///
/// Copyright (c) 2018 Sensus Slovensko a.s.
///

using System;
using System.Collections.Generic;
using TBF.Rig.Generic;

namespace TBF.Rig.Output.DataStorage.UniDataStorageWriter
{
    /// <summary>
    /// Provides factory services for the
    /// <see cref="UniDataStorageWriter"/> component.
    /// </summary>
    /// <remarks>
    /// The factory is responsible for creating runtime
    /// <see cref="Writer"/> instances and their corresponding
    /// <see cref="WriterCfg"/> configuration objects.
    ///
    /// The concrete storage technology is not selected by the factory.
    /// Technology-specific writer selection is performed later by
    /// <see cref="Writer"/> according to the active configuration.
    ///
    /// Consequently, database write modes such as INSERT, UPDATE and
    /// stored procedure execution do not require separate component
    /// factories.
    /// </remarks>
    public class Factory : IComponentFactory
    {
        /// <summary>
        /// Gets the component class name used by the TBF component framework.
        /// </summary>
        /// <remarks>
        /// The namespace prefix is removed for backward compatibility with
        /// existing component configurations.
        /// </remarks>
        public string ClassName
        {
            get { return GetType().Namespace.Substring(8); }
        }

        /// <summary>
        /// Returns the component class name.
        /// </summary>
        /// <returns>
        /// The value of <see cref="ClassName"/>.
        /// </returns>
        public override string ToString()
        {
            return ClassName;
        }

        /// <summary>
        /// Creates a default runtime instance of the
        /// <see cref="Writer"/> component.
        /// </summary>
        /// <returns>
        /// A new <see cref="Writer"/> configured with a default
        /// <see cref="WriterCfg"/> instance.
        /// </returns>
        /// <remarks>
        /// The dummy component is primarily used by the component framework
        /// for discovery and configuration purposes.
        /// </remarks>
        public IComponent DummyComponent()
        {
            return new Writer(
                new WriterCfg("UniDataStorageWriter", this));
        }

        /// <summary>
        /// Creates a runtime <see cref="Writer"/> from an existing
        /// component configuration.
        /// </summary>
        /// <param name="cfg">
        /// Component configuration expected to be a
        /// <see cref="WriterCfg"/> instance.
        /// </param>
        /// <param name="components">
        /// Collection of already created components supplied by the
        /// component framework.
        /// </param>
        /// <returns>
        /// A new <see cref="Writer"/> instance using the supplied configuration.
        /// </returns>
        /// <exception cref="ArgumentException">
        /// Thrown when <paramref name="cfg"/> is not a valid
        /// <see cref="WriterCfg"/> instance.
        /// </exception>
        /// <remarks>
        /// The <paramref name="components"/> collection is currently not
        /// required by <see cref="Writer"/>, but remains part of the factory
        /// contract defined by <see cref="IComponentFactory"/>.
        /// </remarks>
        public IComponent GetComponent(
            IComponentCfg cfg,
            IList<IComponent> components)
        {
            WriterCfg writerCfg = cfg as WriterCfg;

            if (writerCfg == null)
            {
                throw new ArgumentException(
                    "Invalid config for UniDataStorageWriter");
            }

            return new Writer(writerCfg);
        }

        /// <summary>
        /// Creates the default configuration for the
        /// <see cref="UniDataStorageWriter"/> component.
        /// </summary>
        /// <returns>
        /// A new default <see cref="WriterCfg"/> instance.
        /// </returns>
        public IComponentCfg DefaultConfig()
        {
            return new WriterCfg(
                "UniDataStorageWriter",
                this);
        }

        /// <summary>
        /// Creates a <see cref="WriterCfg"/> instance from a persisted
        /// component database entity.
        /// </summary>
        /// <param name="component">
        /// Persisted component entity containing serialized configuration data.
        /// </param>
        /// <returns>
        /// Deserialized component configuration compatible with
        /// <see cref="Writer"/>.
        /// </returns>
        /// <remarks>
        /// Configuration deserialization is delegated to
        /// <see cref="ComponentCfgBase.CreateFromDbEntity"/>.
        /// </remarks>
        public IComponentCfg CmpntCfgFromCmpntEntity(
            Config.Entities.Component component)
        {
            return ComponentCfgBase.CreateFromDbEntity(
                WriterCfg.Serializer,
                component,
                this);
        }
    }
}