// Copyright 2018 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include <lib/fit/defer.h>

#include <string_view>
#include <utility>

#include <fbl/string_printf.h>
#include <zxtest/base/log-sink.h>
#include <zxtest/base/runner.h>

namespace zxtest {

const Runner::Options Runner::kDefaultOptions;

namespace internal {

TestDriverImpl::TestDriverImpl() = default;
TestDriverImpl::~TestDriverImpl() = default;

void TestDriverImpl::Skip() { status_ = TestStatus::kSkipped; }

bool TestDriverImpl::Continue() const {
  return !current_test_has_fatal_failures_ && status_ != TestStatus::kSkipped;
}

void TestDriverImpl::OnTestStart(const TestCase& test_case, const TestInfo& test_info) {
  status_ = TestStatus::kPassed;
}

void TestDriverImpl::OnTestSkip(const TestCase& test_case, const TestInfo& test_info) { Reset(); }

void TestDriverImpl::OnTestSuccess(const TestCase& test_case, const TestInfo& test_info) {
  Reset();
}

void TestDriverImpl::OnTestFailure(const TestCase& test_case, const TestInfo& test_info) {
  Reset();
}

void TestDriverImpl::OnAssertion(const Assertion& assertion) {
  if (asserts_enabled_) {
    status_ = TestStatus::kFailed;
    current_test_has_any_failures_ = true;
    current_test_has_fatal_failures_ = assertion.is_fatal();
    had_any_failures_ = true;
  }
}

void TestDriverImpl::Reset() {
  current_test_has_fatal_failures_ = false;
  current_test_has_any_failures_ = false;
  status_ = TestStatus::kPassed;
}

}  // namespace internal

Runner::Runner(Reporter&& reporter) : reporter_(std::move(reporter)) {
  event_broadcaster_.Subscribe(&test_driver_);
  event_broadcaster_.Subscribe(&reporter_);
}
Runner::~Runner() = default;

TestRef Runner::RegisterTest(const fbl::String& test_case_name, const fbl::String& test_name,
                             const SourceLocation& location, internal::TestFactory factory,
                             internal::SetUpTestCaseFn set_up,
                             internal::TearDownTestCaseFn tear_down) {
  ZX_ASSERT_MSG(!test_case_name.empty(), "test_case_name cannot be an empty string.");
  ZX_ASSERT_MSG(!test_name.empty(), "test_name cannot be an empty string.");

  // TODO(gevalentino): replace by std::find.
  TestCase* target_test_case = nullptr;
  TestRef test_ref;

  for (auto& test_case : test_cases_) {
    if (test_case.name() == test_case_name) {
      target_test_case = &test_case;
      break;
    }
    test_ref.test_case_index++;
  }

  // If there is no existing test case with |test_case_name|, create a new one.
  if (target_test_case == nullptr) {
    test_cases_.push_back(TestCase(test_case_name, std::move(set_up), std::move(tear_down)));
    target_test_case = &test_cases_[test_cases_.size() - 1];
  }

  test_ref.test_index = target_test_case->TestCount();
  ZX_ASSERT_MSG(target_test_case->RegisterTest(test_name, location, std::move(factory)),
                "Test Registration failed.");
  summary_.registered_test_count++;
  summary_.registered_test_case_count = test_cases_.size();

  return test_ref;
}

int Runner::Run(const Runner::Options& options) {
  is_running_ = true;
  RegisterParameterizedTests();

  options_ = &options;
  auto reset_options = fit::defer([this]() { options_ = nullptr; });
  summary_.total_iterations = options.repeat;
  EnforceOptions(options);

  event_broadcaster_.OnProgramStart(*this);
  bool end_execution = false;
  for (int i = 0; (i < options.repeat || options.repeat == -1) && !end_execution; ++i) {
    event_broadcaster_.OnIterationStart(*this, i);
    event_broadcaster_.OnEnvironmentSetUp(*this);
    // Set them up in order.
    for (auto& environment : environments_) {
      environment->SetUp();
    }

    for (auto& test_case : test_cases_) {
      if (options.shuffle) {
        test_case.Shuffle(options.seed);
      }

      test_case.Run(&event_broadcaster_, &test_driver_);

      // If there was any kind of failure, we should stop executing any other
      // test case and just finish. TearDown do get called, this is treated
      // as if everything ended here.
      if ((options.break_on_failure && test_driver_.HadAnyFailures()) || fatal_error_) {
        end_execution = true;
        break;
      }

      if (options.shuffle) {
        test_case.UnShuffle();
      }
    }
    event_broadcaster_.OnEnvironmentTearDown(*this);

    // Tear them down in reverse order
    for (size_t i = environments_.size(); i > 0; --i) {
      environments_[i - 1]->TearDown();
    }
    event_broadcaster_.OnIterationEnd(*this, i);
  }
  event_broadcaster_.OnProgramEnd(*this);
  is_running_ = false;
  return test_driver_.HadAnyFailures() ? -1 : 0;
}

void Runner::List(const Runner::Options& options) {
  RegisterParameterizedTests();

  options_ = &options;
  auto reset_options = fit::defer([this]() { options_ = nullptr; });
  summary_.total_iterations = options.repeat;
  EnforceOptions(options);

  for (const auto& test_case : test_cases_) {
    if (test_case.MatchingTestCount() == 0) {
      continue;
    }

    reporter_.mutable_log_sink()->Write("%s\n", test_case.name().c_str());
    for (size_t i = 0; i < test_case.MatchingTestCount(); ++i) {
      reporter_.mutable_log_sink()->Write("  .%s\n",
                                          test_case.GetMatchingTestInfo(i).name().c_str());
    }
  }
}

void Runner::EnforceOptions(const Runner::Options& options) {
  summary_.active_test_count = 0;
  summary_.active_test_case_count = 0;
  fbl::String filter_pattern = options.filter;
  const FilterOp filter_op = {.pattern = filter_pattern, .run_disabled = options.run_disabled};
  for (auto& test_case : test_cases_) {
    // TODO(gevalentino): replace with filter function.
    test_case.Filter(filter_op);
    if (test_case.MatchingTestCount() > 0) {
      summary_.active_test_case_count++;
      summary_.active_test_count += test_case.MatchingTestCount();
      test_case.SetReturnOnFailure(options.break_on_failure);
    }
  }
}

void Runner::NotifyAssertion(const Assertion& assertion) {
  event_broadcaster_.OnAssertion(assertion);
}

void Runner::SkipCurrent(const Message& message) {
  event_broadcaster_.OnMessage(message);
  test_driver_.Skip();
}

Runner* Runner::GetInstance() {
  static Runner runner = Runner(Reporter(std::make_unique<FileLogSink>(stdout)));
  return &runner;
}

int RunAllTests(int argc, char** argv) {
  fbl::Vector<fbl::String> errors;
  LogSink* log_sink = Runner::GetInstance()->mutable_reporter()->mutable_log_sink();
  Runner::Options options = Runner::Options::FromArgs(argc, argv, &errors);

  if (!errors.is_empty()) {
    for (const auto& error : errors) {
      log_sink->Write("%s\n", error.c_str());
    }
    options.help = true;
  }

  // Errors will always set help to true.
  if (options.help) {
    Runner::Options::Usage(argv[0], log_sink);
    return errors.is_empty();
  }

  if (options.list) {
    Runner::GetInstance()->List(options);
    return 0;
  }

  return Runner::GetInstance()->Run(options);
}

namespace {
bool MatchPatterns(std::string_view pattern, std::string_view str) {
  static constexpr auto match_pattern = [](const char* pattern, const char* str) -> bool {
    auto advance = [](const char* pattern, const char* str, auto& self) -> bool {
      switch (*pattern) {
        // Single character matching for gTest
        case '?':
          return *str != '\0' && self(pattern + 1, str + 1, self);
        // Wild card matches anything.
        case '*':
          return (*str != '\0' && self(pattern, str + 1, self)) || self(pattern + 1, str, self);
        // Pattern completed or another pattern in the list.
        case '\0':
        case ':':
          return *str == '\0';
        // 1:1 match
        default:
          return *str == *pattern && self(pattern + 1, str + 1, self);
      };
    };
    return advance(pattern, str, advance);
  };

  if (pattern.empty()) {
    return true;
  }

  bool has_next = true;
  const char* curr_pattern = pattern.data();
  while (has_next) {
    if (match_pattern(curr_pattern, str.data())) {
      return true;
    }
    curr_pattern = strchr(curr_pattern, ':');
    has_next = (curr_pattern != nullptr);
    // Skip ':'
    if (has_next) {
      curr_pattern++;
    }
  }

  return false;
}

}  // namespace

bool FilterOp::operator()(const fbl::String& test_case, const fbl::String& test) const {
  fbl::String full_test_name = fbl::StringPrintf("%s.%s", test_case.c_str(), test.c_str());
  if (!run_disabled) {
    cpp17::string_view test_case_view(test_case.c_str(), test_case.size());
    cpp17::string_view test_view(test.c_str(), test.size());
    if (test_case_view.find(kDisabledTestPrefix) == 0 || test_view.find(kDisabledTestPrefix) == 0) {
      return false;
    }
  }

  const char* p = pattern.c_str();
  const char* d = strchr(p, '-');
  std::string_view positive, negative;

  // No negative string.
  if (d == nullptr) {
    positive = std::string_view(p, pattern.size());
  } else {
    size_t delta = d - p;
    // No positive pattern.
    // E.g. ":-"
    if (delta == 1) {
      delta--;
    }
    positive = std::string_view(p, delta);
    negative = std::string_view(d + 1, pattern.size() - delta - 1);
  }
  return (positive.empty() || MatchPatterns(positive, full_test_name)) &&
         (negative.empty() || !MatchPatterns(negative, full_test_name));
}

}  // namespace zxtest