Google GeminiをAPI経由で使う

;;; google-gemini --- Google Gemini Utility -*- lexical-binding: t -*-

;; Copyright (C) 2024 TakesxiSximada

;; Author: TakesxiSximada <[email protected]>
;; Maintainer: TakesxiSximada <[email protected]>
;; Repository:
;; Version: 1
;; Package-Version: 20240301.0000
;; Package-Requires: ((emacs "28.0")
;; Date: 2024-03-03

;; This file is part of google-gemini.el.

;; 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 <http://www.gnu.org/licenses/>.

;;; Code:

(defvar google-gemini-api-key nil)
(defvar google-gemini-api-origin "https://generativelanguage.googleapis.com")
(defvar google-gemini-api-path "/v1beta/models/gemini-pro:generateContent")
(defvar google-gemini-api-path-with-sse (format "%s?alt=sse" google-gemini-api-path))

(defvar google-gemini-curl-config-buffer-name "*Google Gemini: cURL: config*" "")
(defvar google-gemini-curl-process-buffer-name "*Google Gemini: cURL: process*" "")
(defvar google-gemini-curl-process-error-buffer-name "*Google Gemini: cURL: error*" "")
(defvar google-gemini-curl-process nil)

(defvar-local google-gemini-curl-process-buffer-current-position nil
  "解析済みのcurlプロセスの出力の位置")

(defvar google-gemini-result-buffer-name "*Google Gemini: result*" "")

(defun google-gemini-create-curl-config (&optional text)
  (interactive "sGoogle Gemini: ")
  (with-current-buffer (get-buffer-create google-gemini-curl-config-buffer-name)
    (erase-buffer)
    (insert (format
	     "# cURL Configuration for Google Gemini API
url %s
request %s
header %s
header %s
data %s
"
	     (json-encode-string (format "%s%s" google-gemini-api-origin google-gemini-api-path-with-sse))
	     (json-encode-string "POST")
	     (json-encode-string "Content-Type: application/json")
	     (json-encode-string (format "x-goog-api-key: %s" google-gemini-api-key))
	     (json-encode-string
	      (json-encode-plist
	       `((contents . (((:parts (((:text . ,text)))))))))))))
  (with-current-buffer (get-buffer-create google-gemini-result-buffer-name)
    (goto-char (point-max))
    (insert "\n\n------------------------------\n"
	    "[ME]\n"
	    text)))

(defun google-gemini-send-request ()
  (interactive)
  (with-current-buffer (get-buffer-create google-gemini-curl-process-buffer-name)
    (erase-buffer)
    (setq google-gemini-curl-process-buffer-current-position (point-min))
    (add-hook 'after-change-functions #'google-gemini-handle-process-ouput)
    )

  (setq google-gemini-curl-process
	(make-process :name google-gemini-curl-process-buffer-name
		      :buffer google-gemini-curl-process-buffer-name
		      :stderr google-gemini-curl-process-error-buffer-name
		      :command '("/usr/bin/curl" "-K-")))

  (with-current-buffer (get-buffer google-gemini-curl-config-buffer-name)
    (process-send-string google-gemini-curl-process (buffer-string))
    (process-send-eof google-gemini-curl-process)))

(defun google-gemini-handle-process-ouput (&optional beg end len)
  (interactive)

  (with-current-buffer (get-buffer-create google-gemini-curl-process-buffer-name)
    (save-excursion
      (goto-char google-gemini-curl-process-buffer-current-position)

      (ignore-errors
	(skip-chars-forward "\r\n")
	(search-forward "data: "))

      (if-let ((sse-data (ignore-error '(json-readtable-error json-end-of-file) (json-read))))
	  (progn
	    (if-let ((text-list
		      (map 'list #'(lambda (part) (alist-get 'text part))
			   (car (map 'list #'(lambda (candidate) (alist-get 'parts (alist-get 'content candidate)))
				     (alist-get 'candidates sse-data))))))
		(progn
		  (with-current-buffer (get-buffer-create google-gemini-result-buffer-name)
		    (display-buffer (get-buffer-create google-gemini-result-buffer-name))
		    (insert "\n\n------------------------------\n"
			    "[Gemini]\n")
		    (mapc #'insert text-list))  ;; 出力用バッファに書き込み
		  (setq google-gemini-curl-process-buffer-current-position (point))  ;; 解析済みの位置を更新
		  (google-gemini-handle-process-ouput)  ;; 再帰処理により次のデータを処理する
		  )))))))

;;;###autoload
(defun google-gemini (&optional prompt)
  (interactive
   (list (read-string-from-buffer
	  "sGoogle Gemini"
	  (if (region-active-p)
	      (let ((region-text (buffer-substring-no-properties
				  (region-beginning) (region-end))))
		(with-temp-buffer
		  (insert region-text)
		  (goto-char (point-min))
		  (replace-regexp "^" "> ")
		  (buffer-string)))
	    ""))))
  (when (and prompt (not (string-blank-p prompt)))
    (google-gemini-create-curl-config prompt)
    (google-gemini-send-request)))

(provide 'google-gemini)
;; google-gemini.el ends here