1. 1
2. 2
3. 3
4. 4
5. 5
6. 6
7. 7
8. 8
9. 9
10. 10
11. 11
12. 12
13. 13
14. 14
15. 15
16. 16
17. 17
18. 18
19. 19
20. 20
21. 21
22. 22
23. 23
24. 24
25. 25
26. 26
27. 27
28. 28
29. 29
30. 30
31. 31
32. 32
33. 33
34. 34
35. 35
36. 36
37. 37
38. 38
39. 39
40. 40
41. 41
42. 42
43. 43
44. 44
45. 45
46. 46
47. 47
48. 48
49. 49
50. 50
51. 51
52. 52
53. 53
54. 54
55. 55
56. 56
57. 57
58. 58
59. 59
60. 60
61. 61
62. 62
63. 63
64. 64
65. 65
66. 66
67. 67
68. 68
69. 69
70. 70
71. 71
72. 72
73. 73
74. 74
75. 75
76. 76
77. 77
78. 78
79. 79
80. 80
81. 81
82. 82
83. 83
84. 84
85. 85
86. 86
87. 87
88. 88
89. 89
90. 90
91. 91
92. 92
93. 93
94. 94
95. 95
96. 96
97. 97
98. 98
99. 99
100. 100
101. 101
102. 102
103. 103
104. 104
105. 105
106. 106
107. 107
108. 108
109. 109
110. 110
111. 111
112. 112
113. 113
114. 114
115. 115
116. 116
117. 117
118. 118
119. 119

// Copyright (C) MongoDB, Inc. 2017-present.
//
// 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

package bsoncodec

import (
	"fmt"
	"reflect"

	"go.mongodb.org/mongo-driver/bson/bsonoptions"
	"go.mongodb.org/mongo-driver/bson/bsonrw"
	"go.mongodb.org/mongo-driver/bson/bsontype"
)

// StringCodec is the Codec used for struct values.
type StringCodec struct {
	DecodeObjectIDAsHex bool
}

var (
	defaultStringCodec = NewStringCodec()

	_ ValueCodec  = defaultStringCodec
	_ typeDecoder = defaultStringCodec
)

// NewStringCodec returns a StringCodec with options opts.
func NewStringCodec(opts ...*bsonoptions.StringCodecOptions) *StringCodec {
	stringOpt := bsonoptions.MergeStringCodecOptions(opts...)
	return &StringCodec{*stringOpt.DecodeObjectIDAsHex}
}

// EncodeValue is the ValueEncoder for string types.
func (sc *StringCodec) EncodeValue(ectx EncodeContext, vw bsonrw.ValueWriter, val reflect.Value) error {
	if val.Kind() != reflect.String {
		return ValueEncoderError{
			Name:     "StringEncodeValue",
			Kinds:    []reflect.Kind{reflect.String},
			Received: val,
		}
	}

	return vw.WriteString(val.String())
}

func (sc *StringCodec) decodeType(dc DecodeContext, vr bsonrw.ValueReader, t reflect.Type) (reflect.Value, error) {
	if t.Kind() != reflect.String {
		return emptyValue, ValueDecoderError{
			Name:     "StringDecodeValue",
			Kinds:    []reflect.Kind{reflect.String},
			Received: reflect.Zero(t),
		}
	}

	var str string
	var err error
	switch vr.Type() {
	case bsontype.String:
		str, err = vr.ReadString()
		if err != nil {
			return emptyValue, err
		}
	case bsontype.ObjectID:
		oid, err := vr.ReadObjectID()
		if err != nil {
			return emptyValue, err
		}
		if sc.DecodeObjectIDAsHex {
			str = oid.Hex()
		} else {
			byteArray := [12]byte(oid)
			str = string(byteArray[:])
		}
	case bsontype.Symbol:
		str, err = vr.ReadSymbol()
		if err != nil {
			return emptyValue, err
		}
	case bsontype.Binary:
		data, subtype, err := vr.ReadBinary()
		if err != nil {
			return emptyValue, err
		}
		if subtype != bsontype.BinaryGeneric && subtype != bsontype.BinaryBinaryOld {
			return emptyValue, decodeBinaryError{subtype: subtype, typeName: "string"}
		}
		str = string(data)
	case bsontype.Null:
		if err = vr.ReadNull(); err != nil {
			return emptyValue, err
		}
	case bsontype.Undefined:
		if err = vr.ReadUndefined(); err != nil {
			return emptyValue, err
		}
	default:
		return emptyValue, fmt.Errorf("cannot decode %v into a string type", vr.Type())
	}

	return reflect.ValueOf(str), nil
}

// DecodeValue is the ValueDecoder for string types.
func (sc *StringCodec) DecodeValue(dctx DecodeContext, vr bsonrw.ValueReader, val reflect.Value) error {
	if !val.CanSet() || val.Kind() != reflect.String {
		return ValueDecoderError{Name: "StringDecodeValue", Kinds: []reflect.Kind{reflect.String}, Received: val}
	}

	elem, err := sc.decodeType(dctx, vr, val.Type())
	if err != nil {
		return err
	}

	val.SetString(elem.String())
	return nil
}