First go

will add comments in draft pull request

API/Controllers/FontController.cs

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+using System.Collections.Generic;
+using System.IO;
+using System.Threading.Tasks;
+using API.Data;
+using API.DTOs.Font;
+using API.Services;
+using API.Services.Tasks;
+using Kavita.Common;
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Mvc;
+
+namespace API.Controllers;
+
+public class FontController : BaseApiController
+{
+    private readonly IUnitOfWork _unitOfWork;
+    private readonly IFontService _fontService;
+    private readonly ITaskScheduler _taskScheduler;
+
+    public FontController(IUnitOfWork unitOfWork, IFontService fontService, ITaskScheduler taskScheduler)
+    {
+        _unitOfWork = unitOfWork;
+        _fontService = fontService;
+        _taskScheduler = taskScheduler;
+    }
+
+    [ResponseCache(CacheProfileName = "10Minute")]
+    [AllowAnonymous]
+    [HttpGet("GetFonts")]
+    public async Task<ActionResult<IEnumerable<EpubFontDto>>> GetFonts()
+    {
+        return Ok(await _unitOfWork.EpubFontRepository.GetFontDtos());
+    }
+
+    [AllowAnonymous]
+    [HttpGet("download-font")]
+    public async Task<IActionResult> GetFont(int fontId)
+    {
+        try
+        {
+            var font = await _unitOfWork.EpubFontRepository.GetFont(fontId);
+            if (font == null) return NotFound();
+            var contentType = GetContentType(font.FileName);
+            return File(await _fontService.GetContent(fontId), contentType, font.FileName);
+        }
+        catch (KavitaException ex)
+        {
+            return BadRequest(ex.Message);
+        }
+    }
+
+    [AllowAnonymous]
+    [HttpPost("scan")]
+    public IActionResult Scan()
+    {
+        _taskScheduler.ScanEpubFonts();
+        return Ok();
+    }
+
+    private string GetContentType(string fileName)
+    {
+        var extension = Path.GetExtension(fileName).ToLowerInvariant();
+        return extension switch
+        {
+            ".ttf" => "application/font-tff",
+            ".otf" => "application/font-otf",
+            ".woff" => "application/font-woff",
+            ".woff2" => "application/font-woff2",
+            _ => "application/octet-stream",
+        };
+    }
+}