#include "reader.h"
#include <string.h>

typedef enum {
  TOKEN_ZERO,
  TOKEN_LITERAL,
  TOKEN_PIPE,
  TOKEN_OR,
  TOKEN_AND,
  TOKEN_LINE_COMMENT,
  TOKEN_O_BRACKET,
  TOKEN_C_BRACKET,
  TOKEN_O_BRACES,
  TOKEN_C_BRACES,
  TOKEN_O_PARENTHESIS,
  TOKEN_C_PARENTHESIS,
  TOKEN_MULTIPLICATION,
  TOKEN_PLUS,
  TOKEN_MINUS,
  TOKEN_DIVISION
} TokenType;

typedef struct {
  TokenType type;
  String value;
} Token;

typedef struct {
  Arena *arena;
  u32 size;
  Token *list;
} TokenList;

TokenList token_list_new(Arena *arena, u64 capacity) {
  TokenList list;
  list.arena = arena;
  list.size = 0;
  list.list = arena_array(arena, Token, capacity);

  return list;
}

int token_compare_symbol(String *slice, Token *token) {
  if (string_compare_literal(slice, "|>") == 0) {
    token->type = TOKEN_PIPE;
    memcpy(&(token->value), slice, 2);
    return 1;
  } else if (string_compare_literal(slice, "||") == 0) {
    token->type = TOKEN_OR;
    memcpy(&(token->value), slice, 2);
    return 1;
  } else if (string_compare_literal(slice, "&&") == 0) {
    token->type = TOKEN_AND;
    memcpy(&(token->value), slice, 2);
    return 1;
  } else if (string_compare_literal(slice, "//") == 0) {
    token->type = TOKEN_LINE_COMMENT;
    memcpy(&(token->value), slice, 2);
    return 1;
  }

  if (string_compare_literal(slice, "}") == 0) {
    token->type = TOKEN_O_BRACES;
    memcpy(&(token->value), slice, 1);
    return 1;
  } else if (string_compare_literal(slice, "{") == 0) {
    token->type = TOKEN_C_BRACES;
    memcpy(&(token->value), slice, 1);
    return 1;
  } else if (string_compare_literal(slice, "[") == 0) {
    token->type = TOKEN_O_BRACKET;
    memcpy(&(token->value), slice, 1);
    return 1;
  } else if (string_compare_literal(slice, "]") == 0) {
    token->type = TOKEN_C_BRACKET;
    memcpy(&(token->value), slice, 1);
    return 1;
  } else if (string_compare_literal(slice, "(") == 0) {
    token->type = TOKEN_O_PARENTHESIS;
    memcpy(&(token->value), slice, 1);
    return 1;
  } else if (string_compare_literal(slice, ")") == 0) {
    token->type = TOKEN_C_PARENTHESIS;
    memcpy(&(token->value), slice, 1);
    return 1;
  } else if (string_compare_literal(slice, "*") == 0) {
    token->type = TOKEN_MULTIPLICATION;
    memcpy(&(token->value), slice, 1);
    return 1;
  } else if (string_compare_literal(slice, "+") == 0) {
    token->type = TOKEN_PLUS;
    memcpy(&(token->value), slice, 1);
    return 1;
  } else if (string_compare_literal(slice, "-") == 0) {
    token->type = TOKEN_MINUS;
    memcpy(&(token->value), slice, 1);
    return 1;
  } else if (string_compare_literal(slice, "/") == 0) {
    token->type = TOKEN_DIVISION;
    memcpy(&(token->value), slice, 1);
    return 1;
  }

  return 0;
}

int tokenize(String slice, Token *token) {
  if (slice.size < 3 && token_compare_symbol(&slice, token) == 1) {
    return 1;
  }

  return 0;
}

TokenList tokennize_list(Arena *arena, Reader *reader) {
  u32 start = 0, end = 1, count = 0;
  String slice;
  Token token;
  TokenList list;

  memset(&token, 0, sizeof(token));

  /* Count tokens */
  do {
    slice.size = end - start;
    slice.buf = &(reader->buffer[start]);

    if (tokenize(slice, &token)) {
      count++;
      end = start;
    }

    end++;
  } while (reader_advance(reader, &start, &end));

  reader_reset(reader);
  list = token_list_new(arena, count);
  count = 0;

  /* Process tokens */
  do {
    slice.size = end - start;
    slice.buf = &(reader->buffer[start]);

    if (tokenize(slice, &token)) {
      memcpy(&(list.list[count++]), &token, sizeof(token));
    }

    end++;
  } while (reader_advance(reader, &start, &end));

  return list;
}