khoj/src/interface/emacs/khoj.el

;;; khoj.el --- AI copilot for your Second Brain -*- lexical-binding: t -*-

;; Copyright (C) 2021-2023 Khoj Inc.

;; Author: Debanjum Singh Solanky <debanjum@khoj.dev>
;;         Saba Imran <saba@khoj.dev>
;; Description: An AI copilot for your Second Brain
;; Keywords: search, chat, org-mode, outlines, markdown, pdf, image
;; Version: 1.5.1
;; Package-Requires: ((emacs "27.1") (transient "0.3.0") (dash "2.19.1"))
;; URL: https://github.com/khoj-ai/khoj/tree/master/src/interface/emacs

;; This file is NOT part of GNU Emacs.

;;; License:

;; 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/>.

;;; Commentary:

;; Create an AI copilot to your `org-mode', `markdown' notes,
;; PDFs and images. The copilot exposes 2 modes, search and chat:
;;
;; Chat provides faster answers, iterative discovery and assisted
;; creativity. It requires your OpenAI API key to access GPT models
;;
;; Search allows natural language, incremental and local search.
;; It relies on AI models that run locally on your machine.
;;
;; Quickstart
;; -------------
;; 1. Install khoj.el from MELPA Stable
;;    (use-package khoj :pin melpa-stable :bind ("C-c s" . 'khoj))
;; 2. Start khoj from Emacs
;;    C-c s or M-x khoj
;;
;; See the repository docs for detailed setup and configuration steps.

;;; Code:

(require 'url)
(require 'json)
(require 'transient)
(require 'outline)
(require 'dash)
(require 'org)

(eval-when-compile (require 'subr-x)) ;; for string-trim before Emacs 28.2


;; -------------------------
;; Khoj Static Configuration
;; -------------------------

(defcustom khoj-server-url "https://app.khoj.dev"
  "Location of Khoj API server."
  :group 'khoj
  :type 'string)

(defcustom khoj-server-is-local t
  "Is Khoj server on local machine?."
  :group 'khoj
  :type 'boolean)

(defcustom khoj-image-width 156
  "Width of rendered images returned by Khoj."
  :group 'khoj
  :type 'integer)

(defcustom khoj-image-height 156
  "Height of rendered images returned by Khoj."
  :group 'khoj
  :type 'integer)

(defcustom khoj-results-count 5
  "Number of results to show in search and use for chat responses."
  :group 'khoj
  :type 'integer)

(defcustom khoj-search-on-idle-time 0.3
  "Idle time (in seconds) to wait before triggering search."
  :group 'khoj
  :type 'number)

(defcustom khoj-api-key nil
  "API Key to your Khoj. Default at https://app.khoj.dev/config#clients."
  :group 'khoj
  :type 'string)

(defcustom khoj-auto-index t
  "Should content be automatically re-indexed every `khoj-index-interval' seconds."
  :group 'khoj
  :type 'boolean)

(defcustom khoj-index-interval 3600
  "Interval (in seconds) to wait before updating content index."
  :group 'khoj
  :type 'number)

(defcustom khoj-default-content-type "org"
  "The default content type to perform search on."
  :group 'khoj
  :type '(choice (const "org")
                 (const "markdown")
                 (const "image")
                 (const "pdf")))


;; --------------------------
;; Khoj Dynamic Configuration
;; --------------------------

(defvar khoj--minibuffer-window nil
  "Minibuffer window used to enter query.")

(defconst khoj--query-prompt "🏮 Khoj: "
  "Query prompt shown in the minibuffer.")

(defconst khoj--search-buffer-name "*🏮 Khoj Search*"
  "Name of buffer to show search results from Khoj.")

(defconst khoj--chat-buffer-name "*🏮 Khoj Chat*"
  "Name of chat buffer for Khoj.")

(defvar khoj--content-type "org"
  "The type of content to perform search on.")

(defvar khoj--search-on-idle-timer nil
  "Idle timer to trigger incremental search.")

(defvar khoj--index-timer nil
  "Timer to trigger content indexing.")

(defvar khoj--indexed-files '()
  "Files that were indexed in previous content indexing run.")

(declare-function org-element-property "org-mode" (PROPERTY ELEMENT))
(declare-function org-element-type "org-mode" (ELEMENT))
(declare-function markdown-mode "markdown-mode" ())
(declare-function which-key--show-keymap "which-key" (KEYMAP-NAME KEYMAP &optional PRIOR-ARGS ALL
NO-PAGING FILTER))

(defun khoj--keybindings-info-message ()
  "Show available khoj keybindings in-context, when khoj invoked."
  (let ((enabled-content-types (khoj--get-enabled-content-types)))
    (concat
     "
     Set Content Type
-------------------------\n"
     (when (member 'markdown enabled-content-types)
       "C-x m  | markdown\n")
     (when (member 'org enabled-content-types)
       "C-x o  | org-mode\n")
     (when (member 'image enabled-content-types)
       "C-x i  | image\n")
     (when (member 'pdf enabled-content-types)
       "C-x p  | pdf\n"))))

(defvar khoj--rerank nil "Track when re-rank of results triggered.")
(defvar khoj--reference-count 0 "Track number of references currently in chat bufffer.")
(defun khoj--search-markdown () "Set content-type to `markdown'." (interactive) (setq khoj--content-type "markdown"))
(defun khoj--search-org () "Set content-type to `org-mode'." (interactive) (setq khoj--content-type "org"))
(defun khoj--search-images () "Set content-type to image." (interactive) (setq khoj--content-type "image"))
(defun khoj--search-pdf () "Set content-type to pdf." (interactive) (setq khoj--content-type "pdf"))
(defun khoj--improve-rank () "Use cross-encoder to rerank search results." (interactive) (khoj--incremental-search t))
(defun khoj--make-search-keymap (&optional existing-keymap)
  "Setup keymap to configure Khoj search. Build of EXISTING-KEYMAP when passed."
  (let ((enabled-content-types (khoj--get-enabled-content-types))
        (kmap (or existing-keymap (make-sparse-keymap))))
    (define-key kmap (kbd "C-c RET") #'khoj--improve-rank)
    (when (member 'markdown enabled-content-types)
      (define-key kmap (kbd "C-x m") #'khoj--search-markdown))
    (when (member 'org enabled-content-types)
      (define-key kmap (kbd "C-x o") #'khoj--search-org))
    (when (member 'image enabled-content-types)
      (define-key kmap (kbd "C-x i") #'khoj--search-images))
    (when (member 'pdf enabled-content-types)
      (define-key kmap (kbd "C-x p") #'khoj--search-pdf))
    kmap))

(defvar khoj--keymap nil "Track Khoj keymap in this variable.")
(defun khoj--display-keybinding-info ()
  "Display information on keybindings to customize khoj search.
Use `which-key` if available, else display simple message in echo area"
  (if (fboundp 'which-key-show-full-keymap)
      (let ((khoj--keymap (khoj--make-search-keymap)))
        (which-key--show-keymap (symbol-name 'khoj--keymap)
                                (symbol-value 'khoj--keymap)
                                nil t t))
    (message "%s" (khoj--keybindings-info-message))))


;; ----------------
;; Khoj Setup
;; ----------------
(defcustom khoj-server-command
  (or (executable-find "khoj")
      (executable-find "khoj.exe")
      "khoj")
  "Command to interact with Khoj server."
  :type 'string
  :group 'khoj)

(defcustom khoj-server-args '()
  "Arguments to pass to Khoj server on startup."
  :type '(repeat string)
  :group 'khoj)

(defcustom khoj-server-python-command
  (if (equal system-type 'windows-nt)
      (or (executable-find "py")
          (executable-find "pythonw")
          "python")
    (if (executable-find "python")
        "python"
      ;; Fallback on systems where python is not
      ;; symlinked to python3.
      "python3"))
  "The Python interpreter used for the Khoj server.

Khoj will try to use the system interpreter if it exists. If you wish
to use a specific python interpreter (from a virtual environment
for example), set this to the full interpreter path."
  :type '(choice (const :tag "python" "python")
                 (const :tag "python3" "python3")
                 (const :tag "pythonw (Python on Windows)" "pythonw")
                 (const :tag "py (other Python on Windows)" "py")
                 (string :tag "Other"))
  :safe (lambda (val)
          (member val '("python" "python3" "pythonw" "py")))
  :group 'khoj)

(defcustom khoj-org-files nil
  "List of org-files to index on khoj server."
  :type '(repeat string)
  :group 'khoj)

(defcustom khoj-org-directories nil
  "List of directories with `org-mode' files to index on khoj server."
  :type '(repeat string)
  :group 'khoj)

(make-obsolete-variable 'khoj-org-directories 'khoj-index-directories "1.2.0" 'set)
(make-obsolete-variable 'khoj-org-files 'khoj-index-files "1.2.0" 'set)

(defcustom khoj-index-files (org-agenda-files t t)
  "List of org, markdown, pdf and other plaintext to index on khoj server."
  :type '(repeat string)
  :group 'khoj)

(defcustom khoj-index-directories nil
  "List of directories with org, markdown, pdf and other plaintext files to index on khoj server."
  :type '(repeat string)
  :group 'khoj)

(defcustom khoj-auto-setup t
  "Automate install, configure and start of khoj server.
Auto invokes setup steps on calling main entrypoint."
  :type 'string
  :group 'khoj)

(defvar khoj--server-process nil "Track khoj server process.")
(defvar khoj--server-name "*khoj-server*" "Track khoj server buffer.")
(defvar khoj--server-ready? nil "Track if khoj server is ready to receive API calls.")
(defvar khoj--server-configured? t "Track if khoj server is configured to receive API calls.")
(defvar khoj--progressbar '(🌑 🌘 🌗 🌖 🌕 🌔 🌓 🌒) "Track progress via moon phase animations.")

(defun khoj--server-get-version ()
  "Return the khoj server version."
  (with-temp-buffer
    (call-process khoj-server-command nil t nil "--version")
    (goto-char (point-min))
    (re-search-forward "\\([a-z0-9.]+\\)")
    (match-string 1)))

(defun khoj--server-install-upgrade ()
  "Install or upgrade the khoj server."
  (with-temp-buffer
    (message "khoj.el: Installing server...")
    (if (/= (apply #'call-process khoj-server-python-command
                   nil t nil
                   "-m" "pip" "install" "--upgrade"
                   '("khoj-assistant"))
            0)
        (message "khoj.el: Failed to install Khoj server. Please install it manually using pip install `khoj-assistant'.\n%s" (buffer-string))
      (message "khoj.el: Installed and upgraded Khoj server version: %s" (khoj--server-get-version)))))

(defun khoj--server-start ()
  "Start the khoj server."
  (interactive)
  (let* ((url-parts (split-string (cadr (split-string khoj-server-url "://")) ":"))
         (server-host (nth 0 url-parts))
         (server-port (or (nth 1 url-parts) "80"))
         (server-args (append khoj-server-args
                              (list (format "--host=%s" server-host)
                                    (format "--port=%s" server-port)))))
    (message "khoj.el: Starting server at %s %s..." server-host server-port)
    (setq khoj--server-process
          (make-process
           :name khoj--server-name
           :buffer khoj--server-name
           :command (append (list khoj-server-command) server-args)
           :sentinel (lambda (_ event)
                       (message "khoj.el: khoj server stopped with: %s" event)
                       (setq khoj--server-ready? nil))
           :filter (lambda (process msg)
                     (cond ((string-match (format "Uvicorn running on %s" khoj-server-url) msg)
                            (progn
                              (setq khoj--server-ready? t)))
                           ((string-match "Batches:  " msg)
                            (when (string-match "\\([0-9]+\\.[0-9]+\\|\\([0-9]+\\)\\)%?" msg)
                              (message "khoj.el: %s updating index %s"
                                       (nth (% (string-to-number (match-string 1 msg)) (length khoj--progressbar)) khoj--progressbar)
                                       (match-string 0 msg)))
                            (setq khoj--server-configured? nil))
                           ((and (not khoj--server-configured?)
                                 (string-match "Processor reconfigured via API" msg))
                            (setq khoj--server-configured? t))
                           ((and (not khoj--server-ready?)
                                 (or (string-match "configure.py" msg)
                                     (string-match "main.py" msg)
                                     (string-match "api.py" msg)))
                            (dolist (line (split-string msg "\n"))
                              (when (string-match "  " line)
                                (message "khoj.el: %s" (nth 1 (split-string line "  " t " *")))))))
                     ;; call default process filter to write output to process buffer
                     (internal-default-process-filter process msg))))
    (set-process-query-on-exit-flag khoj--server-process nil)
    (when (not khoj--server-process)
        (message "khoj.el: Failed to start Khoj server. Please start it manually by running `khoj' on terminal.\n%s" (buffer-string)))))

(defun khoj--server-started? ()
  "Check if the khoj server has been started."
  ;; check for when server process handled from within emacs
  (if (and khoj--server-process
           (process-live-p khoj--server-process))
      t
    ;; else general check via ping to khoj-server-url
    (if (ignore-errors
          (url-retrieve-synchronously (format "%s/api/health" khoj-server-url)))
        ;; Successful ping to non-emacs khoj server indicates it is started and ready.
        ;; So update ready state tracker variable (and implicitly return true for started)
        (setq khoj--server-ready? t)
      nil)))

(defun khoj--server-restart ()
  "Restart the khoj server."
  (interactive)
  (khoj--server-stop)
  (khoj--server-start))

(defun khoj--server-stop ()
  "Stop the khoj server."
  (interactive)
  (when (khoj--server-started?)
    (message "khoj.el: Stopping server...")
    (kill-process khoj--server-process)
    (message "khoj.el: Stopped server.")))

(defun khoj--server-setup ()
  "Install and start the khoj server, if required."
  (interactive)
  ;; Install khoj server, if not available but expected on local machine
  (when (and khoj-server-is-local
             (or (not (executable-find khoj-server-command))
                 (not (khoj--server-get-version))))
      (khoj--server-install-upgrade))
  ;; Start khoj server if not already started
  (when (not (khoj--server-started?))
    (khoj--server-start)))

(defun khoj-setup (&optional interact)
  "Install and start Khoj server. Get permission if INTERACT is non-nil."
  (interactive "p")
  ;; Setup khoj server if not running
  (let* ((not-started (not (khoj--server-started?)))
         (permitted (if (and not-started interact)
                        (y-or-n-p "Could not connect to Khoj server. Should I install, start it for you?")
                      t)))
    ;; If user permits setup of khoj server from khoj.el
    (when permitted
      ; Install, start server if server not running
      (when not-started
        (khoj--server-setup))

      ;; Wait until server is ready
      ;; As server can be started but not ready to use
      (while (not khoj--server-ready?)
        (sit-for 0.5)))))


;; -------------------
;; Khoj Index Content
;; -------------------

(defun khoj--server-index-files (&optional force content-type file-paths)
  "Send files at `FILE-PATHS' to the Khoj server to index for search and chat.
`FORCE' re-indexes all files of `CONTENT-TYPE' even if they are already indexed."
  (interactive)
  (let* ((boundary (format "-------------------------%d" (random (expt 10 10))))
         ;; Use `khoj-index-directories', `khoj-index-files' when set, else fallback to `khoj-org-directories', `khoj-org-files'
         ;; This is a temporary change. `khoj-org-directories', `khoj-org-files' are deprecated. They will be removed in a future release
         (content-directories (or khoj-index-directories khoj-org-directories))
         (content-files (or khoj-index-files khoj-org-files))
         (files-to-index (or file-paths
                             (append (mapcan (lambda (dir) (directory-files-recursively dir "\\.\\(org\\|md\\|markdown\\|pdf\\|txt\\|rst\\|xml\\|htm\\|html\\)$")) content-directories) content-files)))
         (type-query (if (or (equal content-type "all") (not content-type)) "" (format "t=%s" content-type)))
         (inhibit-message t)
         (message-log-max nil))
    (let ((url-request-method "POST")
          (url-request-data (khoj--render-files-as-request-body files-to-index khoj--indexed-files boundary))
          (url-request-extra-headers `(("content-type" . ,(format "multipart/form-data; boundary=%s" boundary))
                                       ("Authorization" . ,(format "Bearer %s" khoj-api-key)))))
      (with-current-buffer
          (url-retrieve (format "%s/api/v1/index/update?%s&force=%s&client=emacs" khoj-server-url type-query (or force "false"))
                        ;; render response from indexing API endpoint on server
                        (lambda (status)
                          (if (not status)
                              (message "khoj.el: %scontent index %supdated" (if content-type (format "%s " content-type) "all ") (if force "force " ""))
                            (progn
                              (khoj--delete-open-network-connections-to-server)
                              (with-current-buffer (current-buffer)
                                (search-forward "\n\n" nil t)
                                (message "khoj.el: Failed to %supdate %scontent index. Status: %s%s"
                                         (if force "force " "")
                                         (if content-type (format "%s " content-type) "all")
                                         (string-trim (format "%s %s" (nth 1 (nth 1 status)) (nth 2 (nth 1 status))))
                                         (if (> (- (point-max) (point)) 0) (format ". Response: %s" (string-trim (buffer-substring-no-properties (point) (point-max)))) ""))))))
                        nil t t)))
    (setq khoj--indexed-files files-to-index)))

(defun khoj--render-files-as-request-body (files-to-index previously-indexed-files boundary)
  "Render `FILES-TO-INDEX', `PREVIOUSLY-INDEXED-FILES' as multi-part form body.
Use `BOUNDARY' to separate files. This is sent to Khoj server as a POST request."
  (with-temp-buffer
    (set-buffer-multibyte nil)
    (insert "\n")
    (dolist (file-to-index files-to-index)
      ;; find file content-type. Choose from org, markdown, pdf, plaintext
      (let ((content-type (cond ((string-match "\\.org$" file-to-index) "text/org")
                                ((string-match "\\.\\(md\\|markdown\\)$" file-to-index) "text/markdown")
                                ((string-match "\\.pdf$" file-to-index) "application/pdf")
                                (t "text/plain"))))
      (insert (format "--%s\r\n" boundary))
      (insert (format "Content-Disposition: form-data; name=\"files\"; filename=\"%s\"\r\n" file-to-index))
      (insert (format "Content-Type: %s\r\n\r\n" content-type))
      (insert (with-temp-buffer
                (insert-file-contents-literally file-to-index)
                (buffer-string)))
      (insert "\r\n")))
    (dolist (file-to-index previously-indexed-files)
      (when (not (member file-to-index files-to-index))
        ;; find file content-type. Choose from org, markdown, pdf, plaintext
        (let ((content-type (cond ((string-match "\\.org$" file-to-index) "text/org")
                                  ((string-match "\\.\\(md\\|markdown\\)$" file-to-index) "text/markdown")
                                  ((string-match "\\.pdf$" file-to-index) "application/pdf")
                                  (t "text/plain"))))
          (insert (format "--%s\r\n" boundary))
          (insert (format "Content-Disposition: form-data; name=\"files\"; filename=\"%s\"\r\n" file-to-index))
          (insert "Content-Type: text/org\r\n\r\n")
          (insert "")
          (insert "\r\n"))))
    (insert (format "--%s--\r\n" boundary))
    (buffer-string)))

;; Cancel any running indexing timer, first
(when khoj--index-timer
    (cancel-timer khoj--index-timer))
;; Send files to index on server every `khoj-index-interval' seconds
(when khoj-auto-index
  (setq khoj--index-timer
        (run-with-timer 60 khoj-index-interval 'khoj--server-index-files)))


;; -------------------------------------------
;; Render Response from Khoj server for Emacs
;; -------------------------------------------

(defun khoj--extract-entries-as-markdown (json-response query)
  "Convert JSON-RESPONSE, QUERY from API to markdown entries."
  (thread-last
    json-response
    ;; Extract and render each markdown entry from response
    (mapcar (lambda (json-response-item)
              (thread-last
                ;; Extract markdown entry from each item in json response
                (cdr (assoc 'entry json-response-item))
                ;; Format markdown entry as a string
                (format "%s\n\n")
                ;; Standardize results to 2nd level heading for consistent rendering
                (replace-regexp-in-string "^\#+" "##"))))
    ;; Render entries into markdown formatted string with query set as as top level heading
    (format "# %s\n%s" query)
    ;; remove leading (, ) or SPC from extracted entries string
    (replace-regexp-in-string "^[\(\) ]" "")))

(defun khoj--extract-entries-as-org (json-response query)
  "Convert JSON-RESPONSE, QUERY from API to `org-mode' entries."
  (thread-last
    json-response
    ;; Extract and render each org-mode entry from response
    (mapcar (lambda (json-response-item)
              (thread-last
                ;; Extract org entry from each item in json response
                (cdr (assoc 'entry json-response-item))
                ;; Format org entry as a string
                (format "%s")
                ;; Standardize results to 2nd level heading for consistent rendering
                (replace-regexp-in-string "^\*+" "**"))))
    ;; Render entries into org formatted string with query set as as top level heading
    (format "* %s\n%s\n" query)
    ;; remove leading (, ) or SPC from extracted entries string
    (replace-regexp-in-string "^[\(\) ]" "")))

(defun khoj--extract-entries-as-pdf (json-response query)
  "Convert QUERY, JSON-RESPONSE from API with PDF results to `org-mode' entries."
  (thread-last
    json-response
    ;; Extract and render each pdf entry from response
    (mapcar (lambda (json-response-item)
              (thread-last
                ;; Extract pdf entry from each item in json response
                (cdr (assoc 'compiled (assoc 'additional json-response-item)))
                ;; Format pdf entry as a org entry string
                (format "** %s\n\n"))))
    ;; Render entries into org formatted string with query set as as top level heading
    (format "* %s\n%s\n" query)
    ;; remove leading (, ) or SPC from extracted entries string
    (replace-regexp-in-string "^[\(\) ]" "")))

(defun khoj--extract-entries-as-images (json-response query)
  "Convert JSON-RESPONSE, QUERY from API to html with images."
  (let ((image-results-buffer-html-format-str "<html>\n<body>\n<h1>%s</h1>%s\n\n</body>\n</html>")
        ;; Format string to wrap images into html img, href tags with metadata in headings
        (image-result-html-format-str "\n\n<h2>Score: %s Meta: %s Image: %s</h2>\n\n<a href=\"%s\">\n<img src=\"%s?%s\" width=%s height=%s>\n</a>"))
    (thread-last
      json-response
      ;; Extract each image entry from response and render as html
      (mapcar (lambda (json-response-item)
                (let ((score (cdr (assoc 'score json-response-item)))
                      (metadata_score (cdr (assoc 'metadata_score (assoc 'additional json-response-item))))
                      (image_score (cdr (assoc 'image_score (assoc 'additional json-response-item))))
                      (image_url (concat khoj-server-url (cdr (assoc 'entry json-response-item)))))
                  ;; Wrap images into html img, href tags with metadata in headings
                  (format image-result-html-format-str
                          ;; image scores metadata
                          score metadata_score image_score
                          ;; image url
                          image_url image_url (random 10000)
                          ;; image dimensions
                          khoj-image-width khoj-image-height))))
      ;; Collate entries into single html page string
      (format image-results-buffer-html-format-str query)
      ;; remove leading (, ) or SPC from extracted entries string
      (replace-regexp-in-string "^[\(\) ]" "")
      ;; remove trailing (, ) or SPC from extracted entries string
      (replace-regexp-in-string "[\(\) ]$" ""))))

(defun khoj--extract-entries (json-response query)
  "Convert JSON-RESPONSE, QUERY from API to text entries."
  (thread-last json-response
               ;; extract and render entries from API response
               (mapcar (lambda (json-response-item)
                         (thread-last
                           ;; Extract pdf entry from each item in json response
                           (cdr (assoc 'entry json-response-item))
                           (format "%s\n\n")
                           ;; Standardize results to 2nd level heading for consistent rendering
                           (replace-regexp-in-string "^\*+" "")
                           ;; Standardize results to 2nd level heading for consistent rendering
                           (replace-regexp-in-string "^\#+" "")
                           ;; Format entries as org entry string
                           (format "** %s"))))
               ;; Set query as heading in rendered results buffer
               (format "* %s\n%s\n" query)
               ;; remove leading (, ) or SPC from extracted entries string
               (replace-regexp-in-string "^[\(\) ]" "")
               ;; remove trailing (, ) or SPC from extracted entries string
               (replace-regexp-in-string "[\(\) ]$" "")))

(defun khoj--buffer-name-to-content-type (buffer-name)
  "Infer content type based on BUFFER-NAME."
  (let ((enabled-content-types (khoj--get-enabled-content-types))
        (file-extension (file-name-extension buffer-name)))
    (cond
     ((and (member 'org enabled-content-types) (equal file-extension "org")) "org")
     ((and (member 'pdf enabled-content-types) (equal file-extension "pdf")) "pdf")
     ((and (member 'markdown enabled-content-types) (or (equal file-extension "markdown") (equal file-extension "md"))) "markdown")
     (t khoj-default-content-type))))


;; --------------
;; Query Khoj API
;; --------------
(defun khoj--get-enabled-content-types ()
  "Get content types enabled for search from API."
  (let ((config-url (format "%s/api/config/types" khoj-server-url))
        (url-request-method "GET")
        (url-request-extra-headers `(("Authorization" . ,(format "Bearer %s" khoj-api-key)))))
    (with-temp-buffer
      (url-insert-file-contents config-url)
      (thread-last
        (json-parse-buffer :object-type 'alist)
        (mapcar #'intern)))))

(defun khoj--construct-search-api-query (query content-type &optional rerank)
  "Construct Search API Query.
Use QUERY, CONTENT-TYPE and (optional) RERANK as query params"
  (let ((rerank (or rerank "false"))
        (encoded-query (url-hexify-string query)))
    (format "%s/api/search?q=%s&t=%s&r=%s&n=%s&client=emacs" khoj-server-url encoded-query content-type rerank khoj-results-count)))

(defun khoj--query-search-api-and-render-results (query-url content-type query buffer-name)
  "Query Khoj Search with QUERY-URL.
Render results in BUFFER-NAME using QUERY, CONTENT-TYPE."
  ;; get json response from api
  (with-current-buffer buffer-name
    (let ((inhibit-read-only t)
          (url-request-method "GET")
          (url-request-extra-headers `(("Authorization" . ,(format "Bearer %s" khoj-api-key)))))
      (erase-buffer)
      (url-insert-file-contents query-url)))
  ;; render json response into formatted entries
  (with-current-buffer buffer-name
    (let ((inhibit-read-only t)
          (json-response (json-parse-buffer :object-type 'alist)))
      (erase-buffer)
      (insert
       (cond ((equal content-type "org") (khoj--extract-entries-as-org json-response query))
             ((equal content-type "markdown") (khoj--extract-entries-as-markdown json-response query))
             ((equal content-type "pdf") (khoj--extract-entries-as-pdf json-response query))
             ((equal content-type "image") (khoj--extract-entries-as-images json-response query))
             (t (khoj--extract-entries json-response query))))
      (cond ((or (equal content-type "all")
                 (equal content-type "pdf")
                 (equal content-type "org"))
             (progn (visual-line-mode)
                    (org-mode)
                   (setq-local
                    org-startup-folded "showall"
                    org-hide-leading-stars t
                    org-startup-with-inline-images t)
                   (org-set-startup-visibility)))
            ((equal content-type "markdown") (progn (markdown-mode)
                                                    (visual-line-mode)))
            ((equal content-type "image") (progn (shr-render-region (point-min) (point-max))
                                                (goto-char (point-min))))
            (t (fundamental-mode))))
    (read-only-mode t)))


;; ----------------
;; Khoj Chat
;; ----------------

(defun khoj--chat ()
  "Chat with Khoj."
  (interactive)
  (when (not (get-buffer khoj--chat-buffer-name))
      (khoj--load-chat-history khoj--chat-buffer-name))
  (switch-to-buffer khoj--chat-buffer-name)
  (let ((query (read-string "Query: ")))
    (when (not (string-empty-p query))
      (khoj--query-chat-api-and-render-messages query khoj--chat-buffer-name))))

(defun khoj--load-chat-history (buffer-name)
  "Load Khoj Chat conversation history into BUFFER-NAME."
  (let ((json-response (cdr (assoc 'response (khoj--get-chat-history-api)))))
    (with-current-buffer (get-buffer-create buffer-name)
      (erase-buffer)
      (insert "* Khoj Chat\n")
      (thread-last
        json-response
        ;; generate chat messages from Khoj Chat API response
        (mapcar #'khoj--render-chat-response)
        ;; insert chat messages into Khoj Chat Buffer
        (mapc #'insert))
      (progn
        (org-mode)
        (khoj--add-hover-text-to-footnote-refs (point-min))

        ;; render reference footnotes as superscript
        (setq-local
         org-startup-folded "showall"
         org-hide-leading-stars t
         org-use-sub-superscripts '{}
         org-pretty-entities-include-sub-superscripts t
         org-pretty-entities t)
        (org-set-startup-visibility)

        ;; create khoj chat shortcut keybindings
        (use-local-map (copy-keymap org-mode-map))
        (local-set-key (kbd "m") #'khoj--chat)
        (local-set-key (kbd "C-x m") #'khoj--chat)

        ;; enable minor modes for khoj chat
        (visual-line-mode)
        (read-only-mode t)))))

(defun khoj--add-hover-text-to-footnote-refs (start-pos)
  "Show footnote defs on mouse hover on footnote refs from START-POS."
  (org-with-wide-buffer
   (goto-char start-pos)
   (while (re-search-forward org-footnote-re nil t)
     (backward-char)
     (let* ((context (org-element-context))
            (label (org-element-property :label context))
            (footnote-def (nth 3 (org-footnote-get-definition label)))
            (footnote-width (if (< (length footnote-def) 70) nil 70))
            (begin-pos (org-element-property :begin context))
            (end-pos (org-element-property :end context))
            (overlay (make-overlay begin-pos end-pos)))
       (when (memq (org-element-type context)
                   '(footnote-reference))
         (-->
          footnote-def
          ;; truncate footnote definition if required
          (substring it 0 footnote-width)
          ;; append continuation suffix if truncated
          (concat it (if footnote-width "..." ""))
          ;; show definition on hover on footnote reference
          (overlay-put overlay 'help-echo it)))))))

(defun khoj--query-chat-api-and-render-messages (query buffer-name)
  "Send QUERY to Khoj Chat. Render the chat messages from exchange in BUFFER-NAME."
  ;; render json response into formatted chat messages
  (with-current-buffer (get-buffer buffer-name)
    (let ((inhibit-read-only t)
          (new-content-start-pos (point-max))
          (query-time (format-time-string "%F %T"))
          (json-response (khoj--query-chat-api query)))
      (goto-char new-content-start-pos)
      (insert
       (khoj--render-chat-message query "you" query-time)
       (khoj--render-chat-response json-response))
      (khoj--add-hover-text-to-footnote-refs new-content-start-pos))
    (progn
      (org-set-startup-visibility)
      (visual-line-mode)
      (re-search-backward "^\*+ 🏮" nil t))))

(defun khoj--query-chat-api (query)
  "Send QUERY to Khoj Chat API."
  (let* ((url-request-method "GET")
         (encoded-query (url-hexify-string query))
         (url-request-extra-headers `(("Authorization" . ,(format "Bearer %s" khoj-api-key))))
         (query-url (format "%s/api/chat?q=%s&n=%s&client=emacs" khoj-server-url encoded-query khoj-results-count)))
    (with-temp-buffer
      (condition-case ex
          (progn
            (url-insert-file-contents query-url)
            (json-parse-buffer :object-type 'alist))
        ('file-error (cond ((string-match "Internal server error" (nth 2 ex))
                      (message "Chat processor not configured. Configure OpenAI API key and restart it. Exception: [%s]" ex))
                     (t (message "Chat exception: [%s]" ex))))))))


(defun khoj--get-chat-history-api ()
  "Send QUERY to Khoj Chat History API."
  (let* ((url-request-method "GET")
         (url-request-extra-headers `(("Authorization" . ,(format "Bearer %s" khoj-api-key))))
         (query-url (format "%s/api/chat/history?client=emacs" khoj-server-url)))
    (with-temp-buffer
      (condition-case ex
          (progn
            (url-insert-file-contents query-url)
            (json-parse-buffer :object-type 'alist))
        ('file-error (cond ((string-match "Internal server error" (nth 2 ex))
                      (message "Chat processor not configured. Configure OpenAI API key and restart it. Exception: [%s]" ex))
                     (t (message "Chat exception: [%s]" ex))))))))


(defun khoj--render-chat-message (message sender &optional receive-date)
  "Render chat messages as `org-mode' list item.
MESSAGE is the text of the chat message.
SENDER is the message sender.
RECEIVE-DATE is the message receive date."
  (let ((first-message-line (car (split-string message "\n" t)))
        (rest-message-lines (string-join (cdr (split-string message "\n" t)) "\n"))
        (heading-level (if (equal sender "you") "**" "***"))
        (emojified-sender (if (equal sender "you") "🤔 *You*" "🏮 *Khoj*"))
        (suffix-newlines (if (equal sender "khoj") "\n\n" ""))
        (received (or receive-date (format-time-string "%F %T"))))
    (format "%s %s: %s\n   :PROPERTIES:\n   :RECEIVED: [%s]\n   :END:\n%s\n%s"
            heading-level
            emojified-sender
            first-message-line
            received
            rest-message-lines
            suffix-newlines)))

(defun khoj--generate-reference (reference)
  "Create `org-mode' footnotes with REFERENCE."
  (setq khoj--reference-count (1+ khoj--reference-count))
  (cons
   (propertize (format "^{ [fn:%x]}" khoj--reference-count) 'help-echo reference)
   (thread-last
     reference
     ;; remove filename top heading line from reference
     ;; prevents actual reference heading in next line jumping out of references footnote section
     (replace-regexp-in-string "^\* .*\n" "")
     ;; remove multiple, consecutive empty lines from reference
     (replace-regexp-in-string "\n\n" "\n")
     (format "\n[fn:%x] %s" khoj--reference-count))))

(defun khoj--render-chat-response (json-response)
  "Render chat message using JSON-RESPONSE from Khoj Chat API."
  (let* ((message (cdr (or (assoc 'response json-response) (assoc 'message json-response))))
         (sender (cdr (assoc 'by json-response)))
         (receive-date (cdr (assoc 'created json-response)))
         (references (or (cdr (assoc 'context json-response)) '()))
         (footnotes (mapcar #'khoj--generate-reference references))
         (footnote-links (mapcar #'car footnotes))
         (footnote-defs (mapcar #'cdr footnotes)))
    (thread-first
      ;; concatenate khoj message and references from API
      (concat
       message
       ;; append reference links to khoj message
       (string-join footnote-links "")
       ;; append reference sub-section to khoj message and fold it
       (if footnote-defs "\n**** References\n:PROPERTIES:\n:VISIBILITY: folded\n:END:" "")
       ;; append reference definitions to references subsection
       (string-join footnote-defs " "))
      ;; Render chat message using data obtained from API
      (khoj--render-chat-message sender receive-date))))


;; ------------------
;; Incremental Search
;; ------------------

(defun khoj--incremental-search (&optional rerank)
  "Perform Incremental Search on Khoj. Allow optional RERANK of results."
  (let* ((rerank-str (cond (rerank "true") (t "false")))
         (khoj-buffer-name (get-buffer-create khoj--search-buffer-name))
         (query (minibuffer-contents-no-properties))
         (query-url (khoj--construct-search-api-query query khoj--content-type rerank-str)))
    ;; Query khoj API only when user in khoj minibuffer and non-empty query
    ;; Prevents querying if
    ;;   1. user hasn't started typing query
    ;;   2. during recursive edits
    ;;   3. with contents of other buffers user may jump to
    ;;   4. search not triggered right after rerank
    ;;      ignore to not overwrite reranked results before the user even sees them
    (if khoj--rerank
        (setq khoj--rerank nil)
      (when
          (and
           (not (equal query ""))
           (active-minibuffer-window)
           (equal (current-buffer) khoj--minibuffer-window))
      (progn
        (when rerank
          (setq khoj--rerank t)
          (message "khoj.el: Rerank Results"))
        (khoj--query-search-api-and-render-results
         query-url
         khoj--content-type
         query
         khoj-buffer-name))))))

(defun khoj--delete-open-network-connections-to-server ()
  "Delete all network connections to khoj server."
  (dolist (proc (process-list))
    (let ((proc-buf (buffer-name (process-buffer proc)))
          (khoj-network-proc-buf (string-join (split-string khoj-server-url "://") " ")))
      (when (string-match (format "%s" khoj-network-proc-buf) proc-buf)
        (ignore-errors (delete-process proc))))))

(defun khoj--teardown-incremental-search ()
  "Teardown hooks used for incremental search."
  (message "khoj.el: Teardown Incremental Search")
  ;; unset khoj minibuffer window
  (setq khoj--minibuffer-window nil)
  (when (and khoj--search-on-idle-timer
             (timerp khoj--search-on-idle-timer))
    (cancel-timer khoj--search-on-idle-timer))
  ;; delete open connections to khoj server
  (khoj--delete-open-network-connections-to-server)
  ;; remove hooks for khoj incremental query and self
  (remove-hook 'post-command-hook #'khoj--incremental-search)
  (remove-hook 'minibuffer-exit-hook #'khoj--teardown-incremental-search))

(defun khoj-incremental ()
  "Natural, Incremental Search for your personal notes and documents."
  (interactive)
  (let* ((khoj-buffer-name (get-buffer-create khoj--search-buffer-name)))
    ;; switch to khoj results buffer
    (switch-to-buffer khoj-buffer-name)
    ;; open and setup minibuffer for incremental search
    (minibuffer-with-setup-hook
        (lambda ()
          ;; Add khoj keybindings for configuring search to minibuffer keybindings
          (khoj--make-search-keymap minibuffer-local-map)
          ;; Display information on keybindings to customize khoj search
          (khoj--display-keybinding-info)
          ;; set current (mini-)buffer entered as khoj minibuffer
          ;; used to query khoj API only when user in khoj minibuffer
          (setq khoj--minibuffer-window (current-buffer))
          ; do khoj incremental search after idle time
          (setq khoj--search-on-idle-timer (run-with-idle-timer khoj-search-on-idle-time t #'khoj--incremental-search))
          ; teardown khoj incremental search on minibuffer exit
          (add-hook 'minibuffer-exit-hook #'khoj--teardown-incremental-search))
      (read-string khoj--query-prompt))))


;; --------------
;; Similar Search
;; --------------

(defun khoj--get-current-outline-entry-text ()
  "Get text under current outline section."
  (string-trim
   ;; get text of current outline entry
   (cond
    ;; when at heading of entry
    ((looking-at outline-regexp)
     (buffer-substring-no-properties
      (point)
      (save-excursion (outline-next-heading) (point))))
    ;; when within entry
    (t (buffer-substring-no-properties
        (save-excursion (outline-previous-heading) (point))
        (save-excursion (outline-next-heading) (point)))))))

(defun khoj--get-current-paragraph-text ()
  "Get trimmed text in current paragraph at point.
Paragraph only starts at first text after blank line."
  (string-trim
   (cond
    ;; when at end of a middle paragraph
    ((and (looking-at paragraph-start) (not (equal (point) (point-min))))
     (buffer-substring-no-properties
      (save-excursion (backward-paragraph) (point))
      (point)))
    ;; else
    (t (thing-at-point 'paragraph t)))))


(defun khoj--find-similar (&optional content-type)
  "Find items of CONTENT-TYPE in khoj index similar to text surrounding point."
  (interactive)
  (let* ((rerank "true")
         ;; set content type to: specified > based on current buffer > default type
         (content-type (or content-type (khoj--buffer-name-to-content-type (buffer-name))))
         ;; get text surrounding current point based on the major mode context
         (query (cond
                 ;; get section outline derived mode like org or markdown
                 ((or (derived-mode-p 'outline-mode) (equal major-mode 'markdown-mode))
                  (khoj--get-current-outline-entry-text))
                 ;; get paragraph, if in text mode
                 (t
                  (khoj--get-current-paragraph-text))))
         (query-url (khoj--construct-search-api-query query content-type rerank))
         ;; extract heading to show in result buffer from query
         (query-title
          (format "Similar to: %s"
                  (replace-regexp-in-string "^[#\\*]* " "" (car (split-string query "\n")))))
         (buffer-name (get-buffer-create khoj--search-buffer-name)))
    (progn
      (khoj--query-search-api-and-render-results
       query-url
       content-type
       query-title
       buffer-name)
      (switch-to-buffer buffer-name)
      (goto-char (point-min)))))


;; ---------
;; Khoj Menu
;; ---------

(defun khoj--setup-and-show-menu ()
  "Create Transient menu for khoj and show it."
  ;; Create the Khoj Transient menu
  (transient-define-argument khoj--content-type-switch ()
    :class 'transient-switches
    :argument-format "--content-type=%s"
    :argument-regexp ".+"
    ;; set content type to: last used > based on current buffer > default type
    :init-value (lambda (obj) (oset obj value (format "--content-type=%s" (or khoj--content-type (khoj--buffer-name-to-content-type (buffer-name))))))
    ;; dynamically set choices to content types enabled on khoj backend
    :choices (or (ignore-errors (mapcar #'symbol-name (khoj--get-enabled-content-types))) '("all" "org" "markdown" "pdf" "image")))

  (transient-define-suffix khoj--search-command (&optional args)
    (interactive (list (transient-args transient-current-command)))
    (progn
      ;; set content type to: specified > last used > based on current buffer > default type
      (setq khoj--content-type (or (transient-arg-value "--content-type=" args) (khoj--buffer-name-to-content-type (buffer-name))))
      ;; set results count to: specified > last used > to default
      (setq khoj-results-count (or (transient-arg-value "--results-count=" args) khoj-results-count))
      ;; trigger incremental search
      (call-interactively #'khoj-incremental)))

  (transient-define-suffix khoj--find-similar-command (&optional args)
    "Find items similar to current item at point."
    (interactive (list (transient-args transient-current-command)))
    (progn
      ;; set content type to: specified > last used > based on current buffer > default type
      (setq khoj--content-type (or (transient-arg-value "--content-type=" args) (khoj--buffer-name-to-content-type (buffer-name))))
      ;; set results count to: specified > last used > to default
      (setq khoj-results-count (or (transient-arg-value "--results-count=" args) khoj-results-count))
      (khoj--find-similar khoj--content-type)))

  (transient-define-suffix khoj--update-command (&optional args)
    "Call khoj API to update index of specified content type."
    (interactive (list (transient-args transient-current-command)))
    (let* ((force-update (if (member "--force-update" args) "true" "false"))
           ;; set content type to: specified > last used > based on current buffer > default type
           (content-type (or (transient-arg-value "--content-type=" args) (khoj--buffer-name-to-content-type (buffer-name))))
           (url-request-method "GET"))
      (progn
        (setq khoj--content-type content-type)
        (khoj--server-index-files force-update content-type))))

  (transient-define-suffix khoj--chat-command (&optional _)
    "Command to Chat with Khoj."
    (interactive (list (transient-args transient-current-command)))
    (khoj--chat))

  (transient-define-prefix khoj--menu ()
    "Create Khoj Menu to Configure and Execute Commands."
    [["Configure Search"
      ("n" "Results Count" "--results-count=" :init-value (lambda (obj) (oset obj value (format "%s" khoj-results-count))))
      ("t" "Content Type" khoj--content-type-switch)]
     ["Configure Update"
      ("-f" "Force Update" "--force-update")]]
    [["Act"
      ("c" "Chat" khoj--chat-command)
      ("s" "Search" khoj--search-command)
      ("f" "Find Similar" khoj--find-similar-command)
      ("u" "Update" khoj--update-command)
      ("q" "Quit" transient-quit-one)]])

  ;; Show the Khoj Transient menu
  (khoj--menu))


;; ----------
;; Entrypoint
;; ----------

;;;###autoload
(defun khoj ()
  "Provide natural, search assistance for your notes, documents and images."
  (interactive)
  (when khoj-auto-setup
    (khoj-setup t))
  (khoj--setup-and-show-menu))

(provide 'khoj)

;;; khoj.el ends here