package tgsig

import (
	"sync"

	"dev.narayana.im/narayana/telegabber/calls/audio"
	"dev.narayana.im/narayana/telegabber/calls/signaling"

	log "github.com/sirupsen/logrus"
	"github.com/zelenin/go-tdlib/client"
)

// per-call tg-side state shared by Caller and Callee
type callBase struct {
	adapter *Adapter
	userID  int64
	isVideo bool
	// CallerSide / CalleeSide - lets ntg callbacks fire MediaConnected per-side
	side signaling.Side

	mu     sync.Mutex
	bridge *signaling.Bridge
	callID int32
}

// must run before any callback that re-enters the bridge
func (b *callBase) Bind(br *signaling.Bridge) {
	b.mu.Lock()
	b.bridge = br
	b.mu.Unlock()
}

func (b *callBase) getBridge() *signaling.Bridge {
	b.mu.Lock()
	defer b.mu.Unlock()
	return b.bridge
}

func (b *callBase) getCallID() int32 {
	b.mu.Lock()
	defer b.mu.Unlock()
	return b.callID
}

func (b *callBase) setCallID(id int32) {
	b.mu.Lock()
	b.callID = id
	b.mu.Unlock()
}

// audio-layer view of the ntgcalls client; nil for signaling-only tests
func (b *callBase) NtgClient() audio.NtgClient { return b.adapter.audioNtg }

// for P2P calls this is ntgcalls' "chatId" - the remote user_id
func (b *callBase) ChatID() int64 { return b.userID }

// ask tdlib to discard; map removal happens in cleanup from
// Manager.endCall once tdlib echoes Discarded.
//
// Duration matters: with 0 the call shows up as missed on other tdlib
// clients of the same account.
func (b *callBase) Terminate(reason signaling.TerminationReason) {
	callID := b.getCallID()
	if callID == 0 {
		// CreateCall never succeeded
		return
	}
	var duration int32
	if br := b.getBridge(); br != nil {
		duration = int32(br.Duration().Seconds())
	}
	b.adapter.withCallContext(func() {
		if _, err := b.adapter.tdlib.DiscardCall(&client.DiscardCallRequest{
			CallId:         callID,
			IsDisconnected: reason == signaling.ReasonMediaFailed,
			Duration:       duration,
			IsVideo:        b.isVideo,
			ConnectionId:   0,
		}); err != nil {
			log.WithFields(log.Fields{
				"call_id":  callID,
				"user_id":  b.userID,
				"reason":   reason,
				"duration": duration,
			}).WithError(err).Error("DiscardCall failed")
		}
	})
}

// drives the ntgcalls P2P setup on tdlib's CallStateReady
func (b *callBase) onReady(state *client.CallStateReady, isOutgoing bool, entry *log.Entry) {
	b.adapter.withCallContext(func() {
		a := b.adapter
		if err := a.ntg.CreateP2PCall(b.userID); err != nil {
			entry.WithError(err).Error("Failed to create P2P call")
			return
		}
		if err := a.ntg.SkipExchange(b.userID, state.EncryptionKey, isOutgoing); err != nil {
			entry.WithError(err).Error("Failed to skip exchange")
			_ = a.ntg.Stop(b.userID)
			return
		}
		rtcServers := convertCallServers(state.Servers)
		versions := state.Protocol.LibraryVersions
		if err := a.ntg.ConnectP2P(b.userID, rtcServers, versions, state.AllowP2p); err != nil {
			entry.WithError(err).Error("Failed to connect P2P")
			_ = a.ntg.Stop(b.userID)
			return
		}
		entry.Info("P2P connection established")
	})
}

// drops the side from both maps and stops ntgcalls
func (b *callBase) cleanup() {
	b.adapter.withCallContext(func() {
		a := b.adapter
		callID := b.getCallID()
		if callID != 0 {
			a.mgr.Drop(a.jid, callID)
		}
		a.dropSide(b.userID)
		if err := a.ntg.Stop(b.userID); err != nil {
			log.WithFields(log.Fields{
				"call_id": callID,
				"user_id": b.userID,
			}).WithError(err).Debug("ntgcalls Stop returned error (call may not have started)")
		}
	})
}