#include <sstream>
#include <cstdint>

#include "gtest/gtest.h"

#include "libimp/result.h"
#include "libimp/fmt.h"

TEST(result, ok) {
  imp::result_code ret;
  EXPECT_FALSE(ret);
  EXPECT_FALSE(ret.ok());
  EXPECT_EQ(ret.value(), 0);

  ret = {0, true};
  EXPECT_TRUE(ret);
  EXPECT_TRUE(ret.ok());
  EXPECT_EQ(ret.value(), 0);

  ret = {0, false};
  EXPECT_FALSE(ret);
  EXPECT_FALSE(ret.ok());
  EXPECT_EQ(ret.value(), 0);

  ret = {0};
  EXPECT_TRUE(ret);
  EXPECT_TRUE(ret.ok());
  EXPECT_EQ(ret.value(), 0);

  ret = {1234, false};
  EXPECT_FALSE(ret);
  EXPECT_FALSE(ret.ok());
  EXPECT_EQ(*ret, 1234);

  ret = imp::result_code(1234, true);
  EXPECT_TRUE(ret);
  EXPECT_TRUE(ret.ok());
  EXPECT_EQ(ret.value(), 1234);

  ret = {0, false};
  EXPECT_FALSE(ret);
  EXPECT_FALSE(ret.ok());
  EXPECT_EQ(ret.value(), 0);

  ret = {4321, true};
  EXPECT_TRUE(ret);
  EXPECT_TRUE(ret.ok());
  EXPECT_EQ(ret.value(), 4321);

  imp::result<void> r1;
  EXPECT_FALSE(r1);
  r1 = std::error_code{};
  EXPECT_TRUE(r1);
  r1 = {};
  EXPECT_FALSE(r1);
  r1 = std::error_code{9999, std::generic_category()};
  EXPECT_FALSE(r1);
  EXPECT_EQ(r1.error().value(), 9999);

  imp::result<int *> r2 {nullptr, std::error_code{4321, std::generic_category()}};
  EXPECT_NE(r2, nullptr); // imp::result<int *>{nullptr}
  EXPECT_EQ(*r2, nullptr);
  EXPECT_FALSE(r2);
}

TEST(result, compare) {
  imp::result_code r1, r2;
  EXPECT_EQ(r1, r2);

  imp::result_code r3(0, true);
  EXPECT_NE(r1, r3);

  imp::result_code r4(222222, true);
  EXPECT_NE(r3, r4);

  imp::result_code r5(222222, false);
  EXPECT_NE(r4, r5);
  r3 = r5;
  EXPECT_EQ(r3, r5);
}

TEST(result, fmt) {
  {
    imp::result_code r1;
    EXPECT_EQ(imp::fmt(r1), "fail, value = 0");
    imp::result_code r2(65537, true);
    EXPECT_EQ(imp::fmt(r2), "succ, value = 65537");
    imp::result_code r3(0);
    EXPECT_EQ(imp::fmt(r3), "succ, value = 0");
  }
  {
    imp::result<int> r0;
    EXPECT_EQ(imp::fmt(r0), imp::fmt(imp::result_code()));
    imp::result<int> r1 {-123, false};
    EXPECT_EQ(imp::fmt(r1), imp::fmt("fail, value = ", -123));

    imp::result<void *> r2 {&r1};
    EXPECT_EQ(imp::fmt(r2), imp::fmt("succ, value = ", (void *)&r1));

    int aaa {};
    imp::result<int *> r3 {&aaa};
    EXPECT_EQ(imp::fmt(r3), imp::fmt("succ, value = ", (void *)&aaa));
    imp::result<int *> r4 {nullptr};
    EXPECT_EQ(imp::fmt(r4), imp::fmt("fail, value = ", nullptr, ", error = [generic: 0, \"failure\"]"));
    r4 = {nullptr, std::error_code{1234, std::generic_category()}};
    EXPECT_EQ(imp::fmt(r4), imp::fmt("fail, value = ", nullptr, ", error = [generic: 1234, \"failure\"]"));
    imp::result<int *> r5;
    EXPECT_EQ(imp::fmt(r5), "fail, value = null, error = [generic: 0, \"failure\"]");
  }
  {
    imp::result<std::int64_t> r1 {-123};
    EXPECT_EQ(imp::fmt(r1), imp::fmt("succ, value = ", -123));
  }
  {
    imp::result<void> r1;
    EXPECT_EQ(imp::fmt(r1), "fail, error = [generic: 0, \"failure\"]");
    r1 = std::error_code{};
    EXPECT_TRUE(r1);
    EXPECT_EQ(imp::fmt(r1), "succ, error = [generic: 0, \"success\"]");
  }
}