;;; belf.el -- Bookshelf, ebook library management -*- lexical-binding: t -*-

;; Copyright (C) 2025  Free Software Foundation, Inc.

;; Author: Yuchen Pei <id@ypei.org>
;; Package-Requires: ((emacs "29.4"))

;; This file is part of dotted.

;; dotted is free software: you can redistribute it and/or modify it under
;; the terms of the GNU Affero General Public License as published by
;; the Free Software Foundation, either version 3 of the License, or
;; (at your option) any later version.

;; dotted is distributed in the hope that it will be useful, but WITHOUT
;; ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
;; or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Affero General
;; Public License for more details.

;; You should have received a copy of the GNU Affero General Public
;; License along with dotted.  If not, see <https://www.gnu.org/licenses/>.

;;; Commentary:

;; Bookshelf, ebook library management.

;;; Code:

(require 'tabulated-list)
(require 'infobox)

(defvar-keymap belf-mode-map
  :parent tabulated-list-mode-map
  "i" #'belf-book-infobox
  "RET" #'belf-open-book
  "o" #'belf-open-book-other-window)

(define-derived-mode belf-mode tabulated-list-mode "Bookshelf"
  "Major mode for browsing a list of books."
  (setq tabulated-list-format
        [("Authors" 25 t)
         ("Title" 48 t)
         ("Year" 4 t)])
  (setq tabulated-list-padding 2)
  (tabulated-list-init-header)
  (setq revert-buffer-function #'belf-list-refresh-contents)
  (hl-line-mode))

(defun belf-list-books ()
  (interactive)
  (let ((buf (get-buffer-create "*Bookshelf*")))
    (with-current-buffer buf
      (belf-mode)
      (belf-list-refresh-contents)
      (tabulated-list-print))
    (pop-to-buffer-same-window buf)))

(defun belf-list-refresh-contents (&rest _)
  (setq-local tabulated-list-entries (belf-parse-all-file-names)))

(defvar belf-dir "~/Documents" "Directory of books.")

(defun belf-parse-all-file-names ()
  (seq-filter
   #'identity
   (seq-map
    (lambda (f)
      (when-let ((parsed (belf-parse-file-name f)))
        (let-alist parsed
          (list f (vector .authors .title .year)))))
    (directory-files belf-dir t))))

(defun belf-parse-file-name (file-name)
  (let ((base (file-name-base file-name)))
    (when (string-match "^\\(.*?\\) - \\(.*\\) (\\([0-9]*\\))" base)
      `((authors . ,(match-string 1 base))
        (title . ,(match-string 2 base))
        (year . ,(match-string 3 base))))))

(defun belf-book-infobox ()
  (interactive)
  (infobox-exiftool (tabulated-list-get-id)))

(defun belf-open-book ()
  (interactive)
  (find-file (tabulated-list-get-id)))

(defun belf-open-book-other-window ()
  (interactive)
  (find-file-other-window (tabulated-list-get-id)))

(provide 'belf)