;;; jao-clojure.el --- Clojure utilities             -*- lexical-binding: t; -*-

;; Copyright (C) 2025  Jose Antonio Ortega Ruiz

;; Author: Jose Antonio Ortega Ruiz <mail@jao.io>
;; Keywords: languages

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

;; This program 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 General Public License for more details.

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

;;; Commentary:

;; Helpers for clojure coding

;;; Code:

(require 'clojure-mode)
(require 'project)

;;;; Jumping between implementation and test files
(defun jao-clojure--ext-dir (prefix)
  (let* ((ext (file-name-extension buffer-file-name))
         (ext-rx (format "/%s/" ext)))
    (if (string-match-p ext-rx buffer-file-name)
        (format "%s/%s" prefix ext)
      prefix)))

(defun jao-clojure-find-current-test ()
  (save-excursion
    (and (re-search-backward
          "(deftest\\(?:\\W+^:\\w+\\)*\\W+\\b\\(.+\\)\\b" nil t)
         (match-string-no-properties 1))))

(defvar jao-clojure--src-candidates '("lib" "src" "srv" "app"))

(defun jao-clojure--test-namespace-p (ns)
  (or (string-suffix-p "-test" ns)
      (string-match "\\(.+\\)\\.\\(test\\)\\(\\..+\\)" ns)))

(defun jao-clojure-test-buffer-p ()
  (jao-clojure--test-namespace-p (clojure-find-ns)))

(defun jao-clojure--test-for (namespace sep)
  (funcall cider-test-infer-test-ns namespace))

(defun jao-clojure--infer-test-ns (ns)
  (if (jao-clojure--test-namespace-p ns)
      ns
    (jao-clojure--test-for ns ".")))

(defun jao-clojure--root () (project-root (project-current)))

(defun jao-clojure-jump-to-test ()
  "Jump from implementation to test file."
  (interactive)
  (let* ((f (format "%s/%s/%s.%s"
                    (jao-clojure--root)
                    (jao-clojure--ext-dir "test")
                    (jao-clojure--test-for (clojure-find-ns) "/")
                    (file-name-extension buffer-file-name)))
         (f (replace-regexp-in-string "-" "_" f)))
    (find-file f)))

(defun jao-clojure--implementation-for (namespace)
  (let ((n (replace-regexp-in-string "-test$" "" namespace)))
    (replace-regexp-in-string "\\.test\\." "." n)))

(defun jao-clojure--find-implementation (src)
  (let ((f (format "%s/%s/%s.%s"
                   (jao-clojure--root)
                   (jao-clojure--ext-dir src)
                   (jao-clojure--implementation-for (clojure-find-ns))
                   (file-name-extension buffer-file-name))))
    (and (file-exists-p f) f)))

(defun jao-clojure-jump-to-implementation ()
  "Jump from test file to implementation."
  (interactive)
  (let ((impl (car (seq-keep #'jao-clojure--find-implementation
                             jao-clojure--src-candidates))))
    (if impl (find-file impl) (message "No implementation file found"))))

(defun jao-clojure-other-file ()
  "Toggle between implementation and test file"
  (interactive)
  (if (jao-clojure-test-buffer-p)
      (jao-clojure-jump-to-implementation)
    (jao-clojure-jump-to-test)))

(provide 'jao-clojure)
;;; jao-clojure.el ends here