// Copyright © 2016 SurrealDB Ltd.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance wdbh 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 db

import (
	"context"

	"golang.org/x/crypto/bcrypt"

	"github.com/surrealdb/surrealdb/cnf"
	"github.com/surrealdb/surrealdb/sql"
	"github.com/surrealdb/surrealdb/util/keys"
	"github.com/surrealdb/surrealdb/util/rand"
)

func (e *executor) executeDefineNamespace(ctx context.Context, ast *sql.DefineNamespaceStatement) (out []interface{}, err error) {

	if err := e.access(ctx, cnf.AuthKV); err != nil {
		return nil, err
	}

	// Save the namespace definition
	nkey := &keys.NS{KV: KV, NS: ast.Name.VA}
	_, err = e.tx.Put(ctx, 0, nkey.Encode(), ast.Encode())

	return

}

func (e *executor) executeDefineDatabase(ctx context.Context, ast *sql.DefineDatabaseStatement) (out []interface{}, err error) {

	if err := e.access(ctx, cnf.AuthNS); err != nil {
		return nil, err
	}

	e.tx.AddNS(ctx, e.ns)

	// Save the database definition
	dkey := &keys.DB{KV: KV, NS: e.ns, DB: ast.Name.VA}
	_, err = e.tx.Put(ctx, 0, dkey.Encode(), ast.Encode())

	return

}

func (e *executor) executeDefineLogin(ctx context.Context, ast *sql.DefineLoginStatement) (out []interface{}, err error) {

	ast.Code = rand.New(128)

	switch len(ast.Hash) {
	default:
		ast.Pass = ast.Hash
	case 0:
		ast.Pass, _ = bcrypt.GenerateFromPassword(ast.Pass, bcrypt.DefaultCost)
	}

	switch ast.Kind {
	case sql.NAMESPACE:

		if err := e.access(ctx, cnf.AuthNS); err != nil {
			return nil, err
		}

		e.tx.AddNS(ctx, e.ns)

		// Save the login definition
		ukey := &keys.NU{KV: KV, NS: e.ns, US: ast.User.VA}
		_, err = e.tx.Put(ctx, 0, ukey.Encode(), ast.Encode())

	case sql.DATABASE:

		if err := e.access(ctx, cnf.AuthDB); err != nil {
			return nil, err
		}

		e.tx.AddDB(ctx, e.ns, e.db)

		// Save the login definition
		ukey := &keys.DU{KV: KV, NS: e.ns, DB: e.db, US: ast.User.VA}
		_, err = e.tx.Put(ctx, 0, ukey.Encode(), ast.Encode())

	}

	return

}

func (e *executor) executeDefineToken(ctx context.Context, ast *sql.DefineTokenStatement) (out []interface{}, err error) {

	switch ast.Kind {
	case sql.NAMESPACE:

		if err := e.access(ctx, cnf.AuthNS); err != nil {
			return nil, err
		}

		e.tx.AddNS(ctx, e.ns)

		// Save the token definition
		tkey := &keys.NT{KV: KV, NS: e.ns, TK: ast.Name.VA}
		_, err = e.tx.Put(ctx, 0, tkey.Encode(), ast.Encode())

	case sql.DATABASE:

		if err := e.access(ctx, cnf.AuthDB); err != nil {
			return nil, err
		}

		e.tx.AddDB(ctx, e.ns, e.db)

		// Save the token definition
		tkey := &keys.DT{KV: KV, NS: e.ns, DB: e.db, TK: ast.Name.VA}
		_, err = e.tx.Put(ctx, 0, tkey.Encode(), ast.Encode())

	case sql.SCOPE:

		if err := e.access(ctx, cnf.AuthDB); err != nil {
			return nil, err
		}

		e.tx.AddDB(ctx, e.ns, e.db)

		// Save the token definition
		tkey := &keys.ST{KV: KV, NS: e.ns, DB: e.db, SC: ast.What.VA, TK: ast.Name.VA}
		_, err = e.tx.Put(ctx, 0, tkey.Encode(), ast.Encode())

	}

	return

}

func (e *executor) executeDefineScope(ctx context.Context, ast *sql.DefineScopeStatement) (out []interface{}, err error) {

	if err := e.access(ctx, cnf.AuthDB); err != nil {
		return nil, err
	}

	ast.Code = rand.New(128)

	e.tx.AddDB(ctx, e.ns, e.db)

	// Remove the scope definition
	skey := &keys.SC{KV: KV, NS: e.ns, DB: e.db, SC: ast.Name.VA}
	_, err = e.tx.Put(ctx, 0, skey.Encode(), ast.Encode())

	return

}

func (e *executor) executeDefineEvent(ctx context.Context, ast *sql.DefineEventStatement) (out []interface{}, err error) {

	if err := e.access(ctx, cnf.AuthDB); err != nil {
		return nil, err
	}

	for _, TB := range ast.What {

		e.tx.AddTB(ctx, e.ns, e.db, TB.TB)

		// Remove the event definition
		ekey := &keys.EV{KV: KV, NS: e.ns, DB: e.db, TB: TB.TB, EV: ast.Name.VA}
		if _, err = e.tx.Put(ctx, 0, ekey.Encode(), ast.Encode()); err != nil {
			return nil, err
		}

	}

	return

}

func (e *executor) executeDefineField(ctx context.Context, ast *sql.DefineFieldStatement) (out []interface{}, err error) {

	if err := e.access(ctx, cnf.AuthDB); err != nil {
		return nil, err
	}

	for _, TB := range ast.What {

		e.tx.AddTB(ctx, e.ns, e.db, TB.TB)

		// Save the field definition
		fkey := &keys.FD{KV: KV, NS: e.ns, DB: e.db, TB: TB.TB, FD: ast.Name.VA}
		if _, err = e.tx.Put(ctx, 0, fkey.Encode(), ast.Encode()); err != nil {
			return nil, err
		}

	}

	return

}

func (e *executor) executeDefineIndex(ctx context.Context, ast *sql.DefineIndexStatement) (out []interface{}, err error) {

	if err := e.access(ctx, cnf.AuthDB); err != nil {
		return nil, err
	}

	for _, TB := range ast.What {

		e.tx.AddTB(ctx, e.ns, e.db, TB.TB)

		// Save the index definition
		ikey := &keys.IX{KV: KV, NS: e.ns, DB: e.db, TB: TB.TB, IX: ast.Name.VA}
		if _, err = e.tx.Put(ctx, 0, ikey.Encode(), ast.Encode()); err != nil {
			return nil, err
		}

		// Remove the index resource data
		dkey := &keys.Index{KV: KV, NS: e.ns, DB: e.db, TB: TB.TB, IX: ast.Name.VA, FD: keys.Ignore}
		if _, err = e.tx.ClrP(ctx, dkey.Encode(), 0); err != nil {
			return nil, err
		}

		// Process the index resource data
		uctx := context.WithValue(ctx, ctxKeyForce, true)
		ustm := &sql.UpdateStatement{What: []sql.Expr{TB}}
		if _, err = e.executeUpdate(uctx, ustm); err != nil {
			return nil, err
		}

	}

	return

}

func (e *executor) executeDefineTable(ctx context.Context, ast *sql.DefineTableStatement) (out []interface{}, err error) {

	if err := e.access(ctx, cnf.AuthDB); err != nil {
		return nil, err
	}

	e.tx.AddDB(ctx, e.ns, e.db)

	for _, TB := range ast.What {

		ast.Name = sql.NewIdent(TB.TB)

		// Save the table definition
		tkey := &keys.TB{KV: KV, NS: e.ns, DB: e.db, TB: TB.TB}
		if _, err = e.tx.Put(ctx, 0, tkey.Encode(), ast.Encode()); err != nil {
			return nil, err
		}

		if ast.Lock {

			// Remove the table resource data
			dkey := &keys.Table{KV: KV, NS: e.ns, DB: e.db, TB: TB.TB}
			if _, err = e.tx.ClrP(ctx, dkey.Encode(), 0); err != nil {
				return nil, err
			}

			for _, FT := range ast.From {

				// Save the foreign table definition
				tkey := &keys.FT{KV: KV, NS: e.ns, DB: e.db, TB: FT.TB, FT: TB.TB}
				if _, err = e.tx.Put(ctx, 0, tkey.Encode(), ast.Encode()); err != nil {
					return nil, err
				}

				// Process the table resource data
				uctx := context.WithValue(ctx, ctxKeyForce, true)
				ustm := &sql.UpdateStatement{What: []sql.Expr{FT}}
				if _, err = e.executeUpdate(uctx, ustm); err != nil {
					return nil, err
				}

			}

		}

	}

	return

}