// Copyright 2017 PingCAP, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package executor_test

import (
	"fmt"
	"strings"
	"testing"

	"github.com/pingcap/tidb/executor"
	"github.com/pingcap/tidb/parser/mysql"
	"github.com/pingcap/tidb/parser/terror"
	"github.com/pingcap/tidb/testkit"
	"github.com/stretchr/testify/require"
)

func TestRevokeGlobal(t *testing.T) {
	store := testkit.CreateMockStore(t)
	tk := testkit.NewTestKit(t, store)

	_, err := tk.Exec(`REVOKE ALL PRIVILEGES ON *.* FROM 'nonexistuser'@'host'`)
	require.Error(t, err)

	// Create a new user.
	createUserSQL := `CREATE USER 'testGlobalRevoke'@'localhost' IDENTIFIED BY '123';`
	tk.MustExec(createUserSQL)
	grantPrivSQL := `GRANT ALL PRIVILEGES ON *.* to 'testGlobalRevoke'@'localhost';`
	tk.MustExec(grantPrivSQL)

	// Make sure all the global privs for new user is "Y".
	for _, v := range mysql.AllDBPrivs {
		sql := fmt.Sprintf(`SELECT %s FROM mysql.User WHERE User="testGlobalRevoke" and host="localhost";`, mysql.Priv2UserCol[v])
		r := tk.MustQuery(sql)
		r.Check(testkit.Rows("Y"))
	}

	// Revoke each priv from the user.
	for _, v := range mysql.AllGlobalPrivs {
		sql := fmt.Sprintf("REVOKE %s ON *.* FROM 'testGlobalRevoke'@'localhost';", mysql.Priv2Str[v])
		tk.MustExec(sql)
		sql = fmt.Sprintf(`SELECT %s FROM mysql.User WHERE User="testGlobalRevoke" and host="localhost"`, mysql.Priv2UserCol[v])
		tk.MustQuery(sql).Check(testkit.Rows("N"))
	}
}

func TestRevokeDBScope(t *testing.T) {
	store := testkit.CreateMockStore(t)
	tk := testkit.NewTestKit(t, store)
	// Create a new user.
	tk.MustExec(`CREATE USER 'testDBRevoke'@'localhost' IDENTIFIED BY '123';`)
	tk.MustExec(`GRANT ALL ON test.* TO 'testDBRevoke'@'localhost';`)

	_, err := tk.Exec(`REVOKE ALL PRIVILEGES ON nonexistdb.* FROM 'testDBRevoke'@'localhost'`)
	require.Error(t, err)

	// Revoke each priv from the user.
	for _, v := range mysql.AllDBPrivs {
		check := fmt.Sprintf(`SELECT %s FROM mysql.DB WHERE User="testDBRevoke" and host="localhost" and db="test"`, mysql.Priv2UserCol[v])
		sql := fmt.Sprintf("REVOKE %s ON test.* FROM 'testDBRevoke'@'localhost';", mysql.Priv2Str[v])

		tk.MustQuery(check).Check(testkit.Rows("Y"))
		tk.MustExec(sql)
		if v == mysql.AllDBPrivs[len(mysql.AllDBPrivs)-1] {
			// When all privileges are set to 'N', then the record should be removed as well.
			// https://github.com/pingcap/tidb/issues/38363
			tk.MustQuery(check).Check(testkit.Rows())
		} else {
			tk.MustQuery(check).Check(testkit.Rows("N"))
		}
	}
}

func TestRevokeTableScope(t *testing.T) {
	store := testkit.CreateMockStore(t)
	tk := testkit.NewTestKit(t, store)
	// Create a new user.
	tk.MustExec(`CREATE USER 'testTblRevoke'@'localhost' IDENTIFIED BY '123';`)
	tk.MustExec(`CREATE TABLE test.test1(c1 int);`)
	tk.MustExec(`GRANT ALL PRIVILEGES ON test.test1 TO 'testTblRevoke'@'localhost';`)

	_, err := tk.Exec(`REVOKE ALL PRIVILEGES ON test.nonexisttable FROM 'testTblRevoke'@'localhost'`)
	require.Error(t, err)

	// Make sure all the table privs for new user is Y.
	res := tk.MustQuery(`SELECT Table_priv FROM mysql.tables_priv WHERE User="testTblRevoke" and host="localhost" and db="test" and Table_name="test1"`)
	res.Check(testkit.Rows("Select,Insert,Update,Delete,Create,Drop,Index,Alter,Create View,Show View,Trigger,References"))

	// Revoke each priv from the user.
	for index, v := range mysql.AllTablePrivs {
		sql := fmt.Sprintf("REVOKE %s ON test.test1 FROM 'testTblRevoke'@'localhost';", mysql.Priv2Str[v])
		tk.MustExec(sql)
		rows := tk.MustQuery(`SELECT Table_priv FROM mysql.tables_priv WHERE User="testTblRevoke" and host="localhost" and db="test" and Table_name="test1";`).Rows()
		if index < len(mysql.AllTablePrivs)-1 {
			require.Len(t, rows, 1)
			row := rows[0]
			require.Len(t, row, 1)
			op := v.SetString()
			found := false
			for _, p := range executor.SetFromString(fmt.Sprintf("%s", row[0])) {
				if op == p {
					found = true
					break
				}
			}
			require.False(t, found, "%s", mysql.Priv2SetStr[v])
		} else {
			//delete row when last prv , updated by issue #38421
			require.Len(t, rows, 0)
		}
	}

	// Revoke all table scope privs.
	tk.MustExec(`GRANT ALL PRIVILEGES ON test.test1 TO 'testTblRevoke'@'localhost';`)
	tk.MustExec("REVOKE ALL ON test.test1 FROM 'testTblRevoke'@'localhost';")
	//delete row when last prv , updated by issue #38421
	rows := tk.MustQuery(`SELECT Table_priv FROM mysql.Tables_priv WHERE User="testTblRevoke" and host="localhost" and db="test" and Table_name="test1"`).Rows()
	require.Len(t, rows, 0)
}

func TestRevokeColumnScope(t *testing.T) {
	store := testkit.CreateMockStore(t)
	tk := testkit.NewTestKit(t, store)
	// Create a new user.
	tk.MustExec(`CREATE USER 'testColRevoke'@'localhost' IDENTIFIED BY '123';`)
	tk.MustExec(`CREATE TABLE test.test3(c1 int, c2 int);`)
	tk.MustQuery(`SELECT * FROM mysql.Columns_priv WHERE User="testColRevoke" and host="localhost" and db="test" and Table_name="test3" and Column_name="c2"`).Check(testkit.Rows())

	// Grant and Revoke each priv on the user.
	for _, v := range mysql.AllColumnPrivs {
		grantSQL := fmt.Sprintf("GRANT %s(c1) ON test.test3 TO 'testColRevoke'@'localhost';", mysql.Priv2Str[v])
		revokeSQL := fmt.Sprintf("REVOKE %s(c1) ON test.test3 FROM 'testColRevoke'@'localhost';", mysql.Priv2Str[v])
		checkSQL := `SELECT Column_priv FROM mysql.Columns_priv WHERE User="testColRevoke" and host="localhost" and db="test" and Table_name="test3" and Column_name="c1"`

		tk.MustExec(grantSQL)
		rows := tk.MustQuery(checkSQL).Rows()
		require.Len(t, rows, 1)
		row := rows[0]
		require.Len(t, row, 1)
		p := fmt.Sprintf("%v", row[0])
		require.Greater(t, strings.Index(p, mysql.Priv2SetStr[v]), -1)

		tk.MustExec(revokeSQL)
		//delete row when last prv , updated by issue #38421
		rows = tk.MustQuery(checkSQL).Rows()
		require.Len(t, rows, 0)
	}

	// Create a new user.
	tk.MustExec("CREATE USER 'testCol1Revoke'@'localhost' IDENTIFIED BY '123';")
	tk.MustExec("USE test;")
	// Grant all column scope privs.
	tk.MustExec("GRANT ALL(c2) ON test3 TO 'testCol1Revoke'@'localhost';")
	// Make sure all the column privs for granted user are in the Column_priv set.
	for _, v := range mysql.AllColumnPrivs {
		rows := tk.MustQuery(`SELECT Column_priv FROM mysql.Columns_priv WHERE User="testCol1Revoke" and host="localhost" and db="test" and Table_name="test3" and Column_name="c2";`).Rows()
		require.Len(t, rows, 1)
		row := rows[0]
		require.Len(t, row, 1)
		p := fmt.Sprintf("%v", row[0])
		require.Greater(t, strings.Index(p, mysql.Priv2SetStr[v]), -1)
	}
	tk.MustExec("REVOKE ALL(c2) ON test3 FROM 'testCol1Revoke'@'localhost'")
	//delete row when last prv , updated by issue #38421
	rows := tk.MustQuery(`SELECT Column_priv FROM mysql.Columns_priv WHERE User="testCol1Revoke" and host="localhost" and db="test" and Table_name="test3"`).Rows()
	require.Len(t, rows, 0)
}

// ref issue #38421
func TestRevokeTableSingle(t *testing.T) {
	store := testkit.CreateMockStore(t)
	tk := testkit.NewTestKit(t, store)
	// Create a new user.
	tk.MustExec(`CREATE USER test;`)
	tk.MustExec(`CREATE TABLE test.test1(c1 int);`)
	tk.MustExec(`GRANT SELECT  ON test.test1 TO test;`)

	tk.MustExec(`REVOKE SELECT  ON test.test1 from test;`)

	rows := tk.MustQuery(`SELECT Column_priv FROM mysql.tables_priv WHERE User="test" `).Rows()
	require.Len(t, rows, 0)
}

// ref issue #38421(column fix)
func TestRevokeTableSingleColumn(t *testing.T) {
	store := testkit.CreateMockStore(t)
	tk := testkit.NewTestKit(t, store)
	// Create a new user.
	tk.MustExec(`CREATE USER test;`)
	tk.MustExec(`GRANT SELECT(Host) ON mysql.db TO test`)
	tk.MustExec(`GRANT SELECT(DB) ON mysql.db TO test`)
	tk.MustExec(`REVOKE SELECT(Host) ON mysql.db FROM test`)

	rows := tk.MustQuery(`SELECT Column_priv FROM mysql.columns_priv WHERE User="test" and Column_name ='Host' `).Rows()
	require.Len(t, rows, 0)
	rows = tk.MustQuery(`SELECT Column_priv FROM mysql.columns_priv WHERE User="test" and Column_name ='DB' `).Rows()
	require.Len(t, rows, 1)
}

func TestRevokeDynamicPrivs(t *testing.T) {
	store := testkit.CreateMockStore(t)
	tk := testkit.NewTestKit(t, store)

	tk.MustExec("DROP USER if exists dyn")
	tk.MustExec("create user dyn")

	tk.MustExec("GRANT BACKUP_Admin ON *.* TO dyn") // grant one priv
	tk.MustQuery("SELECT * FROM mysql.global_grants WHERE `Host` = '%' AND `User` = 'dyn' ORDER BY user,host,priv,with_grant_option").Check(testkit.Rows("dyn % BACKUP_ADMIN N"))

	// try revoking only on test.* - should fail:
	_, err := tk.Exec("REVOKE BACKUP_Admin,system_variables_admin ON test.* FROM dyn")
	require.True(t, terror.ErrorEqual(err, executor.ErrIllegalPrivilegeLevel))

	// privs should still be intact:
	tk.MustQuery("SELECT * FROM mysql.global_grants WHERE `Host` = '%' AND `User` = 'dyn' ORDER BY user,host,priv,with_grant_option").Check(testkit.Rows("dyn % BACKUP_ADMIN N"))
	// with correct usage, the privilege is revoked
	tk.MustExec("REVOKE BACKUP_Admin ON *.* FROM dyn")
	tk.MustQuery("SELECT * FROM mysql.global_grants WHERE `Host` = '%' AND `User` = 'dyn' ORDER BY user,host,priv,with_grant_option").Check(testkit.Rows())

	// Revoke bogus is a warning in MySQL
	tk.MustExec("REVOKE bogus ON *.* FROM dyn")
	tk.MustQuery("SHOW WARNINGS").Check(testkit.Rows("Warning 3929 Dynamic privilege 'BOGUS' is not registered with the server."))

	// grant and revoke two dynamic privileges at once.
	tk.MustExec("GRANT BACKUP_ADMIN, SYSTEM_VARIABLES_ADMIN ON *.* TO dyn")
	tk.MustQuery("SELECT * FROM mysql.global_grants WHERE `Host` = '%' AND `User` = 'dyn' ORDER BY user,host,priv,with_grant_option").Check(testkit.Rows("dyn % BACKUP_ADMIN N", "dyn % SYSTEM_VARIABLES_ADMIN N"))
	tk.MustExec("REVOKE BACKUP_ADMIN, SYSTEM_VARIABLES_ADMIN ON *.* FROM dyn")
	tk.MustQuery("SELECT * FROM mysql.global_grants WHERE `Host` = '%' AND `User` = 'dyn' ORDER BY user,host,priv,with_grant_option").Check(testkit.Rows())

	// revoke a combination of dynamic + non-dynamic
	tk.MustExec("GRANT BACKUP_ADMIN, SYSTEM_VARIABLES_ADMIN, SELECT, INSERT ON *.* TO dyn")
	tk.MustExec("REVOKE BACKUP_ADMIN, SYSTEM_VARIABLES_ADMIN, SELECT, INSERT ON *.* FROM dyn")
	tk.MustQuery("SELECT * FROM mysql.global_grants WHERE `Host` = '%' AND `User` = 'dyn' ORDER BY user,host,priv,with_grant_option").Check(testkit.Rows())

	// revoke grant option from privileges
	tk.MustExec("GRANT BACKUP_ADMIN, SYSTEM_VARIABLES_ADMIN, SELECT ON *.* TO dyn WITH GRANT OPTION")
	tk.MustExec("REVOKE BACKUP_ADMIN, SELECT, GRANT OPTION ON *.* FROM dyn")
	tk.MustQuery("SELECT * FROM mysql.global_grants WHERE `Host` = '%' AND `User` = 'dyn' ORDER BY user,host,priv,with_grant_option").Check(testkit.Rows("dyn % SYSTEM_VARIABLES_ADMIN Y"))
}

func TestRevokeOnNonExistTable(t *testing.T) {
	// issue #28533
	store := testkit.CreateMockStore(t)
	tk := testkit.NewTestKit(t, store)

	tk.MustExec("CREATE DATABASE d1;")
	defer tk.MustExec("DROP DATABASE IF EXISTS d1;")
	tk.MustExec("USE d1;")
	tk.MustExec("CREATE TABLE t1 (a int)")
	defer tk.MustExec("DROP TABLE IF EXISTS t1")
	tk.MustExec("CREATE USER issue28533")
	defer tk.MustExec("DROP USER issue28533")

	// GRANT ON existent table success
	tk.MustExec("GRANT ALTER ON d1.t1 TO issue28533;")
	// GRANT ON non-existent table success
	tk.MustExec("GRANT INSERT, CREATE ON d1.t2 TO issue28533;")

	// REVOKE ON non-existent table success
	tk.MustExec("DROP TABLE t1;")
	tk.MustExec("REVOKE ALTER ON d1.t1 FROM issue28533;")
}