using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;
using System.Security.Cryptography;
using RadicadeServer.DB;

using IOFile = System.IO.File;

namespace RadicadeServer.Custom.API
{
	[Route("custom/")]
	public class CCAPI(RecDBContext _db) : Controller
	{
		private static string GetHashAndCache(string hashName, string fileName)
		{
			if (!IOFile.Exists(hashName))
			{
				string hash = CalculateMD5(fileName);
				IOFile.WriteAllText(hashName, hash);
				return hash;
			}
			return IOFile.ReadAllText(hashName);
		}
		private static string CalculateMD5(string filename)
		{
			using (var md5 = MD5.Create())
			{
				using (var stream = IOFile.OpenRead(filename))
				{
					var hash = md5.ComputeHash(stream);
					return BitConverter.ToString(hash).Replace("-", "").ToLowerInvariant();
				}
			}
		}

		[HttpGet("all")]
		public async Task<List<CustomAddition>> GetAllContent()
		{
			return await _db.CustomContent.ToListAsync();
		}
		[HttpGet("download/{modId}/{fileId}")]
		public async Task<IActionResult> DownloadContent(long? modId, int? fileId)
		{
			if (modId == null || fileId == null) return BadRequest();

			var mod = await _db.CustomContent.FirstOrDefaultAsync(x => x.Id == modId);
			if (mod == null) return NotFound();

			var files = mod.Files.Split(";", StringSplitOptions.TrimEntries);
			if (fileId >= files.Length || fileId < 0) return BadRequest();

			string path = Path.Join(DBConfig.CDNCustom, mod.Name, files[(int)fileId]);
			if (!System.IO.File.Exists(path)) return NotFound();

			return PhysicalFile(path, "application/octet-stream", enableRangeProcessing: true);
		}
		[HttpGet("hash/{modId}/{file}")]
		public async Task<IActionResult> GetHashForMod(string modId, string file)
		{
			if (modId == null || file == null) return BadRequest();

			file = file.ToLower().Trim();

			var mod = await _db.CustomContent.FirstOrDefaultAsync(x => x.Name == modId);
			if (mod == null) return NotFound();

			var files = mod.Files.Split(";", StringSplitOptions.TrimEntries);
			var expectedFile = files.FirstOrDefault(x => x.ToLower().Trim().Contains(file));

			string path = Path.Join(DBConfig.CDNCustom, mod.Name, file);
			string hashPath = Path.Join(DBConfig.CDNCustom, mod.Name, file + "-hash");
			if (!IOFile.Exists(path)) return NotFound();

			string hash = GetHashAndCache(hashPath, path);

			return Ok(hash);
		}
	}
}