#include "sqliteInt.h"
#include "unity.h"
#include <string.h>
#include <stdlib.h>
#include <stdio.h>

/* Wrapper for the static function under test (provided by the build as per instructions) */
extern int test_getConstraintToken(const u8 *z, int *piToken);

void setUp(void) {
  /* No global setup required */
}

void tearDown(void) {
  /* No global teardown required */
}

/* Helper: return index of first occurrence of character c in s, or -1 if not found */
static int idx_of_char(const char *s, char c){
  const char *p = strchr(s, c);
  if( !p ) return -1;
  return (int)(p - s);
}

/* Helper: return index immediately after the first occurrence of substring sub in s, or -1 if not found */
static int idx_after_sub(const char *s, const char *sub){
  const char *p = strstr(s, sub);
  if( !p ) return -1;
  return (int)((p - s) + (int)strlen(sub));
}

/* 1) Simple identifier with no leading whitespace/comments */
void test_getConstraintToken_simple_identifier(void) {
  const char *z = "abc def";
  int t = 0;
  int n = test_getConstraintToken((const u8*)z, &t);
  TEST_ASSERT_EQUAL_INT(TK_ID, t);
  TEST_ASSERT_EQUAL_INT(3, n); /* "abc" length */
}

/* 2) Skips leading spaces and comments, then identifies "abc" */
void test_getConstraintToken_skips_space_and_comments_before_id(void) {
  const char *z = "   /* comment */\n-- line comment\nabc def";
  int expected = idx_after_sub(z, "abc"); /* position immediately after "abc" */
  TEST_ASSERT_TRUE_MESSAGE(expected > 0, "Did not find 'abc' in test string");

  int t = 0;
  int n = test_getConstraintToken((const u8*)z, &t);

  TEST_ASSERT_EQUAL_INT(TK_ID, t);
  TEST_ASSERT_EQUAL_INT(expected, n);
}

/* 3) Minimal parenthesis token "()" followed by sentinel 'X' */
void test_getConstraintToken_minimal_parentheses(void) {
  const char *z = "()X";
  int expected = idx_of_char(z, 'X');
  TEST_ASSERT_TRUE_MESSAGE(expected >= 0, "Sentinel 'X' not found");

  int t = 0;
  int n = test_getConstraintToken((const u8*)z, &t);

  TEST_ASSERT_EQUAL_INT(TK_LP, t);
  TEST_ASSERT_EQUAL_INT(expected, n);
}

/* 4) Parenthesis token with inner tokens and leading spaces; should consume up to the matching ')' */
void test_getConstraintToken_parentheses_with_inner_tokens(void) {
  const char *z = "   (two three)X";
  int expected = idx_of_char(z, 'X');
  TEST_ASSERT_TRUE_MESSAGE(expected >= 0, "Sentinel 'X' not found");

  int t = 0;
  int n = test_getConstraintToken((const u8*)z, &t);

  TEST_ASSERT_EQUAL_INT(TK_LP, t);
  TEST_ASSERT_EQUAL_INT(expected, n);
}

/* 5) Nested parentheses: (a(b)c)X -> should consume exactly up to the ')' before X */
void test_getConstraintToken_nested_parentheses(void) {
  const char *z = "(a(b)c)X";
  int expected = idx_of_char(z, 'X');
  TEST_ASSERT_TRUE_MESSAGE(expected >= 0, "Sentinel 'X' not found");

  int t = 0;
  int n = test_getConstraintToken((const u8*)z, &t);

  TEST_ASSERT_EQUAL_INT(TK_LP, t);
  TEST_ASSERT_EQUAL_INT(expected, n);
}

/* 6) Unclosed parenthesis at end-of-input: expect TK_ILLEGAL and only the '(' consumed */
void test_getConstraintToken_unclosed_parenthesis_hits_illegal(void) {
  const char *z = "(abc";
  int t = 0;
  int n = test_getConstraintToken((const u8*)z, &t);

  TEST_ASSERT_EQUAL_INT(TK_ILLEGAL, t);
  /* Expect at least the leading '(' to be consumed; tokenizer should return 0-length illegal at EOF */
  TEST_ASSERT_EQUAL_INT(1, n);
}

/* 7) Unterminated string literal inside parentheses should trigger TK_ILLEGAL */
void test_getConstraintToken_unterminated_string_inside_parentheses(void) {
  const char *z = "('unterminated";
  int t = 0;
  int n = test_getConstraintToken((const u8*)z, &t);

  TEST_ASSERT_EQUAL_INT(TK_ILLEGAL, t);
  /* Should have consumed the '(' plus at least part of the string token */
  TEST_ASSERT_TRUE(n > 1);
  TEST_ASSERT_TRUE(n <= (int)strlen(z));
}

/* 8) Non-parenthesis keyword token (SELECT) */
void test_getConstraintToken_keyword_token(void) {
  const char *z = "SELECT rest";
  int t = 0;
  int n = test_getConstraintToken((const u8*)z, &t);

  TEST_ASSERT_EQUAL_INT(TK_SELECT, t);
  TEST_ASSERT_EQUAL_INT(6, n); /* "SELECT" length */
}

int main(void) {
  UNITY_BEGIN();

  RUN_TEST(test_getConstraintToken_simple_identifier);
  RUN_TEST(test_getConstraintToken_skips_space_and_comments_before_id);
  RUN_TEST(test_getConstraintToken_minimal_parentheses);
  RUN_TEST(test_getConstraintToken_parentheses_with_inner_tokens);
  RUN_TEST(test_getConstraintToken_nested_parentheses);
  RUN_TEST(test_getConstraintToken_unclosed_parenthesis_hits_illegal);
  RUN_TEST(test_getConstraintToken_unterminated_string_inside_parentheses);
  RUN_TEST(test_getConstraintToken_keyword_token);

  return UNITY_END();
}