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

/* Wrapper provided by build system for static function under test */
extern void test_findConstraintFunc(sqlite3_context *ctx, int NotUsed, sqlite3_value **argv);

/* UDF that forwards to the function under test so we can get a valid sqlite3_context */
static void udf_findc(sqlite3_context *ctx, int argc, sqlite3_value **argv){
  /* Forward directly to the function under test. The function only uses the first two args. */
  (void)argc; /* Silence unused warning since function ignores argc */
  test_findConstraintFunc(ctx, 0, argv);
}

static void register_findc(sqlite3 *db){
  int rc = sqlite3_create_function(db, "findc", 2, SQLITE_UTF8, 0, udf_findc, 0, 0);
  TEST_ASSERT_EQUAL_INT_MESSAGE(SQLITE_OK, rc, "sqlite3_create_function(findc) failed");
}

static void assert_findc_result(sqlite3 *db,
                                const char *sqlDef,   /* CREATE TABLE SQL or other */
                                const char *consName, /* constraint name, may be NULL */
                                int expectType,       /* SQLITE_INTEGER or SQLITE_NULL */
                                int expectInt){       /* expected int if expectType==SQLITE_INTEGER */
  sqlite3_stmt *stmt = 0;
  int rc = sqlite3_prepare_v2(db, "SELECT findc(?,?)", -1, &stmt, 0);
  TEST_ASSERT_EQUAL_INT_MESSAGE(SQLITE_OK, rc, "prepare SELECT findc failed");
  if( sqlDef ){
    rc = sqlite3_bind_text(stmt, 1, sqlDef, -1, SQLITE_TRANSIENT);
  }else{
    rc = sqlite3_bind_null(stmt, 1);
  }
  TEST_ASSERT_EQUAL_INT_MESSAGE(SQLITE_OK, rc, "bind #1 failed");

  if( consName ){
    rc = sqlite3_bind_text(stmt, 2, consName, -1, SQLITE_TRANSIENT);
  }else{
    rc = sqlite3_bind_null(stmt, 2);
  }
  TEST_ASSERT_EQUAL_INT_MESSAGE(SQLITE_OK, rc, "bind #2 failed");

  rc = sqlite3_step(stmt);
  TEST_ASSERT_EQUAL_INT_MESSAGE(SQLITE_ROW, rc, "step did not return row");
  int gotType = sqlite3_column_type(stmt, 0);
  TEST_ASSERT_EQUAL_INT(expectType, gotType);
  if( expectType==SQLITE_INTEGER ){
    int got = sqlite3_column_int(stmt, 0);
    TEST_ASSERT_EQUAL_INT(expectInt, got);
  }

  rc = sqlite3_step(stmt);
  TEST_ASSERT_EQUAL_INT_MESSAGE(SQLITE_DONE, rc, "expected single row");

  rc = sqlite3_finalize(stmt);
  TEST_ASSERT_EQUAL_INT_MESSAGE(SQLITE_OK, rc, "finalize failed");
}

/* Unity hooks */
void setUp(void) {
  /* No-op */
}
void tearDown(void) {
  /* No-op */
}

/* Tests */

static void test_findConstraintFunc_basic_match(void){
  sqlite3 *db = 0;
  TEST_ASSERT_EQUAL_INT(SQLITE_OK, sqlite3_open(":memory:", &db));
  register_findc(db);

  const char *sql =
    "CREATE TABLE t ("
    "  a INT,"
    "  CONSTRAINT c1 CHECK(a > 0),"
    "  b TEXT"
    ");";

  /* Exact name */
  assert_findc_result(db, sql, "c1", SQLITE_INTEGER, 1);
  /* Not present */
  assert_findc_result(db, sql, "c2", SQLITE_INTEGER, 0);

  sqlite3_close(db);
}

static void test_findConstraintFunc_case_insensitive_and_quoted(void){
  sqlite3 *db = 0;
  TEST_ASSERT_EQUAL_INT(SQLITE_OK, sqlite3_open(":memory:", &db));
  register_findc(db);

  /* Quoted identifier with spaces; test case-insensitive compare */
  const char *sql =
    "CREATE TABLE t ("
    "  a INT,"
    "  CONSTRAINT \"My Constr\" UNIQUE(a)"
    ");";

  assert_findc_result(db, sql, "My Constr", SQLITE_INTEGER, 1);
  assert_findc_result(db, sql, "my constr", SQLITE_INTEGER, 1);
  assert_findc_result(db, sql, "MY CONSTR", SQLITE_INTEGER, 1);
  assert_findc_result(db, sql, "Other", SQLITE_INTEGER, 0);

  sqlite3_close(db);
}

static void test_findConstraintFunc_bracket_and_backtick_quoted(void){
  sqlite3 *db = 0;
  TEST_ASSERT_EQUAL_INT(SQLITE_OK, sqlite3_open(":memory:", &db));
  register_findc(db);

  const char *sql1 =
    "CREATE TABLE t1 ("
    "  a INT,"
    "  CONSTRAINT [C-Name] CHECK(a IS NOT NULL)"
    ");";
  assert_findc_result(db, sql1, "c-name", SQLITE_INTEGER, 1);
  assert_findc_result(db, sql1, "C-Name", SQLITE_INTEGER, 1);
  assert_findc_result(db, sql1, "other", SQLITE_INTEGER, 0);

  const char *sql2 =
    "CREATE TABLE t2 ("
    "  a INT,"
    "  CONSTRAINT `bk` CHECK(a > 0)"
    ");";
  assert_findc_result(db, sql2, "bk", SQLITE_INTEGER, 1);
  assert_findc_result(db, sql2, "BK", SQLITE_INTEGER, 1);
  assert_findc_result(db, sql2, "xx", SQLITE_INTEGER, 0);

  sqlite3_close(db);
}

static void test_findConstraintFunc_with_comments_and_nested_parens(void){
  sqlite3 *db = 0;
  TEST_ASSERT_EQUAL_INT(SQLITE_OK, sqlite3_open(":memory:", &db));
  register_findc(db);

  const char *sql =
    "/* heading comment */ CREATE   /* mid */  TABLE t (\n"
    "  a INT, -- column a\n"
    "  CONSTRAINT /*name*/ \"C 1\" CHECK( (a > 0) AND (a < 10) )\n"
    "); -- trailer\n";

  assert_findc_result(db, sql, "C 1", SQLITE_INTEGER, 1);
  assert_findc_result(db, sql, "c 1", SQLITE_INTEGER, 1);
  assert_findc_result(db, sql, "not-there", SQLITE_INTEGER, 0);

  sqlite3_close(db);
}

static void test_findConstraintFunc_no_named_constraints_returns_0(void){
  sqlite3 *db = 0;
  TEST_ASSERT_EQUAL_INT(SQLITE_OK, sqlite3_open(":memory:", &db));
  register_findc(db);

  /* Constraints without explicit "CONSTRAINT <name>" should not match any name */
  const char *sql =
    "CREATE TABLE t ("
    "  a INT,"
    "  UNIQUE(a),"
    "  PRIMARY KEY(a)"
    ");";

  assert_findc_result(db, sql, "anything", SQLITE_INTEGER, 0);

  sqlite3_close(db);
}

static void test_findConstraintFunc_no_left_paren_in_sql_returns_0(void){
  sqlite3 *db = 0;
  TEST_ASSERT_EQUAL_INT(SQLITE_OK, sqlite3_open(":memory:", &db));
  register_findc(db);

  /* Not a CREATE TABLE statement, and no '(' token before TK_ILLEGAL */
  const char *sql = "DROP TABLE t;";
  assert_findc_result(db, sql, "c1", SQLITE_INTEGER, 0);

  sqlite3_close(db);
}

static void test_findConstraintFunc_null_arguments_return_null(void){
  sqlite3 *db = 0;
  TEST_ASSERT_EQUAL_INT(SQLITE_OK, sqlite3_open(":memory:", &db));
  register_findc(db);

  /* NULL SQL input */
  assert_findc_result(db, NULL, "c1", SQLITE_NULL, 0);

  /* NULL constraint name input */
  const char *sql =
    "CREATE TABLE t ( a INT, CONSTRAINT c1 CHECK(a>0) );";
  assert_findc_result(db, sql, NULL, SQLITE_NULL, 0);

  /* Both NULL */
  assert_findc_result(db, NULL, NULL, SQLITE_NULL, 0);

  sqlite3_close(db);
}

static void test_findConstraintFunc_multiple_constraints_both_detected(void){
  sqlite3 *db = 0;
  TEST_ASSERT_EQUAL_INT(SQLITE_OK, sqlite3_open(":memory:", &db));
  register_findc(db);

  const char *sql =
    "CREATE TABLE t ("
    "  a INT, b INT,"
    "  CONSTRAINT cA CHECK(a>0),"
    "  CONSTRAINT cB UNIQUE(b)"
    ");";

  assert_findc_result(db, sql, "cA", SQLITE_INTEGER, 1);
  assert_findc_result(db, sql, "ca", SQLITE_INTEGER, 1); /* case-insensitive */
  assert_findc_result(db, sql, "cB", SQLITE_INTEGER, 1);
  assert_findc_result(db, sql, "cb", SQLITE_INTEGER, 1);
  assert_findc_result(db, sql, "nope", SQLITE_INTEGER, 0);

  sqlite3_close(db);
}

int main(void){
  UNITY_BEGIN();
  RUN_TEST(test_findConstraintFunc_basic_match);
  RUN_TEST(test_findConstraintFunc_case_insensitive_and_quoted);
  RUN_TEST(test_findConstraintFunc_bracket_and_backtick_quoted);
  RUN_TEST(test_findConstraintFunc_with_comments_and_nested_parens);
  RUN_TEST(test_findConstraintFunc_no_named_constraints_returns_0);
  RUN_TEST(test_findConstraintFunc_no_left_paren_in_sql_returns_0);
  RUN_TEST(test_findConstraintFunc_null_arguments_return_null);
  RUN_TEST(test_findConstraintFunc_multiple_constraints_both_detected);
  return UNITY_END();
}