package sdwan

import "time"

// SDWANMode represents the traffic distribution strategy.
type SDWANMode string

const (
	ModeWeighted      SDWANMode = "weighted"       // Weighted percentage distribution across healthy links
	ModePCC           SDWANMode = "pcc"            // Per-Connection Classifier (flow hash stickiness)
	ModeLowestLatency SDWANMode = "lowest-latency" // Quality SLA: select link with minimum RTT
	ModeLowestLoss    SDWANMode = "lowest-loss"    // Quality SLA: select link with minimum packet loss
	ModeFailover      SDWANMode = "failover"       // Active-backup priority failover
)

// MemberStatus represents the live health state of an SD-WAN member.
type MemberStatus string

const (
	StatusHealthy  MemberStatus = "HEALTHY"
	StatusDegraded MemberStatus = "DEGRADED"
	StatusDown     MemberStatus = "DOWN"
	StatusDisabled MemberStatus = "DISABLED"
)

// SDWANMember represents a single WAN link participating in an SD-WAN group.
type SDWANMember struct {
	ID          string       `json:"id"`
	Interface   string       `json:"interface"`    // Underlying device name, e.g. "eth0", "eth1", "aerotun0"
	Gateway     string       `json:"gateway"`      // Next-hop IPv4 gateway for this link
	Weight      int          `json:"weight"`       // Relative weight or percentage ratio (default: 50)
	Priority    int          `json:"priority"`     // Priority for failover mode (1 = highest primary)
	TargetProbe string       `json:"target_probe"` // Health check ping target IP (e.g. "1.1.1.1", "8.8.8.8")
	MaxLatency  int          `json:"max_latency"`  // SLA maximum latency threshold in ms (default: 250)
	MaxLoss     int          `json:"max_loss"`     // SLA maximum packet loss threshold in % (default: 20)
	Comment     string       `json:"comment,omitempty"`
	Disabled    bool         `json:"disabled"`

	// Live Telemetry from SLA Prober
	Status           MemberStatus `json:"status"`            // HEALTHY, DEGRADED, DOWN, DISABLED
	LiveLatency      float64      `json:"live_latency"`      // Latency in ms (RTT)
	PacketLoss       float64      `json:"packet_loss"`       // Packet loss percentage (0.0 - 100.0)
	Jitter           float64      `json:"jitter"`            // Latency jitter in ms
	LastChecked      time.Time    `json:"last_checked"`
	ConsecutiveFails     int          `json:"consecutive_fails"`     // Counter for sequential probe failures
	ConsecutiveSuccesses int          `json:"consecutive_successes"` // Counter for sequential probe successes
	TableID              int          `json:"table_id"`              // Kernel routing table ID (e.g. 1101)
	MarkHex          string       `json:"mark_hex"`          // Fwmark hex string (e.g. "0x5d01")
	MarkInt          uint32       `json:"mark_int"`          // Fwmark integer
}

// SDWANGroup represents a unified SD-WAN virtual interface / zone.
type SDWANGroup struct {
	ID            string         `json:"id"`
	Name          string         `json:"name"`           // Group name, e.g. "sdwan0", "sdwan-internet"
	Mode          SDWANMode      `json:"mode"`           // "weighted", "pcc", "lowest-latency", "lowest-loss", "failover"
	HashFields    string         `json:"hash_fields"`    // For PCC: "both-addresses-and-ports", "src-address", "both-addresses"
	AutoNAT       bool           `json:"auto_nat"`       // Automatically masquerade egress traffic from member interfaces
	ProbeInterval int            `json:"probe_interval"` // Health check frequency in seconds (default: 3)
	Comment       string         `json:"comment,omitempty"`
	Disabled      bool           `json:"disabled"`
	Running       bool           `json:"running"`
	Members       []*SDWANMember `json:"members"`
	LastError     string         `json:"last_error,omitempty"`
}

// TelemetrySummary represents summary stats for all SD-WAN groups.
type TelemetrySummary struct {
	TotalGroups    int `json:"total_groups"`
	ActiveGroups   int `json:"active_groups"`
	TotalMembers   int `json:"total_members"`
	HealthyMembers int `json:"healthy_members"`
	DegradedMembers int `json:"degraded_members"`
	DownMembers    int `json:"down_members"`
}