package hosted

// Hosted rooms phase 2 (t5de-hub's docs/hosted-rooms.md, "Phase 2"): the client's own room actions, for hosted
// rooms. Boots are the room's "*boot <booter> <booted>" chat line (every client acts on it) and a room.boot to the
// hub; invitations go through the hub (the inviter's client polls chat.attemptInvite; the invitee's gets a
// "chatInvite" on its user queue); favorites, ratings and the room list's occupancy come from the hub.

import (
	"context"
	"encoding/json"
	"fmt"
	"net/http"
	"net/url"
	"strconv"
	"strings"
	"time"

	"git.t5de.dev/t5de/t5de-proxy/internal/imq"
	"git.t5de.dev/t5de/t5de-proxy/internal/proxy"
	"git.t5de.dev/t5de/t5de-proxy/internal/xmlrpc"
)

// The client's reason codes for refused joins: booted (it shows "booted"), and full (IMVU's own wording).
const (
	errorPublicRoomFull   = 5
	errorPublicRoomBooted = 4
)

// invite is an invitation the client sent (outgoing, by the local ID the client knows) or got (incoming).
type invite struct {
	room  int64
	hub   string // the hub's invite ID ("" until the hub answers)
	to    int64  // outgoing: who
	from  int64  // incoming: who
	state string // outgoing: "waiting", "accepted", "declined"
	note  string // why it was declined
}

func (r *Rooms) newInviteLocked(in *invite) int64 {
	if r.invites == nil {
		r.invites = map[int64]*invite{}
	}
	r.nextInvite++
	r.invites[r.nextInvite] = in
	return r.nextInvite
}

// --- from the hub ---

func (r *Rooms) phase2FromHub(kind string, data []byte) {
	var m struct {
		Room         int64         `json:"room"`
		ImvuID       int64         `json:"imvu_id"`
		OK           bool          `json:"ok"`
		Invite       string        `json:"invite"`
		To           int64         `json:"to"`
		From         int64         `json:"from"`
		Accept       bool          `json:"accept"`
		Offline      bool          `json:"offline"`
		Note         string        `json:"note"`
		Reason       string        `json:"reason"`
		Message      string        `json:"message"`
		RoomName     string        `json:"room_name"`
		Participants []Participant `json:"participants"`
	}
	if json.Unmarshal(data, &m) != nil {
		return
	}
	switch kind {
	case "room.invite_result":
		r.mu.Lock()
		for _, in := range r.invites {
			if in.room == m.Room && in.to == m.ImvuID && in.hub == "" && in.state == "waiting" {
				if m.OK {
					in.hub = m.Invite
				} else {
					in.state, in.note = "declined", m.Message
				}
				break
			}
		}
		r.mu.Unlock()
	case "room.invite_answer":
		r.mu.Lock()
		for _, in := range r.invites {
			if in.hub == m.Invite && in.state == "waiting" {
				switch {
				case m.Offline:
					in.state, in.note = "declined", "isn't online"
				case m.Accept:
					in.state = "accepted"
				default:
					in.state, in.note = "declined", m.Note
				}
			}
		}
		r.mu.Unlock()
	case "room.invited":
		go r.deliverInvite(m.Room, m.Invite, m.From)
	case "room.occupancy":
		r.occupancy(m.Room, m.Participants)
	case "room.boot_result":
		if !m.OK {
			r.logf("hosted: booting %d from room %d: %s", m.ImvuID, m.Room, m.Message)
		}
	}
}

// deliverInvite gives the client an invitation into a hosted room, as IMVU's server does ("chatInvite <json>" on its
// user queue, mount web_msg).
func (r *Rooms) deliverInvite(n int64, hubID string, from int64) {
	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
	defer cancel()
	rm, _, _, err := r.getRoom(ctx, n)
	if err != nil || r.UserDeliver == nil {
		return
	}
	inviter := r.profile(ctx, from)
	for _, p := range r.people(ctx, n) {
		if p.ImvuID == from && p.Name != "" {
			inviter["name"] = plain(p.Name)
		}
	}
	r.mu.Lock()
	local := r.newInviteLocked(&invite{room: n, hub: hubID, from: from})
	r.mu.Unlock()
	rating := 0
	if rm.Rating == "adult" {
		rating = 1
	}
	instance := instanceID(rm.OwnerImvuID, n)
	// location is what the invitation dialog shows of the room.
	location := map[string]any{"name": plain(rm.Name), "private": rm.Privacy == "private", "imageUrl": rm.Image,
		"ownerName": plain(rm.OwnerName), "language": "", "currentOccupancy": rm.Occupancy, "maxOccupancy": rm.MaxUsers,
		"description": plain(rm.Description), "rating": rating, "room_instance_id": instance}
	b, _ := json.Marshal(map[string]any{"chatId": Base + n, "inviteId": local, "partnerId": from,
		"location": location, "inviter": inviter})
	if err := r.UserDeliver("web_msg", append([]byte("chatInvite "), b...)); err != nil {
		r.logf("hosted: giving the client an invitation: %v", err)
	}
}

// profile is what the invitation dialog shows of the inviter, from IMVU's public profile.
func (r *Rooms) profile(ctx context.Context, id int64) map[string]any {
	out := map[string]any{"name": "", "age": "", "gender": "", "imageUrl": "", "relationship": ""}
	u := fmt.Sprintf("https://api.imvu.com/user/user-%d", id)
	req, err := http.NewRequestWithContext(ctx, "GET", u, nil)
	if err != nil {
		return out
	}
	resp, err := r.client().Do(req)
	if err != nil {
		return out
	}
	defer resp.Body.Close()
	var body struct {
		Denormalized map[string]struct {
			Data struct {
				Username     string `json:"username"`
				Age          any    `json:"age"`
				Gender       string `json:"gender"`
				ThumbnailURL string `json:"thumbnail_url"`
			} `json:"data"`
		} `json:"denormalized"`
	}
	if resp.StatusCode != http.StatusOK || json.NewDecoder(resp.Body).Decode(&body) != nil {
		return out
	}
	d := body.Denormalized[u].Data
	out["name"], out["gender"], out["imageUrl"] = plain(d.Username), d.Gender, d.ThumbnailURL
	if d.Age != nil {
		out["age"] = fmt.Sprint(d.Age)
	}
	return out
}

func (r *Rooms) client() *http.Client {
	if r.HTTPClient != nil {
		return r.HTTPClient
	}
	return http.DefaultClient
}

type person struct {
	ImvuID int64  `json:"imvu_id"`
	Seat   int    `json:"seat"`
	Name   string `json:"name"`
}

// people is who's in a room, with names.
func (r *Rooms) people(ctx context.Context, n int64) []person {
	var out struct {
		Participants []person `json:"participants"`
	}
	r.Hub.Call(ctx, "GET", fmt.Sprintf("/api/v1/hosted-rooms/%d/participants", n), nil, &out)
	return out.Participants
}

// --- the client's calls ---

// interceptPhase2 answers the client's room actions for hosted rooms; false if the call isn't one.
func (r *Rooms) interceptPhase2(ctx context.Context, x *proxy.Exchange, method string, args xmlrpc.Struct) bool {
	switch method {
	case "chat.attemptInvite":
		n, ok := RoomNumber(member(args, "location"))
		if !ok {
			if chat, err := strconv.ParseInt(member(args, "chatId"), 10, 64); err == nil {
				n, ok = ChatRoom(chat)
			}
		}
		if !ok {
			return false
		}
		x.Response = r.attemptInvite(n, args)
		return true
	case "chat.leaveInviteAwayNote":
		if r.knownInvite(member(args, "inviteId")) {
			x.Response = xmlrpcAnswer(true)
			return true
		}
	case "chat.acceptInvite", "chat.declineInvite":
		local, _ := strconv.ParseInt(member(args, "inviteId"), 10, 64)
		r.mu.Lock()
		in, ok := r.invites[local]
		r.mu.Unlock()
		if !ok || in.from == 0 {
			return false
		}
		accept := method == "chat.acceptInvite"
		reply := map[string]any{"type": "room.invite_reply", "invite": in.hub, "accept": accept}
		if note := member(args, "reason"); !accept && note != "" {
			reply["note"] = note
		}
		r.Hub.Send(reply)
		if !accept {
			x.Response = xmlrpcAnswer(true)
			return true
		}
		// The client joins the room itself when the answer names it (as a public room, not a private chat); that
		// join carries the invite.
		r.mu.Lock()
		if r.accepted == nil {
			r.accepted = map[int64]string{}
		}
		r.accepted[in.room] = in.hub
		instance := r.instanceOfLocked(in.room) // known: the room was looked up for the invitation
		r.mu.Unlock()
		x.Response = xmlrpcAnswer(xmlrpc.Struct{{Name: "chatId", Value: Base + in.room}, {Name: "partnerId", Value: in.from},
			{Name: "room_instance_id", Value: instance}})
		return true
	case "chat.bootOutOfChat":
		// The "*boot" chat line already told the hub (Send); the client only wants an answer.
		if _, ok := RoomNumber(member(args, "roomInstanceId")); ok {
			x.Response = xmlrpcAnswer(true)
			return true
		}
	case "test.addFavoriteRoom", "test.removeFavoriteRoom":
		n, ok := RoomNumber(member(args, "room_instance_id"))
		if !ok {
			return false
		}
		verb := "PUT"
		if method == "test.removeFavoriteRoom" {
			verb = "DELETE"
		}
		if err := r.Hub.Call(ctx, verb, fmt.Sprintf("/api/v1/hosted-rooms/%d/favorite", n), map[string]any{}, nil); err != nil {
			x.Response = xmlrpcAnswer(xmlrpc.Struct{{Name: "error", Value: "T5DE's hub didn't take it: " + err.Error()}})
			return true
		}
		x.Response = xmlrpcAnswer(xmlrpc.Struct{})
		return true
	}
	return false
}

func (r *Rooms) knownInvite(id string) bool {
	local, err := strconv.ParseInt(id, 10, 64)
	if err != nil {
		return false
	}
	r.mu.Lock()
	defer r.mu.Unlock()
	_, ok := r.invites[local]
	return ok
}

// attemptInvite is the inviter's poll: the first call sends the invitation; later ones (with its inviteId) say
// whether it's been answered.
func (r *Rooms) attemptInvite(n int64, args xmlrpc.Struct) *http.Response {
	local, _ := strconv.ParseInt(member(args, "inviteId"), 10, 64)
	r.mu.Lock()
	in, ok := r.invites[local]
	if !ok {
		to, _ := strconv.ParseInt(member(args, "partnerId"), 10, 64)
		in = &invite{room: n, to: to, state: "waiting"}
		local = r.newInviteLocked(in)
	}
	state, note := in.state, in.note
	r.mu.Unlock()
	if !ok {
		r.Hub.Send(map[string]any{"type": "room.invite", "room": n, "imvu_id": in.to})
	}
	switch state {
	case "accepted":
		return xmlrpcAnswer(xmlrpc.Struct{{Name: "inviteId", Value: local}, {Name: "chatId", Value: Base + n}})
	case "declined":
		if note == "" {
			note = "declined"
		}
		return xmlrpcAnswer(xmlrpc.Struct{{Name: "inviteId", Value: local}, {Name: "response", Value: "decline"}, {Name: "reason", Value: note}})
	}
	return xmlrpcAnswer(xmlrpc.Struct{{Name: "inviteId", Value: local}, {Name: "waiting", Value: int64(1)}})
}

// boot tells the hub about a "*boot <booter> <booted>" line the client sent in a hosted room.
func (r *Rooms) boot(n int64, text string) {
	f := strings.Fields(text)
	if len(f) != 3 || f[0] != "*boot" {
		return
	}
	booted, err := strconv.ParseInt(f[2], 10, 64)
	if err != nil {
		return
	}
	r.Hub.Send(map[string]any{"type": "room.boot", "room": n, "imvu_id": booted})
}

// favoriteForm answers the room list's favorite_rooms.php (action=add|remove, room_instance_id) for hosted rooms.
func (r *Rooms) favoriteForm(ctx context.Context, x *proxy.Exchange) bool {
	form := params(x)
	n, ok := RoomNumber(form.Get("room_instance_id"))
	if !ok {
		return false
	}
	verb := "PUT"
	if form.Get("action") == "remove" {
		verb = "DELETE"
	}
	if err := r.Hub.Call(ctx, verb, fmt.Sprintf("/api/v1/hosted-rooms/%d/favorite", n), map[string]any{}, nil); err != nil {
		b, _ := json.Marshal(map[string]any{"error": "T5DE's hub didn't take it: " + err.Error()})
		x.Response = proxy.LocalResponse(200, "application/json", b)
		return true
	}
	x.Response = proxy.LocalResponse(200, "application/json", []byte(`{"result":"success"}`))
	return true
}

// params is a web API call's parameters: its query, then its body (JSON, as imvu.http.securePost sends, or a form).
func params(x *proxy.Exchange) url.Values {
	out := x.URL.Query()
	var body map[string]any
	if json.Unmarshal(x.Body, &body) == nil {
		for k, v := range body {
			switch v := v.(type) {
			case string:
				out.Set(k, v)
			case float64:
				out.Set(k, strconv.FormatFloat(v, 'f', -1, 64))
			case bool:
				out.Set(k, strconv.FormatBool(v))
			}
		}
		return out
	}
	if form, err := url.ParseQuery(string(x.Body)); err == nil {
		for k, v := range form {
			out[k] = v
		}
	}
	return out
}

// --- ratings (room_rating.php) ---

func (r *Rooms) rating(ctx context.Context, x *proxy.Exchange) bool {
	form := params(x)
	n, ok := RoomNumber(form.Get("room_instance_id"))
	if !ok {
		return false
	}
	if score, err := strconv.Atoi(form.Get("score")); err == nil && x.Request.Method == "POST" {
		if err := r.Hub.Call(ctx, "PUT", fmt.Sprintf("/api/v1/hosted-rooms/%d/rating", n), map[string]any{"score": score}, nil); err != nil {
			x.Response = proxy.LocalResponse(200, "application/json", []byte(`{"result":"failure"}`))
			return true
		}
		x.Response = proxy.LocalResponse(200, "application/json", []byte(`{"result":"success"}`))
		return true
	}
	mine := 0
	if rm, _, _, err := r.getRoom(ctx, n); err == nil {
		mine = rm.MyRating
	}
	b, _ := json.Marshal(map[string]any{"score": mine, "result": "success"})
	x.Response = proxy.LocalResponse(200, "application/json", b)
	return true
}

// --- occupancy (room_occupancy/<instance> queues in the room list) ---

// watch subscribes (or unsubscribes) a connection to a room's occupancy, and tells the hub which rooms to report.
func (r *Rooms) watch(c *proxy.IMQConn, n int64, queue string, on bool) []imq.Property {
	r.mu.Lock()
	if r.watched == nil {
		r.watched = map[int64]map[*proxy.IMQConn]string{}
	}
	if on {
		if r.watched[n] == nil {
			r.watched[n] = map[*proxy.IMQConn]string{}
		}
		r.watched[n][c] = queue
	} else if r.watched[n] != nil {
		delete(r.watched[n], c)
		if len(r.watched[n]) == 0 {
			delete(r.watched, n)
		}
	}
	var props []imq.Property
	for key := range r.occupants[n] {
		props = append(props, imq.Property{Key: key, Value: "1"})
	}
	r.mu.Unlock()
	r.sendWatch()
	return props
}

func (r *Rooms) sendWatch() {
	r.mu.Lock()
	rooms := []int64{}
	for n := range r.watched {
		rooms = append(rooms, n)
	}
	r.mu.Unlock()
	r.Hub.Send(map[string]any{"type": "room.watch", "rooms": rooms})
}

// occupancy gives watchers a room's occupants as state changes: a key per person (the client counts them).
func (r *Rooms) occupancy(n int64, participants []Participant) {
	now := map[string]bool{}
	for _, p := range participants {
		now[strconv.FormatInt(p.ImvuID, 10)] = true
	}
	r.mu.Lock()
	if r.occupants == nil {
		r.occupants = map[int64]map[string]bool{}
	}
	before := r.occupants[n]
	r.occupants[n] = now
	watchers := map[*proxy.IMQConn]string{}
	for c, q := range r.watched[n] {
		watchers[c] = q
	}
	r.mu.Unlock()
	var props []imq.Property
	for key := range now {
		if !before[key] {
			props = append(props, imq.Property{Key: key, Value: "1"})
		}
	}
	for key := range before {
		if !now[key] {
			props = append(props, imq.Property{Key: key}) // empty: gone
		}
	}
	if len(props) == 0 {
		return
	}
	for c, queue := range watchers {
		c.Send(imq.G2cStateChange, imq.StateChange(0, "admin", queue, "occupants", props, 0))
	}
}