using System.Data;
using System.Globalization;
using System.Text.Json;
using Admin.NET.Plugin.AiDOP.Entity.S8;
using SqlSugar;

namespace Admin.NET.Plugin.AiDOP.Service.S8.Rules;

/// <summary>
/// R2 TIMEOUT 类规则 evaluator MVP。
/// params_json 约定（首版最小集合）：
///   { dueAtField, statusField, completedStates[], objectCodeField, objectIdField, graceMinutes, exceptionTypeCode }
/// 判定：dueAt &lt;= now - graceMinutes && status NOT IN completedStates → HIT。
/// 不做严重度阶梯、不做 SLA 升级、不做事件触发。
/// </summary>
public class S8TimeoutRuleEvaluator : IS8RuleEvaluator, ITransient
{
    public const string RuleTypeCode = "TIMEOUT";
    public string RuleType => RuleTypeCode;

    private const string SqlDataSourceType = "SQL";

    private readonly SqlSugarRepository<AdoS8DataSource> _dataSourceRep;

    public S8TimeoutRuleEvaluator(SqlSugarRepository<AdoS8DataSource> dataSourceRep)
    {
        _dataSourceRep = dataSourceRep;
    }

    public async Task<List<S8RuleHit>> EvaluateAsync(
        long tenantId,
        long factoryId,
        AdoS8WatchRule rule,
        IReadOnlyList<AdoS8AlertRule> alertRules,
        CancellationToken cancellationToken = default)
    {
        var hits = new List<S8RuleHit>();

        if (string.IsNullOrWhiteSpace(rule.Expression) || string.IsNullOrWhiteSpace(rule.ParamsJson))
            return hits;

        TimeoutParams parameters;
        try { parameters = TimeoutParams.Parse(rule.ParamsJson!); }
        catch { return hits; }

        if (string.IsNullOrWhiteSpace(parameters.DueAtField)
            || string.IsNullOrWhiteSpace(parameters.StatusField)
            || string.IsNullOrWhiteSpace(parameters.ExceptionTypeCode))
            return hits;

        var dataSource = await _dataSourceRep.AsQueryable()
            .Where(x => x.Id == rule.DataSourceId
                        && x.TenantId == tenantId
                        && x.FactoryId == factoryId
                        && x.Enabled)
            .FirstAsync();
        if (dataSource == null
            || string.IsNullOrWhiteSpace(dataSource.Endpoint)
            || !string.Equals(dataSource.Type?.Trim(), SqlDataSourceType, StringComparison.OrdinalIgnoreCase))
            return hits;

        DataTable table;
        try
        {
            using var db = CreateSqlScope(dataSource.Endpoint!);
            table = await db.Ado.GetDataTableAsync(rule.Expression!);
        }
        catch
        {
            return hits;
        }

        var detectedAt = DateTime.Now;
        var threshold = detectedAt.AddMinutes(-parameters.GraceMinutes);
        var sourceObjectType = string.IsNullOrWhiteSpace(rule.SourceObjectType)
            ? rule.WatchObjectType
            : rule.SourceObjectType!;

        foreach (DataRow row in table.Rows)
        {
            var status = ReadString(row, parameters.StatusField!) ?? string.Empty;
            if (parameters.CompletedStates.Contains(status, StringComparer.OrdinalIgnoreCase))
                continue;

            var due = ReadDateTime(row, parameters.DueAtField!);
            if (due == null || due > threshold) continue;

            var objectCodeField = string.IsNullOrWhiteSpace(parameters.ObjectCodeField)
                ? "related_object_code"
                : parameters.ObjectCodeField!;
            var relatedObjectCode = ReadString(row, objectCodeField) ?? string.Empty;
            if (string.IsNullOrWhiteSpace(relatedObjectCode)) continue;

            var sourceObjectId = string.IsNullOrWhiteSpace(parameters.ObjectIdField)
                ? relatedObjectCode
                : ReadString(row, parameters.ObjectIdField!) ?? relatedObjectCode;

            var dedupKey = BuildDedupKey(tenantId, factoryId, rule.RuleCode, sourceObjectType, sourceObjectId);

            hits.Add(new S8RuleHit
            {
                SourceRuleId = rule.Id,
                SourceRuleCode = rule.RuleCode,
                SourceObjectType = sourceObjectType,
                SourceObjectId = sourceObjectId,
                RelatedObjectCode = relatedObjectCode,
                ExceptionTypeCode = parameters.ExceptionTypeCode!,
                SceneCode = rule.SceneCode,
                Severity = string.IsNullOrWhiteSpace(rule.Severity) ? "MEDIUM" : rule.Severity,
                DedupKey = dedupKey,
                SourcePayload = BuildPayload(row, due.Value, status, parameters),
                DetectedAt = detectedAt,
                Title = $"[超时] {sourceObjectType} {sourceObjectId} 已超期至 {due.Value:yyyy-MM-dd HH:mm:ss}（状态 {status}）",
                DataSourceId = dataSource.Id,
                OccurrenceDeptId = ReadLong(row, "occurrence_dept_id"),
                ResponsibleDeptId = ReadLong(row, "responsible_dept_id")
            });
        }

        return hits;
    }

    private SqlSugarScope CreateSqlScope(string connectionString)
    {
        var dbType = _dataSourceRep.Context.CurrentConnectionConfig.DbType;
        return new SqlSugarScope(new ConnectionConfig
        {
            ConfigId = $"s8-timeout-eval-{Guid.NewGuid():N}",
            DbType = dbType,
            ConnectionString = connectionString,
            InitKeyType = InitKeyType.Attribute,
            IsAutoCloseConnection = true
        });
    }

    private static string BuildDedupKey(long tenantId, long factoryId, string ruleCode, string sourceObjectType, string sourceObjectId) =>
        $"T{tenantId}:F{factoryId}:R{ruleCode}:{sourceObjectType}:{sourceObjectId}";

    private static string BuildPayload(DataRow row, DateTime dueAt, string status, TimeoutParams parameters)
    {
        var payload = new Dictionary<string, object?>(StringComparer.OrdinalIgnoreCase);
        foreach (DataColumn column in row.Table.Columns)
        {
            var value = row[column];
            payload[column.ColumnName] = value == DBNull.Value ? null : value;
        }
        payload["__ruleType"] = RuleTypeCode;
        payload["__dueAt"] = dueAt;
        payload["__status"] = status;
        payload["__graceMinutes"] = parameters.GraceMinutes;
        payload["__sourceObjectType"] = parameters.ObjectIdField;
        return JsonSerializer.Serialize(payload);
    }

    private static string? ReadString(DataRow row, string columnName)
    {
        if (string.IsNullOrWhiteSpace(columnName)) return null;
        if (!row.Table.Columns.Contains(columnName)) return null;
        var v = row[columnName];
        return v == DBNull.Value ? null : Convert.ToString(v)?.Trim();
    }

    private static DateTime? ReadDateTime(DataRow row, string columnName)
    {
        if (!row.Table.Columns.Contains(columnName)) return null;
        var v = row[columnName];
        if (v == DBNull.Value) return null;
        if (v is DateTime dt) return dt;
        return DateTime.TryParse(Convert.ToString(v, CultureInfo.InvariantCulture), out var p) ? p : null;
    }

    private static long? ReadLong(DataRow row, string columnName)
    {
        if (!row.Table.Columns.Contains(columnName)) return null;
        var v = row[columnName];
        if (v == DBNull.Value) return null;
        return long.TryParse(Convert.ToString(v, CultureInfo.InvariantCulture), out var r) ? r : null;
    }

    private sealed class TimeoutParams
    {
        public string? DueAtField { get; set; }
        public string? StatusField { get; set; }
        public List<string> CompletedStates { get; set; } = new();
        public string? ObjectCodeField { get; set; }
        public string? ObjectIdField { get; set; }
        public int GraceMinutes { get; set; }
        public string? ExceptionTypeCode { get; set; }

        public static TimeoutParams Parse(string json)
        {
            using var doc = JsonDocument.Parse(json);
            var root = doc.RootElement;
            var p = new TimeoutParams();
            if (root.TryGetProperty("dueAtField", out var v1)) p.DueAtField = v1.GetString();
            if (root.TryGetProperty("statusField", out var v2)) p.StatusField = v2.GetString();
            if (root.TryGetProperty("objectCodeField", out var v3)) p.ObjectCodeField = v3.GetString();
            if (root.TryGetProperty("objectIdField", out var v4)) p.ObjectIdField = v4.GetString();
            if (root.TryGetProperty("graceMinutes", out var v5) && v5.ValueKind == JsonValueKind.Number) p.GraceMinutes = v5.GetInt32();
            if (root.TryGetProperty("exceptionTypeCode", out var v6)) p.ExceptionTypeCode = v6.GetString();
            if (root.TryGetProperty("completedStates", out var v7) && v7.ValueKind == JsonValueKind.Array)
            {
                foreach (var s in v7.EnumerateArray())
                {
                    var str = s.GetString();
                    if (!string.IsNullOrWhiteSpace(str)) p.CompletedStates.Add(str!);
                }
            }
            return p;
        }
    }
}