using Marathon.Domain.Backtesting;
using Marathon.Domain.Entities;
using Marathon.Domain.Enums;
using Marathon.Domain.ValueObjects;
using Marathon.Infrastructure.Persistence.Entities;

namespace Marathon.Infrastructure.Persistence;

/// <summary>
/// Mapping helpers that translate between domain objects and EF Core persistence entities.
/// Domain invariants are enforced on the domain side; mapping is purely structural.
/// </summary>
/// <remarks>
/// ScheduledAt / CapturedAt / DetectedAt / CompletedAt / PlacedAt are encoded and
/// decoded exclusively through <see cref="SqliteDateText"/> so the write format and
/// the repositories' range-predicate format can never drift apart.
/// </remarks>
internal static class Mapping
{
    // ─── Bet scope discriminator constants ────────────────────────────────────
    private const int ScopeMatch = 0;
    private const int ScopePeriod = 1;
    // ─── Event ───────────────────────────────────────────────────────────────

    public static EventEntity ToEntity(Event domain) =>
        new()
        {
            EventCode = domain.Id.Value,
            SportCode = domain.Sport.Value,
            CountryCode = domain.CountryCode,
            LeagueId = domain.LeagueId,
            Category = domain.Category,
            ScheduledAt = SqliteDateText.Key(domain.ScheduledAt),
            Side1Name = domain.Side1Name,
            Side2Name = domain.Side2Name,
            EventPath = domain.EventPath,
        };

    public static Event ToDomain(EventEntity entity) =>
        new(
            Id: new EventId(entity.EventCode),
            Sport: new SportCode(entity.SportCode),
            CountryCode: entity.CountryCode,
            LeagueId: entity.LeagueId,
            Category: entity.Category,
            ScheduledAt: SqliteDateText.Parse(entity.ScheduledAt),
            Side1Name: entity.Side1Name,
            Side2Name: entity.Side2Name)
        {
            EventPath = entity.EventPath,
        };

    // ─── OddsSnapshot ─────────────────────────────────────────────────────────

    public static SnapshotEntity ToEntity(OddsSnapshot domain) =>
        new()
        {
            EventCode = domain.EventId.Value,
            CapturedAt = SqliteDateText.Key(domain.CapturedAt),
            Source = (int)domain.Source,
            Bets = domain.Bets.Select(ToEntity).ToList(),
        };

    public static OddsSnapshot ToDomain(SnapshotEntity entity) =>
        new(
            eventId: new EventId(entity.EventCode),
            capturedAt: SqliteDateText.Parse(entity.CapturedAt),
            source: (OddsSource)entity.Source,
            bets: entity.Bets.Select(ToDomain).ToList().AsReadOnly());

    // ─── Bet ──────────────────────────────────────────────────────────────────

    public static BetEntity ToEntity(Bet domain) =>
        new()
        {
            Scope = domain.Scope is MatchScope ? ScopeMatch : ScopePeriod,
            PeriodNumber = domain.Scope is PeriodScope ps ? ps.Number : null,
            Type = (int)domain.Type,
            Side = (int)domain.Side,
            Value = domain.Value?.Value,
            Rate = domain.Rate.Value,
        };

    public static Bet ToDomain(BetEntity entity)
    {
        var scope = entity.Scope switch
        {
            ScopeMatch => (BetScope)MatchScope.Instance,
            ScopePeriod => new PeriodScope(entity.PeriodNumber!.Value),
            _ => throw new InvalidOperationException(
                $"Unknown BetScope discriminator: {entity.Scope}"),
        };

        var value = entity.Value.HasValue ? new OddsValue(entity.Value.Value) : null;
        var rate = new OddsRate(entity.Rate);
        var type = (BetType)entity.Type;
        var side = (Side)entity.Side;

        return new Bet(scope, type, side, value, rate);
    }

    // ─── EventResult ──────────────────────────────────────────────────────────

    public static EventResultEntity ToEntity(EventResult domain) =>
        new()
        {
            EventCode = domain.EventId.Value,
            Side1Score = domain.Side1Score,
            Side2Score = domain.Side2Score,
            WinnerSide = (int)domain.WinnerSide,
            CompletedAt = SqliteDateText.Key(domain.CompletedAt),
        };

    public static EventResult ToDomain(EventResultEntity entity) =>
        new(
            EventId: new EventId(entity.EventCode),
            Side1Score: entity.Side1Score,
            Side2Score: entity.Side2Score,
            WinnerSide: (Side)entity.WinnerSide,
            CompletedAt: SqliteDateText.Parse(entity.CompletedAt));

    // ─── Anomaly ──────────────────────────────────────────────────────────────

    public static AnomalyEntity ToEntity(Anomaly domain) =>
        new()
        {
            Id = domain.Id.ToString(),
            EventCode = domain.EventId.Value,
            DetectedAt = SqliteDateText.Key(domain.DetectedAt),
            Kind = (int)domain.Kind,
            Score = domain.Score,
            EvidenceJson = domain.EvidenceJson,
        };

    public static Anomaly ToDomain(AnomalyEntity entity) =>
        new(
            Id: Guid.Parse(entity.Id),
            EventId: new EventId(entity.EventCode),
            DetectedAt: SqliteDateText.Parse(entity.DetectedAt),
            Kind: (AnomalyKind)entity.Kind,
            Score: entity.Score,
            EvidenceJson: entity.EvidenceJson);

    // ─── Sport ────────────────────────────────────────────────────────────────

    public static SportEntity ToEntity(Sport domain) =>
        new()
        {
            Code = domain.Code.Value,
            NameRu = domain.NameRu,
            NameEn = domain.NameEn,
        };

    public static Sport ToDomain(SportEntity entity) =>
        new(
            Code: new SportCode(entity.Code),
            NameRu: entity.NameRu,
            NameEn: entity.NameEn);

    // ─── PlacedBet ────────────────────────────────────────────────────────────

    public static PlacedBetEntity ToEntity(PlacedBet domain) =>
        new()
        {
            Id = domain.Id.ToString(),
            EventCode = domain.EventId.Value,
            Scope = domain.Selection.Scope is MatchScope ? ScopeMatch : ScopePeriod,
            PeriodNumber = domain.Selection.Scope is PeriodScope ps ? ps.Number : null,
            Type = (int)domain.Selection.Type,
            Side = (int)domain.Selection.Side,
            Value = domain.Selection.Value?.Value,
            Rate = domain.Selection.Rate.Value,
            Stake = domain.Stake,
            PlacedAt = SqliteDateText.Key(domain.PlacedAt),
            Outcome = (int)domain.Outcome,
            Notes = domain.Notes,
        };

    public static PlacedBet ToDomain(PlacedBetEntity entity)
    {
        var scope = entity.Scope switch
        {
            ScopeMatch => (BetScope)MatchScope.Instance,
            ScopePeriod => new PeriodScope(entity.PeriodNumber!.Value),
            _ => throw new InvalidOperationException(
                $"Unknown BetScope discriminator: {entity.Scope}"),
        };

        var value = entity.Value.HasValue ? new OddsValue(entity.Value.Value) : null;
        var rate = new OddsRate(entity.Rate);
        var type = (BetType)entity.Type;
        var side = (Side)entity.Side;
        var selection = new Bet(scope, type, side, value, rate);

        return new PlacedBet(
            Id: Guid.Parse(entity.Id),
            EventId: new EventId(entity.EventCode),
            Selection: selection,
            Stake: entity.Stake,
            PlacedAt: SqliteDateText.Parse(entity.PlacedAt),
            Outcome: (BetOutcome)entity.Outcome,
            Notes: entity.Notes);
    }

    // ─── League ───────────────────────────────────────────────────────────────

    public static LeagueEntity ToEntity(League domain) =>
        new()
        {
            Id = domain.Id,
            SportCode = domain.Sport.Value,
            Country = domain.Country,
            NameRu = domain.NameRu,
            NameEn = domain.NameEn,
            Category = domain.Category,
        };

    public static League ToDomain(LeagueEntity entity) =>
        new(
            Id: entity.Id,
            Sport: new SportCode(entity.SportCode),
            Country: entity.Country,
            NameRu: entity.NameRu,
            NameEn: entity.NameEn,
            Category: entity.Category);

    // ─── SavedStrategy ─────────────────────────────────────────────────────────

    public static SavedStrategyEntity ToEntity(SavedStrategy domain) =>
        new()
        {
            Id = domain.Id.ToString(),
            Name = domain.Name,
            StartingBankroll = domain.Strategy.StartingBankroll,
            MinScore = domain.Strategy.MinScore,
            StakeRule = (int)domain.Strategy.StakeRule,
            FlatStake = domain.Strategy.FlatStake,
            PercentOfBankroll = domain.Strategy.PercentOfBankroll,
            KellyFraction = domain.Strategy.KellyFraction,
            CreatedAt = SqliteDateText.Key(domain.CreatedAt),
        };

    public static SavedStrategy ToDomain(SavedStrategyEntity entity) =>
        new(
            Id: Guid.Parse(entity.Id),
            Name: entity.Name,
            Strategy: new BacktestStrategy(
                StartingBankroll: entity.StartingBankroll,
                MinScore: entity.MinScore,
                StakeRule: (StakeRule)entity.StakeRule,
                FlatStake: entity.FlatStake,
                PercentOfBankroll: entity.PercentOfBankroll,
                KellyFraction: entity.KellyFraction),
            CreatedAt: SqliteDateText.Parse(entity.CreatedAt));
}