podman

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// Copyright (C) MongoDB, Inc. 2017-present.
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//
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// Licensed under the Apache License, Version 2.0 (the "License"); you may
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// not use this file except in compliance with the License. You may obtain
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// a copy of the License at http://www.apache.org/licenses/LICENSE-2.0
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//
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// Based on gopkg.in/mgo.v2/bson by Gustavo Niemeyer
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// See THIRD-PARTY-NOTICES for original license terms.
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package primitive
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import (
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	"crypto/rand"
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	"encoding"
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	"encoding/binary"
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	"encoding/hex"
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	"encoding/json"
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	"errors"
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	"fmt"
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	"io"
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	"sync/atomic"
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	"time"
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)
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// ErrInvalidHex indicates that a hex string cannot be converted to an ObjectID.
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var ErrInvalidHex = errors.New("the provided hex string is not a valid ObjectID")
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// ObjectID is the BSON ObjectID type.
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type ObjectID [12]byte
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// NilObjectID is the zero value for ObjectID.
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var NilObjectID ObjectID
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var objectIDCounter = readRandomUint32()
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var processUnique = processUniqueBytes()
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var _ encoding.TextMarshaler = ObjectID{}
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var _ encoding.TextUnmarshaler = &ObjectID{}
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// NewObjectID generates a new ObjectID.
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func NewObjectID() ObjectID {
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	return NewObjectIDFromTimestamp(time.Now())
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}
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// NewObjectIDFromTimestamp generates a new ObjectID based on the given time.
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func NewObjectIDFromTimestamp(timestamp time.Time) ObjectID {
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	var b [12]byte
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	binary.BigEndian.PutUint32(b[0:4], uint32(timestamp.Unix()))
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	copy(b[4:9], processUnique[:])
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	putUint24(b[9:12], atomic.AddUint32(&objectIDCounter, 1))
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	return b
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}
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// Timestamp extracts the time part of the ObjectId.
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func (id ObjectID) Timestamp() time.Time {
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	unixSecs := binary.BigEndian.Uint32(id[0:4])
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	return time.Unix(int64(unixSecs), 0).UTC()
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}
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// Hex returns the hex encoding of the ObjectID as a string.
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func (id ObjectID) Hex() string {
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	var buf [24]byte
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	hex.Encode(buf[:], id[:])
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	return string(buf[:])
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}
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func (id ObjectID) String() string {
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	return fmt.Sprintf("ObjectID(%q)", id.Hex())
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}
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// IsZero returns true if id is the empty ObjectID.
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func (id ObjectID) IsZero() bool {
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	return id == NilObjectID
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}
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// ObjectIDFromHex creates a new ObjectID from a hex string. It returns an error if the hex string is not a
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// valid ObjectID.
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func ObjectIDFromHex(s string) (ObjectID, error) {
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	if len(s) != 24 {
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		return NilObjectID, ErrInvalidHex
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	}
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	b, err := hex.DecodeString(s)
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	if err != nil {
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		return NilObjectID, err
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	}
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	var oid [12]byte
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	copy(oid[:], b)
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	return oid, nil
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}
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// IsValidObjectID returns true if the provided hex string represents a valid ObjectID and false if not.
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func IsValidObjectID(s string) bool {
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	_, err := ObjectIDFromHex(s)
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	return err == nil
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}
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// MarshalText returns the ObjectID as UTF-8-encoded text. Implementing this allows us to use ObjectID
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// as a map key when marshalling JSON. See https://pkg.go.dev/encoding#TextMarshaler
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func (id ObjectID) MarshalText() ([]byte, error) {
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	return []byte(id.Hex()), nil
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}
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// UnmarshalText populates the byte slice with the ObjectID. Implementing this allows us to use ObjectID
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// as a map key when unmarshalling JSON. See https://pkg.go.dev/encoding#TextUnmarshaler
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func (id *ObjectID) UnmarshalText(b []byte) error {
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	oid, err := ObjectIDFromHex(string(b))
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	if err != nil {
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		return err
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	}
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	*id = oid
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	return nil
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}
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// MarshalJSON returns the ObjectID as a string
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func (id ObjectID) MarshalJSON() ([]byte, error) {
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	return json.Marshal(id.Hex())
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}
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// UnmarshalJSON populates the byte slice with the ObjectID. If the byte slice is 24 bytes long, it
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// will be populated with the hex representation of the ObjectID. If the byte slice is twelve bytes
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// long, it will be populated with the BSON representation of the ObjectID. This method also accepts empty strings and
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// decodes them as NilObjectID. For any other inputs, an error will be returned.
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func (id *ObjectID) UnmarshalJSON(b []byte) error {
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	// Ignore "null" to keep parity with the standard library. Decoding a JSON null into a non-pointer ObjectID field
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	// will leave the field unchanged. For pointer values, encoding/json will set the pointer to nil and will not
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	// enter the UnmarshalJSON hook.
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	if string(b) == "null" {
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		return nil
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	}
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	var err error
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	switch len(b) {
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	case 12:
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		copy(id[:], b)
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	default:
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		// Extended JSON
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		var res interface{}
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		err := json.Unmarshal(b, &res)
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		if err != nil {
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			return err
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		}
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		str, ok := res.(string)
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		if !ok {
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			m, ok := res.(map[string]interface{})
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			if !ok {
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				return errors.New("not an extended JSON ObjectID")
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			}
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			oid, ok := m["$oid"]
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			if !ok {
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				return errors.New("not an extended JSON ObjectID")
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			}
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			str, ok = oid.(string)
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			if !ok {
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				return errors.New("not an extended JSON ObjectID")
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			}
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		}
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		// An empty string is not a valid ObjectID, but we treat it as a special value that decodes as NilObjectID.
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		if len(str) == 0 {
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			copy(id[:], NilObjectID[:])
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			return nil
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		}
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		if len(str) != 24 {
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			return fmt.Errorf("cannot unmarshal into an ObjectID, the length must be 24 but it is %d", len(str))
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		}
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		_, err = hex.Decode(id[:], []byte(str))
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		if err != nil {
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			return err
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		}
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	}
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	return err
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}
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func processUniqueBytes() [5]byte {
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	var b [5]byte
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	_, err := io.ReadFull(rand.Reader, b[:])
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	if err != nil {
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		panic(fmt.Errorf("cannot initialize objectid package with crypto.rand.Reader: %v", err))
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	}
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	return b
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}
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func readRandomUint32() uint32 {
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	var b [4]byte
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	_, err := io.ReadFull(rand.Reader, b[:])
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	if err != nil {
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		panic(fmt.Errorf("cannot initialize objectid package with crypto.rand.Reader: %v", err))
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	}
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	return (uint32(b[0]) << 0) | (uint32(b[1]) << 8) | (uint32(b[2]) << 16) | (uint32(b[3]) << 24)
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}
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func putUint24(b []byte, v uint32) {
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	b[0] = byte(v >> 16)
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	b[1] = byte(v >> 8)
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	b[2] = byte(v)
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}
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