// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

#include "vm/hash_map.h"
#include "platform/assert.h"
#include "vm/unit_test.h"

namespace dart {

class TestValue {
 public:
  explicit TestValue(intptr_t x) : x_(x) {}
  intptr_t Hashcode() const { return x_ & 1; }
  bool Equals(TestValue* other) { return x_ == other->x_; }

 private:
  intptr_t x_;
};

TEST_CASE(DirectChainedHashMap) {
  DirectChainedHashMap<PointerKeyValueTrait<TestValue> > map;
  EXPECT(map.IsEmpty());
  TestValue v1(0);
  TestValue v2(1);
  TestValue v3(0);
  map.Insert(&v1);
  EXPECT(map.LookupValue(&v1) == &v1);
  map.Insert(&v2);
  EXPECT(map.LookupValue(&v1) == &v1);
  EXPECT(map.LookupValue(&v2) == &v2);
  EXPECT(map.LookupValue(&v3) == &v1);
  EXPECT(map.Remove(&v1));
  EXPECT(map.Lookup(&v1) == NULL);
  map.Insert(&v1);
  DirectChainedHashMap<PointerKeyValueTrait<TestValue> > map2(map);
  EXPECT(map2.LookupValue(&v1) == &v1);
  EXPECT(map2.LookupValue(&v2) == &v2);
  EXPECT(map2.LookupValue(&v3) == &v1);
}

TEST_CASE(DirectChainedHashMapInsertRemove) {
  DirectChainedHashMap<PointerKeyValueTrait<TestValue> > map;
  EXPECT(map.IsEmpty());
  TestValue v1(1);
  TestValue v2(3);  // Note: v1, v2, v3 should have the same hash.
  TestValue v3(5);

  // Start with adding and removing the same element.
  map.Insert(&v1);
  EXPECT(map.LookupValue(&v1) == &v1);
  EXPECT(map.Remove(&v1));
  EXPECT(map.Lookup(&v1) == NULL);

  // Inserting v2 first should put it at the head of the list.
  map.Insert(&v2);
  map.Insert(&v1);
  EXPECT(map.LookupValue(&v2) == &v2);
  EXPECT(map.LookupValue(&v1) == &v1);

  // Check to see if removing the head of the list causes issues.
  EXPECT(map.Remove(&v2));
  EXPECT(map.Lookup(&v2) == NULL);
  EXPECT(map.LookupValue(&v1) == &v1);

  // Reinsert v2, which will place it at the back of the hash map list.
  map.Insert(&v2);
  EXPECT(map.LookupValue(&v2) == &v2);

  // Remove from the back of the hash map list.
  EXPECT(map.Remove(&v2));
  EXPECT(map.Lookup(&v2) == NULL);
  EXPECT(map.Remove(&v1));
  EXPECT(map.Lookup(&v1) == NULL);

  // Check to see that removing an invalid element returns false.
  EXPECT(!map.Remove(&v1));

  // One last case: remove from the middle of a hash map list.
  map.Insert(&v1);
  map.Insert(&v2);
  map.Insert(&v3);

  EXPECT(map.LookupValue(&v1) == &v1);
  EXPECT(map.LookupValue(&v2) == &v2);
  EXPECT(map.LookupValue(&v3) == &v3);

  EXPECT(map.Remove(&v2));
  EXPECT(map.LookupValue(&v1) == &v1);
  EXPECT(map.Lookup(&v2) == NULL);
  EXPECT(map.LookupValue(&v3) == &v3);

  EXPECT(map.Remove(&v1));
  EXPECT(map.Remove(&v3));

  EXPECT(map.IsEmpty());
}

TEST_CASE(MallocDirectChainedHashMap) {
  MallocDirectChainedHashMap<PointerKeyValueTrait<TestValue> > map;
  EXPECT(map.IsEmpty());
  TestValue v1(0);
  TestValue v2(1);
  TestValue v3(0);
  map.Insert(&v1);
  EXPECT(map.LookupValue(&v1) == &v1);
  map.Insert(&v2);
  EXPECT(map.LookupValue(&v1) == &v1);
  EXPECT(map.LookupValue(&v2) == &v2);
  EXPECT(map.LookupValue(&v3) == &v1);
  MallocDirectChainedHashMap<PointerKeyValueTrait<TestValue> > map2(map);
  EXPECT(map2.LookupValue(&v1) == &v1);
  EXPECT(map2.LookupValue(&v2) == &v2);
  EXPECT(map2.LookupValue(&v3) == &v1);
}

class IntptrPair {
 public:
  IntptrPair() : first_(-1), second_(-1) {}
  IntptrPair(intptr_t first, intptr_t second)
      : first_(first), second_(second) {}

  intptr_t first() const { return first_; }
  intptr_t second() const { return second_; }

  bool operator==(const IntptrPair& other) {
    return (first_ == other.first_) && (second_ == other.second_);
  }

  bool operator!=(const IntptrPair& other) {
    return (first_ != other.first_) || (second_ != other.second_);
  }

 private:
  intptr_t first_;
  intptr_t second_;
};

TEST_CASE(DirectChainedHashMapIterator) {
  IntptrPair p1(1, 1);
  IntptrPair p2(2, 2);
  IntptrPair p3(3, 3);
  IntptrPair p4(4, 4);
  IntptrPair p5(5, 5);
  DirectChainedHashMap<NumbersKeyValueTrait<IntptrPair> > map;
  EXPECT(map.IsEmpty());
  DirectChainedHashMap<NumbersKeyValueTrait<IntptrPair> >::Iterator it =
      map.GetIterator();
  EXPECT(it.Next() == NULL);
  it.Reset();

  map.Insert(p1);
  EXPECT(*it.Next() == p1);
  it.Reset();

  map.Insert(p2);
  map.Insert(p3);
  map.Insert(p4);
  map.Insert(p5);
  intptr_t count = 0;
  intptr_t sum = 0;
  while (true) {
    IntptrPair* p = it.Next();
    if (p == NULL) {
      break;
    }
    count++;
    sum += p->second();
  }

  EXPECT(count == 5);
  EXPECT(sum == 15);
}

}  // namespace dart