Split Headerer back out

This is in anticipation of making it a fully independent program. Currently, the only links to the rest of SabreTools are a few usability libraries that are mostly unnecessary. The main logic now lives as a separate library in SabreTools.Skippers.

Headerer/Program.cs

@@ -0,0 +1,187 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using Headerer.Features;
+using SabreTools.Core;
+using SabreTools.Help;
+using SabreTools.IO;
+using SabreTools.Logging;
+
+namespace Headerer
+{
+    public class Program
+    {
+        #region Static Variables
+
+        /// <summary>
+        /// Help object that determines available functionality
+        /// </summary>
+        private static FeatureSet? _help;
+
+        /// <summary>
+        /// Logging object
+        /// </summary>
+        private static readonly Logger logger = new();
+
+        #endregion
+
+        /// <summary>
+        /// Entry point for the SabreTools application
+        /// </summary>
+        /// <param name="args">String array representing command line parameters</param>
+        public static void Main(string[] args)
+        {
+            // Perform initial setup and verification
+            LoggerImpl.SetFilename(Path.Combine(PathTool.GetRuntimeDirectory(), "logs", "headerer.log"), true);
+            LoggerImpl.AppendPrefix = true;
+            LoggerImpl.LowestLogLevel = LogLevel.VERBOSE;
+            LoggerImpl.ThrowOnError = false;
+            LoggerImpl.Start();
+
+            // Create a new Help object for this program
+            _help = RetrieveHelp();
+
+            // Credits take precidence over all
+            if (new List<string>(args).Contains("--credits"))
+            {
+                FeatureSet.OutputCredits();
+                LoggerImpl.Close();
+                return;
+            }
+
+            // If there's no arguments, show help
+            if (args.Length == 0)
+            {
+                _help.OutputGenericHelp();
+                LoggerImpl.Close();
+                return;
+            }
+
+            // Get the first argument as a feature flag
+            string featureName = args[0];
+
+            // TODO: Remove this block once trimming is no longer needed
+            // TODO: Update wiki documentation ONLY after this reaches stable
+            // TODO: Re-evaluate feature flags with this change in mind
+            featureName = featureName.TrimStart('-');
+            if (args[0].StartsWith("-"))
+                logger.User($"Feature flags no longer require leading '-' characters");
+
+            // Verify that the flag is valid
+            if (!_help.TopLevelFlag(featureName))
+            {
+                logger.User($"'{featureName}' is not valid feature flag");
+                _help.OutputIndividualFeature(featureName);
+                LoggerImpl.Close();
+                return;
+            }
+
+            // Get the proper name for the feature
+            featureName = _help.GetFeatureName(featureName);
+
+            // Get the associated feature
+            BaseFeature feature = (_help[featureName] as BaseFeature)!;
+
+            // If we had the help feature first
+            if (featureName == DisplayHelp.Value || featureName == DisplayHelpDetailed.Value)
+            {
+                feature.ProcessArgs(args, _help);
+                LoggerImpl.Close();
+                return;
+            }
+
+            // Now verify that all other flags are valid
+            if (!feature.ProcessArgs(args, _help))
+            {
+                LoggerImpl.Close();
+                return;
+            }
+
+            // Set the new log level based on settings
+            LoggerImpl.LowestLogLevel = feature.LogLevel;
+
+            // If output is being redirected or we are in script mode, don't allow clear screens
+            if (!Console.IsOutputRedirected && feature.ScriptMode)
+            {
+                Console.Clear();
+                Globals.SetConsoleHeader("Headerer");
+            }
+
+            // Now process the current feature
+            Dictionary<string, Feature?> features = _help.GetEnabledFeatures();
+            bool success = false;
+            switch (featureName)
+            {
+                // No-op as these should be caught
+                case DisplayHelp.Value:
+                case DisplayHelpDetailed.Value:
+                    break;
+
+                // Require input verification
+                case Extract.Value:
+                case Restore.Value:
+                    VerifyInputs(feature.Inputs, feature);
+                    success = feature.ProcessFeatures(features);
+                    break;
+
+                // If nothing is set, show the help
+                default:
+                    _help.OutputGenericHelp();
+                    break;
+            }
+
+            // If the feature failed, output help
+            if (!success)
+            {
+                logger.Error("An error occurred during processing!");
+                _help.OutputIndividualFeature(featureName);
+            }
+
+            LoggerImpl.Close();
+            return;
+        }
+
+        /// <summary>
+        /// Generate a Help object for this program
+        /// </summary>
+        /// <returns>Populated Help object</returns>
+        private static FeatureSet RetrieveHelp()
+        {
+            // Create and add the header to the Help object
+            string barrier = "-----------------------------------------";
+            List<string> helpHeader =
+            [
+                "Headerer - Remove, store, and restore copier headers",
+                barrier,
+                "Usage: Headerer [option] [flags] [filename|dirname] ...",
+                string.Empty
+            ];
+
+            // Create the base help object with header
+            var help = new FeatureSet(helpHeader);
+
+            // Add all of the features
+            help.Add(new DisplayHelp());
+            help.Add(new DisplayHelpDetailed());
+            help.Add(new Extract());
+            help.Add(new Restore());
+
+            return help;
+        }
+
+        /// <summary>
+        /// Verify that there are inputs, show help otherwise
+        /// </summary>
+        /// <param name="inputs">List of inputs</param>
+        /// <param name="feature">Name of the current feature</param>
+        private static void VerifyInputs(List<string> inputs, BaseFeature feature)
+        {
+            if (inputs.Count == 0)
+            {
+                logger.Error("This feature requires at least one input");
+                _help?.OutputIndividualFeature(feature.Name);
+                Environment.Exit(0);
+            }
+        }
+    }
+}