BOM weather interface

.gitignore

@@ -21,6 +21,9 @@ url/
 bookmarks
 request/
 
+# Weather forecast
+forecast
+
 # Custom file
 custom.el
 

screens/dashboard.el

@@ -113,7 +113,7 @@
 						      ("RSS" elfeed "r")
 						      ("Terminal" theurgy-bottom-shell "t")
 						      ("Gomuks" theurgy-gomuks-workspace "G")
-						      ("Weather" theurgy-show-weather "w")))))
+						      ("Weather" theurgy-weather "w")))))
 						:align center
 						:width 20))
 		      (grid-make-box `(:content ,(concat
@@ -144,7 +144,7 @@
 			     (grid-make-column (list (grid-make-box `(:content ,(concat
 										 (enlight-menu
 										  '(("Userland"
-										     ("Dired" (dired "~") "d")
+										     ("Weather" theurgy-weather "w")
 										     ("RSS" elfeed "r")
 										     ("Terminal" theurgy-bottom-shell "t")
 										     ))))

userland/weather.el

@@ -0,0 +1,162 @@
+;;; weather.el --- Fetch and display the weather from bom.gov.au -*- lexical-binding: t -*-
+
+
+;; This file is not part of GNU Emacs
+
+;; 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:
+
+;; Reverse-engineered API docs are available here https://trickypr.github.io/bom-weather-docs/
+;; This code depends on request.el
+
+;;; Code:
+
+(defcustom theurgy-geohash
+  ""
+  "The geohash used for fetching forecast data from BOM. You can manually find this by going to https://api.weather.bom.gov.au/v1/locations?search=<suburb-name>, or you can get a nicer interface for it with \\[theurgy-weather-find-geohash]."
+  :type 'string
+  :group 'theurgy
+  :group 'theurgy-weather)
+
+(defvar bom-api "https://api.weather.bom.gov.au/v1/")
+
+(defun theurgy-weather-find-geohash (search-term)
+  "Search for SEARCH-TERM and then return possible geohash candidates."
+  (interactive "sSearch term (Suburb or Postcode): ")
+  (when (> 4 (length search-term))
+    (error "Search term must be greater than 3 characters (don't ask me)"))
+  (request (concat bom-api "locations?search=" search-term)
+    :parser 'json-read
+    :success (cl-function
+	      (lambda (&key data &allow-other-keys)
+		(let* ((res (cdr (assoc 'data data)))
+		       (candidates (mapcar (lambda (alst)
+					     (cons (concat
+						    (cdr (assoc 'name alst)) ", "
+						    (cdr (assoc 'state alst)) ", "
+						    (cdr (assoc 'postcode alst)))
+						   (cdr (assoc 'geohash alst))))
+					   res)))
+		  (customize-set-variable 'theurgy-geohash (cdr (assoc (completing-read "Select Location: " candidates) candidates))))))))
+
+(defvar forecast-timer nil)
+(defvar forecast-location "forecast") ;; The location of the cached forecast, related to the emacs user directory
+
+(defun theurgy-weather-fetch-forecast ()
+  "Fetch and save the weather forecast."
+  (interactive)
+  (request
+    (concat bom-api "locations/" theurgy-geohash "/forecasts/daily")
+    :parser 'json-read
+    :success (cl-function
+	      (lambda (&key data &allow-other-keys)
+		(save-excursion
+		  (find-file (concat user-emacs-directory forecast-location))
+		  (delete-region (point-min) (point-max))
+		  (insert (format "%S" (mapcar (lambda (alst)
+						 (cons (let ((d (parse-time-string (cdr (assoc 'date alst)))))
+							 (list (nth 3 d) (nth 4 d) (nth 5 d)))
+						       (assq-delete-all 'date alst)))
+					       (cdr (assoc 'data data)))))
+		  (save-buffer)
+		  (kill-buffer))))))
+
+(defun current-date ()
+  "Get the current date as a list."
+  (let ((d (decode-time (current-time))))
+    (list (nth 3 d) (nth 4 d) (nth 5 d))))
+
+(defun today+ (days)
+  "Date list for today + DAYS."
+  (let* ((sec (+ (* days 86400) (time-convert (current-time) 'integer)))
+	 (d (decode-time sec)))
+    (list (nth 3 d) (nth 4 d) (nth 5 d))))
+
+(defun prompt-date ()
+  "Prompt the user for a date."
+  (let ((d (parse-time-string (org-read-date))))
+    (list (nth 3 d) (nth 4 d) (nth 5 d))))
+
+(defun theurgy-weather-get-for-date (date)
+  "Get weather for a particular DATE."
+  (let* ((forecast-data (read (with-temp-buffer
+				(insert-file-contents (concat user-emacs-directory forecast-location))
+				(buffer-string))))
+	 (day (assoc date
+		     forecast-data)))
+    day))
+
+(defun theurgy-quick-forecast (date)
+  "Quick forecast for DATE."
+  (let ((forecast (theurgy-weather-get-for-date date)))
+    (message (format "%s - %s degrees. %s"
+		     (cdr (assoc 'temp_min forecast))
+		     (cdr (assoc 'temp_max forecast))
+		     (cdr (assoc 'short_text forecast))))))
+
+(defun theurgy-weather-quick ()
+  "Show the forecast as a message."
+  (interactive)
+  (theurgy-quick-forecast (prompt-date)))
+
+(defun theurgy-start-forecast-timer ()
+  "Start the timer for periodically retrieving the weather forecast."
+  (interactive)
+  (theurgy-weather-fetch-forecast)
+  (unless forecast-timer
+    (when (timerp forecast-timer)
+      (cancel-timer forecast-timer))
+    (setq forecast-timer (run-at-time t (* 60 30) (theurgy-weather-fetch-forecast)))))
+
+(theurgy-start-forecast-timer)
+
+(defun theurgy-weather-insert-forecast (fc)
+  "Insert provided forecast FC in the current buffer, as org markup."
+  (let ((date (car fc)))
+    (insert (format "* %s/%s/%s - %s\n" (nth 0 date) (nth 1 date) (nth 2 date) (cdr (assoc 'short_text fc))))
+    (insert (format "%s\n" (cdr (assoc 'extended_text fc))))
+    (insert (format "- %s-%s°C\n"
+		    (cdr (assoc 'temp_min fc))
+		    (cdr (assoc 'temp_max fc))))
+    (insert (format "- %s%% Chance of Rain (%s-%smm)\n"
+		    (cdr (assoc 'chance (assoc 'rain fc)))
+		    (cdr (assoc 'lower_range (assoc 'amount (assoc 'rain fc))))
+		    (cdr (assoc 'upper_range (assoc 'amount (assoc 'rain fc))))))
+    (insert (format "- %s UV\n"
+		    (cdr (assoc 'category (assoc 'uv fc)))))
+    (insert (format "- %s Fire Danger\n"
+		    (cdr (assoc 'fire_danger fc))))
+    (insert "\n")))
+
+(defun theurgy-weather ()
+  "Show weather information in a new buffer."
+  (interactive)
+  (let ((buf (generate-new-buffer "*Weather*")))
+    (with-current-buffer buf
+      (delete-region (point-min) (point-max))
+      (org-mode)
+      (let* ((today (theurgy-weather-get-for-date (current-date)))
+	     (tomorrow (theurgy-weather-get-for-date (today+ 1)))
+	     (after-tomorrow (theurgy-weather-get-for-date (today+ 2))))
+	(theurgy-weather-insert-forecast today)
+	(theurgy-weather-insert-forecast tomorrow)
+	(theurgy-weather-insert-forecast after-tomorrow))
+      (setq buffer-read-only t))
+    (switch-to-buffer buf)))
+
+(provide 'weather)
+
+;;; weather.el ends here