using System;
using UnityEngine;

namespace IdleSpectator;

/// <summary>
/// Presentation-layer character beat: Identity + Beat + Context.
/// Does not mutate InterestCandidate.Label or weaken identity_filter.
/// </summary>
public static class CaptionComposer
{
    public const float ReentrySeconds = 12f;

    private static long _lastCaptionUnitId;
    private static float _lastCaptionAt = -999f;
    private static float _lastCutawayAt = -999f;
    private static long _cutawayFromId;
    private static string _lastFingerprint = "";

    public static string LastIdentityLine { get; private set; } = "";
    public static string LastBeatLine { get; private set; } = "";
    public static string LastContextLine { get; private set; } = "";
    public static long LastReasonRelatedId { get; private set; }
    public static string LastFingerprint => _lastFingerprint;

    public static void Clear()
    {
        _lastCaptionUnitId = 0;
        _lastCaptionAt = -999f;
        _lastCutawayAt = -999f;
        _cutawayFromId = 0;
        _lastFingerprint = "";
        LastIdentityLine = "";
        LastBeatLine = "";
        LastContextLine = "";
        LastReasonRelatedId = 0;
    }

    public static CaptionModel Compose(
        Actor focus,
        InterestCandidate ownedTip,
        string presentableBeat,
        long reasonRelatedId,
        string spineLabel,
        bool statusBannerOwnsBeat)
    {
        var model = new CaptionModel();
        long focusId = EventFeedUtil.SafeId(focus);
        float now = Time.time;

        bool isReentry = false;
        if (focusId != 0 && focusId != _lastCaptionUnitId)
        {
            // Test the returning subject before replacing the cutaway record with
            // the subject we are leaving. Updating first made this comparison
            // impossible: on A -> B -> A, _cutawayFromId was changed to B before
            // A could be recognized as the returning life.
            if (_cutawayFromId == focusId
                && _lastCutawayAt > 0f
                && now - _lastCutawayAt >= ReentrySeconds
                && LifeSagaRoster.IsMc(focusId))
            {
                isReentry = true;
            }

            if (_lastCaptionUnitId != 0)
            {
                _cutawayFromId = _lastCaptionUnitId;
                _lastCutawayAt = now;
            }
        }

        if (focusId != 0)
        {
            _lastCaptionUnitId = focusId;
            _lastCaptionAt = now;
        }

        model.IdentityLine = BuildIdentityLine(focus, focusId);
        model.ReasonRelatedId = reasonRelatedId;

        string beat = presentableBeat ?? "";
        string narrativeContext = "";
        bool structuredNarrativeBeat = false;
        if (!statusBannerOwnsBeat
            && NarrativeProse.TryBuildBeat(
                focus,
                ownedTip,
                out NarrativeBeatModel narrativeModel,
                out string narrativeBeat,
                out narrativeContext))
        {
            beat = narrativeBeat;
            structuredNarrativeBeat = true;
            if (narrativeModel.OtherId != 0)
            {
                model.ReasonRelatedId = narrativeModel.OtherId;
            }
        }

        if (statusBannerOwnsBeat)
        {
            // Banner owns orange row; composer still fills Identity + Context.
            model.BeatLine = "";
        }
        else
        {
            model.BeatLine = structuredNarrativeBeat
                ? beat
                : EnrichBeat(focus, focusId, ownedTip, beat, ref model.ReasonRelatedId, isReentry);
            if (!isReentry)
            {
                model.BeatLine = RemoveIdentitySubjectPrefix(focus, model.BeatLine);
            }
        }

        model.ContextLine = BuildContext(
            focusId,
            ownedTip,
            model.BeatLine,
            model.IdentityLine,
            spineLabel,
            isReentry && !statusBannerOwnsBeat);
        if (!string.IsNullOrEmpty(narrativeContext))
        {
            model.ContextLine = narrativeContext;
        }

        model.Fingerprint =
            focusId + "|" + model.IdentityLine + "|" + model.BeatLine + "|" + model.ContextLine
            + "|" + model.ReasonRelatedId + "|" + SagaProse.MemoryRevision;

        LastIdentityLine = model.IdentityLine;
        LastBeatLine = model.BeatLine;
        LastContextLine = model.ContextLine;
        LastReasonRelatedId = model.ReasonRelatedId;
        _lastFingerprint = model.Fingerprint;
        return model;
    }

    public static string TruncateIdentity(string identity, int maxChars)
    {
        if (string.IsNullOrEmpty(identity) || maxChars <= 0 || identity.Length <= maxChars)
        {
            return identity ?? "";
        }

        // Prefer Name · FirstTitleToken…
        int sep = identity.IndexOf(" · ", StringComparison.Ordinal);
        if (sep > 0)
        {
            string name = identity.Substring(0, sep);
            string rest = identity.Substring(sep + 3).Trim();
            string firstToken = rest;
            int sp = rest.IndexOf(' ');
            if (sp > 0)
            {
                firstToken = rest.Substring(0, sp);
            }

            string compact = name + " · " + firstToken;
            if (compact.Length <= maxChars)
            {
                return compact + "…";
            }

            if (name.Length + 1 < maxChars)
            {
                return name.Substring(0, Math.Min(name.Length, maxChars - 1)) + "…";
            }
        }

        return identity.Substring(0, Math.Max(1, maxChars - 1)) + "…";
    }

    private static string BuildIdentityLine(Actor focus, long focusId)
    {
        if (focus == null || focusId == 0)
        {
            return "";
        }

        string name = EventFeedUtil.SafeName(focus);
        if (string.IsNullOrEmpty(name))
        {
            name = "Someone";
        }

        // Strip Prefer star if presentation added it elsewhere.
        if (name.StartsWith("★ ", StringComparison.Ordinal))
        {
            name = name.Substring(2).Trim();
        }

        string speciesJob = UnitDossier.BuildHeadline(
            name,
            UnitDossier.BuildIdentityTag(
                focus.asset != null ? focus.asset.id : "",
                UnitDossier.ReadLiveJobLabel(focus)));

        if (!LifeSagaRoster.IsMc(focusId))
        {
            return speciesJob;
        }

        LifeSagaSlot slot = LifeSagaRoster.Get(focusId);
        LifeSagaLifeMemory memory = LifeSagaMemory.Get(focusId);
        string title = SagaProse.Title(slot, focus, memory);
        if (string.IsNullOrEmpty(title))
        {
            return speciesJob;
        }

        return name + " · " + title;
    }

    private static string EnrichBeat(
        Actor focus,
        long focusId,
        InterestCandidate tip,
        string beat,
        ref long relatedId,
        bool isReentry)
    {
        if (string.IsNullOrEmpty(beat))
        {
            return "";
        }

        string result = beat;
        long otherId = relatedId;
        if (otherId == 0 && tip != null)
        {
            otherId = tip.RelatedId != 0 ? tip.RelatedId : tip.PairPartnerId;
        }

        if (otherId == 0 && tip != null && tip.PairPartnerId != 0)
        {
            otherId = tip.PairPartnerId;
        }

        if (otherId != 0)
        {
            relatedId = otherId;
        }

        // Ensemble tips: no cast-name injection; rematch clause OK when pair/related already named.
        bool ensemble = SagaProse.IsEnsembleTip(beat);
        Actor other = otherId != 0 ? EventFeedUtil.FindAliveById(otherId) : null;
        if (other == null && otherId != 0)
        {
            other = EventFeedUtil.FindUnitById(otherId);
        }

        if (focusId != 0 && otherId != 0 && other != null)
        {
            RelationEvidence ev = SagaProse.ResolveRelation(focusId, otherId, focus, other);
            string verb = SagaProse.ClassifyTipVerb(beat);
            string clause = SagaProse.BeatClause(focus, other, ev, beat, verb);
            if (!string.IsNullOrEmpty(clause))
            {
                // Skip weak clauses on pure ensemble without the other name in tip.
                if (ensemble)
                {
                    string otherName = EventFeedUtil.SafeName(other);
                    if (!string.IsNullOrEmpty(otherName)
                        && beat.IndexOf(otherName, StringComparison.OrdinalIgnoreCase) < 0
                        && tip != null
                        && tip.PairPartnerId == 0
                        && tip.RelatedId == 0)
                    {
                        clause = "";
                    }
                }

                if (!string.IsNullOrEmpty(clause)
                    && result.IndexOf(clause, StringComparison.OrdinalIgnoreCase) < 0)
                {
                    result = result.TrimEnd() + " · " + clause;
                }
            }
        }

        if (isReentry && LifeSagaRoster.IsMc(focusId))
        {
            string n = EventFeedUtil.SafeName(focus);
            if (!string.IsNullOrEmpty(n)
                && result.StartsWith(n, StringComparison.Ordinal)
                && result.IndexOf(" again", StringComparison.OrdinalIgnoreCase) < 0)
            {
                // "Name again · rest" or "Name is …" → "Name again is …" is awkward.
                // Prefer "Name again · " only when tip doesn't already start with Name + again.
                if (result.StartsWith(n + " ", StringComparison.Ordinal))
                {
                    result = n + " again · " + result.Substring(n.Length).TrimStart();
                }
            }
        }

        return result;
    }

    /// <summary>
    /// Identity already names the focused life directly above the Beat. Remove only that
    /// leading subject (plain or our exact rich-name wrapper), leaving other names intact.
    /// </summary>
    private static string RemoveIdentitySubjectPrefix(Actor focus, string beat)
    {
        if (focus == null || string.IsNullOrEmpty(beat))
        {
            return beat ?? "";
        }

        string name = EventFeedUtil.SafeName(focus);
        if (string.IsNullOrEmpty(name))
        {
            return beat;
        }

        string rest = "";
        string richName = ActivityProse.ColorName(name);
        if (beat.StartsWith(richName + " ", StringComparison.Ordinal))
        {
            rest = beat.Substring(richName.Length).TrimStart();
        }
        else if (beat.StartsWith(name + " ", StringComparison.Ordinal))
        {
            rest = beat.Substring(name.Length).TrimStart();
        }

        return string.IsNullOrEmpty(rest) ? beat : SagaProse.Sentence(rest);
    }

    private static string BuildContext(
        long focusId,
        InterestCandidate tip,
        string beatLine,
        string identityLine,
        string spineLabel,
        bool isReentry)
    {
        string spine = spineLabel ?? "";
        if (!string.IsNullOrEmpty(spine))
        {
            return spine;
        }

        if (!LifeSagaRoster.IsMc(focusId))
        {
            return "";
        }

        string tipMood = TipMood(beatLine, tip);
        // Walk strongest → weaker so a soft tip can skip a kill/role hitch and still
        // show an ongoing war/plot/rival stake when one exists.
        LifeSagaFact stake = PickHitchStake(focusId, beatLine, tipMood, identityLine ?? "");
        if (stake == null)
        {
            return "";
        }

        return SagaProse.StakeLine(stake) ?? "";
    }

    private static LifeSagaFact PickHitchStake(
        long focusId,
        string beatLine,
        string tipMood,
        string identityLine)
    {
        LifeSagaFact best = LifeSagaMemory.StrongestUnresolved(focusId);
        if (best != null
            && !BeatCoversStake(beatLine, best)
            && !ShouldOmitStakeHitch(best, tipMood, identityLine))
        {
            return best;
        }

        var facts = LifeSagaMemory.FactsFor(focusId);
        LifeSagaFact next = null;
        for (int i = 0; i < facts.Count; i++)
        {
            LifeSagaFact f = facts[i];
            if (f == null || f.Resolved || ReferenceEquals(f, best))
            {
                continue;
            }

            if (BeatCoversStake(beatLine, f) || ShouldOmitStakeHitch(f, tipMood, identityLine))
            {
                continue;
            }

            // Only promote stake-worthy / fallback-worthy unresolved facts.
            if (LifeSagaMemory.IsUnresolvedStakeCandidate(f)
                && (next == null
                    || f.Strength > next.Strength
                    || (Mathf.Approximately(f.Strength, next.Strength) && f.At > next.At)))
            {
                next = f;
            }
        }

        return next;
    }

    /// <summary>
    /// Soft live tips (love/rest/dream) should not hitch closed biography
    /// (kills, crowning, founding). Ongoing pressure (war/plot/rival/grief) still may.
    /// </summary>
    private static bool ShouldOmitStakeHitch(LifeSagaFact stake, string tipMood, string identityLine)
    {
        if (stake == null)
        {
            return true;
        }

        // RoleChange that already sits in Identity ("King of X") is always redundant.
        if (stake.Kind == LifeSagaFactKind.RoleChange
            && RoleChangeEchoesIdentity(stake, identityLine))
        {
            return true;
        }

        // "Founder" in Identity already carries the founding fact; repeating
        // "Founded kingdom" immediately below it adds no new information.
        if (stake.Kind == LifeSagaFactKind.Founding
            && identityLine.IndexOf("founder", StringComparison.OrdinalIgnoreCase) >= 0)
        {
            return true;
        }

        bool soft = tipMood == "love" || tipMood == "rest";
        if (!soft)
        {
            return false;
        }

        switch (stake.Kind)
        {
            case LifeSagaFactKind.Kill:
            case LifeSagaFactKind.CombatEncounter:
            case LifeSagaFactKind.HardArcCombat:
            case LifeSagaFactKind.RoleChange:
            case LifeSagaFactKind.Founding:
            case LifeSagaFactKind.HomeGained:
            case LifeSagaFactKind.HomeLost:
                return true;
            default:
                return false;
        }
    }

    private static bool RoleChangeEchoesIdentity(LifeSagaFact stake, string identityLine)
    {
        if (string.IsNullOrEmpty(identityLine))
        {
            return false;
        }

        string body = SagaProse.StakeLine(stake) ?? "";
        if (string.IsNullOrEmpty(body))
        {
            return false;
        }

        // "Became Pack Alpha" under Identity "Name · Pack Alpha".
        string lowerId = identityLine.ToLowerInvariant();
        string lowerBody = body.ToLowerInvariant();
        if (lowerBody.StartsWith("became ", StringComparison.Ordinal))
        {
            string role = lowerBody.Substring("became ".Length).Trim();
            if (role.Length >= 4 && lowerId.IndexOf(role, StringComparison.Ordinal) >= 0)
            {
                return true;
            }
        }

        string[] roleTokens =
        {
            "king", "queen", "leader", "alpha", "chief", "captain", "founder"
        };
        for (int i = 0; i < roleTokens.Length; i++)
        {
            string t = roleTokens[i];
            if (lowerBody.IndexOf(t, StringComparison.Ordinal) >= 0
                && lowerId.IndexOf(t, StringComparison.Ordinal) >= 0)
            {
                return true;
            }
        }

        return false;
    }

    private static string TipMood(string beatLine, InterestCandidate tip)
    {
        string verb = SagaProse.ClassifyTipVerb(beatLine);
        if (verb == "love" || verb == "rest" || verb == "grief" || verb == "combat" || verb == "plot")
        {
            return verb;
        }

        if (tip != null && !string.IsNullOrEmpty(tip.StatusId))
        {
            string sid = tip.StatusId.ToLowerInvariant();
            if (sid.IndexOf("pregnant", StringComparison.Ordinal) >= 0
                || sid.IndexOf("love", StringComparison.Ordinal) >= 0
                || sid.IndexOf("fell_in_love", StringComparison.Ordinal) >= 0)
            {
                return "love";
            }

            if (sid.IndexOf("sleep", StringComparison.Ordinal) >= 0
                || sid.IndexOf("dream", StringComparison.Ordinal) >= 0
                || sid.IndexOf("afterglow", StringComparison.Ordinal) >= 0)
            {
                return "rest";
            }
        }

        return verb;
    }

    private static bool BeatCoversStake(string beat, LifeSagaFact stake)
    {
        if (string.IsNullOrEmpty(beat) || stake == null)
        {
            return false;
        }

        if (stake.OtherId != 0 && !string.IsNullOrEmpty(stake.Other.Name)
            && beat.IndexOf(stake.Other.Name, StringComparison.OrdinalIgnoreCase) >= 0)
        {
            return true;
        }

        string stakeText = SagaProse.StakeLine(stake);
        if (!string.IsNullOrEmpty(stakeText)
            && beat.IndexOf(stakeText, StringComparison.OrdinalIgnoreCase) >= 0)
        {
            return true;
        }

        // Rematch clash clause already teaches the feud.
        if (beat.IndexOf("clash", StringComparison.OrdinalIgnoreCase) >= 0
            && stake.Kind == LifeSagaFactKind.RivalEarned)
        {
            return true;
        }

        return false;
    }
}

public sealed class CaptionModel
{
    public string IdentityLine = "";
    public string BeatLine = "";
    public string ContextLine = "";
    public long ReasonRelatedId;
    public string Fingerprint = "";
}