rewrite using IoC and DI

model/media.go

@@ -0,0 +1,54 @@
+package model
+
+import (
+	"AynaLivePlayer/liveclient"
+	"github.com/jinzhu/copier"
+)
+
+type Picture struct {
+	Url  string
+	Data []byte
+}
+
+func (p Picture) Exists() bool {
+	return p.Url != "" || p.Data != nil
+}
+
+type Media struct {
+	Title  string
+	Artist string
+	Cover  Picture
+	Album  string
+	Lyric  string
+	Url    string
+	Header map[string]string
+	User   interface{}
+	Meta   interface{}
+}
+
+func (m *Media) ToUser() *User {
+	if u, ok := m.User.(*User); ok {
+		return u
+	}
+	return &User{Name: m.DanmuUser().Username}
+}
+
+func (m *Media) SystemUser() *User {
+	if u, ok := m.User.(*User); ok {
+		return u
+	}
+	return nil
+}
+
+func (m *Media) DanmuUser() *liveclient.DanmuUser {
+	if u, ok := m.User.(*liveclient.DanmuUser); ok {
+		return u
+	}
+	return nil
+}
+
+func (m *Media) Copy() *Media {
+	newMedia := &Media{}
+	copier.Copy(newMedia, m)
+	return newMedia
+}