using System.ComponentModel.DataAnnotations;
using ZB.MOM.WW.OtOpcUa.Core.Abstractions;
using ZB.MOM.WW.OtOpcUa.Driver.AbLegacy.PlcFamilies;

namespace ZB.MOM.WW.OtOpcUa.Driver.AbLegacy;

/// <summary>
///     AB Legacy (PCCC) driver configuration. One instance supports N devices (SLC 500 /
///     MicroLogix / PLC-5 / LogixPccc). AbLegacy ships separately from
///     AbCip because PCCC's file-based addressing (<c>N7:0</c>) and Logix's symbolic addressing
///     (<c>Motor1.Speed</c>) pull the abstraction in different directions.
/// </summary>
public sealed class AbLegacyDriverOptions
{
    /// <summary>Gets or sets the list of PCCC devices to connect to.</summary>
    public IReadOnlyList<AbLegacyDeviceOptions> Devices { get; init; } = [];

    /// <summary>
    ///     Authored raw tags this driver serves. The deploy artifact hands each authored raw
    ///     <c>Tag</c> as a <see cref="RawTagEntry"/> (RawPath identity + driver <c>TagConfig</c> blob +
    ///     WriteIdempotent flag + owning <see cref="RawTagEntry.DeviceName"/>); the driver maps each
    ///     through <see cref="AbLegacyTagDefinitionFactory.FromTagConfig"/> into its RawPath → definition
    ///     table, routing each to its device by <see cref="RawTagEntry.DeviceName"/>. AbLegacy has no
    ///     discovery protocol — the driver serves exactly these.
    /// </summary>
    public IReadOnlyList<RawTagEntry> RawTags { get; init; } = [];

    /// <summary>
    ///     Which transport stack the driver, its Test Connect probe and the CLI use. <c>null</c> (the
    ///     <c>transport</c> key absent) means "use the default": <see cref="AbLegacyTransport.Libplctag"/> for
    ///     every family. <see cref="AbLegacyTransport.Native"/> is opt-in (final review I3: on a wire it is proven
    ///     only for N-file reads/writes and one F8 read). An explicit value always wins. The
    ///     effective transport is resolved in one place, <c>AbLegacyTransportResolver</c>.
    ///     <para>Changing this takes effect when the driver instance is RECREATED, not on
    ///     <c>ReinitializeAsync</c>: the tag factory is chosen once in the constructor and held across
    ///     Shutdown+Initialize. A deploy that changes the driver config stops and respawns the instance
    ///     (<c>DriverSpawnPlanner</c>, #516), so an operator edit does recreate it.</para>
    /// </summary>
    /// <remarks>Null is never written: an absent key IS the "use the default" encoding, so a round-trip
    ///     through any serializer (the AdminUI form included) keeps a defaulted driver defaulted rather than
    ///     pinning it to whatever the default happened to be on the day it was saved.</remarks>
    [System.Text.Json.Serialization.JsonIgnore(Condition = System.Text.Json.Serialization.JsonIgnoreCondition.WhenWritingNull)]
    public AbLegacyTransport? Transport { get; init; }

    /// <summary>Gets or sets the probe (connectivity check) options.</summary>
    public AbLegacyProbeOptions Probe { get; init; } = new();

    /// <summary>Gets or sets the default timeout for read/write operations.</summary>
    public TimeSpan Timeout { get; init; } = TimeSpan.FromSeconds(2);

    /// <summary>
    ///     Timeout for the AdminUI Test Connect probe, in seconds. The AdminUI clamps to a
    ///     60s server-side maximum; this default is what the form pre-fills for new instances.
    /// </summary>
    [Display(Name = "Probe timeout (seconds)", Description = "Connection test timeout. Default 5s.", GroupName = "Diagnostics")]
    [Range(1, 60)]
    public int ProbeTimeoutSeconds { get; init; } = 5;
}

public sealed record AbLegacyDeviceOptions(
    string HostAddress,
    AbLegacyPlcFamily PlcFamily = AbLegacyPlcFamily.Slc500,
    string? DeviceName = null);

/// <summary>
///     One PCCC-backed OPC UA variable. <paramref name="Address"/> is the canonical PCCC
///     file-address string that parses via <c>AbLegacyAddress.TryParse</c>.
/// </summary>
/// <param name="ArrayLength">
///     Element count when the tag addresses a multi-element span of a PCCC data file (e.g. an
///     <c>N7</c> integer file is inherently up to 256 words); <see langword="null"/> for a scalar.
///     A PCCC data file holds at most <see cref="AbLegacyArray.MaxElements"/> (256) elements, so a
///     value above that is clamped where it is materialised/read. <c>1</c> is a valid one-element array exposed as a <c>[1]</c> OPC UA array node.
/// </param>
public sealed record AbLegacyTagDefinition(
    string Name,
    string DeviceHostAddress,
    string Address,
    AbLegacyDataType DataType,
    bool Writable = true,
    bool WriteIdempotent = false,
    int? ArrayLength = null);

/// <summary>PCCC array-tag constants shared by the parser, discovery, and read paths.</summary>
public static class AbLegacyArray
{
    /// <summary>
    ///     Maximum element count for a single PCCC data file. The PCCC/DF1 protocol addresses a
    ///     data file element with a single byte sub-element offset, so a file holds at most 256
    ///     elements (words for N/B/I/O/S/A, 32-bit elements for L/F). Array tags clamp to this.
    /// </summary>
    public const int MaxElements = 256;
}

public sealed class AbLegacyProbeOptions
{
    /// <summary>Gets or sets a value indicating whether connectivity probing is enabled.</summary>
    public bool Enabled { get; init; } = true;

    /// <summary>Gets or sets the interval between probe attempts.</summary>
    public TimeSpan Interval { get; init; } = TimeSpan.FromSeconds(5);

    /// <summary>Gets or sets the timeout for each probe operation.</summary>
    public TimeSpan Timeout { get; init; } = TimeSpan.FromSeconds(2);

    /// <summary>Gets or sets the probe address (defaults to <c>S:0</c> — status file, first word).</summary>
    public string? ProbeAddress { get; init; } = "S:0";
}