using System.Security.Cryptography;
using System.Text;
using NozCli.Repl;
using Spectre.Console;

namespace NozCli.Commands;

public class StatusCommand : ICommand
{
    public string Name        => "status";
    public string Description => "Show diff between a local folder and the server";
    public string Usage       => "status <local-path>";

    public async Task ExecuteAsync(string[] args, ReplContext ctx)
    {
        var localPath = args.FirstOrDefault();
        if (localPath is null) { AnsiConsole.MarkupLine("[red]Usage: status <local-path>[/]"); return; }

        localPath = Path.GetFullPath(localPath);
        if (!Directory.Exists(localPath)) { AnsiConsole.MarkupLine($"[red]Not found: {localPath}[/]"); return; }

        var serverMap = ctx.NoteCache.ToDictionary(n => n.Slug, n => n.Hash ?? "");
        var localFiles = Directory.EnumerateFiles(localPath, "*.md", SearchOption.AllDirectories)
            .Where(f => !Path.GetFileName(f).StartsWith("_"));

        var added    = new List<string>();
        var modified = new List<string>();

        foreach (var file in localFiles)
        {
            var slug      = Path.GetRelativePath(localPath, file).Replace(Path.DirectorySeparatorChar, '/').Replace(".md", "");
            var markdown  = await File.ReadAllTextAsync(file);
            var localHash = Sha256(markdown);

            if (!serverMap.ContainsKey(slug))
                added.Add(slug);
            else if (serverMap[slug] != localHash)
                modified.Add(slug);
        }

        if (added.Count == 0 && modified.Count == 0)
        {
            AnsiConsole.MarkupLine("[green]✓ Everything up to date[/]");
            return;
        }

        foreach (var s in added)    AnsiConsole.MarkupLine($"  [green]+[/] {s}");
        foreach (var s in modified) AnsiConsole.MarkupLine($"  [yellow]~[/] {s}");

        AnsiConsole.MarkupLine($"\n[dim]{added.Count} new · {modified.Count} modified[/]");
    }

    private static string Sha256(string text) =>
        Convert.ToHexString(SHA256.HashData(Encoding.UTF8.GetBytes(text))).ToLower();
}