char* aux_sub_line_rev(char* str, char substr[16]) {
  int suf = 0;
  char* curr = str;
  memset(substr, 0, 16);
  
  while (*curr != '\0' && suf < 15) {
    if (*curr != '\n' && *curr != '\r') {
      substr[suf++] = *(curr--);
    } else 
    if (curr == str){ --curr; } else 
    {
      break;
    }
  }
  
  
}
*/
void lcd_blank_line() {
  for (int i = 0; i < 15; ++i) {
    lcd.print(' ');
  }
}