From bd307db0d3741a4d48b791518d82b4df4651175c Mon Sep 17 00:00:00 2001
From: Alejandro Mery <amery@jpi.io>
Date: Thu, 24 Aug 2023 21:48:00 +0000
Subject: [PATCH] WIP

Signed-off-by: Alejandro Mery <amery@jpi.io>
---
 pkg/zones/env.go           | 31 ++++++++++------------
 pkg/zones/machine.go       | 23 ++++++++++++++++
 pkg/zones/machine_rings.go | 54 ++++++++++++++++++++++++++++++++++++++
 pkg/zones/zones.go         | 25 ++++++++++++++++++
 4 files changed, 116 insertions(+), 17 deletions(-)

diff --git a/pkg/zones/env.go b/pkg/zones/env.go
index a28496e..174780e 100644
--- a/pkg/zones/env.go
+++ b/pkg/zones/env.go
@@ -10,18 +10,21 @@ import (
 // WriteEnv generates environment variables for shell scripts
 func (m *Zones) WriteEnv(w io.Writer) error {
 	var buf bytes.Buffer
+	var err error
 
 	m.writeEnvVarFn(&buf, genEnvZones, "ZONES")
 	m.ForEachZone(func(z *Zone) bool {
-		m.writeEnvZone(&buf, z)
-		return false
+		err = m.writeEnvZone(&buf, z)
+		return err != nil
 	})
 
-	_, err := buf.WriteTo(w)
+	if err == nil {
+		_, err = buf.WriteTo(w)
+	}
 	return err
 }
 
-func (m *Zones) writeEnvZone(w io.Writer, z *Zone) {
+func (m *Zones) writeEnvZone(w io.Writer, z *Zone) error {
 	zoneID := z.ID
 
 	// ZONE{zoneID}
@@ -35,8 +38,11 @@ func (m *Zones) writeEnvZone(w io.Writer, z *Zone) {
 	m.writeEnvVar(w, fmt.Sprintf("%v", gatewayID), "ZONE%v_%s", zoneID, "GW")
 
 	// ZONE{zoneID}_IP
-	ip, _ := RingZeroAddress(zoneID, gatewayID)
-	m.writeEnvVar(w, ip.String(), "ZONE%v_%s", zoneID, "IP")
+	if ip, ok := RingZeroAddress(zoneID, gatewayID); ok {
+		m.writeEnvVar(w, ip.String(), "ZONE%v_%s", zoneID, "IP")
+	}
+
+	return nil
 }
 
 func (m *Zones) writeEnvVarFn(w io.Writer, fn func(*Zones) string, name string, args ...any) {
@@ -79,13 +85,9 @@ func genEnvZoneNodes(z *Zone) string {
 }
 
 func getRingZeroGatewayID(z *Zone) int {
-	var firstNodeID, gatewayID int
+	var gatewayID int
 
 	z.ForEachMachine(func(p *Machine) bool {
-		if firstNodeID == 0 {
-			firstNodeID = p.ID
-		}
-
 		if p.IsGateway() {
 			gatewayID = p.ID
 		}
@@ -93,10 +95,5 @@ func getRingZeroGatewayID(z *Zone) int {
 		return gatewayID != 0
 	})
 
-	switch {
-	case gatewayID == 0:
-		return firstNodeID
-	default:
-		return gatewayID
-	}
+	return gatewayID
 }
diff --git a/pkg/zones/machine.go b/pkg/zones/machine.go
index f9ceefe..8074d33 100644
--- a/pkg/zones/machine.go
+++ b/pkg/zones/machine.go
@@ -3,10 +3,12 @@ package zones
 import (
 	"net/netip"
 	"strings"
+	"sync"
 )
 
 // A Machine is a machine on a Zone
 type Machine struct {
+	mu   sync.Mutex
 	zone *Zone
 	ID   int
 	Name string `toml:"name"`
@@ -39,6 +41,27 @@ func (m *Machine) IsGateway() bool {
 	return ok
 }
 
+// SetGateway enables/disables a Machine ring0 integration
+func (m *Machine) SetGateway(enabled bool) error {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+
+	ri, found := m.getRingInfo(0)
+	switch {
+	case !found && !enabled:
+		return nil
+	case !found:
+		var err error
+
+		if ri, err = m.createRingInfo(0, false); err != nil {
+			return err
+		}
+	}
+
+	ri.Enabled = enabled
+	return m.syncRingConfig(0)
+}
+
 func (m *Machine) getPeerByName(name string) (*Machine, bool) {
 	return m.zone.zones.GetMachineByName(name)
 }
diff --git a/pkg/zones/machine_rings.go b/pkg/zones/machine_rings.go
index 1e950e8..75ab2bf 100644
--- a/pkg/zones/machine_rings.go
+++ b/pkg/zones/machine_rings.go
@@ -261,3 +261,57 @@ func (m *Machine) RemoveWireguardConfig(ring int) error {
 
 	return err
 }
+
+func (*Machine) syncRingConfig(_ int) error {
+	// _, err := m.getRingNodes(ring)
+	return nil
+}
+
+func (m *Machine) createRingInfo(ring int, enabled bool) (*RingInfo, error) {
+	keys, err := wireguard.NewKeyPair()
+	if err != nil {
+		return nil, err
+	}
+
+	ri := &RingInfo{
+		Ring:    ring,
+		Enabled: enabled,
+		Keys:    keys,
+	}
+
+	err = m.applyRingInfo(ring, ri)
+	if err != nil {
+		return nil, err
+	}
+
+	return ri, nil
+}
+
+func (m *Machine) writeRingInfo(ri *RingInfo) error {
+	var err error
+
+	if m == nil || ri == nil {
+		return fs.ErrInvalid
+	}
+
+	err = m.WriteWireguardKeys(ri.Ring)
+	if err != nil {
+		return err
+	}
+
+	if !ri.Enabled {
+		return m.RemoveWireguardConfig(ri.Ring)
+	}
+
+	return m.writeRingInfoConf(ri.Ring, ri.Keys.PrivateKey)
+}
+
+func (m *Machine) writeRingInfoConf(ring int, _ wireguard.PrivateKey) error {
+	f, err := m.CreateTruncFile("wg%v.conf", ring)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	return nil
+}
diff --git a/pkg/zones/zones.go b/pkg/zones/zones.go
index 817fd97..f6b0d15 100644
--- a/pkg/zones/zones.go
+++ b/pkg/zones/zones.go
@@ -33,6 +33,31 @@ func (z *Zone) ForEachMachine(fn func(*Machine) bool) {
 	}
 }
 
+// SetGateway configures a machine to be the zone's ring0 gateway
+func (z *Zone) SetGateway(gatewayID int, enabled bool) error {
+	var err error
+	var found bool
+
+	z.ForEachMachine(func(p *Machine) bool {
+		if p.ID == gatewayID {
+			found = true
+			err = p.SetGateway(enabled)
+
+			return true
+		}
+		return false
+	})
+
+	switch {
+	case err != nil:
+		return err
+	case !found:
+		return fs.ErrNotExist
+	default:
+		return nil
+	}
+}
+
 // Zones represents all zones in a cluster
 type Zones struct {
 	dir      fs.FS