Split ICE and DTLS related SDP parsing out

Move this stuff out of SetRemoteDescription so it will be easier to test

Relates to #1023

sdp_test.go

@@ -0,0 +1,88 @@
+// +build !js
+
+package webrtc
+
+import (
+	"testing"
+
+	"github.com/pion/sdp/v2"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestExtractFingerprint(t *testing.T) {
+	t.Run("Good Session Fingerprint", func(t *testing.T) {
+		s := &sdp.SessionDescription{
+			Attributes: []sdp.Attribute{{Key: "fingerprint", Value: "foo bar"}},
+		}
+
+		fingerprint, hash, err := extractFingerprint(s)
+		assert.NoError(t, err)
+		assert.Equal(t, fingerprint, "bar")
+		assert.Equal(t, hash, "foo")
+	})
+
+	t.Run("Good Media Fingerprint", func(t *testing.T) {
+		s := &sdp.SessionDescription{
+			MediaDescriptions: []*sdp.MediaDescription{
+				{Attributes: []sdp.Attribute{{Key: "fingerprint", Value: "foo bar"}}},
+			},
+		}
+
+		fingerprint, hash, err := extractFingerprint(s)
+		assert.NoError(t, err)
+		assert.Equal(t, fingerprint, "bar")
+		assert.Equal(t, hash, "foo")
+	})
+
+	t.Run("No Fingerprint", func(t *testing.T) {
+		s := &sdp.SessionDescription{}
+
+		_, _, err := extractFingerprint(s)
+		assert.Equal(t, ErrSessionDescriptionNoFingerprint, err)
+	})
+
+	t.Run("Invalid Fingerprint", func(t *testing.T) {
+		s := &sdp.SessionDescription{
+			Attributes: []sdp.Attribute{{Key: "fingerprint", Value: "foo"}},
+		}
+
+		_, _, err := extractFingerprint(s)
+		assert.Equal(t, ErrSessionDescriptionInvalidFingerprint, err)
+	})
+
+	t.Run("Conflicting Fingerprint", func(t *testing.T) {
+		s := &sdp.SessionDescription{
+			Attributes: []sdp.Attribute{{Key: "fingerprint", Value: "foo"}},
+			MediaDescriptions: []*sdp.MediaDescription{
+				{Attributes: []sdp.Attribute{{Key: "fingerprint", Value: "foo blah"}}},
+			},
+		}
+
+		_, _, err := extractFingerprint(s)
+		assert.Equal(t, ErrSessionDescriptionConflictingFingerprints, err)
+	})
+}
+
+func TestExtractICEDetails(t *testing.T) {
+	t.Run("Missing ice-pwd", func(t *testing.T) {
+		s := &sdp.SessionDescription{
+			MediaDescriptions: []*sdp.MediaDescription{
+				{Attributes: []sdp.Attribute{{Key: "ice-ufrag", Value: "foobar"}}},
+			},
+		}
+
+		_, _, _, err := extractICEDetails(s)
+		assert.Equal(t, err, ErrSessionDescriptionMissingIcePwd)
+	})
+
+	t.Run("Missing ice-ufrag", func(t *testing.T) {
+		s := &sdp.SessionDescription{
+			MediaDescriptions: []*sdp.MediaDescription{
+				{Attributes: []sdp.Attribute{{Key: "ice-pwd", Value: "foobar"}}},
+			},
+		}
+
+		_, _, _, err := extractICEDetails(s)
+		assert.Equal(t, err, ErrSessionDescriptionMissingIceUfrag)
+	})
+}