#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <string.h>

#include "slr.h"

void print_token(Token token){
  printf("Token Value: ");
  for(int i = 0; token.value[i] != '\0'; i++){
    printf("%c", token.value[i]);
  }
  printf("\nToken Type: ");
  if(token.type == INT){
    printf("int\n");
  }
  if(token.type == KEYWORD){
    printf("Keyword\n");
  }
  if(token.type == SEPARATOR){
    printf("Separator\n");
  }
}

Token *generate_number(char *current, int *current_index)
{
    Token *token = malloc(sizeof(Token));
    token->type = INT;
    char *value = malloc(8 * sizeof(char));
    int value_index = 0;
    while(isdigit(current[*current_index]) && current[*current_index] != '\0'){
        value[value_index] = current[*current_index];
        value_index++;
        (*current_index)++;
    }
    value[value_index] = '\0';
    token->value = value;
    return token;
}

Token *generate_keyword(char *current, int *current_index)
{
    Token *token = malloc(sizeof(Token));
    char *keyword = malloc(8 * sizeof(char));
    int keyword_index = 0;
    while(isalpha(current[*current_index]) && current[*current_index] != '\0'){
        keyword[keyword_index] = current[*current_index];
        keyword_index++;
        (*current_index)++;
    }
    keyword[keyword_index] = '\0';
    if(strcmp(keyword, "exit") == 0){
        printf("TYPE EXIT\n");
        token->type = KEYWORD;
    }
    token->type = KEYWORD;
    token->value = keyword;
    return token;
}

Token *lexer(char *buf){
    char *current = strdup(buf);
    int current_index = 0, tokens_index = 0;

    Token *tokens = malloc(sizeof(Token) * 1024);
    while(current[current_index] != '\0'){
        Token *token = NULL;
        if(current[current_index] == ';'){
            token = malloc(sizeof(Token));
            char *value = malloc(2 * sizeof(char));
            value[0] = current[current_index];
            value[1] = '\0';
            token->value = value;
            token->type = SEPARATOR;
            tokens[tokens_index] = *token;
            tokens_index++;
            printf("FOUND SEMICOLON\n");
        } else if(current[current_index] == '('){
            token = malloc(sizeof(Token));
            char *value = malloc(2 * sizeof(char));
            value[0] = current[current_index];
            value[1] = '\0';
            token->value = value;
            token->type = SEPARATOR;
            tokens[tokens_index] = *token;
            tokens_index++;
            printf("FOUND OPEN PAREN\n");
        } else if(current[current_index] == ')'){
            token = malloc(sizeof(Token));
            char *value = malloc(2 * sizeof(char));
            value[0] = current[current_index];
            value[1] = '\0';
            token->value = value;
            token->type = SEPARATOR;
            tokens[tokens_index] = *token;
            tokens_index++;
            printf("FOUND CLOSE PAREN\n");
        } else if(isdigit(current[current_index])){
            token = generate_number(current, &current_index); 
            tokens[tokens_index] = *token;
            tokens_index++;
            current_index--;
        } else if(isalpha(current[current_index])){
            token = generate_keyword(current, &current_index);
            tokens[tokens_index] = *token;
            tokens_index++;
            current_index--;
        }
        if (token != NULL) {
            print_token(*token);
        }
        current_index++;
    }
    tokens[tokens_index].type = END_OF_TOKENS;
    tokens[tokens_index].value = '\0';
    return tokens;
}

long long get_file_length(FILE *file)
{
    fseeko(file, 0, SEEK_END);
    long long length = ftello(file);
    fseeko(file, 0, SEEK_SET);
    return length;
}


int main(int argc, char **argv)
{
    if (argc < 2) {
        fprintf(stderr, "\033[1;37mslr:\033[0m \033[1;31mfatal error:\033[0m no input files\ninterpretation termined.\n");
        exit(1);
    }
    FILE *file = fopen(argv[1], "r");
    long long length = get_file_length(file);
    char *buf = malloc(length * sizeof(char));
    fread(buf, 1, length, file);
    fclose(file);
    buf[length + 1] = '\0';
    Token *tokens = lexer(buf);
}