package graph

import (
	"fmt"

	confpb "code.hackerspace.pl/q3k/topo/proto/config"
	"github.com/golang/glog"
)

type MachinePort struct {
	OtherEnd *SwitchPort
	Name     string
}

type SwitchPort struct {
	OtherEnd *MachinePort
	Name     string
}

type Machine struct {
	Name     string
	Complete bool

	Ports map[string]*MachinePort
}

type Switch struct {
	Name     string
	Complete bool

	Ports map[string]*SwitchPort
}

type Graph struct {
	Switches map[string]*Switch
	Machines map[string]*Machine
}

func New() *Graph {
	return &Graph{
		Switches: make(map[string]*Switch),
		Machines: make(map[string]*Machine),
	}
}

func (g *Graph) RemoveMachine(name string) {
	glog.Infof("Removed machine %q", name)
}

func (g *Graph) RemoveSwitch(name string) {
	glog.Infof("Removed switch %q", name)
}

func (g *Graph) LoadConfig(conf *confpb.Config) error {
	loadedMachines := make(map[string]bool)
	loadedSwitches := make(map[string]bool)

	// Add new machines and switches.
	for _, machinepb := range conf.Machine {
		if machinepb.Name == "" {
			return fmt.Errorf("empty machine name")
		}
		machine, ok := g.Machines[machinepb.Name]
		if !ok {
			machine = &Machine{
				Name:  machinepb.Name,
				Ports: make(map[string]*MachinePort),
			}
			for _, portpb := range machinepb.ManagedPort {
				machine.Ports[portpb.Name] = &MachinePort{
					Name: portpb.Name,
				}
			}
			g.Machines[machinepb.Name] = machine
			glog.Infof("Added machine %q with %d managed ports", machine.Name, len(machine.Ports))
		}
		machine.Complete = false
		loadedMachines[machinepb.Name] = true
	}
	for _, switchpb := range conf.Switch {
		if switchpb.Name == "" {
			return fmt.Errorf("empty switch name")
		}
		sw, ok := g.Switches[switchpb.Name]
		if !ok {
			sw = &Switch{
				Name:  switchpb.Name,
				Ports: make(map[string]*SwitchPort),
			}
			for _, portpb := range switchpb.ManagedPort {
				sw.Ports[portpb.Name] = &SwitchPort{
					Name: portpb.Name,
				}
			}
			g.Switches[switchpb.Name] = sw
			glog.Infof("Added switch %q with %d managed ports", sw.Name, len(sw.Ports))
		}
		sw.Complete = false
		loadedSwitches[switchpb.Name] = true
	}

	// Remove old machines and switches.
	removeMachines := make(map[string]bool)
	removeSwitches := make(map[string]bool)
	for name, _ := range g.Switches {
		if !loadedSwitches[name] {
			removeSwitches[name] = true
		}
	}
	for name, _ := range g.Machines {
		if !loadedMachines[name] {
			removeMachines[name] = true
		}
	}
	for name, _ := range removeMachines {
		g.RemoveMachine(name)
	}
	for name, _ := range removeSwitches {
		g.RemoveSwitch(name)
	}
	return nil

}