using System;
using System.IO;
using System.Text.RegularExpressions;

Console.WriteLine("ModPreprocessorDefine Started");
// Console.Out.Flush();

ModPreprocessorDefine.DoSomething();

Console.WriteLine("ModPreprocessorDefine Finished");
// Console.Out.Flush();

class ModPreprocessorDefine
{
    public static void DoSomething()
    {
        // Define the path to the PreprocessorDefine.cs file
        string filePath = "Assets/Mirror/CompilerSymbols/PreprocessorDefine.cs";

        // Read the contents of the file
        string fileContents = File.ReadAllText(filePath);
        Console.WriteLine("ModPreprocessorDefine File read");
        // Console.Out.Flush();

        // Find and remove the first entry ending with "_OR_NEWER"
        fileContents = RemoveFirstOrNewerEntry(fileContents);
        Console.WriteLine("ModPreprocessorDefine Old entry removed");
        // Console.Out.Flush();

        // Find the last entry and capture the version number
        string versionNumber = GetLastVersionNumber(fileContents);
        Console.WriteLine($"ModPreprocessorDefine current version {versionNumber}");
        // Console.Out.Flush();

        // Append a new entry with the correct indentation and next version number
        fileContents = AppendNewEntry(fileContents, versionNumber);
        Console.WriteLine("ModPreprocessorDefine New entry appended");
        // Console.Out.Flush();

        // Write the modified contents back to the file
        File.WriteAllText(filePath, fileContents);
    }

    static string RemoveFirstOrNewerEntry(string input)
    {
        // Regex pattern to match the first entry ending with "_OR_NEWER"
        string pattern = @"^\s*""[^""]*_OR_NEWER""\s*,\s*$";

        // Find the first match
        Match match = Regex.Match(input, pattern, RegexOptions.Multiline);

        // If a match is found, remove the entire line
        if (match.Success)
        {
            input = input.Remove(match.Index, match.Length);
        }

        return input;
    }

    static string GetLastVersionNumber(string input)
    {
        // Regex pattern to match the last entry and capture the version number
        string pattern = @"^\s*""([^""]*)_OR_NEWER""\s*,\s*$";

        // Find all matches
        MatchCollection matches = Regex.Matches(input, pattern, RegexOptions.Multiline);

        // Capture the version number from the last match
        string versionNumber = matches.Count > 0 ? matches[matches.Count - 1].Groups[1].Value : "";

        return versionNumber;
    }

    static string AppendNewEntry(string input, string versionNumber)
    {
        // Calculate the next version number (increment by 1)
        int nextVersion = int.TryParse(versionNumber, out int currentVersion) ? currentVersion + 1 : 1;

        // Get the indentation of the "HashSet<string> defines = new HashSet<string>" line
        string indentation = GetHashSetIndentation(input);

        // Create the new entry with the correct indentation and next version number
        string newEntry = indentation + $"    \"MIRROR_{nextVersion}_OR_NEWER\"";
        Console.WriteLine($"New entry: {newEntry}");

        // Find the position of the "defines" HashSet and insert the new entry into it
        int definesStartIndex = input.IndexOf("HashSet<string> defines = new HashSet<string>");
        int definesEndIndex = input.IndexOf("};", definesStartIndex) + 1;

        // Insert the comma and new entry into the "defines" HashSet
        input = input.Remove(definesEndIndex - 2, 2); // Remove the trailing "};"
        input = input.Insert(definesEndIndex - 2, $",\n{newEntry}\n{indentation}}};");

        Console.WriteLine(input);

        return input;
    }

    static string GetHashSetIndentation(string input)
    {
        // Regex pattern to match the indentation of "HashSet<string> defines = new HashSet<string>"
        string pattern = @"^\s*HashSet<string> defines = new HashSet<string>";

        // Find the first match
        Match match = Regex.Match(input, pattern, RegexOptions.Multiline);

        // If a match is found, capture the indentation and add 4 spaces
        string indentation = match.Success ? Regex.Match(match.Value, @"^\s*").Value : "";

        return indentation;
    }
}