package game

import (
	"fmt"
	"strings"

	"thehouseoficarus/internal/net"
	"thehouseoficarus/internal/player"
	"thehouseoficarus/internal/world"
)

// enterSeq is an in-flight on_enter cutscene for a single player. It is driven
// one step at a time by EnterSeqTick.
type enterSeq struct {
	sess       *net.Session
	playerName string
	roomID     int
	steps      []world.EnterStep
	wait       int
	started    bool
}

// runEnterSteps evaluates a room's on_enter script for the player. Steps whose
// condition fails are dropped. If none of the surviving steps are "timed"
// (no delay, no flag mutation) the messages are printed synchronously, exactly
// as before. Otherwise the surviving steps become a scheduled cutscene driven
// by EnterSeqTick.
func (g *Game) runEnterSteps(sess *net.Session, roomID int) {
	room, err := g.World.LoadRoom(roomID)
	if err != nil || len(room.OnEnter) == 0 {
		return
	}
	p := sess.Player
	if p == nil {
		return
	}

	var steps []world.EnterStep
	cutscene := false
	for _, step := range room.OnEnter {
		if step.Condition != nil && !g.checkCondition(sess, step.Condition) {
			continue
		}
		steps = append(steps, step)
		if step.IsTimed() {
			cutscene = true
		}
	}
	if len(steps) == 0 {
		return
	}

	if !cutscene {
		for _, step := range steps {
			if step.Message != "" {
				sess.WriteLine(step.Message)
			}
		}
		return
	}

	g.startEnterCutscene(sess, p, roomID, steps)
}

// startEnterCutscene registers a scheduled on_enter sequence and persists a
// marker on the player so the cutscene can be resumed on reconnect if it is
// interrupted (disconnect, server restart).
func (g *Game) startEnterCutscene(sess *net.Session, p *player.Player, roomID int, steps []world.EnterStep) {
	g.cancelEnterSeq(p.Name)
	if p.CutsceneRoom != roomID {
		p.CutsceneRoom = roomID
		g.AccountStore.SaveCharacter(p)
	}
	g.enterMu.Lock()
	g.enterSeqs[p.Name] = &enterSeq{
		sess:       sess,
		playerName: p.Name,
		roomID:     roomID,
		steps:      steps,
		wait:       steps[0].Delay,
	}
	g.enterMu.Unlock()
}

// EnterSeqTick advances every in-flight cutscene by one tick. Sequences for a
// player who is no longer connected are paused (left for resume); sequences are
// removed from the map on completion or cancellation.
func (g *Game) EnterSeqTick() {
	g.enterMu.Lock()
	seqs := make([]*enterSeq, 0, len(g.enterSeqs))
	for _, s := range g.enterSeqs {
		seqs = append(seqs, s)
	}
	g.enterMu.Unlock()

	for _, seq := range seqs {
		if !g.isCharLive(seq.playerName, seq.sess) {
			continue
		}

		var jobs []world.EnterStep
		done := false

		g.enterMu.Lock()
		if g.enterSeqs[seq.playerName] != seq {
			g.enterMu.Unlock()
			continue
		}
		seq.wait--
		for seq.wait <= 0 && len(seq.steps) > 0 {
			step := seq.steps[0]
			seq.steps = seq.steps[1:]
			jobs = append(jobs, step)
			if len(seq.steps) > 0 {
				seq.wait = seq.steps[0].Delay
			} else {
				seq.wait = 0
			}
		}
		if len(seq.steps) == 0 {
			done = true
			delete(g.enterSeqs, seq.playerName)
		}
		g.enterMu.Unlock()

		for _, step := range jobs {
			g.fireEnterStep(seq, step)
		}
		if done {
			g.completeEnterSeq(seq)
		}
	}
}

func (g *Game) fireEnterStep(seq *enterSeq, step world.EnterStep) {
	p := seq.sess.Player
	if p == nil || p.RoomID != seq.roomID {
		return
	}
	if step.Message != "" {
		// Break from the prompt on the first line only, so a multi-line
		// cutscene reads as tight consecutive lines.
		if !seq.started {
			seq.sess.WriteLine("\n" + step.Message)
			seq.started = true
		} else {
			seq.sess.WriteLine(step.Message)
		}
	}
	if len(step.SetFlags) > 0 || len(step.SetPlayerFlags) > 0 {
		g.applyFlagMutations(p, step.SetFlags, step.SetPlayerFlags)
		g.AccountStore.SaveCharacter(p)
	}
}

func (g *Game) completeEnterSeq(seq *enterSeq) {
	if !g.isCharLive(seq.playerName, seq.sess) {
		return
	}
	p := seq.sess.Player
	if p == nil {
		return
	}
	if p.CutsceneRoom == seq.roomID {
		p.CutsceneRoom = 0
		g.AccountStore.SaveCharacter(p)
	}
	g.writePrompt(seq.sess)
}

// cancelEnterSeq drops any in-flight cutscene for the player. It does not touch
// the persisted CutsceneRoom marker, so a cutscene cancelled by disconnect can
// still be resumed on reconnect.
func (g *Game) cancelEnterSeq(name string) {
	g.enterMu.Lock()
	delete(g.enterSeqs, name)
	g.enterMu.Unlock()
}

func (g *Game) isCharLive(name string, sess *net.Session) bool {
	g.charsMu.Lock()
	defer g.charsMu.Unlock()
	return g.loggedInChars[name] == sess
}

// applyFlagMutations sets world and player flags, shared by on_enter steps and
// exit traversal.
func (g *Game) applyFlagMutations(p *player.Player, setFlags, setPlayerFlags map[string]any) {
	g.Flags.SetAll(setFlags)
	if len(setPlayerFlags) > 0 {
		p.EnsureFlags()
		for k, v := range setPlayerFlags {
			p.Flags[k] = v
		}
	}
}

func (g *Game) BroadcastRespawns() {
	respawns := g.World.FlushObjRespawns()
	for _, st := range respawns {
		def, err := g.ObjectStore.Load(st.DefID)
		if err != nil || !def.IsGatherable() {
			continue
		}
		cfg := def.Gather
		if cfg.RespawnBroadcast == "" {
			continue
		}
		name := def.Name
		if idx := st.Index + 1; len(g.World.FindObjInstances(st.RoomID, st.DefID)) > 1 {
			name += fmt.Sprintf(" [%d]", idx)
		}
		msg := strings.ReplaceAll(cfg.RespawnBroadcast, "{name}", name)
		if g.Hub != nil {
			for _, sess := range g.Hub.PlayersInRoom(st.RoomID) {
				sess.WriteLine(g.colorize(sess, "broadcast", fmt.Sprintf("\n%s", msg)))
			}
		}
	}
}