#include "sqliteInt.h"
#include "unity.h"

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

/* The wrapper added for testing static function renameColumnIdlistNames */
extern void test_renameColumnIdlistNames(
  Parse *pParse,
  RenameCtx *pCtx,
  const IdList *pIdList,
  const char *zOld
);

/* Globals for a simple db/parse lifecycle per test */
static sqlite3 *gDb = NULL;
static Parse gParse;

/* Helper: build an IdList by appending names using SQLite's own allocator */
static IdList *makeIdList(Parse *pParse, const char **azName, int nName){
  IdList *pList = 0;
  for(int i = 0; i < nName; i++){
    Token t;
    t.z = azName[i];
    t.n = (int)strlen(azName[i]);
    pList = sqlite3IdListAppend(pParse, pList, &t);
    TEST_ASSERT_NOT_NULL_MESSAGE(pList, "sqlite3IdListAppend returned NULL");
  }
  return pList;
}

/* Unity setup/teardown */
void setUp(void) {
  int rc = sqlite3_open(":memory:", &gDb);
  TEST_ASSERT_EQUAL_INT_MESSAGE(SQLITE_OK, rc, "sqlite3_open failed");
  memset(&gParse, 0, sizeof(gParse));
  gParse.db = gDb;
}

void tearDown(void) {
  if( gDb ){
    sqlite3_close(gDb);
    gDb = NULL;
  }
}

/* Tests */

void test_renameColumnIdlistNames_null_list_noop(void){
  RenameCtx ctx, ctxBefore;
  memset(&ctx, 0, sizeof(ctx));
  memcpy(&ctxBefore, &ctx, sizeof(ctx));

  test_renameColumnIdlistNames(&gParse, &ctx, NULL, "x");

  TEST_ASSERT_EQUAL_MEMORY(&ctxBefore, &ctx, sizeof(ctx));
}

void test_renameColumnIdlistNames_empty_list_noop(void){
  RenameCtx ctx, ctxBefore;
  memset(&ctx, 0, sizeof(ctx));
  memcpy(&ctxBefore, &ctx, sizeof(ctx));

  IdList *pList = (IdList*)sqlite3DbMallocZero(gParse.db, sizeof(IdList));
  TEST_ASSERT_NOT_NULL(pList);
  /* pList->nId is 0 and pList->a is NULL due to MallocZero */

  test_renameColumnIdlistNames(&gParse, &ctx, pList, "anything");

  TEST_ASSERT_EQUAL_MEMORY(&ctxBefore, &ctx, sizeof(ctx));

  sqlite3IdListDelete(gParse.db, pList);
}

void test_renameColumnIdlistNames_no_match_ctx_unchanged(void){
  const char *names[] = {"alpha","beta","gamma"};
  IdList *pList = makeIdList(&gParse, names, 3);

  RenameCtx ctx, ctxBefore;
  memset(&ctx, 0, sizeof(ctx));
  memcpy(&ctxBefore, &ctx, sizeof(ctx));

  test_renameColumnIdlistNames(&gParse, &ctx, pList, "delta");

  TEST_ASSERT_EQUAL_MEMORY(&ctxBefore, &ctx, sizeof(ctx));

  sqlite3IdListDelete(gParse.db, pList);
}

void test_renameColumnIdlistNames_single_match_exact_no_crash(void){
  const char *names[] = {"alpha","beta","gamma"};
  IdList *pList = makeIdList(&gParse, names, 3);

  RenameCtx ctx;
  memset(&ctx, 0, sizeof(ctx));

  /* Should not crash; we do not assert internal rename-token effects */
  test_renameColumnIdlistNames(&gParse, &ctx, pList, "beta");

  /* Ensure input list is intact */
  TEST_ASSERT_EQUAL_INT(3, pList->nId);
  TEST_ASSERT_NOT_NULL(pList->a);
  TEST_ASSERT_NOT_NULL(pList->a[1].zName);
  TEST_ASSERT_EQUAL_STRING("beta", pList->a[1].zName);

  sqlite3IdListDelete(gParse.db, pList);
}

void test_renameColumnIdlistNames_single_match_case_insensitive_no_crash(void){
  const char *names[] = {"alpha","BeTa","gamma"};
  IdList *pList = makeIdList(&gParse, names, 3);

  RenameCtx ctx;
  memset(&ctx, 0, sizeof(ctx));

  test_renameColumnIdlistNames(&gParse, &ctx, pList, "bEtA");

  /* Input remains intact */
  TEST_ASSERT_EQUAL_INT(3, pList->nId);
  TEST_ASSERT_NOT_NULL(pList->a[1].zName);
  TEST_ASSERT_EQUAL_STRING("BeTa", pList->a[1].zName);

  sqlite3IdListDelete(gParse.db, pList);
}

void test_renameColumnIdlistNames_multiple_matches_no_crash(void){
  const char *names[] = {"a","A","b","a","c","A"};
  IdList *pList = makeIdList(&gParse, names, 6);

  RenameCtx ctx;
  memset(&ctx, 0, sizeof(ctx));

  test_renameColumnIdlistNames(&gParse, &ctx, pList, "a");

  /* Validate the list content remains correct */
  TEST_ASSERT_EQUAL_INT(6, pList->nId);
  TEST_ASSERT_EQUAL_STRING("a", pList->a[0].zName);
  TEST_ASSERT_EQUAL_STRING("A", pList->a[1].zName);
  TEST_ASSERT_EQUAL_STRING("a", pList->a[3].zName);
  TEST_ASSERT_EQUAL_STRING("A", pList->a[5].zName);

  sqlite3IdListDelete(gParse.db, pList);
}

void test_renameColumnIdlistNames_long_strings_and_mixed_case_no_crash(void){
  const char *names[] = {
    "MiXeDCaSeName",
    "another_name_with_underscores",
    "yetAnotherName123",
    "LONGNAME_LONGNAME_LONGNAME"
  };
  IdList *pList = makeIdList(&gParse, names, 4);

  RenameCtx ctx;
  memset(&ctx, 0, sizeof(ctx));

  test_renameColumnIdlistNames(&gParse, &ctx, pList, "mixedcasename"); /* matches first */

  /* Sanity check list intact */
  TEST_ASSERT_EQUAL_STRING("MiXeDCaSeName", pList->a[0].zName);

  sqlite3IdListDelete(gParse.db, pList);
}

void test_renameColumnIdlistNames_large_list_no_match_no_crash(void){
  enum { N = 200 };
  const char *arr[N];
  char *storage[N];
  for(int i=0; i<N; i++){
    char buf[32];
    sqlite3_snprintf(sizeof(buf), buf, "col%d", i);
    storage[i] = sqlite3_mprintf("%s", buf);
    TEST_ASSERT_NOT_NULL(storage[i]);
    arr[i] = storage[i];
  }

  IdList *pList = makeIdList(&gParse, arr, N);

  RenameCtx ctx, ctxBefore;
  memset(&ctx, 0, sizeof(ctx));
  memcpy(&ctxBefore, &ctx, sizeof(ctx));

  test_renameColumnIdlistNames(&gParse, &ctx, pList, "no_such_column");

  TEST_ASSERT_EQUAL_MEMORY(&ctxBefore, &ctx, sizeof(ctx));

  sqlite3IdListDelete(gParse.db, pList);
  for(int i=0; i<N; i++){
    sqlite3_free(storage[i]);
  }
}

int main(void){
  UNITY_BEGIN();

  RUN_TEST(test_renameColumnIdlistNames_null_list_noop);
  RUN_TEST(test_renameColumnIdlistNames_empty_list_noop);
  RUN_TEST(test_renameColumnIdlistNames_no_match_ctx_unchanged);
  RUN_TEST(test_renameColumnIdlistNames_single_match_exact_no_crash);
  RUN_TEST(test_renameColumnIdlistNames_single_match_case_insensitive_no_crash);
  RUN_TEST(test_renameColumnIdlistNames_multiple_matches_no_crash);
  RUN_TEST(test_renameColumnIdlistNames_long_strings_and_mixed_case_no_crash);
  RUN_TEST(test_renameColumnIdlistNames_large_list_no_match_no_crash);

  return UNITY_END();
}