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

/* The test wrapper for the static function is expected to be provided */
extern int test_renameTableExprCb(Walker *pWalker, Expr *pExpr);

static sqlite3 *gDb = NULL;

void setUp(void) {
  int rc = sqlite3_open(":memory:", &gDb);
  TEST_ASSERT_EQUAL_INT(SQLITE_OK, rc);
  TEST_ASSERT_NOT_NULL(gDb);
}

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

/* Helper to initialize a minimal Parse object */
static void initParse(Parse *pParse){
  memset(pParse, 0, sizeof(*pParse));
  pParse->db = gDb;
}

/* Helper to initialize a minimal Walker with a RenameCtx */
static void initWalkerWithRenameCtx(Walker *pWalker, RenameCtx *pCtx, Parse *pParse){
  memset(pWalker, 0, sizeof(*pWalker));
  memset(pCtx, 0, sizeof(*pCtx));
  pWalker->pParse = pParse;
  pWalker->u.pRename = pCtx;
}

/* Helper to initialize an Expr with TK_COLUMN and specified Table* */
static void initColumnExprWithTab(Expr *pExpr, Table *pTab){
  memset(pExpr, 0, sizeof(*pExpr));
  pExpr->op = TK_COLUMN;
  /* ExprUseYTab() is true for TK_COLUMN, so fill y.pTab */
  pExpr->y.pTab = pTab;
}

/* 1) Non-column expression: ensure return value is WRC_Continue and no crash */
void test_renameTableExprCb_returns_continue_for_non_column(void){
  Parse sParse; initParse(&sParse);
  Walker sWalker; RenameCtx sCtx;
  initWalkerWithRenameCtx(&sWalker, &sCtx, &sParse);

  Expr sExpr;
  memset(&sExpr, 0, sizeof(sExpr));
  sExpr.op = TK_INTEGER; /* Not TK_COLUMN, so condition should be false */

  int rc = test_renameTableExprCb(&sWalker, &sExpr);
  TEST_ASSERT_EQUAL_INT(WRC_Continue, rc);
}

/* 2) TK_COLUMN but pExpr->y.pTab does not match RenameCtx.pTab: no-op, returns continue */
void test_renameTableExprCb_no_action_when_table_mismatch(void){
  Parse sParse; initParse(&sParse);
  Walker sWalker; RenameCtx sCtx;
  initWalkerWithRenameCtx(&sWalker, &sCtx, &sParse);

  Table tabA, tabB;
  memset(&tabA, 0, sizeof(tabA));
  memset(&tabB, 0, sizeof(tabB));
  sCtx.pTab = &tabA; /* Context expects tabA */

  Expr sExpr;
  initColumnExprWithTab(&sExpr, &tabB); /* Expression references tabB */

  int rc = test_renameTableExprCb(&sWalker, &sExpr);
  TEST_ASSERT_EQUAL_INT(WRC_Continue, rc);
}

/* 3) TK_COLUMN and pExpr->y.pTab matches RenameCtx.pTab: should trigger renameTokenFind and return WRC_Continue */
void test_renameTableExprCb_triggers_on_match(void){
  Parse sParse; initParse(&sParse);
  Walker sWalker; RenameCtx sCtx;
  initWalkerWithRenameCtx(&sWalker, &sCtx, &sParse);

  Table tabT;
  memset(&tabT, 0, sizeof(tabT));
  sCtx.pTab = &tabT;

  Expr sExpr;
  initColumnExprWithTab(&sExpr, &tabT);

  int rc = test_renameTableExprCb(&sWalker, &sExpr);
  TEST_ASSERT_EQUAL_INT(WRC_Continue, rc);
}

/* 4) Multiple sequential invocations with mixed inputs to ensure robustness and idempotent return */
void test_renameTableExprCb_multiple_sequential_calls(void){
  Parse sParse; initParse(&sParse);
  Walker sWalker; RenameCtx sCtx;
  initWalkerWithRenameCtx(&sWalker, &sCtx, &sParse);

  Table tab1, tab2;
  memset(&tab1, 0, sizeof(tab1));
  memset(&tab2, 0, sizeof(tab2));
  sCtx.pTab = &tab1;

  Expr e1, e2, e3;
  /* Non-column: should be ignored */
  memset(&e1, 0, sizeof(e1));
  e1.op = TK_NULL;

  /* Column but mismatch: should be ignored */
  initColumnExprWithTab(&e2, &tab2);

  /* Column and match: should trigger renameTokenFind */
  initColumnExprWithTab(&e3, &tab1);

  TEST_ASSERT_EQUAL_INT(WRC_Continue, test_renameTableExprCb(&sWalker, &e1));
  TEST_ASSERT_EQUAL_INT(WRC_Continue, test_renameTableExprCb(&sWalker, &e2));
  TEST_ASSERT_EQUAL_INT(WRC_Continue, test_renameTableExprCb(&sWalker, &e3));
}

int main(void) {
  UNITY_BEGIN();
  RUN_TEST(test_renameTableExprCb_returns_continue_for_non_column);
  RUN_TEST(test_renameTableExprCb_no_action_when_table_mismatch);
  RUN_TEST(test_renameTableExprCb_triggers_on_match);
  RUN_TEST(test_renameTableExprCb_multiple_sequential_calls);
  return UNITY_END();
}