// Package outbox 演示在业务事务中使用公共 MySQL Outbox 适配包。
package outbox

import (
	"context"
	"database/sql"
	_ "embed"
	"strings"
	"unicode"
	"unicode/utf8"

	adapter "git.yuntuo.hk/k2safe/orbit/adapters/outbox/mysql"
	orbit "git.yuntuo.hk/k2safe/orbit/sdk/go"
)

//go:embed schema.sql
var schema string
var (
	ErrInvalid           = adapter.ErrInvalid
	ErrStorage           = adapter.ErrStorage
	ErrConflict          = adapter.ErrConflict
	ErrCommitUnconfirmed = adapter.ErrCommitUnconfirmed
	ErrIdle              = adapter.ErrIdle
)

// Store 仅补充示例业务事务；发送、查询、租约由公共包负责。
type Store struct {
	*adapter.Store
	db        *sql.DB
	namespace string
}

var Open = adapter.Open

func Init(ctx context.Context, db *sql.DB) error {
	if err := adapter.Init(ctx, db); err != nil {
		return err
	}
	if _, err := db.ExecContext(ctx, schema); err != nil {
		return ErrStorage
	}
	return nil
}
func New(db *sql.DB, namespace, queue string) (*Store, error) {
	s, err := adapter.New(db, namespace, queue, adapter.Options{OnAccepted: accepted})
	if err != nil {
		return nil, err
	}
	return &Store{s, db, namespace}, nil
}
func accepted(ctx context.Context, tx *sql.Tx, r adapter.Record, receipt orbit.SubmitTaskResult) error {
	var existing *string
	if err := tx.QueryRowContext(ctx, `SELECT task_id FROM sender_jobs WHERE namespace_id=? AND operation_id=? FOR UPDATE`, r.NamespaceID, r.OperationID).Scan(&existing); err != nil {
		return ErrStorage
	}
	if existing != nil && *existing != receipt.Task.ID {
		return ErrConflict
	}
	_, err := tx.ExecContext(ctx, `UPDATE sender_jobs SET task_id=?,updated_at=UTC_TIMESTAMP(6) WHERE namespace_id=? AND operation_id=?`, receipt.Task.ID, r.NamespaceID, r.OperationID)
	if err != nil {
		return ErrStorage
	}
	return nil
}
func (s *Store) Enqueue(ctx context.Context, id, source string, in orbit.SubmitTaskRequest) (bool, error) {
	if !utf8.ValidString(source) || strings.TrimSpace(source) == "" || utf8.RuneCountInString(source) > 512 || strings.ContainsFunc(source, unicode.IsControl) {
		return false, ErrInvalid
	}
	tx, err := s.db.BeginTx(ctx, &sql.TxOptions{Isolation: sql.LevelReadCommitted})
	if err != nil {
		return false, ErrStorage
	}
	defer tx.Rollback()
	duplicate, err := s.Store.EnqueueTx(ctx, tx, id, in)
	if err != nil {
		return false, err
	}
	if duplicate {
		var saved string
		if err = tx.QueryRowContext(ctx, `SELECT source_ref FROM sender_jobs WHERE namespace_id=? AND operation_id=? FOR UPDATE`, s.namespace, id).Scan(&saved); err != nil {
			return false, ErrStorage
		}
		if saved != source {
			return false, ErrConflict
		}
	} else {
		if _, err = tx.ExecContext(ctx, `INSERT INTO sender_jobs(namespace_id,operation_id,source_ref,created_at,updated_at) VALUES(?,?,?,UTC_TIMESTAMP(6),UTC_TIMESTAMP(6))`, s.namespace, id, source); err != nil {
			return false, ErrStorage
		}
	}
	if tx.Commit() != nil {
		return false, ErrCommitUnconfirmed
	}
	return duplicate, nil
}