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

/* Wrapper for the static function under test (provided by the build) */
extern void test_renameWalkTrigger(Walker *pWalker, Trigger *pTrigger);

/* Global counters/state for callbacks */
typedef struct CallbackState {
  /* Totals */
  int nExprCalls;
  int nSelectCalls;

  /* Specific node hits */
  int hitWhen;
  int hitWhere;
  int hitList1;
  int hitList2;
  int hitUpTarget1;
  int hitUpSet1;
  int hitUpWhere;
  int hitUpTargetWhere;
  int hitSel1;
  int hitSel2;

  /* Unexpected nodes */
  int unexpectedExpr;
  int unexpectedSelect;

  /* Expected node pointers */
  Expr *pWhen;
  Expr *pWhere;
  Expr *pList1;
  Expr *pList2;
  Expr *pUpTarget1;
  Expr *pUpSet1;
  Expr *pUpWhere;
  Expr *pUpTargetWhere;
  Select *pSel1;
  Select *pSel2;
} CallbackState;

static CallbackState gCb;

/* Walker callbacks */
static int testExprCallback(Walker *pWalker, Expr *pExpr){
  (void)pWalker;
  gCb.nExprCalls++;
  if( pExpr==gCb.pWhen ) gCb.hitWhen++;
  else if( pExpr==gCb.pWhere ) gCb.hitWhere++;
  else if( pExpr==gCb.pList1 ) gCb.hitList1++;
  else if( pExpr==gCb.pList2 ) gCb.hitList2++;
  else if( pExpr==gCb.pUpTarget1 ) gCb.hitUpTarget1++;
  else if( pExpr==gCb.pUpSet1 ) gCb.hitUpSet1++;
  else if( pExpr==gCb.pUpWhere ) gCb.hitUpWhere++;
  else if( pExpr==gCb.pUpTargetWhere ) gCb.hitUpTargetWhere++;
  else gCb.unexpectedExpr++;
  return WRC_Continue;
}
static int testSelectCallback(Walker *pWalker, Select *pSelect){
  (void)pWalker;
  gCb.nSelectCalls++;
  if( pSelect==gCb.pSel1 ) gCb.hitSel1++;
  else if( pSelect==gCb.pSel2 ) gCb.hitSel2++;
  else gCb.unexpectedSelect++;
  return WRC_Continue;
}

/* Helpers to create minimal nodes */
static Expr *mkLeafExpr(void){
  Expr *p = (Expr*)sqlite3_malloc(sizeof(Expr));
  TEST_ASSERT_NOT_NULL_MESSAGE(p, "sqlite3_malloc Expr failed");
  memset(p, 0, sizeof(Expr));
  p->op = TK_NULL; /* A safe leaf opcode */
  return p;
}
static Select *mkEmptySelect(void){
  Select *p = (Select*)sqlite3_malloc(sizeof(Select));
  TEST_ASSERT_NOT_NULL_MESSAGE(p, "sqlite3_malloc Select failed");
  memset(p, 0, sizeof(Select));
  return p;
}
static ExprList *mkExprList1(Expr *e1){
  ExprList *p = (ExprList*)sqlite3_malloc(sizeof(ExprList));
  TEST_ASSERT_NOT_NULL_MESSAGE(p, "sqlite3_malloc ExprList failed");
  memset(p, 0, sizeof(ExprList));
  p->nExpr = 1;
  p->nAlloc = 1;
  p->a = (ExprList_item*)sqlite3_malloc(sizeof(ExprList_item) * 1);
  TEST_ASSERT_NOT_NULL_MESSAGE(p->a, "sqlite3_malloc ExprList_item[1] failed");
  memset(p->a, 0, sizeof(ExprList_item) * 1);
  p->a[0].pExpr = e1;
  return p;
}
static ExprList *mkExprList2(Expr *e1, Expr *e2){
  ExprList *p = (ExprList*)sqlite3_malloc(sizeof(ExprList));
  TEST_ASSERT_NOT_NULL_MESSAGE(p, "sqlite3_malloc ExprList failed");
  memset(p, 0, sizeof(ExprList));
  p->nExpr = 2;
  p->nAlloc = 2;
  p->a = (ExprList_item*)sqlite3_malloc(sizeof(ExprList_item) * 2);
  TEST_ASSERT_NOT_NULL_MESSAGE(p->a, "sqlite3_malloc ExprList_item[2] failed");
  memset(p->a, 0, sizeof(ExprList_item) * 2);
  p->a[0].pExpr = e1;
  p->a[1].pExpr = e2;
  return p;
}
static void freeExprList(ExprList *p){
  if( p ){
    sqlite3_free(p->a);
    sqlite3_free(p);
  }
}

/* Unity fixtures */
void setUp(void){
  memset(&gCb, 0, sizeof(gCb));
}
void tearDown(void){
  /* Nothing global to cleanup */
}

/* Test: No fields set => no callbacks */
void test_renameWalkTrigger_nulls(void){
  Trigger *tr = (Trigger*)sqlite3_malloc(sizeof(Trigger));
  TEST_ASSERT_NOT_NULL(tr);
  memset(tr, 0, sizeof(Trigger));

  Walker w;
  memset(&w, 0, sizeof(w));
  w.xExprCallback = testExprCallback;
  w.xSelectCallback = testSelectCallback;

  test_renameWalkTrigger(&w, tr);

  TEST_ASSERT_EQUAL_INT(0, gCb.nExprCalls);
  TEST_ASSERT_EQUAL_INT(0, gCb.nSelectCalls);
  TEST_ASSERT_EQUAL_INT(0, gCb.unexpectedExpr);
  TEST_ASSERT_EQUAL_INT(0, gCb.unexpectedSelect);

  sqlite3_free(tr);
}

/* Test: WHEN, SELECT, WHERE, and ExprList are all visited */
void test_renameWalkTrigger_basic_fields(void){
  /* Build nodes */
  Expr *eWhen = mkLeafExpr();
  Expr *eWhere = mkLeafExpr();
  Expr *eList1 = mkLeafExpr();
  Expr *eList2 = mkLeafExpr();
  ExprList *pList = mkExprList2(eList1, eList2);
  Select *pSel = mkEmptySelect();

  /* Build step */
  TriggerStep *st = (TriggerStep*)sqlite3_malloc(sizeof(TriggerStep));
  TEST_ASSERT_NOT_NULL(st);
  memset(st, 0, sizeof(TriggerStep));
  st->pSelect = pSel;
  st->pWhere = eWhere;
  st->pExprList = pList;

  /* Build trigger */
  Trigger *tr = (Trigger*)sqlite3_malloc(sizeof(Trigger));
  TEST_ASSERT_NOT_NULL(tr);
  memset(tr, 0, sizeof(Trigger));
  tr->pWhen = eWhen;
  tr->step_list = st;

  /* Set expected pointers */
  gCb.pWhen = eWhen;
  gCb.pWhere = eWhere;
  gCb.pList1 = eList1;
  gCb.pList2 = eList2;
  gCb.pSel1 = pSel;

  Walker w;
  memset(&w, 0, sizeof(w));
  w.xExprCallback = testExprCallback;
  w.xSelectCallback = testSelectCallback;

  test_renameWalkTrigger(&w, tr);

  /* Expect: 1 WHEN + 1 WHERE + 2 list exprs = 4 expr callbacks */
  TEST_ASSERT_EQUAL_INT(4, gCb.nExprCalls);
  TEST_ASSERT_EQUAL_INT(1, gCb.nSelectCalls);

  TEST_ASSERT_EQUAL_INT(1, gCb.hitWhen);
  TEST_ASSERT_EQUAL_INT(1, gCb.hitWhere);
  TEST_ASSERT_EQUAL_INT(1, gCb.hitList1);
  TEST_ASSERT_EQUAL_INT(1, gCb.hitList2);
  TEST_ASSERT_EQUAL_INT(1, gCb.hitSel1);

  TEST_ASSERT_EQUAL_INT(0, gCb.unexpectedExpr);
  TEST_ASSERT_EQUAL_INT(0, gCb.unexpectedSelect);

  /* Cleanup */
  sqlite3_free(eWhen);
  sqlite3_free(eWhere);
  sqlite3_free(eList1);
  sqlite3_free(eList2);
  freeExprList(pList);
  sqlite3_free(pSel);
  sqlite3_free(st);
  sqlite3_free(tr);
}

/* Test: Upsert-related fields are visited */
void test_renameWalkTrigger_upsert_fields(void){
  /* Build upsert components */
  Expr *eUpTarget1 = mkLeafExpr();
  Expr *eUpSet1 = mkLeafExpr();
  Expr *eUpWhere = mkLeafExpr();
  Expr *eUpTargetWhere = mkLeafExpr();
  ExprList *pTarget = mkExprList1(eUpTarget1);
  ExprList *pSet = mkExprList1(eUpSet1);

  Upsert *pUp = (Upsert*)sqlite3_malloc(sizeof(Upsert));
  TEST_ASSERT_NOT_NULL(pUp);
  memset(pUp, 0, sizeof(Upsert));
  pUp->pUpsertTarget = pTarget;
  pUp->pUpsertSet = pSet;
  pUp->pUpsertWhere = eUpWhere;
  pUp->pUpsertTargetWhere = eUpTargetWhere;

  /* Step with only Upsert */
  TriggerStep *st = (TriggerStep*)sqlite3_malloc(sizeof(TriggerStep));
  TEST_ASSERT_NOT_NULL(st);
  memset(st, 0, sizeof(TriggerStep));
  st->pUpsert = pUp;

  Trigger *tr = (Trigger*)sqlite3_malloc(sizeof(Trigger));
  TEST_ASSERT_NOT_NULL(tr);
  memset(tr, 0, sizeof(Trigger));
  tr->step_list = st;

  /* Expected pointers */
  gCb.pUpTarget1 = eUpTarget1;
  gCb.pUpSet1 = eUpSet1;
  gCb.pUpWhere = eUpWhere;
  gCb.pUpTargetWhere = eUpTargetWhere;

  Walker w;
  memset(&w, 0, sizeof(w));
  w.xExprCallback = testExprCallback;
  w.xSelectCallback = testSelectCallback;

  test_renameWalkTrigger(&w, tr);

  /* Expect: 1 target expr + 1 set expr + where + targetWhere = 4 exprs */
  TEST_ASSERT_EQUAL_INT(4, gCb.nExprCalls);
  TEST_ASSERT_EQUAL_INT(0, gCb.nSelectCalls);

  TEST_ASSERT_EQUAL_INT(1, gCb.hitUpTarget1);
  TEST_ASSERT_EQUAL_INT(1, gCb.hitUpSet1);
  TEST_ASSERT_EQUAL_INT(1, gCb.hitUpWhere);
  TEST_ASSERT_EQUAL_INT(1, gCb.hitUpTargetWhere);

  TEST_ASSERT_EQUAL_INT(0, gCb.unexpectedExpr);
  TEST_ASSERT_EQUAL_INT(0, gCb.unexpectedSelect);

  /* Cleanup */
  sqlite3_free(eUpTarget1);
  sqlite3_free(eUpSet1);
  sqlite3_free(eUpWhere);
  sqlite3_free(eUpTargetWhere);
  freeExprList(pTarget);
  freeExprList(pSet);
  sqlite3_free(pUp);
  sqlite3_free(st);
  sqlite3_free(tr);
}

/* Test: Multiple steps are iterated (one with SELECT, next with WHERE) */
void test_renameWalkTrigger_multiple_steps(void){
  Select *pSel = mkEmptySelect();
  Expr *eWhere2 = mkLeafExpr();

  TriggerStep *st1 = (TriggerStep*)sqlite3_malloc(sizeof(TriggerStep));
  TEST_ASSERT_NOT_NULL(st1);
  memset(st1, 0, sizeof(TriggerStep));
  st1->pSelect = pSel;

  TriggerStep *st2 = (TriggerStep*)sqlite3_malloc(sizeof(TriggerStep));
  TEST_ASSERT_NOT_NULL(st2);
  memset(st2, 0, sizeof(TriggerStep));
  st2->pWhere = eWhere2;

  st1->pNext = st2;

  Trigger *tr = (Trigger*)sqlite3_malloc(sizeof(Trigger));
  TEST_ASSERT_NOT_NULL(tr);
  memset(tr, 0, sizeof(Trigger));
  tr->step_list = st1;

  /* Expected pointers */
  gCb.pSel1 = pSel;
  gCb.pWhere = eWhere2;

  Walker w;
  memset(&w, 0, sizeof(w));
  w.xExprCallback = testExprCallback;
  w.xSelectCallback = testSelectCallback;

  test_renameWalkTrigger(&w, tr);

  TEST_ASSERT_EQUAL_INT(1, gCb.nSelectCalls);
  TEST_ASSERT_EQUAL_INT(1, gCb.nExprCalls);
  TEST_ASSERT_EQUAL_INT(1, gCb.hitSel1);
  TEST_ASSERT_EQUAL_INT(1, gCb.hitWhere);
  TEST_ASSERT_EQUAL_INT(0, gCb.unexpectedExpr);
  TEST_ASSERT_EQUAL_INT(0, gCb.unexpectedSelect);

  /* Cleanup */
  sqlite3_free(pSel);
  sqlite3_free(eWhere2);
  sqlite3_free(st1);
  sqlite3_free(st2);
  sqlite3_free(tr);
}

int main(void){
  UNITY_BEGIN();
  RUN_TEST(test_renameWalkTrigger_nulls);
  RUN_TEST(test_renameWalkTrigger_basic_fields);
  RUN_TEST(test_renameWalkTrigger_upsert_fields);
  RUN_TEST(test_renameWalkTrigger_multiple_steps);
  return UNITY_END();
}