package main

import (
	"fmt"
	"log"
	"strings"
)

type RemoteHost struct {
	*Client
	Host        string
	MissedPings int
}

func (h *RemoteHost) IsHealthy() bool {
	return !h.Dead && h.MissedPings < 3
}

func (h *RemoteHost) Initialize(p *SyncedPool) {

	ids, err := h.GetCartMappings()
	if err != nil {
		log.Printf("Error getting remote mappings: %v\n", err)
		return
	}
	log.Printf("Remote %s has %d grains\n", h.Host, len(ids))
	p.mu.Lock()
	local := 0
	remoteNo := 0
	for _, id := range ids {
		go p.SpawnRemoteGrain(id, h.Host)
		remoteNo++
	}
	log.Printf("Removed %d local grains, added %d remote grains\n", local, remoteNo)
	p.mu.Unlock()
	go p.Negotiate()

}

func (h *RemoteHost) Ping() error {
	_, err := h.Call(Ping, Pong, []byte{})

	if err != nil {
		h.MissedPings++
		log.Printf("Error pinging remote %s, missed pings: %d", h.Host, h.MissedPings)

	} else {
		h.MissedPings = 0
	}
	return err
}

func (h *RemoteHost) Negotiate(knownHosts []string) ([]string, error) {
	reply, err := h.Call(RemoteNegotiate, RemoteNegotiateResponse, []byte(strings.Join(knownHosts, ";")))

	if err != nil {
		return nil, err
	}
	if reply.StatusCode != 200 {
		return nil, fmt.Errorf("remote returned error on negotiate: %s", string(reply.Data))
	}

	return strings.Split(string(reply.Data), ";"), nil
}

func (g *RemoteHost) GetCartMappings() ([]CartId, error) {
	reply, err := g.Call(GetCartIds, CartIdsResponse, []byte{})
	if err != nil {
		return nil, err
	}
	if reply.StatusCode != 200 {
		log.Printf("Remote returned error on get cart mappings: %s", string(reply.Data))
		return nil, fmt.Errorf("remote returned error: %s", string(reply.Data))
	}
	parts := strings.Split(string(reply.Data), ";")
	ids := make([]CartId, 0, len(parts))
	for _, p := range parts {
		ids = append(ids, ToCartId(p))
	}
	return ids, nil
}

func (r *RemoteHost) ConfirmChange(id CartId, host string) error {
	reply, err := r.Call(RemoteGrainChanged, AckChange, []byte(fmt.Sprintf("%s;%s", id, host)))

	if err != nil {
		return err
	}
	if string(reply.Data) != "ok" {
		return fmt.Errorf("remote grain change failed %s", string(reply.Data))
	}

	return nil
}