New Marshal functions for VAST and VMAP

vmap/encoder_fast.go

@@ -0,0 +1,398 @@
+package vmap
+
+import (
+	"strconv"
+)
+
+// MarshalVmap marshals a VMAP to XML, producing output identical to encoding/xml.Marshal.
+func MarshalVmap(v *VMAP) ([]byte, error) {
+	buf := make([]byte, 0, 8192)
+	buf = appendVMAP(buf, v)
+	return buf, nil
+}
+
+// MarshalVast marshals a VAST to XML, producing output identical to encoding/xml.Marshal.
+func MarshalVast(v *VAST) ([]byte, error) {
+	buf := make([]byte, 0, 4096)
+	buf = appendVAST(buf, v)
+	return buf, nil
+}
+
+// --- escape helpers ---
+
+// escText escapes text content, matching encoding/xml.EscapeText.
+func escText(buf []byte, s string) []byte {
+	last := 0
+	for i := 0; i < len(s); i++ {
+		var esc string
+		switch s[i] {
+		case '&':
+			esc = "&amp;"
+		case '<':
+			esc = "&lt;"
+		case '>':
+			esc = "&gt;"
+		case '"':
+			esc = "&#34;"
+		case '\t':
+			esc = "&#x9;"
+		case '\n':
+			esc = "&#xA;"
+		case '\r':
+			esc = "&#xD;"
+		default:
+			continue
+		}
+		buf = append(buf, s[last:i]...)
+		buf = append(buf, esc...)
+		last = i + 1
+	}
+	return append(buf, s[last:]...)
+}
+
+// escAttr escapes attribute values, matching encoding/xml attribute escaping.
+func escAttr(buf []byte, s string) []byte {
+	last := 0
+	for i := 0; i < len(s); i++ {
+		var esc string
+		switch s[i] {
+		case '&':
+			esc = "&amp;"
+		case '<':
+			esc = "&lt;"
+		case '>':
+			esc = "&gt;"
+		case '"':
+			esc = "&#34;"
+		case '\t':
+			esc = "&#x9;"
+		case '\n':
+			esc = "&#xA;"
+		case '\r':
+			esc = "&#xD;"
+		default:
+			continue
+		}
+		buf = append(buf, s[last:i]...)
+		buf = append(buf, esc...)
+		last = i + 1
+	}
+	return append(buf, s[last:]...)
+}
+
+// --- duration / time offset helpers (allocation-free) ---
+
+func append2dig(buf []byte, n int) []byte {
+	return append(buf, byte('0'+n/10), byte('0'+n%10))
+}
+
+func append3dig(buf []byte, n int) []byte {
+	return append(buf, byte('0'+n/100), byte('0'+(n/10)%10), byte('0'+n%10))
+}
+
+func appendDuration(buf []byte, d Duration) []byte {
+	dur := d.Duration
+	if dur == 0 {
+		return append(buf, "00:00:00"...)
+	}
+	h := int(dur.Hours())
+	m := int(dur.Minutes()) % 60
+	s := int(dur.Seconds()) % 60
+	ms := int(dur.Milliseconds()) % 1000
+	buf = append2dig(buf, h)
+	buf = append(buf, ':')
+	buf = append2dig(buf, m)
+	buf = append(buf, ':')
+	buf = append2dig(buf, s)
+	if ms > 0 {
+		buf = append(buf, '.')
+		buf = append3dig(buf, ms)
+	}
+	return buf
+}
+
+func appendTimeOffset(buf []byte, to TimeOffset) []byte {
+	if to.Duration != nil {
+		return appendDuration(buf, *to.Duration)
+	}
+	if to.Position != 0 {
+		buf = append(buf, '#')
+		return strconv.AppendInt(buf, int64(to.Position), 10)
+	}
+	if to.Percent != 0 {
+		buf = strconv.AppendFloat(buf, float64(to.Percent*100), 'f', 6, 32)
+		return append(buf, '%')
+	}
+	return buf
+}
+
+// --- struct encoders ---
+// Field and attribute order matches encoding/xml.Marshal exactly.
+
+func appendVMAP(buf []byte, v *VMAP) []byte {
+	// XMLName tag is xml:"VMAP" (name only) — xml.Marshal does not output xmlns
+	buf = append(buf, `<VMAP vmap="`...)
+	buf = escAttr(buf, v.Vmap)
+	buf = append(buf, `" version="`...)
+	buf = escAttr(buf, v.Version)
+	buf = append(buf, '"', '>')
+
+	// chardata (Text field, before child elements, matching xml.Marshal field order)
+	buf = escText(buf, v.Text)
+
+	for i := range v.AdBreaks {
+		buf = appendAdBreak(buf, &v.AdBreaks[i])
+	}
+	buf = append(buf, "</VMAP>"...)
+	return buf
+}
+
+func appendAdBreak(buf []byte, ab *AdBreak) []byte {
+	// attrs: breakId, breakType, timeOffset
+	buf = append(buf, `<AdBreak breakId="`...)
+	buf = escAttr(buf, ab.Id)
+	buf = append(buf, `" breakType="`...)
+	buf = escAttr(buf, ab.BreakType)
+	buf = append(buf, `" timeOffset="`...)
+	buf = appendTimeOffset(buf, ab.TimeOffset)
+	buf = append(buf, '"', '>')
+
+	// child elements in field order: AdSource, TrackingEvents
+	if ab.AdSource != nil {
+		buf = appendAdSource(buf, ab.AdSource)
+	}
+	// Wrapper always emitted for nested path xml:"TrackingEvents>Tracking"
+	buf = append(buf, "<TrackingEvents>"...)
+	for i := range ab.TrackingEvents {
+		buf = appendTracking(buf, &ab.TrackingEvents[i])
+	}
+	buf = append(buf, "</TrackingEvents>"...)
+	buf = append(buf, "</AdBreak>"...)
+	return buf
+}
+
+func appendAdSource(buf []byte, as *AdSource) []byte {
+	buf = append(buf, "<AdSource>"...)
+	if as.VASTData != nil {
+		buf = append(buf, "<VASTAdData>"...)
+		if as.VASTData.VAST != nil {
+			buf = appendVAST(buf, as.VASTData.VAST)
+		}
+		buf = append(buf, "</VASTAdData>"...)
+	}
+	buf = append(buf, "</AdSource>"...)
+	return buf
+}
+
+func appendVAST(buf []byte, v *VAST) []byte {
+	// attrs: xsi, noNamespaceSchemaLocation, version
+	buf = append(buf, `<VAST xsi="`...)
+	buf = escAttr(buf, v.Xsi)
+	buf = append(buf, `" noNamespaceSchemaLocation="`...)
+	buf = escAttr(buf, v.NoNamespaceSchemaLocation)
+	buf = append(buf, `" version="`...)
+	buf = escAttr(buf, v.Version)
+	buf = append(buf, '"', '>')
+
+	// chardata
+	buf = escText(buf, v.Text)
+
+	for i := range v.Ad {
+		buf = appendAd(buf, &v.Ad[i])
+	}
+	buf = append(buf, "</VAST>"...)
+	return buf
+}
+
+func appendAd(buf []byte, ad *Ad) []byte {
+	buf = append(buf, `<Ad id="`...)
+	buf = escAttr(buf, ad.Id)
+	buf = append(buf, `" sequence="`...)
+	buf = strconv.AppendInt(buf, int64(ad.Sequence), 10)
+	buf = append(buf, '"', '>')
+
+	if ad.InLine != nil {
+		buf = appendInLine(buf, ad.InLine)
+	}
+	buf = append(buf, "</Ad>"...)
+	return buf
+}
+
+func appendInLine(buf []byte, il *InLine) []byte {
+	buf = append(buf, "<InLine>"...)
+
+	// field order: AdSystem, AdTitle, Impression, Creatives, Extensions, Error
+	buf = append(buf, "<AdSystem>"...)
+	buf = escText(buf, il.AdSystem)
+	buf = append(buf, "</AdSystem>"...)
+
+	buf = append(buf, "<AdTitle>"...)
+	buf = escText(buf, il.AdTitle)
+	buf = append(buf, "</AdTitle>"...)
+
+	for i := range il.Impression {
+		buf = appendImpression(buf, &il.Impression[i])
+	}
+
+	// Wrappers always emitted for nested paths
+	buf = append(buf, "<Creatives>"...)
+	for i := range il.Creatives {
+		buf = appendCreative(buf, &il.Creatives[i])
+	}
+	buf = append(buf, "</Creatives>"...)
+
+	buf = append(buf, "<Extensions>"...)
+	for i := range il.Extensions {
+		buf = appendExtension(buf, &il.Extensions[i])
+	}
+	buf = append(buf, "</Extensions>"...)
+
+	if il.Error != nil {
+		buf = append(buf, "<Error>"...)
+		buf = escText(buf, il.Error.Value)
+		buf = append(buf, "</Error>"...)
+	}
+
+	buf = append(buf, "</InLine>"...)
+	return buf
+}
+
+func appendImpression(buf []byte, imp *Impression) []byte {
+	buf = append(buf, `<Impression id="`...)
+	buf = escAttr(buf, imp.Id)
+	buf = append(buf, '"', '>')
+	buf = escText(buf, imp.Text)
+	buf = append(buf, "</Impression>"...)
+	return buf
+}
+
+func appendCreative(buf []byte, c *Creative) []byte {
+	buf = append(buf, `<Creative id="`...)
+	buf = escAttr(buf, c.Id)
+	buf = append(buf, `" adId="`...)
+	buf = escAttr(buf, c.AdId)
+	buf = append(buf, '"', '>')
+
+	if c.UniversalAdId != nil {
+		buf = append(buf, `<UniversalAdId idRegistry="`...)
+		buf = escAttr(buf, c.UniversalAdId.IdRegistry)
+		buf = append(buf, '"', '>')
+		buf = escText(buf, c.UniversalAdId.Id)
+		buf = append(buf, "</UniversalAdId>"...)
+	}
+
+	if c.Linear != nil {
+		buf = appendLinear(buf, c.Linear)
+	}
+
+	buf = append(buf, "</Creative>"...)
+	return buf
+}
+
+func appendLinear(buf []byte, l *Linear) []byte {
+	buf = append(buf, "<Linear>"...)
+
+	// Duration
+	buf = append(buf, "<Duration>"...)
+	buf = appendDuration(buf, l.Duration)
+	buf = append(buf, "</Duration>"...)
+
+	// Wrappers always emitted for nested paths
+	buf = append(buf, "<TrackingEvents>"...)
+	for i := range l.TrackingEvents {
+		buf = appendTracking(buf, &l.TrackingEvents[i])
+	}
+	buf = append(buf, "</TrackingEvents>"...)
+
+	buf = append(buf, "<MediaFiles>"...)
+	for i := range l.MediaFiles {
+		buf = appendMediaFile(buf, &l.MediaFiles[i])
+	}
+	buf = append(buf, "</MediaFiles>"...)
+
+	// VideoClicks (shared wrapper for ClickThrough, ClickTracking, CustomClick)
+	buf = append(buf, "<VideoClicks>"...)
+	if l.ClickThrough != nil {
+		buf = append(buf, `<ClickThrough id="`...)
+		buf = escAttr(buf, l.ClickThrough.Id)
+		buf = append(buf, '"', '>')
+		buf = escText(buf, l.ClickThrough.Text)
+		buf = append(buf, "</ClickThrough>"...)
+	}
+	for i := range l.ClickTracking {
+		buf = append(buf, `<ClickTracking id="`...)
+		buf = escAttr(buf, l.ClickTracking[i].Id)
+		buf = append(buf, '"', '>')
+		buf = escText(buf, l.ClickTracking[i].Text)
+		buf = append(buf, "</ClickTracking>"...)
+	}
+	for i := range l.CustomClick {
+		buf = append(buf, `<CustomClick id="`...)
+		buf = escAttr(buf, l.CustomClick[i].Id)
+		buf = append(buf, '"', '>')
+		buf = escText(buf, l.CustomClick[i].Text)
+		buf = append(buf, "</CustomClick>"...)
+	}
+	buf = append(buf, "</VideoClicks>"...)
+
+	buf = append(buf, "</Linear>"...)
+	return buf
+}
+
+func appendTracking(buf []byte, t *TrackingEvent) []byte {
+	buf = append(buf, `<Tracking event="`...)
+	buf = escAttr(buf, t.Event)
+	buf = append(buf, '"', '>')
+	buf = escText(buf, t.Text)
+	buf = append(buf, "</Tracking>"...)
+	return buf
+}
+
+func appendMediaFile(buf []byte, m *MediaFile) []byte {
+	// attr order: bitrate, width, height, delivery, type, codec
+	buf = append(buf, `<MediaFile bitrate="`...)
+	buf = strconv.AppendInt(buf, int64(m.Bitrate), 10)
+	buf = append(buf, `" width="`...)
+	buf = strconv.AppendInt(buf, int64(m.Width), 10)
+	buf = append(buf, `" height="`...)
+	buf = strconv.AppendInt(buf, int64(m.Height), 10)
+	buf = append(buf, `" delivery="`...)
+	buf = escAttr(buf, m.Delivery)
+	buf = append(buf, `" type="`...)
+	buf = escAttr(buf, m.MediaType)
+	buf = append(buf, `" codec="`...)
+	buf = escAttr(buf, m.Codec)
+	buf = append(buf, '"', '>')
+	buf = escText(buf, m.Text)
+	buf = append(buf, "</MediaFile>"...)
+	return buf
+}
+
+func appendExtension(buf []byte, ext *Extension) []byte {
+	buf = append(buf, `<Extension type="`...)
+	buf = escAttr(buf, ext.ExtensionType)
+	buf = append(buf, '"', '>')
+
+	buf = append(buf, "<CreativeParameters>"...)
+	for i := range ext.CreativeParameters {
+		buf = appendCreativeParameter(buf, &ext.CreativeParameters[i])
+	}
+	buf = append(buf, "</CreativeParameters>"...)
+
+	buf = append(buf, "</Extension>"...)
+	return buf
+}
+
+func appendCreativeParameter(buf []byte, cp *CreativeParameter) []byte {
+	// attr order: creativeId, name, type (Value is chardata)
+	buf = append(buf, `<CreativeParameter creativeId="`...)
+	buf = escAttr(buf, cp.CreativeId)
+	buf = append(buf, `" name="`...)
+	buf = escAttr(buf, cp.Name)
+	buf = append(buf, `" type="`...)
+	buf = escAttr(buf, cp.CreativeParameterType)
+	buf = append(buf, '"', '>')
+	buf = escText(buf, cp.Value)
+	buf = append(buf, "</CreativeParameter>"...)
+	return buf
+}