// Package sql2go...
//
// Description : sql2go...
//
// Author : go_developer@163.com<白茶清欢>
//
// Date : 2021-10-25 4:49 下午
package sql2go

import (
	"errors"
	wrapperType "git.zhangdeman.cn/zhangdeman/wrapper"
	"strings"

	"github.com/xwb1989/sqlparser"
)

const (
	// CreateSQLColumnTPL 每个字段的模版
	CreateSQLColumnTPL = "    {FIELD} {TYPE} `json:\"{JSON_TAG}\" gorm:\"column:{COLUMN};default:{DEFAULT_VALUE};{NOT_NULL}\"` // {COMMENT}"
	// TableColumnTpl 每个字段的模版
	TableColumnTpl = "    {FIELD} string `json:\"{JSON_TAG}\"`"
	// TableColumnDescTpl 字段描述
	TableColumnDescTpl = "    {FIELD}: \"{JSON_TAG}\""
	// TableColumnCommentTpl 字段描述
	TableColumnCommentTpl = "    \"{JSON_TAG}\": \"{FIELD_COMMENT}\""
)

// BasicTableInfo ...
//
// Author : go_developer@163.com<白茶清欢>
//
// Date : 11:47 上午 2021/11/17
type BasicTableInfo struct {
	TableName         string `json:"table_name"`          // 表名称
	ModelStructName   string `json:"model_struct_name"`   // 生成的结构体名称
	ModelStruct       string `json:"model_struct"`        // 生成的结构体内容
	PrimaryField      string `json:"primary_field"`       // 主键字段
	PrimaryFieldType  string `json:"primary_field_type"`  // 主键字段类型
	ColumnDefined     string `json:"column_defined"`      // 字段定义
	ColumnDescDefined string `json:"column_desc_defined"` // 字段描述定义
}

// ParseCreateTableSql 解析建表sql
//
// Author : go_developer@163.com<白茶清欢>
//
// Date : 4:49 下午 2021/10/25
func ParseCreateTableSql(sql string) (*BasicTableInfo, error) {
	var (
		stmt  sqlparser.Statement
		err   error
		basic *BasicTableInfo
	)
	basic = &BasicTableInfo{
		TableName:         "",
		ModelStructName:   "",
		ModelStruct:       "",
		PrimaryField:      "ID",
		PrimaryFieldType:  "",
		ColumnDefined:     "",
		ColumnDescDefined: "",
	}
	sql = strings.ReplaceAll(strings.ReplaceAll(sql, "CURRENT_TIMESTAMP()", "CURRENT_TIMESTAMP"), "current_timestamp()", "CURRENT_TIMESTAMP")
	if stmt, err = sqlparser.ParseStrictDDL(sql); nil != err {
		return nil, err
	}

	r, ok := stmt.(*sqlparser.DDL)
	if !ok {
		return nil, errors.New("input sql is not ddl")
	}
	basic.TableName = sqlparser.String(r.NewName)
	basic.ModelStructName = wrapperType.String(basic.TableName).SnakeCaseToCamel()

	// 生成model sql
	basic.ModelStruct = generateTable(basic.TableName, basic.ModelStructName, r.TableSpec.Columns)
	// 生成表字段定义
	columnDefined, _, getColumnFunc := generateTableColumnDefined(basic.ModelStructName, r.TableSpec.Columns)
	basic.ColumnDescDefined = columnDefined
	basic.ModelStruct += getColumnFunc
	basic.ModelStruct = basic.ColumnDescDefined + "\n" + basic.ModelStruct
	return basic, nil
}

// generateTable 生成表结构定义
//
// Author : go_developer@163.com<白茶清欢>
//
// Date : 20:29 2024/4/14
func generateTable(tableName string, modelStructName string, columnList []*sqlparser.ColumnDefinition) string {
	structResult := "type " + modelStructName + " struct { \n"

	for _, item := range columnList {
		comment := ""
		if item.Type.Comment == nil {
			comment = item.Name.String()
		} else {
			comment = string(item.Type.Comment.Val)
		}
		data := map[string]string{
			"{FIELD}":         wrapperType.String(item.Name.String()).SnakeCaseToCamel(),
			"{COLUMN}":        item.Name.String(),
			"{JSON_TAG}":      item.Name.String(),
			"{DEFAULT_VALUE}": "",
			"{COMMENT}":       comment,
			"{TYPE}":          sqlTypeMap[item.Type.Type],
		}
		/*if data["{FIELD}"] == "ID" {
			basic.PrimaryFieldType = data["{TYPE}"]
		}*/
		if item.Type.NotNull {
			data["{NOT_NULL}"] = "NOT NULL"
		}
		if nil != item.Type.Default {
			data["{DEFAULT_VALUE}"] += string(item.Type.Default.Val)
		}
		val := CreateSQLColumnTPL
		for k, v := range data {
			val = strings.ReplaceAll(val, k, v)
		}
		structResult += val + "\n"
	}
	structResult = structResult + "}"
	// 生成表名称获取方法
	tableFirst := string([]byte(tableName)[:1])
	funcTpl := `

// TableName 获取表名称
func ({{TABLE_FIRST}} {{TABLE_STRUCT_NAME}}) TableName() string {
return "{{TABLE_NAME}}"
}`
	replaceTable := map[string]string{
		"{{TABLE_FIRST}}":       tableFirst,
		"{{TABLE_STRUCT_NAME}}": modelStructName,
		"{{TABLE_NAME}}":        tableName,
	}
	for k, v := range replaceTable {
		funcTpl = strings.ReplaceAll(funcTpl, k, v)
	}
	structResult = structResult + funcTpl
	return structResult
}

// generateTableColumnDefined 生成表结构定义 + 表结构初始化
//
// Author : go_developer@163.com<白茶清欢>
//
// Date : 20:35 2024/4/14
func generateTableColumnDefined(modelStructName string, columnList []*sqlparser.ColumnDefinition) (string, string, string) {
	columnDefineName := modelStructName + "Column"
	structFieldResult := "type " + columnDefineName + " struct { \n"
	structFieldDescInstanceResult := "&" + columnDefineName + "{ \n"
	structFieldCommentInstanceResult := "map[string]string{ \n"
	for _, column := range columnList {
		dataMap := map[string]string{
			"{FIELD}":    wrapperType.String(column.Name.String()).SnakeCaseToCamel(),
			"{JSON_TAG}": column.Name.String(),
			"{FIELD_COMMENT}": wrapperType.TernaryOperator.String(
				column.Type.Comment == nil,
				wrapperType.String(column.Name.String()),
				wrapperType.String(string(column.Type.Comment.Val)),
			).Value(),
		}

		structFieldDefine := TableColumnTpl
		structFieldDescDefine := TableColumnDescTpl
		structFieldCommentDefine := TableColumnCommentTpl
		for k, v := range dataMap {
			structFieldDefine = strings.ReplaceAll(structFieldDefine, k, v)
			structFieldDescDefine = strings.ReplaceAll(structFieldDescDefine, k, v)
			structFieldCommentDefine = strings.ReplaceAll(structFieldCommentDefine, k, v)
		}
		structFieldResult += structFieldDefine + "\n"
		structFieldDescInstanceResult += structFieldDescDefine + ",\n"
		structFieldCommentInstanceResult += structFieldCommentDefine + ",\n"
	}
	structFieldResult += "}"
	structFieldDescInstanceResult += "}"
	structFieldCommentInstanceResult += "}"
	tableColumnFunction := `

// Columns 获取表字段定义
func ({TABLE_FIRST} {MODEL_STRUCT_NAME}) Columns() *{COLUMN_DEFINED} {
return {STRUCT_FIELD_DESC_DEFINED_RESULT}
}

// ColumnComment 获取表字段描述
func ({TABLE_FIRST} {MODEL_STRUCT_NAME}) ColumnComment() map[string]string {
return {STRUCT_FIELD_COMMENT_DEFINED_RESULT}
}
	`
	dataMap := map[string]string{
		"{COLUMN_DEFINED}":                      columnDefineName,
		"{TABLE_FIRST}":                         string([]byte(strings.ToLower(modelStructName))[:1]),
		"{MODEL_STRUCT_NAME}":                   modelStructName,
		"{STRUCT_FIELD_DESC_DEFINED_RESULT}":    structFieldDescInstanceResult,
		"{STRUCT_FIELD_COMMENT_DEFINED_RESULT}": structFieldCommentInstanceResult,
	}
	for k, v := range dataMap {
		tableColumnFunction = strings.ReplaceAll(tableColumnFunction, k, v)
	}
	return structFieldResult, structFieldDescInstanceResult, tableColumnFunction
}