using System.Text.Json;
using Admin.NET.Plugin.AiDOP.Dto.SmartOps;
using Admin.NET.Plugin.AiDOP.Entity;

namespace Admin.NET.Plugin.AiDOP.SmartOps;

public sealed class KpiTargetService : ITransient
{
    public const int MaxImportRows = 10000;
    public const long MaxImportBytes = 5 * 1024 * 1024;

    private readonly IKpiTargetConfigStore _store;
    private readonly IKpiTargetResolver _resolver;
    private readonly UserManager _userManager;

    public KpiTargetService(IKpiTargetConfigStore store, IKpiTargetResolver resolver, UserManager userManager)
    {
        _store = store;
        _resolver = resolver;
        _userManager = userManager;
    }

    public long TenantId => AidopTenantScope.ResolveOrThrow(_userManager);

    public async Task<List<KpiTargetDto>> ListAsync(string metricCode, long? factoryId, CancellationToken ct = default)
    {
        EnsureMetricCode(metricCode);
        var tenantId = TenantId;
        await EnsureKpiAsync(tenantId, metricCode, ct);
        var list = await _store.ListAsync(tenantId, metricCode.Trim(), factoryId, ct);
        return list.Select(KpiTargetRules.ToDto).ToList();
    }

    public async Task<KpiTargetResolveResult> ResolveCurrentAsync(string metricCode, long factoryId, DateTime? bizDate, CancellationToken ct = default)
    {
        EnsureMetricCode(metricCode);
        if (factoryId < 0)
            throw new KpiTargetValidationException("工厂无效");
        var tenantId = TenantId;
        var kpi = await EnsureKpiAsync(tenantId, metricCode, ct);
        var day = (bizDate ?? DateTime.Today).Date;
        var snap = await _resolver.ResolveAsync(tenantId, factoryId, metricCode.Trim(), kpi.ModuleCode, day, ct);
        return new KpiTargetResolveResult
        {
            MetricCode = metricCode.Trim(),
            FactoryId = factoryId,
            BizDate = day.ToString("yyyy-MM-dd"),
            TargetValue = snap.TargetValue,
            TargetConfigId = snap.TargetConfigId,
            TargetSource = snap.TargetSource == KpiTargetSnapshotSource.Missing
                ? KpiTargetSnapshotSource.Missing
                : snap.TargetSource,
            ConfigSourceType = snap.TargetConfigId == null ? null : await ConfigSourceAsync(tenantId, snap.TargetConfigId.Value, ct),
            EffectiveFrom = snap.EffectiveFrom?.ToString("yyyy-MM-dd"),
            EffectiveTo = snap.EffectiveTo?.ToString("yyyy-MM-dd"),
            ResolvedAt = snap.ResolvedAt
        };
    }

    public Task<KpiTargetDto> CreateAsync(KpiTargetCreateDto dto, string sourceType, string? batchId, CancellationToken ct = default) =>
        CreateCoreAsync(TenantId, dto, sourceType, batchId, _userManager.UserId, ct);

    public async Task<KpiTargetDto> CreateCoreAsync(
        long tenantId,
        KpiTargetCreateDto dto,
        string sourceType,
        string? batchId,
        long? userId,
        CancellationToken ct = default)
    {
        EnsureMetricCode(dto.MetricCode);
        if (dto.FactoryId < 0)
            throw new KpiTargetValidationException("工厂无效");
        KpiTargetRules.EnsureTargetPositive(dto.TargetValue);
        var from = KpiTargetRules.Normalize(dto.EffectiveFrom);
        KpiTargetRules.EnsureRange(from, dto.EffectiveTo);
        await EnsureKpiAsync(tenantId, dto.MetricCode, ct);

        var existing = await _store.ListActiveScopeAsync(tenantId, dto.FactoryId, dto.MetricCode.Trim(), ct);
        if (dto.ClosePrevious)
            await ClosePreviousOpenAsync(existing, from, ct);

        var refreshed = await _store.ListActiveScopeAsync(tenantId, dto.FactoryId, dto.MetricCode.Trim(), ct);
        foreach (var row in refreshed.Where(x => x.Status == 1))
        {
            if (KpiTargetRules.Overlaps(row.EffectiveFrom, row.EffectiveTo, from, dto.EffectiveTo))
                throw new KpiTargetConflictException(
                    $"与已有目标重叠：{row.EffectiveFrom:yyyy-MM-dd}~{row.EffectiveTo?.ToString("yyyy-MM-dd") ?? "开放"}");
        }

        var now = DateTime.Now;
        var created = await _store.InsertAsync(new AdoSmartOpsKpiTargetConfig
        {
            TenantId = tenantId,
            FactoryId = dto.FactoryId,
            MetricCode = dto.MetricCode.Trim(),
            TargetValue = dto.TargetValue,
            EffectiveFrom = from,
            EffectiveTo = dto.EffectiveTo?.Date,
            SourceType = sourceType,
            SourceBatchId = batchId,
            Status = 1,
            Remark = dto.Remark,
            CreatedBy = userId,
            UpdatedBy = userId,
            CreateTime = now,
            UpdateTime = now
        }, ct);
        return KpiTargetRules.ToDto(created);
    }

    public Task<KpiTargetDto> UpdateAsync(long id, KpiTargetUpdateDto dto, CancellationToken ct = default) =>
        UpdateCoreAsync(TenantId, id, dto, ct);

    public async Task<KpiTargetDto> UpdateCoreAsync(long tenantId, long id, KpiTargetUpdateDto dto, CancellationToken ct = default)
    {
        var row = await _store.GetByIdAsync(tenantId, id, ct)
            ?? throw new KpiTargetNotFoundException("目标配置不存在");
        var today = DateTime.Today;
        var alreadyEffective = row.Status == 1 && row.EffectiveFrom.Date <= today;

        if (dto.TargetValue.HasValue)
        {
            if (alreadyEffective && dto.TargetValue.Value != row.TargetValue)
                throw new KpiTargetConflictException("已生效目标不可原地改值，请新增未来版本");
            KpiTargetRules.EnsureTargetPositive(dto.TargetValue.Value);
            row.TargetValue = dto.TargetValue.Value;
        }
        if (dto.EffectiveTo.HasValue)
        {
            KpiTargetRules.EnsureRange(row.EffectiveFrom, dto.EffectiveTo);
            var others = (await _store.ListActiveScopeAsync(tenantId, row.FactoryId, row.MetricCode, ct))
                .Where(x => x.Id != row.Id && x.Status == 1);
            foreach (var other in others)
            {
                if (KpiTargetRules.Overlaps(row.EffectiveFrom, dto.EffectiveTo, other.EffectiveFrom, other.EffectiveTo))
                    throw new KpiTargetConflictException("调整失效日后与其它目标重叠");
            }
            row.EffectiveTo = dto.EffectiveTo.Value.Date;
        }
        if (dto.Remark != null)
            row.Remark = dto.Remark;
        row.UpdatedBy = _userManager?.UserId;
        row.UpdateTime = DateTime.Now;
        await _store.UpdateAsync(row, ct);
        return KpiTargetRules.ToDto(row);
    }

    public async Task DisableAsync(long id, CancellationToken ct = default)
    {
        var tenantId = TenantId;
        var row = await _store.GetByIdAsync(tenantId, id, ct)
            ?? throw new KpiTargetNotFoundException("目标配置不存在");
        if (await _store.IsReferencedByDailyAsync(tenantId, id, ct))
        {
            row.Status = 0;
            row.EffectiveTo ??= DateTime.Today;
            row.UpdatedBy = _userManager.UserId;
            row.UpdateTime = DateTime.Now;
            await _store.UpdateAsync(row, ct);
            return;
        }
        row.Status = 0;
        row.UpdatedBy = _userManager.UserId;
        row.UpdateTime = DateTime.Now;
        await _store.UpdateAsync(row, ct);
    }

    public async Task<List<KpiTargetLegacyStatDto>> LegacyStatsAsync(CancellationToken ct = default)
    {
        _ = TenantId;
        _ = ct;
        return new List<KpiTargetLegacyStatDto>
        {
            new() { TargetSource = KpiTargetSnapshotSource.FormalFactory },
            new() { TargetSource = KpiTargetSnapshotSource.FormalTenantDefault },
            new() { TargetSource = KpiTargetSnapshotSource.LegacyDailyCurrent },
            new() { TargetSource = KpiTargetSnapshotSource.LegacyDailyPrior },
            new() { TargetSource = KpiTargetSnapshotSource.LegacyCode },
            new() { TargetSource = KpiTargetSnapshotSource.Missing }
        };
    }

    private async Task ClosePreviousOpenAsync(List<AdoSmartOpsKpiTargetConfig> existing, DateTime newFrom, CancellationToken ct)
    {
        var open = existing.Where(x => x.Status == 1 && x.EffectiveTo == null).OrderByDescending(x => x.EffectiveFrom).ToList();
        if (open.Count == 0)
            return;
        if (open.Count > 1)
            throw new KpiTargetDuplicateScopeException("同一工厂存在多条开放区间，拒绝静默关闭");
        var prev = open[0];
        if (prev.EffectiveFrom.Date >= newFrom)
            throw new KpiTargetConflictException("不允许自动截断未来目标");
        var closeTo = newFrom.AddDays(-1);
        if (closeTo < prev.EffectiveFrom.Date)
            throw new KpiTargetConflictException("关闭上一目标后区间无效");
        prev.EffectiveTo = closeTo;
        prev.UpdateTime = DateTime.Now;
        await _store.UpdateAsync(prev, ct);
    }

    private async Task<AdoSmartOpsKpiMaster> EnsureKpiAsync(long tenantId, string metricCode, CancellationToken ct)
    {
        var kpi = await _store.FindKpiAsync(tenantId, metricCode.Trim(), ct);
        if (kpi == null)
            throw new KpiTargetNotFoundException("指标不存在或不属于当前租户");
        return kpi;
    }

    private static void EnsureMetricCode(string? metricCode)
    {
        if (string.IsNullOrWhiteSpace(metricCode))
            throw new KpiTargetValidationException("指标编码必填");
    }

    private async Task<string?> ConfigSourceAsync(long tenantId, long configId, CancellationToken ct)
    {
        var cfg = await _store.GetByIdAsync(tenantId, configId, ct);
        return cfg?.SourceType;
    }

    public static string SerializePayload(IEnumerable<KpiTargetImportRow> rows) =>
        JsonSerializer.Serialize(rows.ToList());

    public static List<KpiTargetImportRow> DeserializePayload(string? json) =>
        string.IsNullOrWhiteSpace(json)
            ? new List<KpiTargetImportRow>()
            : JsonSerializer.Deserialize<List<KpiTargetImportRow>>(json) ?? new List<KpiTargetImportRow>();
}