using System.Globalization;
using CliFx.Attributes;
using CliFx.Infrastructure;
using ZB.MOM.WW.OtOpcUa.Core.Abstractions;
using ZB.MOM.WW.OtOpcUa.Driver.Cli.Common;

namespace ZB.MOM.WW.OtOpcUa.Driver.TwinCAT.Cli.Commands;

/// <summary>
///     Write one value to a TwinCAT symbol. Structure writes refused — drop to driver config
///     JSON for those.
/// </summary>
[Command("write", Description = "Write a single TwinCAT symbol.")]
public sealed class WriteCommand : TwinCATTagCommandBase
{
    /// <summary>Gets the symbol path to write.</summary>
    [CommandOption("symbol", 's', Description =
        "Symbol path — same format as `read`.", IsRequired = true)]
    public string SymbolPath { get; init; } = default!;

    /// <summary>Gets the data type of the symbol value.</summary>
    [CommandOption("type", 't', Description =
        "Bool / SInt / USInt / Int / UInt / DInt / UDInt / LInt / ULInt / Real / LReal / " +
        "String / WString / Time / Date / DateTime / TimeOfDay (default DInt).")]
    public TwinCATDataType DataType { get; init; } = TwinCATDataType.DInt;

    /// <summary>Gets the value to write.</summary>
    [CommandOption("value", 'v', Description =
        "Value to write. Parsed per --type (booleans accept true/false/1/0).",
        IsRequired = true)]
    public string Value { get; init; } = default!;

    /// <inheritdoc />
    public override async ValueTask ExecuteAsync(IConsole console)
    {
        Validate();
        ConfigureLogging();
        var ct = console.RegisterCancellationHandler();

        if (DataType == TwinCATDataType.Structure)
            throw new CliFx.Exceptions.CommandException(
                "Structure (UDT) writes need an explicit member layout — drop to the driver's " +
                "config JSON for those. The CLI covers atomic types only.");

        var tagName = ReadCommand.SynthesiseTagName(SymbolPath, DataType);
        var tag = new TwinCATTagDefinition(
            Name: tagName,
            DeviceHostAddress: Gateway,
            SymbolPath: SymbolPath,
            DataType: DataType,
            Writable: true);
        var options = BuildOptions([tag]);

        var parsed = ParseValue(Value, DataType);

        await using var driver = new TwinCATDriver(options, DriverInstanceId);
        try
        {
            await driver.InitializeAsync("{}", ct);
            var results = await driver.WriteAsync([new WriteRequest(tagName, parsed)], ct);
            await console.Output.WriteLineAsync(SnapshotFormatter.FormatWrite(SymbolPath, results[0]));
        }
        finally
        {
            await driver.ShutdownAsync(CancellationToken.None);
            FlushLogging();
        }
    }

    /// <summary>
    ///     Parse <c>--value</c> per <see cref="TwinCATDataType"/>, invariant culture. Wraps
    ///     <see cref="FormatException"/> and <see cref="OverflowException"/> in a
    ///     <see cref="CliFx.Exceptions.CommandException"/> so the operator sees a clean one-line
    ///     error instead of a raw stack trace.
    /// </summary>
    /// <param name="raw">The raw string value to parse.</param>
    /// <param name="type">The target TwinCAT data type.</param>
    /// <returns>The parsed value boxed as an <see cref="object"/> matching the given <paramref name="type"/>.</returns>
    internal static object ParseValue(string raw, TwinCATDataType type)
    {
        try
        {
            return type switch
            {
                TwinCATDataType.Bool => ParseBool(raw),
                TwinCATDataType.SInt => sbyte.Parse(raw, CultureInfo.InvariantCulture),
                TwinCATDataType.USInt => byte.Parse(raw, CultureInfo.InvariantCulture),
                TwinCATDataType.Int => short.Parse(raw, CultureInfo.InvariantCulture),
                TwinCATDataType.UInt => ushort.Parse(raw, CultureInfo.InvariantCulture),
                TwinCATDataType.DInt => int.Parse(raw, CultureInfo.InvariantCulture),
                TwinCATDataType.UDInt => uint.Parse(raw, CultureInfo.InvariantCulture),
                TwinCATDataType.LInt => long.Parse(raw, CultureInfo.InvariantCulture),
                TwinCATDataType.ULInt => ulong.Parse(raw, CultureInfo.InvariantCulture),
                TwinCATDataType.Real => float.Parse(raw, CultureInfo.InvariantCulture),
                TwinCATDataType.LReal => double.Parse(raw, CultureInfo.InvariantCulture),
                TwinCATDataType.String or TwinCATDataType.WString => raw,
                // IEC 61131-3 time/date types are stored as UDINT on the wire — accept a numeric raw
                // value + let the caller handle the encoding semantics.
                TwinCATDataType.Time or TwinCATDataType.Date
                    or TwinCATDataType.DateTime or TwinCATDataType.TimeOfDay
                    => uint.Parse(raw, CultureInfo.InvariantCulture),
                _ => throw new CliFx.Exceptions.CommandException($"Unsupported DataType '{type}' for write."),
            };
        }
        catch (CliFx.Exceptions.CommandException)
        {
            throw; // already a clean user-facing error (Bool parse, Structure, unsupported type)
        }
        catch (Exception ex) when (ex is FormatException or OverflowException)
        {
            throw new CliFx.Exceptions.CommandException(
                $"Cannot parse '{raw}' as {type}: {ex.Message}");
        }
    }

    private static bool ParseBool(string raw) => raw.Trim().ToLowerInvariant() switch
    {
        "1" or "true" or "on" or "yes" => true,
        "0" or "false" or "off" or "no" => false,
        _ => throw new CliFx.Exceptions.CommandException(
            $"Boolean value '{raw}' is not recognised. Use true/false, 1/0, on/off, or yes/no."),
    };
}