{{/*
Copyright 2019-present Facebook Inc. All rights reserved.
This source code is licensed under the Apache 2.0 license found
in the LICENSE file in the root directory of this source tree.
*/}}

{{ define "mutation" }}

{{ $pkg := base $.Config.Package }}
{{ template "header" $ }}

import (
	"sync"

	{{- range $n := $.Nodes }}
		"{{ $.Config.Package }}/{{ $n.Package }}"
	{{- end }}

	"github.com/facebookincubator/ent"
)

const (
	// Operation types.
	OpCreate    = ent.OpCreate
	OpDelete    = ent.OpDelete
	OpDeleteOne = ent.OpDeleteOne
	OpUpdate    = ent.OpUpdate
	OpUpdateOne = ent.OpUpdateOne

	// Node types.
	{{- range $n := $.Nodes }}
		Type{{ $n.Name }} = "{{ $n.Name }}"
	{{- end }}
)

{{ range $n := $.Nodes }}

{{ $mutation := $n.MutationName }}
// {{ $mutation }} represents an operation that mutate the {{ plural $n.Name }}
// nodes in the graph.
type {{ $mutation }} struct {
	config
	op Op
	typ string
	{{ $n.ID.BuilderField }} *{{ $n.ID.Type }}
	{{- range $f := $n.Fields }}
		{{ $f.BuilderField }} *{{ $f.Type }}
		{{- if and $f.Type.Numeric $f.ConvertedToBasic }}
			add{{ $f.BuilderField }} *{{ $f.Type }}
		{{- end }}
	{{- end }}
	clearedFields map[string]struct{}
	{{- range $e := $n.Edges }}
		{{- if $e.Unique }}
            {{ $e.BuilderField }} *{{ $e.Type.ID.Type }}
			cleared{{ $e.BuilderField }} bool
		{{- else }}
            {{ $e.BuilderField }} map[{{ $e.Type.ID.Type }}]struct{}
			removed{{ $e.BuilderField }} map[{{ $e.Type.ID.Type }}]struct{}
		{{- end }}
	{{- end }}
	done bool
	oldValue func(context.Context) (*{{ $n.Name }}, error)
}

var _ ent.Mutation = (*{{ $mutation }})(nil)

{{ $mutationOption := print (camel $n.Name) "Option" }}
// {{ $mutationOption }} allows to manage the mutation configuration using functional options.
type {{ $mutationOption }} func(*{{ $mutation }})

// new{{ $mutation }} creates new mutation for $n.Name.
func new{{ $mutation }}(c config, op Op, opts ...{{ $mutationOption }}) *{{ $mutation }} {
	m := &{{ $mutation }}{
		config:        c,
		op:            op,
		typ:           Type{{ $n.Name }},
		clearedFields: make(map[string]struct{}),
	}
	for _, opt := range opts {
		opt(m)
	}
	return m
}

{{ $opt := print "with" $n.Name "ID" }}
// {{ $opt }} sets the id field of the mutation.
func {{ $opt }}(id {{ $n.ID.Type }}) {{ $mutationOption }} {
	return func(m *{{ $mutation }}) {
		var (
			err error
			once sync.Once
			value *{{ $n.Name }}
		)
		m.oldValue = func(ctx context.Context) (*{{ $n.Name }}, error) {
			once.Do(func() {
				if m.done {
					err = fmt.Errorf("querying old values post mutation is not allowed")
				} else {
					value, err = m.Client().{{ $n.Name }}.Get(ctx, id)
				}
			})
			return value, err
		}
		m.{{ $n.ID.BuilderField }} = &id
	}
}

{{ $opt = print "with" $n.Name }}
// {{ $opt }} sets the old {{ $n.Name }} of the mutation.
func {{ $opt }}(node *{{ $n.Name }}) {{ $mutationOption }} {
	return func(m *{{ $mutation }}) {
		m.oldValue = func(context.Context) (*{{ $n.Name }}, error) {
			return node, nil
		}
		m.{{ $n.ID.BuilderField }} = &node.ID
	}
}

// Client returns a new `ent.Client` from the mutation. If the mutation was
// executed in a transaction (ent.Tx), a transactional client is returned.
func (m {{ $mutation }}) Client() *Client {
	client := &Client{config: m.config}
	client.init()
	return client
}

// Tx returns an `ent.Tx` for mutations that were executed in transactions;
// it returns an error otherwise.
func (m {{ $mutation }}) Tx() (*Tx, error) {
	if 	_, ok := m.driver.(*txDriver); !ok {
		return nil, fmt.Errorf("{{ $pkg }}: mutation is not running in a transaction")
	}
	tx := &Tx{config: m.config}
	tx.init()
	return tx, nil
}

{{- if $n.ID.UserDefined }}
	// SetID sets the value of the id field. Note that, this
	// operation is accepted only on {{ $n.Name }} creation.
	func (m *{{ $mutation }}) SetID(id {{ $n.ID.Type }}) {
		m.{{ $n.ID.BuilderField }} = &id
	}
{{- end }}

// ID returns the id value in the mutation. Note that, the id
// is available only if it was provided to the builder.
func (m *{{ $mutation }}) ID() (id {{ $n.ID.Type }}, exists bool) {
	if m.{{ $n.ID.BuilderField }} == nil {
		return
	}
	return *m.{{ $n.ID.BuilderField }}, true
}

{{ range $f := $n.Fields }}
	{{ $p := receiver $f.Type.String }}{{ if eq $p "m" }} {{ $p = "value" }} {{ end }}
	{{ $func := print "Set" $f.StructField }}
	{{ $const := print $n.Package "." $f.Constant }}
	// {{ $func }} sets the {{ $f.Name }} field.
	func (m *{{ $mutation }}) {{ $func }}({{ $p }} {{ $f.Type }}) {
		m.{{ $f.BuilderField }} = &{{ $p }}
		{{- /* setting numeric type override previous calls to Add. */}}
		{{- if and $f.Type.Numeric $f.ConvertedToBasic }}
			m.add{{ $f.BuilderField }} = nil
		{{- end }}
	}

	// {{ $f.MutationGet }} returns the {{ $f.Name }} value in the mutation.
	func (m *{{ $mutation }}) {{ $f.MutationGet }}() (r {{ $f.Type }}, exists bool) {
		v := m.{{ $f.BuilderField }}
		if v == nil {
			return
		}
		return *v, true
	}

	// {{ $f.MutationGetOld }} returns the old {{ $f.Name }} value of the {{ $n.Name }}.
	// If the {{ $n.Name }} object wasn't provided to the builder, the object is fetched
	// from the database.
	// An error is returned if the mutation operation is not UpdateOne, or database query fails.
	func (m *{{ $mutation }}) {{ $f.MutationGetOld }}(ctx context.Context) (v {{ if $f.Nillable }}*{{ end }}{{ $f.Type }}, err error) {
		if !m.op.Is(OpUpdateOne) {
			return v, fmt.Errorf("{{ $f.MutationGetOld }} is allowed only on UpdateOne operations")
		}
		if m.{{ $n.ID.BuilderField }} == nil || m.oldValue == nil {
			return v, fmt.Errorf("{{ $f.MutationGetOld }} requires an ID field in the mutation")
		}
		oldValue, err := m.oldValue(ctx)
		if err != nil {
			return v, fmt.Errorf("querying old value for {{ $f.MutationGetOld }}: %w", err)
		}
		return oldValue.{{ $f.StructField }}, nil
	}

	{{ if and $f.Type.Numeric $f.ConvertedToBasic }}
		{{ $func := print "Add" $f.StructField }}
		// {{ $func }} adds {{ $p }} to {{ $f.Name }}.
		func (m *{{ $mutation }}) {{ $func }}({{ $p }} {{ $f.Type }}) {
			{{- if $f.HasGoType }}
			{{- else }}
			{{- end }}
			if m.add{{ $f.BuilderField }} != nil {
				*m.add{{ $f.BuilderField }} += {{ $p }}
			} else {
				m.add{{ $f.BuilderField }} = &{{ $p }}
			}
		}

		// Added{{ $f.StructField }} returns the value that was added to the {{ $f.Name }} field in this mutation.
		func (m *{{ $mutation }}) Added{{ $f.StructField }}() (r {{ $f.Type }}, exists bool) {
			v := m.add{{ $f.BuilderField }}
			if v == nil {
				return
			}
			return *v, true
		}
	{{ end }}

	{{ if $f.Optional }}
		{{ $func := print "Clear" $f.StructField }}
		// {{ $func }} clears the value of {{ $f.Name }}.
		func (m *{{ $mutation }}) {{ $func }}() {
			m.{{ $f.BuilderField }} = nil
			{{- if and $f.Type.Numeric $f.ConvertedToBasic }}
				m.add{{ $f.BuilderField }} = nil
			{{- end }}
			m.clearedFields[{{ $const }}] = struct{}{}
		}

		{{ $func = print $f.StructField "Cleared" }}
		// {{ $func }} returns if the field {{ $f.Name }} was cleared in this mutation.
		func (m *{{ $mutation }}) {{ $func }}() bool {
			_, ok := m.clearedFields[{{ $const }}]
			return ok
		}
	{{ end }}

	{{ $func = $f.MutationReset }}
	// {{ $func }} reset all changes of the "{{ $f.Name }}" field.
	func (m *{{ $mutation }}) {{ $func }}() {
		m.{{ $f.BuilderField }} = nil
		{{- if and $f.Type.Numeric $f.ConvertedToBasic }}
			m.add{{ $f.BuilderField }} = nil
		{{- end }}
		{{- if $f.Optional }}
			delete(m.clearedFields, {{ $const }})
		{{- end }}
	}
{{ end }}


{{ range $e := $n.Edges }}
	{{ $op := "add" }}{{ if $e.Unique }}{{ $op = "set" }}{{ end }}
	{{ $idsFunc := print (pascal $op) (singular $e.Name | pascal) "IDs" }}{{ if $e.Unique }}{{ $idsFunc = print (pascal $op) (pascal $e.Name) "ID" }}{{ end }}
	// {{ $idsFunc }} {{ $op }}s the {{ $e.Name }} edge to {{ $e.Type.Name }} by id{{ if not $e.Unique }}s{{ end }}.
	func (m *{{ $mutation }}) {{ $idsFunc }}({{ if $e.Unique }}id{{ else }}ids ...{{ end }} {{ $e.Type.ID.Type }}) {
		{{- if $e.Unique }}
			m.{{ $e.BuilderField }} = &id
		{{- else }}
			if m.{{ $e.BuilderField }} == nil {
				m.{{ $e.BuilderField }} = make(map[{{ $e.Type.ID.Type }}]struct{})
			}
			for i := range ids {
				m.{{ $e.BuilderField }}[ids[i]] = struct{}{}
			}
		{{- end }}
	}
	{{ if $e.Unique }}
		{{ $func := print "Clear" $e.StructField }}
		// {{ $func }} clears the {{ $e.Name }} edge to {{ $e.Type.Name }}.
		func (m *{{ $mutation }}) {{ $func }}() {
			m.cleared{{ $e.BuilderField }} = true
		}

		{{ $func = print $e.StructField "Cleared" }}
		// {{ $func }} returns if the edge {{ $e.Name }} was cleared.
		func (m *{{ $mutation }}) {{ $func }}() bool {
			return m.cleared{{ $e.BuilderField }}
		}

		// {{ $e.StructField }}ID returns the {{ $e.Name }} id in the mutation.
		func (m *{{ $mutation }}) {{ $e.StructField }}ID() (id {{ $e.Type.ID.Type }}, exists bool) {
			if m.{{ $e.BuilderField }} != nil {
				return *m.{{ $e.BuilderField }}, true
			}
			return
		}
	{{ else }}
		{{ $p := lower (printf "%.1s" $e.Type.Name) }}
		{{ $idsFunc := print "Remove" (singular $e.Name | pascal) "IDs" }}
		// {{ $idsFunc }} removes the {{ $e.Name }} edge to {{ $e.Type.Name }} by ids.
		func (m *{{ $mutation }}) {{ $idsFunc }}(ids ...{{ $e.Type.ID.Type }}) {
			if m.removed{{ $e.BuilderField }} == nil {
				m.removed{{ $e.BuilderField }} = make(map[{{ $e.Type.ID.Type }}]struct{})
			}
			{{- if $e.Unique }}
				m.removed{{ $e.BuilderField }}[id] = struct{}{}
			{{- else }}
				for i := range ids {
					m.removed{{ $e.BuilderField }}[ids[i]] = struct{}{}
				}
			{{- end }}
		}

		{{ $func := print "Removed" $e.StructField }}
		// {{ $func }} returns the removed ids of {{ $e.Name }}.
		func (m *{{ $mutation }}) {{ $func }}IDs() (ids []{{ $e.Type.ID.Type }}) {
			for id := range m.removed{{ $e.BuilderField }} {
				ids = append(ids, id)
			}
			return
		}
	{{ end }}

	// {{ $e.StructField }}IDs returns the {{ $e.Name }} ids in the mutation.
    {{- if $e.Unique }}
		// Note that ids always returns len(ids) <= 1 for unique edges, and you should use
		// {{ $e.StructField }}ID instead. It exists only for internal usage by the builders.
	{{- end }}
	func (m *{{ $mutation }}) {{ $e.StructField }}IDs() (ids []{{ $e.Type.ID.Type }}) {
    	{{- if $e.Unique }}
			if id := m.{{ $e.BuilderField }}; id != nil {
				ids = append(ids, *id)
			}
		{{- else }}
			for id := range m.{{ $e.BuilderField }} {
				ids = append(ids, id)
			}
		{{- end}}
		return
	}


	{{ $func := $e.MutationReset }}
	// {{ $func }} reset all changes of the "{{ $e.Name }}" edge.
	func (m *{{ $mutation }}) {{ $func }}() {
		m.{{ $e.BuilderField }} = nil
		{{- if $e.Unique }}
			m.cleared{{ $e.BuilderField }} = false
		{{- else }}
			m.removed{{ $e.BuilderField }} = nil
		{{- end }}
	}
{{ end }}


// Op returns the operation name.
func (m *{{ $mutation }}) Op() Op {
	return m.op
}

// Type returns the node type of this mutation ({{ $n.Name }}).
func (m *{{ $mutation }}) Type() string {
	return m.typ
}

// Fields returns all fields that were changed during
// this mutation. Note that, in order to get all numeric
// fields that were in/decremented, call AddedFields().
func (m *{{ $mutation }}) Fields() []string {
	fields := make([]string, 0, {{ len $n.Fields }})
	{{- range $f := $n.Fields }}
		{{- $const := print $n.Package "." $f.Constant }}
		if m.{{ $f.BuilderField }} != nil {
			fields = append(fields, {{ $const }})
		}
	{{- end }}
	return fields
}

// Field returns the value of a field with the given name.
// The second boolean value indicates that this field was
// not set, or was not define in the schema.
func (m *{{ $mutation }}) Field(name string) (ent.Value, bool) {
	{{- with $n.Fields }}
		switch name {
		{{- range $f := $n.Fields }}
			{{- $const := print $n.Package "." $f.Constant }}
			case {{ $const }}:
				return  m.{{ $f.MutationGet }}()
		{{- end }}
		}
	{{- end }}
	return nil, false
}


// OldField returns the old value of the field from the database.
// An error is returned if the mutation operation is not UpdateOne,
// or the query to the database was failed.
func (m *{{ $mutation }}) OldField(ctx context.Context, name string) (ent.Value, error) {
	{{- with $n.Fields }}
		switch name {
		{{- range $f := . }}
			{{- $const := print $n.Package "." $f.Constant }}
			case {{ $const }}:
				return  m.{{ $f.MutationGetOld }}(ctx)
		{{- end }}
		}
	{{- end }}
	return nil, fmt.Errorf("unknown {{ $n.Name }} field %s", name)
}

// SetField sets the value for the given name. It returns an
// error if the field is not defined in the schema, or if the
// type mismatch the field type.
func (m *{{ $mutation }}) SetField(name string, value ent.Value) error {
	switch name {
	{{- range $f := $n.Fields }}
		{{- $const := print $n.Package "." $f.Constant }}
		case {{ $const }}:
			v, ok := value.({{ $f.Type }})
			if !ok {
				return fmt.Errorf("unexpected type %T for field %s", value, name)
			}
			m.Set{{ $f.StructField }}(v)
			return nil
	{{- end }}
	}
	return fmt.Errorf("unknown {{ $n.Name }} field %s", name)
}

// AddedFields returns all numeric fields that were incremented
// or decremented during this mutation.
func (m *{{ $mutation }}) AddedFields() []string {
	{{- if $n.HasNumeric }}
		var fields []string
		{{- range $f := $n.Fields }}
			{{- if and $f.Type.Numeric $f.ConvertedToBasic }}
				{{- $const := print $n.Package "." $f.Constant }}
				if m.add{{ $f.BuilderField }} != nil {
					fields = append(fields, {{ $const }})
				}
			{{- end }}
		{{- end }}
		return fields
	{{- else }}
		return nil
	{{- end }}
}

// AddedField returns the numeric value that was in/decremented
// from a field with the given name. The second value indicates
// that this field was not set, or was not define in the schema.
func (m *{{ $mutation }}) AddedField(name string) (ent.Value, bool) {
	{{- if $n.HasNumeric }}
		switch name {
		{{- range $f := $n.Fields }}
			{{- if and $f.Type.Numeric $f.ConvertedToBasic }}
				{{- $const := print $n.Package "." $f.Constant }}
				case {{ $const }}:
					return m.Added{{ $f.StructField }}()
			{{- end }}
		{{- end }}
		}
	{{- end }}
	return nil, false
}

// AddField adds the value for the given name. It returns an
// error if the field is not defined in the schema, or if the
// type mismatch the field type.
func (m *{{ $mutation }}) AddField(name string, value ent.Value) error {
	{{- with $n.Fields }}
		switch name {
		{{- range $f := $n.Fields }}
			{{- if and $f.Type.Numeric $f.ConvertedToBasic }}
				{{- $const := print $n.Package "." $f.Constant }}
				case {{ $const }}:
					v, ok := value.({{ $f.Type }})
					if !ok {
						return fmt.Errorf("unexpected type %T for field %s", value, name)
					}
					m.Add{{ $f.StructField }}(v)
					return nil
			{{- end }}
		{{- end }}
		}
	{{- end }}
	return fmt.Errorf("unknown {{ $n.Name }} numeric field %s", name)
}


// ClearedFields returns all nullable fields that were cleared
// during this mutation.
func (m *{{ $mutation }}) ClearedFields() []string {
	{{- if $n.HasOptional }}
		var fields []string
		{{- range $f := $n.Fields }}
			{{- if $f.Optional }}
				{{- $const := print $n.Package "." $f.Constant }}
				if m.FieldCleared({{ $const }}) {
					fields = append(fields, {{ $const }})
				}
			{{- end }}
		{{- end }}
		return fields
	{{- else }}
		return nil
	{{- end }}
}

// FieldCleared returns a boolean indicates if this field was
// cleared in this mutation.
func (m *{{ $mutation }}) FieldCleared(name string) bool {
	_, ok := m.clearedFields[name]
	return ok
}

// ClearField clears the value for the given name. It returns an
// error if the field is not defined in the schema.
func (m *{{ $mutation }}) ClearField(name string) error {
	{{- if $n.HasOptional }}
		switch name {
		{{- range $f := $n.Fields }}
			{{- if $f.Optional }}
				{{- $const := print $n.Package "." $f.Constant }}
				case {{ $const }}:
					m.Clear{{ $f.StructField }}()
					return nil
			{{- end }}
		{{- end }}
		}
	{{- end }}
	return fmt.Errorf("unknown {{ $n.Name }} nullable field %s", name)
}


// ResetField resets all changes in the mutation regarding the
// given field name. It returns an error if the field is not
// defined in the schema.
func (m *{{ $mutation }}) ResetField(name string) error {
	{{- with $n.Fields }}
		switch name {
		{{- range $f := $n.Fields }}
			{{- $const := print $n.Package "." $f.Constant }}
			case {{ $const }}:
				m.{{ $f.MutationReset }}()
				return nil
		{{- end }}
		}
	{{- end }}
	return fmt.Errorf("unknown {{ $n.Name }} field %s", name)
}

// AddedEdges returns all edge names that were set/added in this
// mutation.
func (m *{{ $mutation }}) AddedEdges() []string {
	edges := make([]string, 0, {{ len $n.Edges }})
	{{- range $e := $n.Edges }}
		if m.{{ $e.BuilderField }} != nil {
			{{- $const := print $n.Package "." $e.Constant }}
			edges = append(edges, {{ $const }})
		}
	{{- end }}
	return edges
}

// AddedIDs returns all ids (to other nodes) that were added for
// the given edge name.
func (m *{{ $mutation }}) AddedIDs(name string) []ent.Value {
	{{- with $n.Edges }}
		switch name {
		{{- range $e := $n.Edges }}
			{{- $const := print $n.Package "." $e.Constant }}
			case {{ $const }}:
				{{- if $e.Unique }}
					if id := m.{{ $e.BuilderField }}; id != nil {
						return []ent.Value{*id}
					}
				{{- else }}
					ids := make([]ent.Value, 0, len(m.{{ $e.BuilderField }}))
					for id := range m.{{ $e.BuilderField }} {
						ids = append(ids, id)
					}
					return ids
				{{- end }}
		{{- end }}
		}
	{{- end }}
	return nil
}

// RemovedEdges returns all edge names that were removed in this
// mutation.
func (m *{{ $mutation }}) RemovedEdges() []string {
	edges := make([]string, 0, {{ len $n.Edges }})
	{{- range $e := $n.Edges }}
		{{- if not $e.Unique }}
			if m.removed{{ $e.BuilderField }} != nil {
				{{- $const := print $n.Package "." $e.Constant }}
				edges = append(edges, {{ $const }})
			}
		{{- end }}
	{{- end }}
	return edges
}

// RemovedIDs returns all ids (to other nodes) that were removed for
// the given edge name.
func (m *{{ $mutation }}) RemovedIDs(name string) []ent.Value {
	{{- with $n.Edges }}
		switch name {
		{{- range $e := $n.Edges }}
			{{- if not $e.Unique }}
				{{- $const := print $n.Package "." $e.Constant }}
				case {{ $const }}:
					ids := make([]ent.Value, 0, len(m.removed{{ $e.BuilderField }}))
					for id := range m.removed{{ $e.BuilderField }} {
						ids = append(ids, id)
					}
					return ids
			{{- end }}
		{{- end }}
		}
	{{- end }}
	return nil
}

// ClearedEdges returns all edge names that were cleared in this
// mutation.
func (m *{{ $mutation }}) ClearedEdges() []string {
	edges := make([]string, 0, {{ len $n.Edges }})
	{{- range $e := $n.Edges }}
		{{- if $e.Unique }}
			if m.cleared{{ $e.BuilderField }} {
				{{- $const := print $n.Package "." $e.Constant }}
				edges = append(edges, {{ $const }})
			}
		{{- end }}
	{{- end }}
	return edges
}

// EdgeCleared returns a boolean indicates if this edge was
// cleared in this mutation.
func (m *{{ $mutation }}) EdgeCleared(name string) bool {
	{{- with $n.Edges }}
		switch name {
		{{- range $e := $n.Edges }}
			{{- if $e.Unique }}
				{{- $const := print $n.Package "." $e.Constant }}
				case {{ $const }}:
					return m.cleared{{ $e.BuilderField }}
			{{- end }}
		{{- end }}
		}
	{{- end }}
	return false
}

// ClearEdge clears the value for the given name. It returns an
// error if the edge name is not defined in the schema.
func (m *{{ $mutation }}) ClearEdge(name string) error {
	{{- with $n.Edges }}
		switch name {
		{{- range $e := $n.Edges }}
			{{- if $e.Unique }}
				{{- $const := print $n.Package "." $e.Constant }}
				case {{ $const }}:
					m.Clear{{ $e.StructField }}()
					return nil
			{{- end }}
		{{- end }}
		}
	{{- end }}
	return fmt.Errorf("unknown {{ $n.Name }} unique edge %s", name)
}

// ResetEdge resets all changes in the mutation regarding the
// given edge name. It returns an error if the edge is not
// defined in the schema.
func (m *{{ $mutation }}) ResetEdge(name string) error {
	{{- with $n.Edges }}
		switch name {
		{{- range $e := $n.Edges }}
			{{- $const := print $n.Package "." $e.Constant }}
			case {{ $const }}:
				m.{{ $e.MutationReset }}()
				return nil
		{{- end }}
		}
	{{- end }}
	return fmt.Errorf("unknown {{ $n.Name }} edge %s", name)
}
{{ end }}

{{ end }}