// Copyright 2022 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,
// See the License for the specific language governing permissions and
// limitations under the License.

// Package config is the configuration definitions used by the simulator.
package config

import (
	"strconv"
	"strings"

	"github.com/pingcap/tidb/pkg/util/dbutil"
)

// TableConfig is the sub config for describing a simulating table in the data source.
type TableConfig struct {
	TableID              string              `yaml:"id"`
	DatabaseName         string              `yaml:"db"`
	TableName            string              `yaml:"table"`
	Columns              []*ColumnDefinition `yaml:"columns"`
	UniqueKeyColumnNames []string            `yaml:"unique_keys"`
}

// ColumnDefinition is the sub config for describing a column in a simulating table.
type ColumnDefinition struct {
	ColumnName string `yaml:"name"`
	DataType   string `yaml:"type"`
	DataLen    int    `yaml:"length"`
}

func (t *TableConfig) GenCreateTable() string {
	var buf strings.Builder
	buf.WriteString("CREATE TABLE ")
	buf.WriteString(dbutil.TableName(t.DatabaseName, t.TableName))
	buf.WriteByte('(')
	for i, col := range t.Columns {
		if i != 0 {
			buf.WriteByte(',')
		}
		buf.WriteString(dbutil.ColumnName(col.ColumnName))
		buf.WriteByte(' ')
		buf.WriteString(col.DataType)
		if col.DataLen > 0 {
			buf.WriteByte('(')
			buf.WriteString(strconv.Itoa(col.DataLen))
			buf.WriteByte(')')
		}
	}
	if len(t.UniqueKeyColumnNames) > 0 {
		buf.WriteString(",UNIQUE KEY ")
		buf.WriteString(dbutil.ColumnName(strings.Join(t.UniqueKeyColumnNames, "_")))
		buf.WriteByte('(')
		for i, ukColName := range t.UniqueKeyColumnNames {
			if i != 0 {
				buf.WriteString(",")
			}
			buf.WriteString(dbutil.ColumnName(ukColName))
		}
		buf.WriteByte(')')
	}
	buf.WriteByte(')')
	return buf.String()
}