using SQLInsight.Connectivity;
using SQLInsight.Repository;

namespace SQLInsight.Agent;

public sealed class AgentOptions
{
    public const string SectionName = "SQLInsight";

    /// <summary>How often the scheduler checks whether collectors are due.</summary>
    public TimeSpan Tick { get; set; } = TimeSpan.FromSeconds(15);

    /// <summary>How many instances are checked at the same time.</summary>
    public int MaxParallelInstances { get; set; } = 4;

    /// <summary>Overrides of collector intervals by collector name, e.g. <c>"blocking": "00:00:30"</c>.</summary>
    public IDictionary<string, TimeSpan> CollectorIntervals { get; } = new Dictionary<string, TimeSpan>(StringComparer.OrdinalIgnoreCase);

    public RepositoryOptions Repository { get; set; } = new();

    public RetentionOptions Retention { get; set; } = new();

    public PrivilegeOptions Privileges { get; set; } = new();

    public TopSqlOptions TopSql { get; set; } = new();

    public ErrorLogOptions ErrorLog { get; set; } = new();

    public ActivityOptions Activity { get; set; } = new();

    public TempdbOptions Tempdb { get; set; } = new();

    public DynamicsAxOptions DynamicsAx { get; set; } = new();

    public IList<MonitoredInstance> Instances { get; } = [];
}

public sealed class RepositoryOptions
{
    /// <summary>
    /// Connection string to the SQLInsight repository database. Use a SQL Server 2016+ instance other than the
    /// ones being monitored.
    /// </summary>
    public string? ConnectionString { get; set; }
}

public sealed class MonitoredInstance
{
    /// <summary>Stable name shown in the UI and used as the key in the repository and SQLInsight Hub.</summary>
    public string Name { get; set; } = string.Empty;

    public string Server { get; set; } = string.Empty;
    public AuthenticationMode Authentication { get; set; } = AuthenticationMode.Windows;
    public string? UserName { get; set; }
    public string? Password { get; set; }
    public ConnectionProvider Provider { get; set; } = ConnectionProvider.Auto;
    public EncryptionMode Encryption { get; set; } = EncryptionMode.Mandatory;
    public bool TrustServerCertificate { get; set; }
    public string OdbcDriver { get; set; } = "ODBC Driver 18 for SQL Server";

    /// <summary>Entra tenant id, for EntraServicePrincipal.</summary>
    public string? TenantId { get; set; }

    public ConnectionTarget ToTarget() => new()
    {
        Server = Server,
        Authentication = Authentication,
        UserName = UserName,
        Password = Password,
        Provider = Provider,
        Encryption = Encryption,
        TrustServerCertificate = TrustServerCertificate,
        OdbcDriver = OdbcDriver,
        TenantId = TenantId,
    };
}

/// <summary>The privilege audit (sysadmin and the other elevated server rights).</summary>
public sealed class PrivilegeOptions
{
    /// <summary>More people and accounts with sysadmin than this is a finding (SQLI-SEC-002).</summary>
    public int MaxSysadminAccounts { get; set; } = 3;

    /// <summary>Unfold Windows groups with server rights to the people in them, by asking Active Directory (Windows only).</summary>
    public bool ExpandWindowsGroups { get; set; } = true;
}

/// <summary>Top SQL (the heaviest statements).</summary>
public sealed class TopSqlOptions
{
    /// <summary>
    /// A statement whose CPU time is more than this share of the time it has been in the plan cache runs almost
    /// constantly (SQLI-PERF-…); 100 means one CPU core all the time.
    /// </summary>
    public double ActivityThresholdPercent { get; set; } = 50;
}

/// <summary>The SQL Server error log.</summary>
public sealed class ErrorLogOptions
{
    /// <summary>Failed logins within one collection (5 minutes) before it is a finding (SQLI-LOG-004).</summary>
    public int LoginFailureBurst { get; set; } = 20;
}

/// <summary>Open transactions and long-running statements.</summary>
public sealed class ActivityOptions
{
    /// <summary>A transaction open longer than this (minutes) is a finding (SQLI-TRAN-001); six times as long is High.</summary>
    public int TransactionMinutes { get; set; } = 10;

    /// <summary>A transaction holding more transaction log than this (MB) is a finding (SQLI-TRAN-002).</summary>
    public int TransactionLogMegabytes { get; set; } = 1024;

    /// <summary>A user statement running longer than this (minutes) is a finding (SQLI-REQ-001).</summary>
    public int RequestMinutes { get; set; } = 15;
}

/// <summary>tempdb and the version store.</summary>
public sealed class TempdbOptions
{
    /// <summary>The version store above this (MB) is a finding (SQLI-TEMP-001).</summary>
    public int VersionStoreMegabytes { get; set; } = 1024;

    /// <summary>A session using more tempdb than this (MB) for 15 minutes is a finding (SQLI-TEMP-003).</summary>
    public int SessionMegabytes { get; set; } = 1024;
}

/// <summary>
/// The Dynamics AX checks (SQLInsight:DynamicsAx). They only run in databases recognised as AX and chosen for monitoring;
/// the data checks need the optional read access (db/permissions/grant-dynamics-ax-read.sql).
/// </summary>
public sealed class DynamicsAxOptions
{
    /// <summary>A waiting batch job this many minutes past its planned start is late (SQLI-AX-003).</summary>
    public int BatchLateMinutes { get; set; } = 30;

    /// <summary>Late by this many hours: in practice never started (High).</summary>
    public int BatchNeverStartedHours { get; set; } = 24;

    /// <summary>A batch job executing this many hours is stuck (SQLI-AX-004).</summary>
    public int BatchStuckHours { get; set; } = 6;

    /// <summary>Running this many times longer than its own 90th percentile is unusually long (SQLI-AX-002).</summary>
    public double BatchLongRunningFactor { get; set; } = 2.0;

    /// <summary>…but never for runs shorter than this (minutes).</summary>
    public int BatchLongRunningMinimumMinutes { get; set; } = 10;

    /// <summary>Earlier runs needed before a job is compared with its own history.</summary>
    public int BatchHistoryMinimumRuns { get; set; } = 5;

    /// <summary>A run that failed within this many hours is reported (SQLI-AX-001).</summary>
    public int BatchFailedLookbackHours { get; set; } = 24;

    /// <summary>A number sequence used more than this (percent) is a finding (SQLI-AX-005).</summary>
    public double NumberSequenceWarnPercent { get; set; } = 80;

    /// <summary>…and High from this.</summary>
    public double NumberSequenceCriticalPercent { get; set; } = 95;

    /// <summary>Forecast to run out within this many days is a finding (number sequences and 64-bit RecId).</summary>
    public int ForecastWarnDays { get; set; } = 90;

    /// <summary>…and High within this many days.</summary>
    public int ForecastCriticalDays { get; set; } = 30;

    /// <summary>AX 3.0's 32-bit RecId: a finding from this share of the int range (SQLI-AX-009).</summary>
    public double RecId32WarnPercent { get; set; } = 50;

    /// <summary>…and Critical from this.</summary>
    public double RecId32CriticalPercent { get; set; } = 75;

    /// <summary>AX 3.0: forecast to run out within this many days is a finding, Critical within half.</summary>
    public int RecId32ForecastDays { get; set; } = 730;

    /// <summary>64-bit RecId (or a lowered MAXVAL): a finding from this share.</summary>
    public double RecId64WarnPercent { get; set; } = 80;

    /// <summary>An AX session blocking others this many seconds is reported with its AX user (SQLI-AX-010).</summary>
    public int BlockingSeconds { get; set; } = 30;

    /// <summary>How many days back the forecasts look.</summary>
    public int ForecastBasisDays { get; set; } = 30;

    /// <summary>The AOS's time zone (Windows or IANA id) for Axapta 3.0/4.0's local times; empty: the agent's own zone when it matches the SQL Server.</summary>
    public string? LocalTimeZone { get; set; }

    public Core.DynamicsAx.AxThresholds ToThresholds() => new()
    {
        BatchLateMinutes = Math.Max(1, BatchLateMinutes),
        BatchNeverStartedHours = Math.Max(1, BatchNeverStartedHours),
        BatchStuckHours = Math.Max(1, BatchStuckHours),
        BatchLongRunningFactor = Math.Max(1.1, BatchLongRunningFactor),
        BatchLongRunningMinimumMinutes = Math.Max(1, BatchLongRunningMinimumMinutes),
        BatchHistoryMinimumRuns = Math.Clamp(BatchHistoryMinimumRuns, 1, Core.DynamicsAx.AxBatchHistory.RunsKept),
        BatchFailedLookbackHours = Math.Max(1, BatchFailedLookbackHours),
        NumberSequenceWarnPercent = Math.Clamp(NumberSequenceWarnPercent, 1, 100),
        NumberSequenceCriticalPercent = Math.Clamp(NumberSequenceCriticalPercent, 1, 100),
        ForecastWarnDays = Math.Max(1, ForecastWarnDays),
        ForecastCriticalDays = Math.Max(1, ForecastCriticalDays),
        RecId32WarnPercent = Math.Clamp(RecId32WarnPercent, 1, 100),
        RecId32CriticalPercent = Math.Clamp(RecId32CriticalPercent, 1, 100),
        RecId32ForecastDays = Math.Max(1, RecId32ForecastDays),
        RecId64WarnPercent = Math.Clamp(RecId64WarnPercent, 1, 100),
        BlockingSeconds = Math.Max(1, BlockingSeconds),
        ForecastBasisDays = Math.Clamp(ForecastBasisDays, 2, 365),
        LocalTimeZone = string.IsNullOrWhiteSpace(LocalTimeZone) ? null : LocalTimeZone.Trim(),
    };
}