mc-webserver/pageHandler/utils/content-range-value.go
2023-08-13 20:19:47 +01:00

79 lines
2.1 KiB
Go

package utils
import (
"strconv"
"strings"
)
type ContentRangeValue struct {
Start, Length int64
}
func (rstrc ContentRangeValue) ToField(maxLength int64) string {
return "bytes " + strconv.FormatInt(rstrc.Start, 10) + "-" + strconv.FormatInt(rstrc.Start+rstrc.Length-1, 10) + "/" + strconv.FormatInt(maxLength, 10)
}
func GetRanges(rangeStringIn string, maxLength int64) []ContentRangeValue {
actualRangeString := strings.TrimPrefix(rangeStringIn, "bytes=")
if strings.ContainsAny(actualRangeString, ",") {
seperated := strings.Split(actualRangeString, ",")
toReturn := make([]ContentRangeValue, len(seperated))
pos := 0
for _, s := range seperated {
if cRange, ok := GetRange(s, maxLength); ok {
toReturn[pos] = cRange
pos += 1
}
}
if pos == 0 {
return nil
}
return toReturn[:pos]
}
if cRange, ok := GetRange(actualRangeString, maxLength); ok {
return []ContentRangeValue{cRange}
}
return nil
}
func GetRange(rangePartIn string, maxLength int64) (ContentRangeValue, bool) {
before, after, done := strings.Cut(rangePartIn, "-")
before = strings.Trim(before, " ")
after = strings.Trim(after, " ")
if !done {
return ContentRangeValue{}, false
}
var parsedAfter, parsedBefore int64 = -1, -1
if after != "" {
if parsed, err := strconv.ParseInt(after, 10, 64); err == nil {
parsedAfter = parsed
} else {
return ContentRangeValue{}, false
}
}
if before != "" {
if parsed, err := strconv.ParseInt(before, 10, 64); err == nil {
parsedBefore = parsed
} else {
return ContentRangeValue{}, false
}
}
if parsedBefore >= 0 && parsedAfter > parsedBefore && parsedAfter < maxLength {
return ContentRangeValue{
Start: parsedBefore,
Length: parsedAfter - parsedBefore + 1,
}, true
} else if parsedAfter < 0 && parsedBefore >= 0 && parsedBefore < maxLength {
return ContentRangeValue{
Start: parsedBefore,
Length: maxLength - parsedBefore,
}, true
} else if parsedBefore < 0 && parsedAfter >= 1 && maxLength-parsedAfter >= 0 {
return ContentRangeValue{
Start: maxLength - parsedAfter,
Length: parsedAfter,
}, true
}
return ContentRangeValue{}, false
}