1 files changed, 198 insertions, 0 deletions
diff --git a/vendor/github.com/nicksnyder/go-i18n/v2/i18n/localizer.go b/vendor/github.com/nicksnyder/go-i18n/v2/i18n/localizer.go
new file mode 100644
index 000000000..f9d516fa6
--- /dev/null
+++ b/vendor/github.com/nicksnyder/go-i18n/v2/i18n/localizer.go
@@ -0,0 +1,198 @@
+package i18n
+
+import (
+	"fmt"
+
+	"text/template"
+
+	"github.com/nicksnyder/go-i18n/v2/internal"
+	"github.com/nicksnyder/go-i18n/v2/internal/plural"
+	"golang.org/x/text/language"
+)
+
+// Localizer provides Localize and MustLocalize methods that return localized messages.
+type Localizer struct {
+	// bundle contains the messages that can be returned by the Localizer.
+	bundle *Bundle
+
+	// tags is the list of language tags that the Localizer checks
+	// in order when localizing a message.
+	tags []language.Tag
+}
+
+// NewLocalizer returns a new Localizer that looks up messages
+// in the bundle according to the language preferences in langs.
+// It can parse Accept-Language headers as defined in http://www.ietf.org/rfc/rfc2616.txt.
+func NewLocalizer(bundle *Bundle, langs ...string) *Localizer {
+	bundle.init()
+	return &Localizer{
+		bundle: bundle,
+		tags:   parseTags(langs),
+	}
+}
+
+func parseTags(langs []string) []language.Tag {
+	tags := []language.Tag{}
+	for _, lang := range langs {
+		t, _, err := language.ParseAcceptLanguage(lang)
+		if err != nil {
+			continue
+		}
+		tags = append(tags, t...)
+	}
+	return tags
+}
+
+// LocalizeConfig configures a call to the Localize method on Localizer.
+type LocalizeConfig struct {
+	// MessageID is the id of the message to lookup.
+	// This field is ignored if DefaultMessage is set.
+	MessageID string
+
+	// TemplateData is the data passed when executing the message's template.
+	// If TemplateData is nil and PluralCount is not nil, then the message template
+	// will be executed with data that contains the plural count.
+	TemplateData interface{}
+
+	// PluralCount determines which plural form of the message is used.
+	PluralCount interface{}
+
+	// DefaultMessage is used if the message is not found in any message files.
+	DefaultMessage *Message
+
+	// Funcs is used to extend the Go template engines built in functions
+	Funcs template.FuncMap
+}
+
+type invalidPluralCountErr struct {
+	messageID   string
+	pluralCount interface{}
+	err         error
+}
+
+func (e *invalidPluralCountErr) Error() string {
+	return fmt.Sprintf("invalid plural count %#v for message id %q: %s", e.pluralCount, e.messageID, e.err)
+}
+
+type messageNotFoundErr struct {
+	messageID string
+}
+
+func (e *messageNotFoundErr) Error() string {
+	return fmt.Sprintf("message %q not found", e.messageID)
+}
+
+type pluralizeErr struct {
+	messageID string
+	tag       language.Tag
+}
+
+func (e *pluralizeErr) Error() string {
+	return fmt.Sprintf("unable to pluralize %q because there no plural rule for %q", e.messageID, e.tag)
+}
+
+// Localize returns a localized message.
+func (l *Localizer) Localize(lc *LocalizeConfig) (string, error) {
+	messageID := lc.MessageID
+	if lc.DefaultMessage != nil {
+		messageID = lc.DefaultMessage.ID
+	}
+
+	var operands *plural.Operands
+	templateData := lc.TemplateData
+	if lc.PluralCount != nil {
+		var err error
+		operands, err = plural.NewOperands(lc.PluralCount)
+		if err != nil {
+			return "", &invalidPluralCountErr{messageID: messageID, pluralCount: lc.PluralCount, err: err}
+		}
+		if templateData == nil {
+			templateData = map[string]interface{}{
+				"PluralCount": lc.PluralCount,
+			}
+		}
+	}
+	tag, template := l.getTemplate(messageID, lc.DefaultMessage)
+	if template == nil {
+		return "", &messageNotFoundErr{messageID: messageID}
+	}
+	pluralForm := l.pluralForm(tag, operands)
+	if pluralForm == plural.Invalid {
+		return "", &pluralizeErr{messageID: messageID, tag: tag}
+	}
+	return template.Execute(pluralForm, templateData, lc.Funcs)
+}
+
+func (l *Localizer) getTemplate(id string, defaultMessage *Message) (language.Tag, *internal.MessageTemplate) {
+	// Fast path.
+	// Optimistically assume this message id is defined in each language.
+	fastTag, template := l.matchTemplate(id, l.bundle.matcher, l.bundle.tags)
+	if template != nil {
+		return fastTag, template
+	}
+	if fastTag == l.bundle.DefaultLanguage {
+		if defaultMessage == nil {
+			return fastTag, nil
+		}
+		return fastTag, internal.NewMessageTemplate(defaultMessage)
+	}
+	if len(l.bundle.tags) > 1 {
+		// Slow path.
+		// We didn't find a translation for the tag suggested by the default matcher
+		// so we need to create a new matcher that contains only the tags in the bundle
+		// that have this message.
+		foundTags := make([]language.Tag, 0, len(l.bundle.messageTemplates))
+		if l.bundle.DefaultLanguage != fastTag {
+			foundTags = append(foundTags, l.bundle.DefaultLanguage)
+		}
+		for t, templates := range l.bundle.messageTemplates {
+			if t == fastTag {
+				// We already tried this tag in the fast path
+				continue
+			}
+			template := templates[id]
+			if template == nil || template.Other == "" {
+				continue
+			}
+			foundTags = append(foundTags, t)
+		}
+		tag, template := l.matchTemplate(id, language.NewMatcher(foundTags), foundTags)
+		if template != nil {
+			return tag, template
+		}
+	}
+	if defaultMessage == nil {
+		return l.bundle.DefaultLanguage, nil
+	}
+	return l.bundle.DefaultLanguage, internal.NewMessageTemplate(defaultMessage)
+}
+
+func (l *Localizer) matchTemplate(id string, matcher language.Matcher, tags []language.Tag) (language.Tag, *internal.MessageTemplate) {
+	_, i, _ := matcher.Match(l.tags...)
+	tag := tags[i]
+	templates := l.bundle.messageTemplates[tag]
+	if templates != nil && templates[id] != nil {
+		return tag, templates[id]
+	}
+	return tag, nil
+}
+
+func (l *Localizer) pluralForm(tag language.Tag, operands *plural.Operands) plural.Form {
+	if operands == nil {
+		return plural.Other
+	}
+	pluralRule := l.bundle.pluralRules.Rule(tag)
+	if pluralRule == nil {
+		return plural.Invalid
+	}
+	return pluralRule.PluralFormFunc(operands)
+}
+
+// MustLocalize is similar to Localize, except it panics if an error happens.
+func (l *Localizer) MustLocalize(lc *LocalizeConfig) string {
+	localized, err := l.Localize(lc)
+	if err != nil {
+		panic(err)
+	}
+	return localized
+}