gotosocial/vendor/github.com/ncruces/go-sqlite3/time.go

357 lines
9.1 KiB
Go

package sqlite3
import (
"math"
"strconv"
"strings"
"time"
"github.com/ncruces/go-sqlite3/internal/util"
"github.com/ncruces/julianday"
)
// TimeFormat specifies how to encode/decode time values.
//
// See the documentation for the [TimeFormatDefault] constant
// for formats recognized by SQLite.
//
// https://sqlite.org/lang_datefunc.html
type TimeFormat string
// TimeFormats recognized by SQLite to encode/decode time values.
//
// https://sqlite.org/lang_datefunc.html#time_values
const (
TimeFormatDefault TimeFormat = "" // time.RFC3339Nano
// Text formats
TimeFormat1 TimeFormat = "2006-01-02"
TimeFormat2 TimeFormat = "2006-01-02 15:04"
TimeFormat3 TimeFormat = "2006-01-02 15:04:05"
TimeFormat4 TimeFormat = "2006-01-02 15:04:05.000"
TimeFormat5 TimeFormat = "2006-01-02T15:04"
TimeFormat6 TimeFormat = "2006-01-02T15:04:05"
TimeFormat7 TimeFormat = "2006-01-02T15:04:05.000"
TimeFormat8 TimeFormat = "15:04"
TimeFormat9 TimeFormat = "15:04:05"
TimeFormat10 TimeFormat = "15:04:05.000"
TimeFormat2TZ = TimeFormat2 + "Z07:00"
TimeFormat3TZ = TimeFormat3 + "Z07:00"
TimeFormat4TZ = TimeFormat4 + "Z07:00"
TimeFormat5TZ = TimeFormat5 + "Z07:00"
TimeFormat6TZ = TimeFormat6 + "Z07:00"
TimeFormat7TZ = TimeFormat7 + "Z07:00"
TimeFormat8TZ = TimeFormat8 + "Z07:00"
TimeFormat9TZ = TimeFormat9 + "Z07:00"
TimeFormat10TZ = TimeFormat10 + "Z07:00"
// Numeric formats
TimeFormatJulianDay TimeFormat = "julianday"
TimeFormatUnix TimeFormat = "unixepoch"
TimeFormatUnixFrac TimeFormat = "unixepoch_frac"
TimeFormatUnixMilli TimeFormat = "unixepoch_milli" // not an SQLite format
TimeFormatUnixMicro TimeFormat = "unixepoch_micro" // not an SQLite format
TimeFormatUnixNano TimeFormat = "unixepoch_nano" // not an SQLite format
// Auto
TimeFormatAuto TimeFormat = "auto"
)
// Encode encodes a time value using this format.
//
// [TimeFormatDefault] and [TimeFormatAuto] encode using [time.RFC3339Nano],
// with nanosecond accuracy, and preserving any timezone offset.
//
// This is the format used by the [database/sql] driver:
// [database/sql.Row.Scan] will decode as [time.Time]
// values encoded with [time.RFC3339Nano].
//
// Time values encoded with [time.RFC3339Nano] cannot be sorted as strings
// to produce a time-ordered sequence.
//
// Assuming that the time zones of the time values are the same (e.g., all in UTC),
// and expressed using the same string (e.g., all "Z" or all "+00:00"),
// use the TIME [collating sequence] to produce a time-ordered sequence.
//
// Otherwise, use [TimeFormat7] for time-ordered encoding.
//
// Formats [TimeFormat1] through [TimeFormat10]
// convert time values to UTC before encoding.
//
// Returns a string for the text formats,
// a float64 for [TimeFormatJulianDay] and [TimeFormatUnixFrac],
// or an int64 for the other numeric formats.
//
// https://sqlite.org/lang_datefunc.html
//
// [collating sequence]: https://sqlite.org/datatype3.html#collating_sequences
func (f TimeFormat) Encode(t time.Time) any {
switch f {
// Numeric formats
case TimeFormatJulianDay:
return julianday.Float(t)
case TimeFormatUnix:
return t.Unix()
case TimeFormatUnixFrac:
return float64(t.Unix()) + float64(t.Nanosecond())*1e-9
case TimeFormatUnixMilli:
return t.UnixMilli()
case TimeFormatUnixMicro:
return t.UnixMicro()
case TimeFormatUnixNano:
return t.UnixNano()
// Special formats.
case TimeFormatDefault, TimeFormatAuto:
f = time.RFC3339Nano
// SQLite assumes UTC if unspecified.
case
TimeFormat1, TimeFormat2,
TimeFormat3, TimeFormat4,
TimeFormat5, TimeFormat6,
TimeFormat7, TimeFormat8,
TimeFormat9, TimeFormat10:
t = t.UTC()
}
return t.Format(string(f))
}
// Decode decodes a time value using this format.
//
// The time value can be a string, an int64, or a float64.
//
// Formats [TimeFormat8] through [TimeFormat10]
// (and [TimeFormat8TZ] through [TimeFormat10TZ])
// assume a date of 2000-01-01.
//
// The timezone indicator and fractional seconds are always optional
// for formats [TimeFormat2] through [TimeFormat10]
// (and [TimeFormat2TZ] through [TimeFormat10TZ]).
//
// [TimeFormatAuto] implements (and extends) the SQLite auto modifier.
// Julian day numbers are safe to use for historical dates,
// from 4712BC through 9999AD.
// Unix timestamps (expressed in seconds, milliseconds, microseconds, or nanoseconds)
// are safe to use for current events, from at least 1980 through at least 2260.
// Unix timestamps before 1980 and after 9999 may be misinterpreted as julian day numbers,
// or have the wrong time unit.
//
// https://sqlite.org/lang_datefunc.html
func (f TimeFormat) Decode(v any) (time.Time, error) {
if t, ok := v.(time.Time); ok {
return t, nil
}
switch f {
// Numeric formats.
case TimeFormatJulianDay:
switch v := v.(type) {
case string:
return julianday.Parse(v)
case float64:
return julianday.FloatTime(v), nil
case int64:
return julianday.Time(v, 0), nil
default:
return time.Time{}, util.TimeErr
}
case TimeFormatUnix, TimeFormatUnixFrac:
if s, ok := v.(string); ok {
f, err := strconv.ParseFloat(s, 64)
if err != nil {
return time.Time{}, err
}
v = f
}
switch v := v.(type) {
case float64:
sec, frac := math.Modf(v)
nsec := math.Floor(frac * 1e9)
return time.Unix(int64(sec), int64(nsec)).UTC(), nil
case int64:
return time.Unix(v, 0).UTC(), nil
default:
return time.Time{}, util.TimeErr
}
case TimeFormatUnixMilli:
if s, ok := v.(string); ok {
i, err := strconv.ParseInt(s, 10, 64)
if err != nil {
return time.Time{}, err
}
v = i
}
switch v := v.(type) {
case float64:
return time.UnixMilli(int64(math.Floor(v))).UTC(), nil
case int64:
return time.UnixMilli(v).UTC(), nil
default:
return time.Time{}, util.TimeErr
}
case TimeFormatUnixMicro:
if s, ok := v.(string); ok {
i, err := strconv.ParseInt(s, 10, 64)
if err != nil {
return time.Time{}, err
}
v = i
}
switch v := v.(type) {
case float64:
return time.UnixMicro(int64(math.Floor(v))).UTC(), nil
case int64:
return time.UnixMicro(v).UTC(), nil
default:
return time.Time{}, util.TimeErr
}
case TimeFormatUnixNano:
if s, ok := v.(string); ok {
i, err := strconv.ParseInt(s, 10, 64)
if err != nil {
return time.Time{}, util.TimeErr
}
v = i
}
switch v := v.(type) {
case float64:
return time.Unix(0, int64(math.Floor(v))).UTC(), nil
case int64:
return time.Unix(0, v).UTC(), nil
default:
return time.Time{}, util.TimeErr
}
// Special formats.
case TimeFormatAuto:
switch s := v.(type) {
case string:
i, err := strconv.ParseInt(s, 10, 64)
if err == nil {
v = i
break
}
f, err := strconv.ParseFloat(s, 64)
if err == nil {
v = f
break
}
dates := []TimeFormat{
TimeFormat9, TimeFormat8,
TimeFormat6, TimeFormat5,
TimeFormat3, TimeFormat2, TimeFormat1,
}
for _, f := range dates {
t, err := f.Decode(s)
if err == nil {
return t, nil
}
}
}
switch v := v.(type) {
case float64:
if 0 <= v && v < 5373484.5 {
return TimeFormatJulianDay.Decode(v)
}
if v < 253402300800 {
return TimeFormatUnixFrac.Decode(v)
}
if v < 253402300800_000 {
return TimeFormatUnixMilli.Decode(v)
}
if v < 253402300800_000000 {
return TimeFormatUnixMicro.Decode(v)
}
return TimeFormatUnixNano.Decode(v)
case int64:
if 0 <= v && v < 5373485 {
return TimeFormatJulianDay.Decode(v)
}
if v < 253402300800 {
return TimeFormatUnixFrac.Decode(v)
}
if v < 253402300800_000 {
return TimeFormatUnixMilli.Decode(v)
}
if v < 253402300800_000000 {
return TimeFormatUnixMicro.Decode(v)
}
return TimeFormatUnixNano.Decode(v)
default:
return time.Time{}, util.TimeErr
}
case
TimeFormat2, TimeFormat2TZ,
TimeFormat3, TimeFormat3TZ,
TimeFormat4, TimeFormat4TZ,
TimeFormat5, TimeFormat5TZ,
TimeFormat6, TimeFormat6TZ,
TimeFormat7, TimeFormat7TZ:
s, ok := v.(string)
if !ok {
return time.Time{}, util.TimeErr
}
return f.parseRelaxed(s)
case
TimeFormat8, TimeFormat8TZ,
TimeFormat9, TimeFormat9TZ,
TimeFormat10, TimeFormat10TZ:
s, ok := v.(string)
if !ok {
return time.Time{}, util.TimeErr
}
t, err := f.parseRelaxed(s)
if err != nil {
return time.Time{}, err
}
return t.AddDate(2000, 0, 0), nil
default:
s, ok := v.(string)
if !ok {
return time.Time{}, util.TimeErr
}
if f == "" {
f = time.RFC3339Nano
}
return time.Parse(string(f), s)
}
}
func (f TimeFormat) parseRelaxed(s string) (time.Time, error) {
fs := string(f)
fs = strings.TrimSuffix(fs, "Z07:00")
fs = strings.TrimSuffix(fs, ".000")
t, err := time.Parse(fs+"Z07:00", s)
if err != nil {
return time.Parse(fs, s)
}
return t, nil
}
// Scanner returns a [database/sql.Scanner] that can be used as an argument to
// [database/sql.Row.Scan] and similar methods to
// decode a time value into dest using this format.
func (f TimeFormat) Scanner(dest *time.Time) interface{ Scan(any) error } {
return timeScanner{dest, f}
}
type timeScanner struct {
*time.Time
TimeFormat
}
func (s timeScanner) Scan(src any) error {
var ok bool
var err error
if *s.Time, ok = src.(time.Time); !ok {
*s.Time, err = s.Decode(src)
}
return err
}