// Copyright 2016 The Xorm Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package xorm

import "database/sql"

// BeginOpts begins a transaction for this session with the specified opts.
func (session *Session) BeginOpts(opts *sql.TxOptions) error {
	if session.IsInTx() {
		return nil
	}

	tx, err := session.DB().BeginTx(session.ctx, opts)
	if err != nil {
		return err
	}
	session.isAutoCommit = false
	session.isCommitedOrRollbacked = false
	session.tx = tx

	session.saveLastSQL("BEGIN TRANSACTION")
	return nil
}

// Begin a transaction with the default transactions options.
func (session *Session) Begin() error {
	return session.BeginOpts(nil)
}

// Rollback When using transaction, you can rollback if any error
func (session *Session) Rollback() error {
	if !session.isAutoCommit && !session.isCommitedOrRollbacked {
		session.saveLastSQL("ROLL BACK")
		session.isCommitedOrRollbacked = true
		session.isAutoCommit = true

		return session.tx.Rollback()
	}
	return nil
}

// Commit When using transaction, Commit will commit all operations.
func (session *Session) Commit() error {
	if !session.isAutoCommit && !session.isCommitedOrRollbacked {
		session.saveLastSQL("COMMIT")
		session.isCommitedOrRollbacked = true
		session.isAutoCommit = true

		if err := session.tx.Commit(); err != nil {
			return err
		}

		// handle processors after tx committed
		closureCallFunc := func(closuresPtr *[]func(any), bean any) {
			if closuresPtr != nil {
				for _, closure := range *closuresPtr {
					closure(bean)
				}
			}
		}

		for bean, closuresPtr := range session.afterInsertBeans {
			closureCallFunc(closuresPtr, bean)

			if processor, ok := bean.(AfterInsertProcessor); ok {
				processor.AfterInsert()
			}
		}
		for bean, closuresPtr := range session.afterUpdateBeans {
			closureCallFunc(closuresPtr, bean)

			if processor, ok := bean.(AfterUpdateProcessor); ok {
				processor.AfterUpdate()
			}
		}
		for bean, closuresPtr := range session.afterDeleteBeans {
			closureCallFunc(closuresPtr, bean)

			if processor, ok := bean.(AfterDeleteProcessor); ok {
				processor.AfterDelete()
			}
		}
		cleanUpFunc := func(slices *map[any]*[]func(any)) {
			if len(*slices) > 0 {
				*slices = make(map[any]*[]func(any))
			}
		}
		cleanUpFunc(&session.afterInsertBeans)
		cleanUpFunc(&session.afterUpdateBeans)
		cleanUpFunc(&session.afterDeleteBeans)
	}
	return nil
}

// IsInTx returns if the current session is inside a transaction.
func (session *Session) IsInTx() bool {
	return !session.isAutoCommit
}
