#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 enum InfoRet {
  IR_UNKNOWN = -1,
  IR_NORMAL = 0,
  IR_UNSUCCESS
} InfoRet;

typedef struct InfoState {
  char* info;
  list_node_t *pos1, *pos2, *pos3;
  list_t *wrap;
} InfoState;

void lcd_blank_line() {
  for (int i = 0; i < 15; ++i) {
    lcd.print(' ');
    //putchar(' ');
  }
}

int lcd_print_between(char* str, int pos1, int pos2) {
  //int i = 0;
  int va = 0;
  
  char* p = str+pos1;
  //int slen = strlen(str);
  while (p < str+pos2) {
    if (*p != '\n' && *p != '\r') {
      lcd.print(*p);
      //putchar(*p);
      ++va;
    } //else 
    //if (i == 0){ ++i; } else 
    //{
    //  break;
    //}
    ++p;
  }
  
  if (va < 15) {
    for (int j = 15 - va; j > 0; --j) {
      lcd.print(' ');
      //putchar(' ');
    }
  }
  //putchar('!');
  return va;
}

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(-1)) == 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((int)(curr-text))) == NULL) {
    return NULL;
  }
  return wrap;
}

void initInfoState(InfoState* st, char* text) {
  st->info = text;
  st->wrap = list_new();
  st->wrap = aux_gen_wrap_list(st->wrap, st->info);
  st->pos1 = list_at(st->wrap, 0);
  st->pos2 = st->pos3 = NULL;
}

InfoRet initInfoScreen(InfoState* st, char* text) {
  initInfoState(st, text);
  //printf("%d\n", st->wrap->len);
  if (st->pos1 == NULL) {
    return IR_UNKNOWN;
  }
  lcd.setCursor(0, 0);
  if ((st->pos2 = st->pos1->next)) {
    //printf("hello\n");
    //printf("%d\n", st->pos2->val);
    int tmp = lcd_print_between(st->info, 0, (int)st->pos2->val);
    //printf("%d\n", tmp);
    //printf("%d\n", st->wrap->len);
    if ((st->pos3 = st->pos2->next)) {
      //printf("\n");
      lcd.setCursor(0, 1);
      //printf("%d\n", st->pos2->val);
      //printf("%d\n", st->pos3->val);
      int tmp = lcd_print_between(st->info, (int)st->pos2->val, (int)st->pos3->val);
      //printf("%d\n", tmp);
      //printf("%d\n", st->wrap->len);
    } else {
      //printf("\n");
      lcd.setCursor(0, 1);
      lcd_blank_line();
    }
  } else {
    return IR_UNKNOWN;
  }
  return IR_NORMAL;
}

InfoRet scrollDown(InfoState* st) {
  if (st->pos2) {
    st->pos1 = st->pos2;
  } else {
    return IR_UNKNOWN;
  }
  if (st->pos3) {
    st->pos2 = st->pos3;
  } else {
    return IR_UNSUCCESS;
  }
  lcd.setCursor(0, 0);
  int tmp = lcd_print_between(st->info, (int)st->pos1->val, (int)st->pos2->val);
  if ((st->pos3 = st->pos3->next)) {
    //printf("\n");
    lcd.setCursor(0, 1);
    int tmp = lcd_print_between(st->info, (int)st->pos2->val, (int)st->pos3->val);
  } else {
    //printf("\n");
    lcd.setCursor(0, 1);
    lcd_blank_line();
  }
  return IR_NORMAL;
}

InfoRet scrollUp(InfoState* st) {
  if (st->pos2) {
    st->pos3 = st->pos2;
  } else {
    return IR_UNKNOWN;
  }
  
  if (st->pos1 == NULL) {
    return IR_UNKNOWN;
  } else if ((int)st->pos1->val == -1) {
    return IR_UNSUCCESS;
  } else {
    st->pos2 = st->pos1;
  }
  
  if ((st->pos1 = st->pos1->prev)) {
    lcd.setCursor(0, 0);
    if (st->pos1->val == -1) {
      int tmp = lcd_print_between(st->info, 0, (int)st->pos2->val);
    } else {
      int tmp = lcd_print_between(st->info, (int)st->pos1->val, (int)st->pos2->val);
    }
  } else {
    return IR_UNKNOWN;
  }
  //printf("\n");
  lcd.setCursor(0, 1);
  int tmp = lcd_print_between(st->info, (int)st->pos2->val, (int)st->pos3->val);
  return IR_NORMAL;
}

void destoryInfoState(InfoState* st) {
  st->pos1 = st->pos2 = st->pos3 = NULL;
  list_destroy(st->wrap);
  st->info = NULL;
}

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);
  for (int i = 0; i < 10; ++i) {
    delay(1000);
    scrollDown(&st);
  }
  for (int i = 0; i < 10; ++i) {
    delay(1000);
    scrollUp(&st);
  }
/*
#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);
}

/*
int lcd_print_line(char* str) {
  int i = 0;
  int va = 0;
  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;
}
*/