;;; elfeed.el --- An Emacs Atom/RSS feed reader -*- lexical-binding: t; -*-

;; This is free and unencumbered software released into the public domain.

;; Author: Christopher Wellons <wellons@nullprogram.com>
;; Maintainer: Karthik Chikmagalur <karthik.chikmagalur@gmail.com>, Ihor Radchenko <yantar92@posteo.net>, Daniel Mendler <mail@daniel-mendler.de>
;; URL: https://github.com/emacs-elfeed/elfeed
;; Version: 3.4.2
;; Package-Requires: ((emacs "28.1") (compat "31"))
;; Keywords: network, comm, hypermedia

;;; Commentary:

;; Elfeed is a web feed client for Emacs, which supports Atom and RSS
;; feeds.
;;
;; After installation of Elfeed from a package archive, invoke M-x
;; elfeed to open the Elfeed search buffer.  The list of feeds can be
;; configured in your user configuration.
;;
;;     (setq elfeed-feeds
;;       '(("http://nullprogram.com/feed/" blog emacs)
;;         "http://www.50ply.com/atom.xml" ;; no autotagging
;;         ("http://nedroid.com/feed/" webcomic)))
;;
;; For the start a few basic commands suffice.  Inside the search
;; buffer press G to refresh the feeds, s to live filter the entries,
;; or c to reset the search filter.  Press RET on an entry to show it
;; in a separate buffer.
;;
;; See the README for the full documentation.

;;; Code:

(eval-when-compile (require 'subr-x))
(require 'xml-query)
(require 'url-queue)

(require 'elfeed-db)
(require 'elfeed-lib)
(require 'elfeed-log)
(require 'elfeed-curl)

(defgroup elfeed ()
  "An Emacs web feed reader."
  :group 'web
  :group 'comm)

(defconst elfeed-version "3.4.2")

(defcustom elfeed-feeds ()
  "List of all feeds that Elfeed should follow.
You must add your feeds to this list.

In its simplest form this will be a list of strings of feed URLs.
Items in this list can also be list whose car is the feed URL
and cdr is a list of symbols to be applied to all discovered
entries as tags (\"autotags\").  For example,

  (setq elfeed-feeds \\='(\"http://foo/\"
                       \"http://bar/\"
                       (\"http://baz/\" comic)))

All entries from the \"baz\" feed will be tagged as \"comic\"
when they are first discovered."
  :group 'elfeed
  :type '(repeat (choice string
                         (cons string (repeat symbol)))))

(defcustom elfeed-feed-functions
  (list #'elfeed-get-link-at-point
        #'thing-at-point-url-at-point
        #'elfeed-clipboard-get)
  "List of functions to use to get possible feeds for `elfeed-add-feed'.
Each function should accept no arguments, and return a string or nil."
  :group 'elfeed
  :type 'hook
  :options (list #'elfeed-get-link-at-point
                 #'thing-at-point-url-at-point
                 #'elfeed-clipboard-get))

(defcustom elfeed-use-curl
  (not (null (executable-find elfeed-curl-program-name)))
  "If non-nil, fetch feeds using curl instead of `url-retrieve'."
  :group 'elfeed
  :type 'boolean)

(defcustom elfeed-use-libxml nil
  "Use faster libxml2 for parsing.
This setting is experimental, and disabled for now.  It may lead to
subtle differences to the usual xml.el parser, which renders certain
feeds unreadable.  Enabling may yield a performance boost."
  :group 'elfeed
  :type 'boolean)

(defcustom elfeed-user-agent (format "Emacs Elfeed %s" elfeed-version)
  "User agent string to use for Elfeed (requires `elfeed-use-curl')."
  :group 'elfeed
  :type 'string)

(defcustom elfeed-initial-tags '(unread)
  "Initial tags for new entries."
  :group 'elfeed
  :type '(repeat symbol))

(defcustom elfeed-confirm-browse-url 2
  "Confirm `browse-url' when opening this many or more URLs."
  :group 'elfeed
  :type '(choice (const :tag "No confirmation" nil)
                 (const :tag "Always confirm" t)
                 natnum))

(defun elfeed--confirm-browse-url-p (&optional count)
  "Confirm browsing COUNT URLs, with COUNT defaulting to 1."
  (let ((confirm elfeed-confirm-browse-url)
        (count (or count 1)))
    (or (not confirm)
        (and (numberp confirm) (< count confirm))
        (y-or-n-p (if (= count 1)
                      "Browse URL? "
                    (format "Browse %d URLs? " count))))))

(defcustom elfeed-default-directory nil
  "Default directory for all Elfeed buffers."
  :group 'elfeed
  :type '(choice (const :tag "current" nil)
                 (const :tag "user home" "~/")
                 directory))

(defun elfeed-default-directory ()
  "Return default directory to be used by Elfeed buffers."
  (if (and elfeed-default-directory
           (file-exists-p elfeed-default-directory))
      (file-name-as-directory (expand-file-name elfeed-default-directory))
    default-directory))

;; Fetching:

(defvar elfeed-http-error-hooks ()
  "Hooks to run when an http connection error occurs.
It is called with 2 arguments.  The first argument is the url of
the failing feed.  The second argument is the http status code.")

(defvar elfeed-parse-error-hooks ()
  "Hooks to run when an error occurs during the parsing of a feed.
It is called with 2 arguments.  The first argument is the url of
the failing feed.  The second argument is the error message .")

(defvar elfeed-update-hooks ()
  "Hooks to run any time a feed update has completed a request.
It is called with 1 argument: the URL of the feed that was just
updated.  The hook is called even when no new entries were
found.")

(defvar elfeed-update-init-hooks ()
  "Hooks called when one or more feed updates have begun.
Receivers may want to, say, update a display to indicate that
updates are pending.")

(defvar elfeed-tag-hooks ()
  "Hooks called when one or more entries add tags.
It is called with 2 arguments.  The first argument is the entry
list.  The second argument is the tag list.")

(defvar elfeed-untag-hooks ()
  "Hooks called when one or more entries remove tags.
It is called with 2 arguments.  The first argument is the entry
list.  The second argument is the tag list.")

(defvar elfeed--inhibit-update-init-hooks nil
  "When non-nil, don't run `elfeed-update-init-hooks'.")

(defun elfeed-queue-count-active ()
  "Return the number of items in process."
  (if elfeed-use-curl
      elfeed-curl-queue-active
    (cl-count-if #'url-queue-buffer url-queue)))

(defun elfeed-queue-count-total ()
  "Return the number of items in process."
  (if elfeed-use-curl
      (+ (length elfeed-curl-queue) elfeed-curl-queue-active)
    (length url-queue)))

(defun elfeed-set-max-connections (n)
  "Limit the maximum number of concurrent connections to N."
  (if elfeed-use-curl
      (setf elfeed-curl-max-connections n)
    (setf url-queue-parallel-processes n)))

(defun elfeed-get-max-connections ()
  "Get the maximum number of concurrent connections."
  (if elfeed-use-curl
      elfeed-curl-max-connections
    url-queue-parallel-processes))

(defun elfeed-set-timeout (seconds)
  "Limit the time for fetching a feed to SECONDS."
  (if elfeed-use-curl
      (setf elfeed-curl-timeout seconds)
    (setf url-queue-timeout seconds)))

(defun elfeed-get-timeout ()
  "Get the time limit for fetching feeds in SECONDS."
  (if elfeed-use-curl
      elfeed-curl-timeout
    url-queue-timeout))

(defun elfeed-is-status-error (status use-curl)
  "Check if HTTP request returned STATUS means a error.
USE-CURL is needed since the interpretation depends on if curl is used."
  (or (and use-curl (null status)) ; nil = error
      (and (not use-curl) (eq (car status) :error))))

(defmacro elfeed-with-fetch (url &rest body)
  "Asynchronously run BODY in a buffer with the contents from URL.
This macro is anaphoric, with STATUS referring to the status from
`url-retrieve'/cURL and USE-CURL being the original invoked-value
of `elfeed-use-curl'."
  (declare (indent defun))
  `(let* ((use-curl elfeed-use-curl) ; capture current value in closure
          (cb (lambda (status) ,@body)))
     (if elfeed-use-curl
         (let* ((feed (elfeed-db-get-feed url))
                (last-modified (elfeed-meta feed :last-modified))
                (etag (elfeed-meta feed :etag))
                (headers `(("User-Agent" . ,elfeed-user-agent))))
           (when etag
             (push `("If-None-Match" . ,etag) headers))
           (when last-modified
             (push `("If-Modified-Since" . ,last-modified) headers))
           (elfeed-curl-enqueue ,url cb :headers headers))
       (url-queue-retrieve ,url cb () t t))))

(defun elfeed-unjam ()
  "Manually clear the connection pool when connections fail to timeout.
This is a workaround for issues in `url-queue-retrieve'."
  (interactive)
  (if elfeed-use-curl
      (setf elfeed-curl-queue nil
            elfeed-curl-queue-active 0)
    (when-let* ((fails (mapcar #'url-queue-url url-queue)))
      (elfeed-log 'warn "Elfeed aborted feeds: %s"
                  (mapconcat #'identity fails " ")))
    (setf url-queue nil))
  (run-hooks 'elfeed-update-init-hooks))

;; Parsing:

(defun elfeed-feed-type (content)
  "Obtain the feed type (:atom, :rss, :rss1.0) or nil for unknown from CONTENT."
  (let ((top (xml-query-strip-ns (caar content))))
    (cadr (assoc top '((feed :atom)
                       (rss :rss)
                       (RDF :rss1.0))))))

(defun elfeed-generate-id (&optional content)
  "Generate an ID based on CONTENT or from the current time."
  (concat "urn:sha1:" (sha1 (format "%s" (or content (float-time))))))

(defun elfeed--atom-content (entry)
  "Get content string from ENTRY."
  (let ((content-type (xml-query* (content :type) entry)))
    (if (equal content-type "xhtml")
        (with-temp-buffer
          (let ((xhtml (cddr (xml-query* (content) entry))))
            (dolist (element xhtml)
              (if (stringp element)
                  (insert element)
                (elfeed-xml-unparse element))))
          (buffer-string))
      (when-let* ((all-content
                   (or (xml-query-all* (content *) entry)
                       (xml-query-all* (summary *) entry))))
        (apply #'concat all-content)))))

(defvar elfeed-new-entry-parse-hook '()
  "Hook to be called after parsing a new entry.

Take three arguments: the feed TYPE, the XML structure for the
entry, and the Elfeed ENTRY object.  Return value is ignored, and
is called for side-effects on the ENTRY object.")

(defsubst elfeed--fixup-protocol (protocol url)
  "Prepend PROTOCOL to URL if it is protocol-relative.
If PROTOCOL is nil, returns URL."
  (if (and protocol url (string-match-p "\\`//[^/]" url))
      (concat protocol ":" url)
    url))

(defsubst elfeed--atom-authors-to-plist (authors)
  "Parse list of AUTHORS as XML tags into list of plists."
  (let ((result ()))
    (dolist (author authors)
      (let ((plist ())
            (name (xml-query* (name *) author))
            (uri (xml-query* (uri *) author))
            (email (xml-query* (email *) author)))
        (when email
          (setf plist (list :email (elfeed-cleanup email))))
        (when uri
          (setf plist (nconc (list :uri (elfeed-cleanup uri)) plist)))
        (when name
          (setf plist (nconc (list :name (elfeed-cleanup name)) plist)))
        (push plist result)))
    (nreverse result)))

(defsubst elfeed--creators-to-plist (creators)
  "Convert Dublin Core list of CREATORS into an authors plist."
  (cl-loop for creator in creators
           collect (list :name creator)))

(defun elfeed-entries-from-atom (url xml)
  "Turn parsed Atom content into a list of elfeed-entry structs.
URL identifies the feed and XML is the parsed content."
  (let* ((feed-id url)
         (protocol (url-type (url-generic-parse-url url)))
         (namespace (elfeed-url-to-namespace url))
         (feed (elfeed-db-get-feed feed-id))
         (title (elfeed-cleanup (xml-query* (feed title *) xml)))
         (authors (xml-query-all* (feed author) xml))
         (xml-base (or (xml-query* (feed :base) xml) url))
         (autotags (elfeed-feed-autotags url)))
    (setf (elfeed-feed-url feed) url
          (elfeed-feed-title feed) title
          (elfeed-feed-author feed) (elfeed--atom-authors-to-plist authors))
    (cl-loop for entry in (xml-query-all* (feed entry) xml) collect
             (let* ((title (or (xml-query* (title *) entry) ""))
                    (xml-base (elfeed-update-location
                               xml-base (xml-query* (:base) (list entry))))
                    (anylink (xml-query* (link :href) entry))
                    (altlink (xml-query* (link [rel "alternate"] :href) entry))
                    (link (elfeed--fixup-protocol
                           protocol
                           (elfeed-update-location xml-base
                                                   (or altlink anylink))))
                    (date (or (xml-query* (published *) entry)
                              (xml-query* (updated *) entry)
                              (xml-query* (date *) entry)
                              (xml-query* (modified *) entry) ; Atom 0.3
                              (xml-query* (issued *) entry))) ; Atom 0.3
                    (authors (nconc (elfeed--atom-authors-to-plist
                                     (xml-query-all* (author) entry))
                                    ;; Dublin Core
                                    (elfeed--creators-to-plist
                                     (xml-query-all* (creator *) entry))))
                    (categories (xml-query-all* (category :term) entry))
                    (content (elfeed--atom-content entry))
                    (id (or (xml-query* (id *) entry) link
                            (elfeed-generate-id content)))
                    (type (or (xml-query* (content :type) entry)
                              (xml-query* (summary :type) entry)
                              ""))
                    (tags (elfeed-normalize-tags autotags elfeed-initial-tags))
                    (content-type (if (string-match-p "html" type) 'html nil))
                    (etags (xml-query-all* (link [rel "enclosure"]) entry))
                    (enclosures
                     (cl-loop for enclosure in etags
                              for wrap = (list enclosure)
                              for href = (xml-query* (:href) wrap)
                              for type = (xml-query* (:type) wrap)
                              for length = (xml-query* (:length) wrap)
                              collect (list href type length)))
                    (db-entry (elfeed-entry--create
                               :title (elfeed-cleanup title)
                               :feed-id feed-id
                               :id (cons namespace (elfeed-cleanup id))
                               :link (elfeed-cleanup link)
                               :tags tags
                               :date (or (elfeed-float-time date) (float-time))
                               :content content
                               :enclosures enclosures
                               :content-type content-type
                               :meta `(,@(when authors
                                           (list :authors authors))
                                       ,@(when categories
                                           (list :categories categories))))))
               (run-hook-with-args 'elfeed-new-entry-parse-hook
                                   :atom entry db-entry)
               db-entry))))

(defsubst elfeed--rss-author-to-plist (author)
  "Parse an RSS AUTHOR element into an authors plist."
  (when author
    (let ((clean (elfeed-cleanup author)))
      (if (string-match "\\`\\(.*\\) (\\([^)]+\\))\\'" clean)
          (list (list :name (match-string 2 clean)
                      :email (match-string 1 clean)))
        (list (list :email clean))))))

(defun elfeed-entries-from-rss (url xml)
  "Turn parsed RSS content into a list of elfeed-entry structs.
URL identifies the feed and XML is the parsed content."
  (let* ((feed-id url)
         (protocol (url-type (url-generic-parse-url url)))
         (namespace (elfeed-url-to-namespace url))
         (feed (elfeed-db-get-feed feed-id))
         (title (elfeed-cleanup (xml-query* (rss channel title *) xml)))
         (autotags (elfeed-feed-autotags url)))
    (setf (elfeed-feed-url feed) url
          (elfeed-feed-title feed) title)
    (cl-loop for item in (xml-query-all* (rss channel item) xml) collect
             (let* ((title (or (xml-query* (title *) item) ""))
                    (guid (xml-query* (guid *) item))
                    (link (elfeed--fixup-protocol
                           protocol
                           (or (xml-query* (link *) item) guid)))
                    (date (or (xml-query* (pubDate *) item)
                              (xml-query* (date *) item)))
                    (authors (nconc (elfeed--rss-author-to-plist
                                     (xml-query* (author *) item))
                                    ;; Dublin Core
                                    (elfeed--creators-to-plist
                                     (xml-query-all* (creator *) item))))
                    (categories (xml-query-all* (category *) item))
                    (content (or (xml-query-all* (encoded *) item)
                                 (xml-query-all* (description *) item)))
                    (description (apply #'concat content))
                    (id (or guid link (elfeed-generate-id description)))
                    (full-id (cons namespace (elfeed-cleanup id)))
                    (original (elfeed-db-get-entry full-id))
                    (original-date (and original (elfeed-entry-date original)))
                    (tags (elfeed-normalize-tags autotags elfeed-initial-tags))
                    (etags (xml-query-all* (enclosure) item))
                    (enclosures
                     (cl-loop for enclosure in etags
                              for wrap = (list enclosure)
                              for url = (xml-query* (:url) wrap)
                              for type = (xml-query* (:type) wrap)
                              for length = (xml-query* (:length) wrap)
                              collect (list url type length)))
                    (db-entry (elfeed-entry--create
                               :title (elfeed-cleanup title)
                               :id full-id
                               :feed-id feed-id
                               :link (elfeed-cleanup link)
                               :tags tags
                               :date (elfeed-new-date-for-entry
                                      original-date date)
                               :enclosures enclosures
                               :content description
                               :content-type 'html
                               :meta `(,@(when authors
                                           (list :authors authors))
                                       ,@(when categories
                                           (list :categories categories))))))
               (run-hook-with-args 'elfeed-new-entry-parse-hook
                                   :rss item db-entry)
               db-entry))))

(defun elfeed-entries-from-rss1.0 (url xml)
  "Turn parsed RSS 1.0 content into a list of elfeed-entry structs.
URL identifies the feed and XML is the parsed content."
  (let* ((feed-id url)
         (namespace (elfeed-url-to-namespace url))
         (feed (elfeed-db-get-feed feed-id))
         (title (elfeed-cleanup (xml-query* (RDF channel title *) xml)))
         (autotags (elfeed-feed-autotags url)))
    (setf (elfeed-feed-url feed) url
          (elfeed-feed-title feed) title)
    (cl-loop for item in (xml-query-all* (RDF item) xml) collect
             (let* ((title (or (xml-query* (title *) item) ""))
                    (link (xml-query* (link *) item))
                    (date (or (xml-query* (pubDate *) item)
                              (xml-query* (date *) item)))
                    (description
                     (apply #'concat (xml-query-all* (description *) item)))
                    (id (or link (elfeed-generate-id description)))
                    (full-id (cons namespace (elfeed-cleanup id)))
                    (original (elfeed-db-get-entry full-id))
                    (original-date (and original (elfeed-entry-date original)))
                    (tags (elfeed-normalize-tags autotags elfeed-initial-tags))
                    (db-entry (elfeed-entry--create
                               :title (elfeed-cleanup title)
                               :id full-id
                               :feed-id feed-id
                               :link (elfeed-cleanup link)
                               :tags tags
                               :date (elfeed-new-date-for-entry
                                      original-date date)
                               :content description
                               :content-type 'html)))
               (run-hook-with-args 'elfeed-new-entry-parse-hook
                                   :rss1.0 item db-entry)
               db-entry))))

(defun elfeed-feed-list ()
  "Return a flat list version of `elfeed-feeds'.
Only a list of strings will be returned."
  ;; Validate elfeed-feeds and fail early rather than asynchronously later.
  (dolist (feed elfeed-feeds)
    (unless (cl-typecase feed
              (list (and (stringp (car feed))
                         (cl-every #'symbolp (cdr feed))))
              (string t))
      (error "elfeed-feeds malformed, bad entry: %S" feed)))
  (cl-loop for feed in elfeed-feeds
           when (listp feed) collect (car feed)
           else collect feed))

(defun elfeed-feed-autotags (url-or-feed)
  "Return tags to automatically apply to all entries from URL-OR-FEED."
  (let ((url (if (elfeed-feed-p url-or-feed)
                 (or (elfeed-feed-url url-or-feed)
                     (elfeed-feed-id url-or-feed))
               url-or-feed)))
    (mapcar #'elfeed-keyword->symbol (cdr (assoc url elfeed-feeds)))))

(defun elfeed-apply-autotags-now ()
  "Apply autotags to existing entries according to `elfeed-feeds'."
  (interactive)
  (with-elfeed-db-visit (entry feed)
    (apply #'elfeed-tag entry (elfeed-feed-autotags feed))))

(defun elfeed-handle-http-error (url status)
  "Handle an http error during retrieval of URL with STATUS code."
  (incf (elfeed-meta (elfeed-db-get-feed url) :failures 0))
  (run-hook-with-args 'elfeed-http-error-hooks url status)
  (elfeed-log 'error "%s: %S" url status))

(defun elfeed-handle-parse-error (url error)
  "Handle parse error during parsing of URL with ERROR message."
  (incf (elfeed-meta (elfeed-db-get-feed url) :failures 0))
  (run-hook-with-args 'elfeed-parse-error-hooks url error)
  (elfeed-log 'error "%s: %s" url error))

(defun elfeed-update-feed (url)
  "Update a specific feed identified by URL."
  (interactive (list (completing-read
                      "Feed: "
                      (completion-table-with-metadata
                       (elfeed-feed-list)
                       '((category . url))))))
  (unless elfeed--inhibit-update-init-hooks
    (run-hooks 'elfeed-update-init-hooks))
  (elfeed-with-fetch url
    (if (elfeed-is-status-error status use-curl)
        (let ((print-escape-newlines t))
          (elfeed-handle-http-error
           url (if use-curl elfeed-curl-error-message status)))
      (condition-case error
          (let ((feed (elfeed-db-get-feed url)))
            (unless use-curl
              (elfeed-move-to-first-empty-line)
              (set-buffer-multibyte t))
            (unless (eql elfeed-curl-status-code 304)
              ;; Update Last-Modified and Etag
              (setf (elfeed-meta feed :last-modified)
                    (cdr (assoc "last-modified" elfeed-curl-headers))
                    (elfeed-meta feed :etag)
                    (cdr (assoc "etag" elfeed-curl-headers)))
              (if (equal url elfeed-curl-location)
                  (setf (elfeed-meta feed :canonical-url) nil)
                (setf (elfeed-meta feed :canonical-url) elfeed-curl-location))
              (let* ((xml (elfeed-xml-parse-region (point) (point-max)))
                     (entries (cl-case (elfeed-feed-type xml)
                                (:atom (elfeed-entries-from-atom url xml))
                                (:rss (elfeed-entries-from-rss url xml))
                                (:rss1.0 (elfeed-entries-from-rss1.0 url xml))
                                (otherwise
                                 (error (elfeed-handle-parse-error
                                         url "Unknown feed type."))))))
                (elfeed-db-add entries))))
        (error (elfeed-handle-parse-error url error))))
    (unless use-curl
      (kill-buffer))
    (run-hook-with-args 'elfeed-update-hooks url)))

(defun elfeed-candidate-feeds ()
  "Return a list of possible feeds from `elfeed-feed-functions'."
  (let (res)
    (run-hook-wrapped
     'elfeed-feed-functions
     (lambda (fun)
       (let* ((val (elfeed-cleanup (funcall fun))))
         (when (and (not (zerop (length val)))
                    (elfeed-looks-like-url-p val))
           (cl-pushnew val res :test #'equal)))
       nil))
    (nreverse res)))

(cl-defun elfeed-add-feed (url &key save)
  "Manually add a feed at URL to the database.
If SAVE is non-nil the new value of ‘elfeed-feeds’ is saved.  When
called interactively, SAVE is set to t."
  (interactive
   (list
    (let* ((feeds (elfeed-candidate-feeds))
           (prompt (if feeds (concat "URL (default " (car feeds)  "): ")
                     "URL: "))
           (input (read-from-minibuffer prompt nil nil nil nil feeds))
           (result (elfeed-cleanup input)))
      (cond ((not (zerop (length result))) result)
            (feeds (car feeds))
            ((user-error "No feed to add"))))
    :save t))
  (cl-pushnew url elfeed-feeds :test #'equal)
  (when save
    (customize-save-variable 'elfeed-feeds elfeed-feeds))
  (elfeed-update-feed url))

;;;###autoload
(defun elfeed-update ()
  "Update all the feeds in `elfeed-feeds'."
  (interactive)
  (elfeed-log 'info "Elfeed update: %s"
              (format-time-string "%B %e %Y %H:%M:%S %Z"))
  (let ((elfeed--inhibit-update-init-hooks t))
    (mapc #'elfeed-update-feed (elfeed--shuffle (elfeed-feed-list))))
  (run-hooks 'elfeed-update-init-hooks)
  (elfeed-db-save))

;;;###autoload
(defun elfeed ()
  "Enter elfeed."
  (interactive)
  ;; elfeed-search.el is required at runtime.
  (declare-function elfeed-search-buffer "elfeed-search")
  (declare-function elfeed-search-mode   "elfeed-search")
  (switch-to-buffer (elfeed-search-buffer))
  (unless (eq major-mode 'elfeed-search-mode)
    (elfeed-search-mode)))

;; New entry filtering

(cl-defun elfeed-make-tagger
    (&key feed-title feed-url entry-title entry-link after before
          add remove callback)
  "Create a function that adds or removes tags on matching entries.

FEED-TITLE, FEED-URL, ENTRY-TITLE, and ENTRY-LINK are regular
expressions or a list (not <regex>), which indicates a negative
match.  AFTER and BEFORE are relative times (see
`elfeed-time-duration').  Entries must match all provided
expressions.  If an entry matches, add tags ADD and remove tags
REMOVE.  Call CALLBACK for each entry.

Examples,

  (elfeed-make-tagger :feed-url \"youtube\\\\.com\"
                      :add \\='(video youtube))

  (elfeed-make-tagger :before \"1 week ago\"
                      :remove \\='unread)

  (elfeed-make-tagger :feed-url \"example\\\\.com\"
                      :entry-title \\='(not \"something interesting\")
                      :add \\='junk)

The returned function should be added to `elfeed-new-entry-hook'."
  (let ((after-time  (and after  (elfeed-time-duration after)))
        (before-time (and before (elfeed-time-duration before))))
    (when (and add (symbolp add)) (setf add (list add)))
    (when (and remove (symbolp remove)) (setf remove (list remove)))
    (lambda (entry)
      (let ((feed (elfeed-entry-feed entry))
            (date (elfeed-entry-date entry))
            (case-fold-search t))
        (cl-flet ((match (r s)
                         (or (null r)
                             (if (listp r)
                                 (not (string-match-p (cl-second r) s))
                               (string-match-p r s)))))
          (when (and
                 (match feed-title  (elfeed-feed-title  feed))
                 (match feed-url    (elfeed-feed-url    feed))
                 (match entry-title (elfeed-entry-title entry))
                 (match entry-link  (elfeed-entry-link  entry))
                 (or (not after-time)  (> date (- (float-time) after-time)))
                 (or (not before-time) (< date (- (float-time) before-time))))
            (when add
              (apply #'elfeed-tag entry add))
            (when remove
              (apply #'elfeed-untag entry remove))
            (when callback
              (funcall callback entry))
            entry))))))

;; OPML

(defun elfeed--parse-opml (xml)
  "Parse XML (from `xml-parse-region') into `elfeed-feeds' list."
  (cl-loop for (tag attr . content) in (cl-remove-if-not #'listp xml)
           count tag into work-around-bug  ; bug#15326
           when (assoc 'xmlUrl attr) collect (cdr it)
           else append (elfeed--parse-opml content)))

;;;###autoload
(defun elfeed-load-opml (file)
  "Load feeds from FILE in OPML format into `elfeed-feeds'.
When called interactively, the changes to `elfeed-feeds' are
saved to your customization file."
  (interactive "fOPML file: ")
  (let* ((xml (elfeed-xml-parse-file file))
         (feeds (elfeed--parse-opml xml))
         (full (append feeds elfeed-feeds)))
    (prog1 (setf elfeed-feeds (delete-dups (copy-sequence full)))
      (when (called-interactively-p 'any)
        (customize-save-variable 'elfeed-feeds elfeed-feeds)
        (elfeed-log 'notice "%d feeds loaded from %s" (length feeds) file)))))

;;;###autoload
(defun elfeed-export-opml (file)
  "Export the current feed listing to OPML-formatted FILE."
  (interactive "FOutput OPML file: ")
  (with-temp-file file
    (let ((standard-output (current-buffer)))
      (princ "<?xml version=\"1.0\"?>\n")
      (xml-print
       `((opml ((version . "1.0"))
               (head () (title () "Elfeed Export"))
               (body ()
                     ,@(cl-loop for url in (elfeed-feed-list)
                                for feed = (elfeed-db-get-feed url)
                                for title = (or (elfeed-feed-title feed) "")
                                collect `(outline ((xmlUrl . ,url)
                                                   (title . ,title)))))))))))

(provide 'elfeed)

(unless nil
  ;; run-time only, so don't load when compiling other files
  (require 'elfeed-csv)
  (require 'elfeed-show)
  (require 'elfeed-search))

;;; elfeed.el ends here
