#include <gtest/gtest.h>
#include <gmock/gmock-matchers.h>

#include "ResultSourceMapping.h"


namespace {

constexpr Oid tableA = 1001;
constexpr Oid tableB = 1002;

ResultColumnSource src(Oid table, int attnum)
{
	ResultColumnSource s;
	s.tableOid = table;
	s.attnum = attnum;
	return s;
}

ResultColumnSource expression()
{
	return ResultColumnSource{};
}

TablePrimaryKey pk(Oid table, std::vector<int> attnums)
{
	TablePrimaryKey key;
	key.tableOid = table;
	key.attnums = std::move(attnums);
	return key;
}

}


TEST(ResultSourceMappingTest, single_table_with_pk_all_columns_editable)
{
	ResultSourceMapping m({src(tableA, 1), src(tableA, 2), src(tableA, 3)}, {pk(tableA, {1})});

	EXPECT_EQ(m.columnCount(), 3);
	EXPECT_TRUE(m.isEditable(0));
	EXPECT_TRUE(m.isEditable(1));
	EXPECT_TRUE(m.isEditable(2));
	EXPECT_EQ(m.tableOid(1), tableA);
	EXPECT_EQ(m.attnum(2), 3);
	EXPECT_THAT(m.primaryKeyColumns(tableA), ::testing::ElementsAre(0));
}

TEST(ResultSourceMappingTest, composite_pk_maps_key_columns_in_key_order)
{
	ResultSourceMapping m({src(tableA, 3), src(tableA, 1), src(tableA, 2)}, {pk(tableA, {1, 2})});

	EXPECT_TRUE(m.isEditable(0));
	EXPECT_THAT(m.primaryKeyColumns(tableA), ::testing::ElementsAre(1, 2));
}

TEST(ResultSourceMappingTest, join_with_both_pks_both_tables_editable)
{
	ResultSourceMapping m({src(tableA, 1), src(tableA, 2), src(tableB, 1), src(tableB, 2)},
		{pk(tableA, {1}), pk(tableB, {1})});

	for (int col = 0; col < m.columnCount(); ++col) {
		EXPECT_TRUE(m.isEditable(col)) << "column " << col;
	}
	EXPECT_THAT(m.primaryKeyColumns(tableA), ::testing::ElementsAre(0));
	EXPECT_THAT(m.primaryKeyColumns(tableB), ::testing::ElementsAre(2));
}

TEST(ResultSourceMappingTest, join_where_only_one_table_has_pk_in_result)
{
	ResultSourceMapping m({src(tableA, 1), src(tableA, 2), src(tableB, 2)},
		{pk(tableA, {1}), pk(tableB, {1})});

	EXPECT_TRUE(m.isEditable(0));
	EXPECT_TRUE(m.isEditable(1));
	EXPECT_FALSE(m.isEditable(2));
	EXPECT_TRUE(m.primaryKeyColumns(tableB).empty());
}

TEST(ResultSourceMappingTest, pk_missing_from_result_is_read_only)
{
	ResultSourceMapping m({src(tableA, 2), src(tableA, 3)}, {pk(tableA, {1})});

	EXPECT_FALSE(m.isEditable(0));
	EXPECT_FALSE(m.isEditable(1));
	EXPECT_TRUE(m.primaryKeyColumns(tableA).empty());
}

TEST(ResultSourceMappingTest, composite_pk_partially_present_is_read_only)
{
	ResultSourceMapping m({src(tableA, 1), src(tableA, 3)}, {pk(tableA, {1, 2})});

	EXPECT_FALSE(m.isEditable(0));
	EXPECT_FALSE(m.isEditable(1));
}

TEST(ResultSourceMappingTest, table_without_pk_is_read_only)
{
	ResultSourceMapping m({src(tableA, 1), src(tableA, 2)}, {});

	EXPECT_FALSE(m.isEditable(0));
	EXPECT_FALSE(m.isEditable(1));
}

TEST(ResultSourceMappingTest, expression_column_is_read_only)
{
	ResultSourceMapping m({src(tableA, 1), expression(), src(tableA, 2)}, {pk(tableA, {1})});

	EXPECT_TRUE(m.isEditable(0));
	EXPECT_FALSE(m.isEditable(1));
	EXPECT_EQ(m.tableOid(1), InvalidOid);
	EXPECT_EQ(m.attnum(1), 0);
	EXPECT_TRUE(m.isEditable(2));
}

TEST(ResultSourceMappingTest, system_column_is_read_only)
{
	ResultSourceMapping m({src(tableA, 1), src(tableA, -2)}, {pk(tableA, {1})});

	EXPECT_TRUE(m.isEditable(0));
	EXPECT_FALSE(m.isEditable(1));
}

TEST(ResultSourceMappingTest, duplicate_pk_column_still_editable)
{
	ResultSourceMapping m({src(tableA, 1), src(tableA, 1), src(tableA, 2)}, {pk(tableA, {1})});

	EXPECT_TRUE(m.isEditable(0));
	EXPECT_TRUE(m.isEditable(1));
	EXPECT_TRUE(m.isEditable(2));
	EXPECT_THAT(m.primaryKeyColumns(tableA), ::testing::ElementsAre(0));
}

TEST(ResultSourceMappingTest, same_non_pk_column_twice_makes_table_read_only)
{
	ResultSourceMapping m({src(tableA, 1), src(tableA, 2), src(tableA, 2)}, {pk(tableA, {1})});

	EXPECT_FALSE(m.isEditable(0));
	EXPECT_FALSE(m.isEditable(1));
	EXPECT_FALSE(m.isEditable(2));
	EXPECT_TRUE(m.primaryKeyColumns(tableA).empty());
}

TEST(ResultSourceMappingTest, self_join_with_aliased_non_pk_columns_is_read_only)
{
	ResultSourceMapping m({src(tableA, 1), src(tableA, 1), src(tableA, 2), src(tableA, 2)}, {pk(tableA, {1})});

	EXPECT_FALSE(m.isEditable(0));
	EXPECT_FALSE(m.isEditable(2));
}

TEST(ResultSourceMappingTest, out_of_range_column_throws)
{
	ResultSourceMapping m({src(tableA, 1)}, {pk(tableA, {1})});

	EXPECT_THROW(m.isEditable(1), std::range_error);
	EXPECT_THROW(m.isEditable(-1), std::range_error);
	EXPECT_THROW(m.tableOid(1), std::range_error);
	EXPECT_THROW(m.attnum(-1), std::range_error);
}

TEST(ResultSourceMappingTest, empty_result_has_no_columns)
{
	ResultSourceMapping m({}, {});

	EXPECT_EQ(m.columnCount(), 0);
	EXPECT_TRUE(m.primaryKeyColumns(tableA).empty());
}