package schema

import (
	
	
	
	

	
	
)

// RelationshipType relationship type
type RelationshipType string

const (
	HasOne    RelationshipType = "has_one"      // HasOneRel has one relationship
	HasMany   RelationshipType = "has_many"     // HasManyRel has many relationship
	BelongsTo RelationshipType = "belongs_to"   // BelongsToRel belongs to relationship
	Many2Many RelationshipType = "many_to_many" // Many2ManyRel many to many relationship
	has       RelationshipType = "has"
)

type Relationships struct {
	HasOne    []*Relationship
	BelongsTo []*Relationship
	HasMany   []*Relationship
	Many2Many []*Relationship
	Relations map[string]*Relationship

	EmbeddedRelations map[string]*Relationships
}

type Relationship struct {
	Name                     string
	Type                     RelationshipType
	Field                    *Field
	Polymorphic              *Polymorphic
	References               []*Reference
	Schema                   *Schema
	FieldSchema              *Schema
	JoinTable                *Schema
	foreignKeys, primaryKeys []string
}

type Polymorphic struct {
	PolymorphicID   *Field
	PolymorphicType *Field
	Value           string
}

type Reference struct {
	PrimaryKey    *Field
	PrimaryValue  string
	ForeignKey    *Field
	OwnPrimaryKey bool
}

func ( *Schema) ( *Field) *Relationship {
	var (
		        error
		 = reflect.New(.IndirectFieldType).Interface()
		   = &Relationship{
			Name:        .Name,
			Field:       ,
			Schema:      ,
			foreignKeys: toColumns(.TagSettings["FOREIGNKEY"]),
			primaryKeys: toColumns(.TagSettings["REFERENCES"]),
		}
	)

	 := .cacheStore

	if .FieldSchema,  = getOrParse(, , .namer);  != nil {
		.err = 
		return nil
	}

	if  := .TagSettings["POLYMORPHIC"];  != "" {
		.buildPolymorphicRelation(, , )
	} else if  := .TagSettings["MANY2MANY"];  != "" {
		.buildMany2ManyRelation(, , )
	} else if  := .TagSettings["BELONGSTO"];  != "" {
		.guessRelation(, , guessBelongs)
	} else {
		switch .IndirectFieldType.Kind() {
		case reflect.Struct:
			.guessRelation(, , guessGuess)
		case reflect.Slice:
			.guessRelation(, , guessHas)
		default:
			.err = fmt.Errorf("unsupported data type %v for %v on field %s", .FieldSchema, , .Name)
		}
	}

	if .Type == has {
		// don't add relations to embedded schema, which might be shared
		if .FieldSchema != .Schema && .Polymorphic == nil && .OwnerSchema == nil {
			.FieldSchema.Relationships.Relations["_"+.Schema.Name+"_"+.Name] = 
		}

		switch .IndirectFieldType.Kind() {
		case reflect.Struct:
			.Type = HasOne
		case reflect.Slice:
			.Type = HasMany
		}
	}

	if .err == nil {
		.setRelation()
		switch .Type {
		case HasOne:
			.Relationships.HasOne = append(.Relationships.HasOne, )
		case HasMany:
			.Relationships.HasMany = append(.Relationships.HasMany, )
		case BelongsTo:
			.Relationships.BelongsTo = append(.Relationships.BelongsTo, )
		case Many2Many:
			.Relationships.Many2Many = append(.Relationships.Many2Many, )
		}
	}

	return 
}

func ( *Schema) ( *Relationship) {
	// set non-embedded relation
	if  := .Relationships.Relations[.Name];  != nil {
		if len(.Field.BindNames) > 1 {
			.Relationships.Relations[.Name] = 
		}
	} else {
		.Relationships.Relations[.Name] = 
	}

	// set embedded relation
	if len(.Field.BindNames) <= 1 {
		return
	}
	 := &.Relationships
	for ,  := range .Field.BindNames {
		if  < len(.Field.BindNames)-1 {
			if .EmbeddedRelations == nil {
				.EmbeddedRelations = map[string]*Relationships{}
			}
			if  := .EmbeddedRelations[];  == nil {
				.EmbeddedRelations[] = &Relationships{}
			}
			 = .EmbeddedRelations[]
		} else {
			if .Relations == nil {
				.Relations = map[string]*Relationship{}
			}
			.Relations[.Name] = 
		}
	}
}

// User has many Toys, its `Polymorphic` is `Owner`, Pet has one Toy, its `Polymorphic` is `Owner`
//
//	type User struct {
//	  Toys []Toy `gorm:"polymorphic:Owner;"`
//	}
//	type Pet struct {
//	  Toy Toy `gorm:"polymorphic:Owner;"`
//	}
//	type Toy struct {
//	  OwnerID   int
//	  OwnerType string
//	}
func ( *Schema) ( *Relationship,  *Field,  string) {
	.Polymorphic = &Polymorphic{
		Value:           .Table,
		PolymorphicType: .FieldSchema.FieldsByName[+"Type"],
		PolymorphicID:   .FieldSchema.FieldsByName[+"ID"],
	}

	if ,  := .TagSettings["POLYMORPHICVALUE"];  {
		.Polymorphic.Value = strings.TrimSpace()
	}

	if .Polymorphic.PolymorphicType == nil {
		.err = fmt.Errorf("invalid polymorphic type %v for %v on field %s, missing field %s", .FieldSchema, , .Name, +"Type")
	}

	if .Polymorphic.PolymorphicID == nil {
		.err = fmt.Errorf("invalid polymorphic type %v for %v on field %s, missing field %s", .FieldSchema, , .Name, +"ID")
	}

	if .err == nil {
		.References = append(.References, &Reference{
			PrimaryValue: .Polymorphic.Value,
			ForeignKey:   .Polymorphic.PolymorphicType,
		})

		 := .PrioritizedPrimaryField
		if len(.foreignKeys) > 0 {
			if  = .LookUpField(.foreignKeys[0]);  == nil || len(.foreignKeys) > 1 {
				.err = fmt.Errorf("invalid polymorphic foreign keys %+v for %v on field %s", .foreignKeys, , .Name)
			}
		}

		if  == nil {
			.err = fmt.Errorf("invalid polymorphic type %v for %v on field %s, missing primaryKey field", .FieldSchema, , .Name)
			return
		}

		// use same data type for foreign keys
		if copyableDataType(.DataType) {
			.Polymorphic.PolymorphicID.DataType = .DataType
		}
		.Polymorphic.PolymorphicID.GORMDataType = .GORMDataType
		if .Polymorphic.PolymorphicID.Size == 0 {
			.Polymorphic.PolymorphicID.Size = .Size
		}

		.References = append(.References, &Reference{
			PrimaryKey:    ,
			ForeignKey:    .Polymorphic.PolymorphicID,
			OwnPrimaryKey: true,
		})
	}

	.Type = has
}

func ( *Schema) ( *Relationship,  *Field,  string) {
	.Type = Many2Many

	var (
		             error
		 []reflect.StructField
		       = map[string]*Field{}
		    = map[string]*Field{} // fix self join many2many
		  = map[string]*Field{}
		 = toColumns(.TagSettings["JOINFOREIGNKEY"])
		  = toColumns(.TagSettings["JOINREFERENCES"])
	)

	 := .PrimaryFields
	 := .FieldSchema.PrimaryFields

	if len(.foreignKeys) > 0 {
		 = []*Field{}
		for ,  := range .foreignKeys {
			if  := .LookUpField();  != nil {
				 = append(, )
			} else {
				.err = fmt.Errorf("invalid foreign key: %s", )
				return
			}
		}
	}

	if len(.primaryKeys) > 0 {
		 = []*Field{}
		for ,  := range .primaryKeys {
			if  := .FieldSchema.LookUpField();  != nil {
				 = append(, )
			} else {
				.err = fmt.Errorf("invalid foreign key: %s", )
				return
			}
		}
	}

	for ,  := range  {
		 := strings.Title(.Name) + .Name
		if len() >  {
			 = strings.Title([])
		}

		[] = 
		[] = 
		 = append(, reflect.StructField{
			Name:    ,
			PkgPath: .StructField.PkgPath,
			Type:    .StructField.Type,
			Tag: removeSettingFromTag(appendSettingFromTag(.StructField.Tag, "primaryKey"),
				"column", "autoincrement", "index", "unique", "uniqueindex"),
		})
	}

	for ,  := range  {
		 := strings.Title(.FieldSchema.Name) + .Name

		if ,  := [];  {
			if .Name != .FieldSchema.Name {
				 = inflection.Singular(.Name) + .Name
			} else {
				 += "Reference"
			}
		}

		if len() >  {
			 = strings.Title([])
		}

		[] = 

		if ,  := []; ! {
			[] = 
			 = append(, reflect.StructField{
				Name:    ,
				PkgPath: .StructField.PkgPath,
				Type:    .StructField.Type,
				Tag: removeSettingFromTag(appendSettingFromTag(.StructField.Tag, "primaryKey"),
					"column", "autoincrement", "index", "unique", "uniqueindex"),
			})
		}
	}

	 = append(, reflect.StructField{
		Name: strings.Title(.Name) + .Name,
		Type: .ModelType,
		Tag:  `gorm:"-"`,
	})

	if .JoinTable,  = Parse(reflect.New(reflect.StructOf()).Interface(), .cacheStore, .namer);  != nil {
		.err = 
	}
	.JoinTable.Name = 
	.JoinTable.Table = .namer.JoinTableName()
	.JoinTable.PrimaryFields = make([]*Field, 0, len(.JoinTable.Fields))

	 := .Schema.Name
	 := .FieldSchema.Name
	if  ==  {
		 = .Field.Name
	}

	if ,  := .JoinTable.Relationships.Relations[]; ! {
		.JoinTable.Relationships.Relations[] = &Relationship{
			Name:        ,
			Type:        BelongsTo,
			Schema:      .JoinTable,
			FieldSchema: .Schema,
		}
	} else {
		.JoinTable.Relationships.Relations[].References = []*Reference{}
	}

	if ,  := .JoinTable.Relationships.Relations[]; ! {
		.JoinTable.Relationships.Relations[] = &Relationship{
			Name:        ,
			Type:        BelongsTo,
			Schema:      .JoinTable,
			FieldSchema: .FieldSchema,
		}
	} else {
		.JoinTable.Relationships.Relations[].References = []*Reference{}
	}

	// build references
	for ,  := range .JoinTable.Fields {
		if .Creatable || .Readable || .Updatable {
			// use same data type for foreign keys
			if copyableDataType([.Name].DataType) {
				.DataType = [.Name].DataType
			}
			.GORMDataType = [.Name].GORMDataType
			if .Size == 0 {
				.Size = [.Name].Size
			}
			.JoinTable.PrimaryFields = append(.JoinTable.PrimaryFields, )

			if ,  := [.Name];  {
				 := .JoinTable.Relationships.Relations[]
				.Field = .Field
				.References = append(.References, &Reference{
					PrimaryKey: ,
					ForeignKey: ,
				})

				.References = append(.References, &Reference{
					PrimaryKey:    ,
					ForeignKey:    ,
					OwnPrimaryKey: true,
				})
			}

			if ,  := [.Name];  {
				 := .JoinTable.Relationships.Relations[]
				if .Field == nil {
					.Field = .Field
				}
				.References = append(.References, &Reference{
					PrimaryKey: ,
					ForeignKey: ,
				})

				.References = append(.References, &Reference{
					PrimaryKey: ,
					ForeignKey: ,
				})
			}
		}
	}
}

type guessLevel int

const (
	guessGuess guessLevel = iota
	guessBelongs
	guessEmbeddedBelongs
	guessHas
	guessEmbeddedHas
)

func ( *Schema) ( *Relationship,  *Field,  guessLevel) {
	var (
		,  []*Field
		,  = , .FieldSchema
		                           = 
	)

	if  == guessGuess {
		if .Schema == .FieldSchema {
			 = guessBelongs
		} else {
			 = guessHas
		}
	}

	 := func() {
		switch  {
		case guessGuess:
			.(, , guessBelongs)
		case guessBelongs:
			.(, , guessEmbeddedBelongs)
		case guessEmbeddedBelongs:
			.(, , guessHas)
		case guessHas:
			.(, , guessEmbeddedHas)
		// case guessEmbeddedHas:
		default:
			.err = fmt.Errorf("invalid field found for struct %v's field %s: define a valid foreign key for relations or implement the Valuer/Scanner interface", , .Name)
		}
	}

	switch  {
	case guessBelongs:
		,  = .FieldSchema, 
	case guessEmbeddedBelongs:
		if .OwnerSchema == nil {
			()
			return
		}
		,  = .FieldSchema, .OwnerSchema
	case guessHas:
	case guessEmbeddedHas:
		if .OwnerSchema == nil {
			()
			return
		}
		,  = .OwnerSchema, .FieldSchema
	}

	if len(.foreignKeys) > 0 {
		for ,  := range .foreignKeys {
			 := .LookUpField()
			if  == nil {
				()
				return
			}
			 = append(, )
		}
	} else {
		 := .Name
		if  == "" {
			 = .FieldSchema.Name
		}

		if len(.primaryKeys) > 0 {
			for ,  := range .primaryKeys {
				if  := .LookUpField();  != nil {
					 = append(, )
				}
			}
		} else {
			 = .PrimaryFields
		}

	:
		for ,  := range  {
			 :=  + .Name
			if  == guessBelongs {
				 = .Name + .Name
			}

			 := []string{}
			if len() == 1 {
				 = append(, strings.TrimSuffix(, .Name)+"ID", strings.TrimSuffix(, .Name)+"Id", .namer.ColumnName(.Table, strings.TrimSuffix(, .Name)+"ID"))
			}

			for ,  := range  {
				if  := .LookUpFieldByBindName(.BindNames, );  != nil {
					 = append(, )
					 = append(, )
					continue 
				}
			}
			for ,  := range  {
				if  := .LookUpField();  != nil {
					 = append(, )
					 = append(, )
					continue 
				}
			}
		}
	}

	switch {
	case len() == 0:
		()
		return
	case len(.primaryKeys) > 0:
		for ,  := range .primaryKeys {
			if  := .LookUpField();  != nil {
				if len() < +1 {
					 = append(, )
				} else if  != [] {
					()
					return
				}
			} else {
				()
				return
			}
		}
	case len() == 0:
		if len() == 1 && .PrioritizedPrimaryField != nil {
			 = append(, .PrioritizedPrimaryField)
		} else if len(.PrimaryFields) == len() {
			 = append(, .PrimaryFields...)
		} else {
			()
			return
		}
	}

	// build references
	for ,  := range  {
		// use same data type for foreign keys
		if copyableDataType([].DataType) {
			.DataType = [].DataType
		}
		.GORMDataType = [].GORMDataType
		if .Size == 0 {
			.Size = [].Size
		}

		.References = append(.References, &Reference{
			PrimaryKey:    [],
			ForeignKey:    ,
			OwnPrimaryKey: ( ==  &&  == guessHas) || (.OwnerSchema ==  &&  == guessEmbeddedHas),
		})
	}

	if  == guessHas ||  == guessEmbeddedHas {
		.Type = has
	} else {
		.Type = BelongsTo
	}
}

type Constraint struct {
	Name            string
	Field           *Field
	Schema          *Schema
	ForeignKeys     []*Field
	ReferenceSchema *Schema
	References      []*Field
	OnDelete        string
	OnUpdate        string
}

func ( *Relationship) () *Constraint {
	 := .Field.TagSettings["CONSTRAINT"]
	if  == "-" {
		return nil
	}

	if .Type == BelongsTo {
		for ,  := range .FieldSchema.Relationships.Relations {
			if  !=  && .FieldSchema == .Schema && len(.References) == len(.References) {
				 := true
				for ,  := range .References {
					if !(.References[].PrimaryKey == .PrimaryKey && .References[].ForeignKey == .ForeignKey &&
						.References[].PrimaryValue == .PrimaryValue) {
						 = false
					}
				}

				if  {
					return nil
				}
			}
		}
	}

	var (
		     string
		      = strings.Index(, ",")
		 = ParseTagSetting(, ",")
	)

	// optimize match english letters and midline
	// The following code is basically called in for.
	// In order to avoid the performance problems caused by repeated compilation of regular expressions,
	// it only needs to be done once outside, so optimization is done here.
	if  != -1 && regEnLetterAndMidline.MatchString([0:]) {
		 = [0:]
	} else {
		 = .Schema.namer.RelationshipFKName(*)
	}

	 := Constraint{
		Name:     ,
		Field:    .Field,
		OnUpdate: ["ONUPDATE"],
		OnDelete: ["ONDELETE"],
	}

	for ,  := range .References {
		if .PrimaryKey != nil && (.JoinTable == nil || .OwnPrimaryKey) {
			.ForeignKeys = append(.ForeignKeys, .ForeignKey)
			.References = append(.References, .PrimaryKey)

			if .OwnPrimaryKey {
				.Schema = .ForeignKey.Schema
				.ReferenceSchema = .Schema
			} else {
				.Schema = .Schema
				.ReferenceSchema = .PrimaryKey.Schema
			}
		}
	}

	return &
}

func ( *Relationship) ( context.Context,  reflect.Value) ( []clause.Expression) {
	 := .FieldSchema.Table
	 := []*Field{}
	 := []string{}

	if .JoinTable != nil {
		 = .JoinTable.Table
		for ,  := range .References {
			if .OwnPrimaryKey {
				 = append(, .PrimaryKey)
				 = append(, .ForeignKey.DBName)
			} else if .PrimaryValue != "" {
				 = append(, clause.Eq{
					Column: clause.Column{Table: .JoinTable.Table, Name: .ForeignKey.DBName},
					Value:  .PrimaryValue,
				})
			} else {
				 = append(, clause.Eq{
					Column: clause.Column{Table: .JoinTable.Table, Name: .ForeignKey.DBName},
					Value:  clause.Column{Table: .FieldSchema.Table, Name: .PrimaryKey.DBName},
				})
			}
		}
	} else {
		for ,  := range .References {
			if .OwnPrimaryKey {
				 = append(, .ForeignKey.DBName)
				 = append(, .PrimaryKey)
			} else if .PrimaryValue != "" {
				 = append(, clause.Eq{
					Column: clause.Column{Table: .FieldSchema.Table, Name: .ForeignKey.DBName},
					Value:  .PrimaryValue,
				})
			} else {
				 = append(, .PrimaryKey.DBName)
				 = append(, .ForeignKey)
			}
		}
	}

	,  := GetIdentityFieldValuesMap(, , )
	,  := ToQueryValues(, , )

	 = append(, clause.IN{Column: , Values: })
	return
}

func copyableDataType( DataType) bool {
	for ,  := range []string{"auto_increment", "primary key"} {
		if strings.Contains(strings.ToLower(string()), ) {
			return false
		}
	}
	return true
}