using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Threading.Tasks;

namespace Logof_Client.Wiki;

public class WikiService
{
    public WikiService(string wikiRoot = null)
    {
        // prefer global wiki storage path if configured
        if (Global._instance != null && !string.IsNullOrWhiteSpace(Global._instance.wiki_storage_path))
        {
            var cfg = Global._instance.wiki_storage_path;
            WikiRootFullPath = Path.IsPathRooted(cfg)
                ? cfg
                : Path.Combine(Directory.GetCurrentDirectory(), cfg);
            WikiRoot = WikiRootFullPath;
        }
        else
        {
            if (wikiRoot == null)
                wikiRoot = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData),
                    "logofclient",
                    "wiki");
            WikiRoot = wikiRoot;
            WikiRootFullPath = Path.Combine(Directory.GetCurrentDirectory(), wikiRoot);
        }
    }

    public string WikiRoot { get; }
    public string WikiRootFullPath { get; }

    public List<WikiItem> GetRootItems()
    {
        var list = new List<WikiItem>();

        if (!Directory.Exists(WikiRootFullPath)) return list;

        var dirInfo = new DirectoryInfo(WikiRootFullPath);

        // Add folders
        foreach (var dir in dirInfo.GetDirectories()) list.Add(BuildFolderItem(dir));

        // Add files in root
        foreach (var file in dirInfo.GetFiles("*.md"))
            list.Add(new WikiItem { Name = file.Name, Path = file.FullName, IsFolder = false });

        return list.OrderBy(i => i.IsFolder ? 0 : 1).ToList();
    }

    private WikiItem BuildFolderItem(DirectoryInfo dir)
    {
        var node = new WikiItem { Name = dir.Name, Path = dir.FullName, IsFolder = true };

        foreach (var subdir in dir.GetDirectories()) node.Children.Add(BuildFolderItem(subdir));

        foreach (var file in dir.GetFiles("*.md"))
            node.Children.Add(new WikiItem { Name = file.Name, Path = file.FullName, IsFolder = false });

        return node;
    }

    public Task<string?> LoadFileContentAsync(string path)
    {
        if (!File.Exists(path)) return Task.FromResult<string?>(null);
        return File.ReadAllTextAsync(path);
    }
}