;;; Commentary:
;;
;; This package adds the ability to sync org-mode tasks with
;; Toodledo, a powerful web-based todo list manager that welcomes 3rd
;; party integrations.  (See http://www.toodledo.com/)
;;
;; This version of `org-toodledo' utilizes version 2.0 of the Toodledo API. 
;;
;; SYNCHRONIZING FOR THE FIRST TIME
;; --------------------------------
;;
;; The first step in using org-toodledo is to initialize a file and
;; synchronize tasks.  Simply create a new file, change the mode to
;; `org-mode', then call `org-toodledo-initialize'.  This will create
;; a new heading called "TASKS" (by default) and will import all
;; non-deleted tasks from Toodledo as sub-headings beneath "TASKS".
;;
;; If you already have an existing list of tasks in org file, open the
;; org file first.  Move the cursor to the headling where you want
;; imported tasks from Toodledo to be inserted into the buffer.  Call
;; `org-toodledo-initialize'.  This will import all tasks from the
;; server as well as pushing existing tasks in the org file back to
;; the server.
;; 
;; Once an org-file has been initialized, the heading selected will
;; be given a few Toodledo specific properties that are used to track
;; the status of synchronization:
;;
;;   * TASKS 
;;     :PROPERTIES:
;;     :ToodledoLastSync: 1315343842
;;     :ToodledoLastEdit: 1315337478
;;     :ToodledoLastDelete: 1314972230
;;     :OrgToodledoVersion: 2.3
;;     :END:
;;
;; This is referred to as the 'base Toodledo entry'.
;;
;; SYNCHRONIZING TASKS
;; -------------------
;;
;; The local org-file can be synchronized with the server at any time
;; by calling `org-toodledo-sync'.  When called, the following steps
;; are performed:
;; 
;;   1. Tasks added to the server since the last sync are downloaded
;;      and inserted as sub-headings to the Toodledo base heading (has
;;      the `ToodledoLastSync' property)
;;
;;   2. Tasks modified on the server are compared against the local
;;      copy.  If the local copy was not modified since the last sync,
;;      the local copy is updated.  If local copy was modified, the
;;      server copy is inserted *after* the local copy as a duplicate.
;;      The user must manually merge any changes
;;
;;   3. Tasks deleted on the server are removed entirely from the
;;      local org file.
;;
;;   4. Tasks modified locally are pushed to the server as edits.
;;
;;   5. Tasks created and not yet prseent on the server are pushed as
;;      new tasks.
;;
;;   6. Tasks marked for deletion are deleted from the server, and
;;      then purged from the local file.
;;
;; Changes to tasks are automatically detected by computing a hash of
;; the task fields.  This hash is computed and saved as a property of
;; the task on sync.  When the next sync occurs, the hash value is
;; compared and if it differs, the task is considered modified.  This
;; eliminates the need for the user to mark tasks as modified or
;; remembere which tasks have changed -- it's all automatic!
;;
;; Note that `org-toodledo-sync' scans the entire file for tasks, not
;; just subheadings of the base entry.
;;
;; ADDING NEW TASKS
;; ----------------
;;
;; To add a new task on the server, just create a new headline
;; anywhere in the org file and give the headline a TODO keyword.
;; When ready, call `org-toodledo-sync' to push new tasks to the
;; server.
;;
;; DELETING TASKS
;; --------------
;;
;; Tasks cannot simply be killed from the org-file like text if the
;; were already synced with the server since they will just come back
;; the next time `org-toodledo-sync' is called.  Instead, they must be
;; marked as deleted by calling `org-toodledo-mark-task-deleted'.  Call
;; this function from any point within the task.  At the next sync, 
;; the task will be deleted from the server and then killed from the 
;; local file.
;;
;; Note that it may not be necessary to delete tasks in this way.  Instead
;; complete the task and let Toodledo archive completed tasks.
;;
;; TOODLEDO FIELDS
;; ---------------
;;
;; The table lists the possible Toodledo fields and how they are
;; mapped to org-mode style tasks:
;;
;; | Toodledo Field | Org-mode               | Comments                                     |
;; | id             | Property :ToodledoID:  | If present, this task was previoiusly synced |
;; | title          | Heading                | Heading minus TODO state, priority and tags  |
;; | status         | TODO state             | See `org-toodledo-status-to-org-map'         |
;; | startdate      | SCHEDULED              | startdate/startime are GMT                   |
;; | starttime      | SCHEDULED              |                                              |
;; | duedate        | DEADLINE               | duedate/duetime are GMT                      |
;; | duetime        | DEADLINE               |                                              |
;; | completed      | CLOSED                 | Timestamp when the task was marked completed |
;; | repeat         | Repeat interval        |                                              |
;; | repeatfrom     |                        |                                              |
;; | context        | Tag                    | Context string "Work" becomes a tag :@Work:  |
;; | modified       | Property :Modified:    | Timestamp when last modifed (set by server)  |
;; | folder         | Property :Folder:      |                                              |
;; | goal           | Property :Goal:        |                                              |
;; | priority       | Priority               | 3=>A, 2=>B, 1=>C, -1,0 => D                  |
;; | note           | Body                   | Body of the task minus the properties        |
;; | length         | Effort                 |                                              |
;; | parent         |                        | Links tasks parent/child                     |
;; | tag            | Tag                    | org-mode tags, note context is also a tag    |
;;
;; TODO STATES
;; -----------
;;
;; The TODO states from Toodledo are mapped to org-mode states via the
;; `org-toodledo-status-to-org-map' alist.   This can be customized to
;; choose your own TODO states, but all 10 states from Toodledo should
;; be mapped, even if only a subset are used in org-mode.
;;
;; In order to cycle through all the states recognized by Toodledo,
;; put a line like the following somewhere in your org file:
;;
;;   #+SEQ_TODO: TODO(t) DELEGATED(g) SOMEDAY(s) WAITING(w) | DONE(d) CANCELLED(c) REFERENCE(r) 
;;
;; CONTEXTS
;; --------
;;
;; Toodledo 'Contexts' allow you to split tasks into contexts such as
;; Work and Home.  Contexts are mapped to org tags with the '@' keyword,
;; :@Work: and :@Home:.
;;
;; Currently only contexts already on the server are recognized.  Setting
;; the task context of :@Phone: when Phone is not a valid context will 
;; loose the context.
;; 
;; SUBTASKS
;; --------
;;
;; Sub-tasks are supported by Toodledo with a Pro account subscription.  
;; When enabled, a 2-level task hierarchy is supported:
;;
;;   * TODO Write a best-selling novel
;;   ** DONE Make an outline
;;   ** WAITING Call Susan about the contract
;;   ** TODO Finish writing
;;   ** TODO Profit
;;
;; The parent/child relationship is tracked dynamically at the time
;; of sync, looking for the next heading up for each task, and if present
;; and a task, link the task to the parent.
;;
;; Bi-directional synchronization is fully supported.
;;
;; If the account is not a Pro account, subtasks will still be synced
;; to the server, but the parent/child relationship is not.  This
;; yields a flat list of tasks on the server.  Note that the hierarchy
;; in the org file is still maintained even though not on the server.
;;
;; NOTE: A hierarchy of TODO items of more than 2 levels is not supported
;; by the server.  If 3 or more levels is present, all children will
;; appear directly beneath the top-most TODO item:
;;
;;   org-mode:  
;;      * TODO Level 1 item
;;      ** WAITING Level 1.1 item
;;      *** DONE Level 1.1.1 item
;;      ** DONE Level 1.2 item
;;      *** DONE Level 1.2.1 item
;;
;;   server:
;;      * TODO Level 1 item
;;      ** WAITING Level 1.1 item
;;      ** DONE Level 1.1.1 item
;;      ** DONE Level 1.2 item
;;      ** DONE Level 1.2.1 item
;;
;; Note that the hierarchy is preserved in the org-mode file, it just
;; displays with the children flattened on the server.
;;
;; MISCELLANEOUS NOTES
;; -------------------
;;
;;  - Doesn't do lots of error trapping. Might be a good idea to
;;    version-control your Org file.
;;
;;  - Verify handling of other tags that are not context
;;  
;;  - The body of a task is stored as the Toodledo note.  May get
;;    confused by asterisks, so don't use any starting asterisks in
;;    your body text.  (or anything that looks like an Org headline).
;;
;;  - w3mexcerpt.el inlcudes things needed things from w3m (since w3m
;;    requires things which require things which require things which
;;    require an executable which is no longer readily
;;    available.). (sachac)
;;
;;  - By default, save will ask to sync with Toodledo.  This can
;;    behavior can be changed via `org-toodledo-sync-on-save'.
;;
;; FUTURE WORK
;; -----------
;;
;; ** TODO Feature Requests: highest priority at top
;; 
;; [ ] access to toodledo via proxy would also be good for those
;;     inside proxy based firewalls. (stophlong)
;; 
;; [ ] Add a 'purge-completed-tasks' function -- once these tasks have
;;     been synced to the server, kill them locally (since they are
;;     backed up on toodledo).  Alternatively, move them to an archive
;;     file.  (cjwhite)
;;
;; [ ] Option to restrict synchronization to just sync tasks under the
;;     the base Toodledo entry.  (cjwhite)
;;
;; [ ] Support tasks across all agenda files.  (cjwhite)
;;

;;; Change Log:
;;
;; 2011-09-07  (cjwhite)
;; - First release for general distribution based on API 2.0
;;
;; 2011-09-18  (cjwhite)
;; - (Bug fix) Properly create contexts that are missing on the server. (cjwhite)
;; - (Bug fix) Eliminate hyphens in the tag/properties that are saved (cjwhite)
;; - Implemented sub-tasks -- requires pro account subscription (cjwhite)
;; - Added customization variable `org-toodledo-sync-import-new-tasks'
;;
;; 2011-09-24  (cjwhite)
;; - Use https if pro subscription and patch installed (url-http appears broken
;;   for POSTs with data and https, at least on my box).  To enable, apply the 
;;   patch as follows:
;;       $ cd $emacs_install_dir/lisp/url
;;       $ patch < $path_to_patch/url-http.el.emacs-23.3.patch
;;   Then in emacs:
;;       M-x byte-compile-file $emacs_install_dir/lisp/url/url-http.el
;;   This patch seems to apply cleanly to 23.2 as well, but is not tested there.
;;   Search below for "bugreport" for more details and bug references.
;;
;; - Added `org-toodledo-run-tests' to load and run tests in org-toodledo-test.el.
;;   This uses the active account, creating/modifying/deleting tasks with the
;;   prefix 'ORGTOODLEDOTEST'.  All other tasks are ignored, so it *should* operate
;;   cleanly on an active toodledo account with multiple tasks.  If you run
;;   this and it does not pass all tests, please let me know  (cjwhite)
;;   
;; 2011-09-26  (cjwhite)
;; - Bug fix for checking boundp (myuhe)
;; - Support special chars (verified titles/notes) (myuhe)
;; - Added `org-toodledo-inhibit-https' to disable https
;;
;; 2011-09-29  (cjwhite)
;; - Bug fix: marking a task completed on the server did not update locally
;;
;; 2011-10-16  (cjwhite)
;; - Bug fix: first time sync of tasks with folders failed with org-mode 6.33x
;;
;; 2011-12-05  (cjwhite)
;; - Bug fix: folder / id mapping was reversed
;; - Bug fix: added require for aput / assoc
;; - Properly clear fields that are not set locally, ensuring they get cleared on server
;;
;; 2012-01-29  (cjwhite) - Version 2.2.0
;; - Added support for starttime / duetime (merged in partical changes for myuhe).  Note
;;   that the web site does not seem properly handle timezones.  The time in org-mode
;;   is properly converted to a unix timestamp (adjusting for timezone) and sent to the
;;   server, but the displayed time on toodledo.com and in apps (at least iPad app) is
;;   the time component in GMT, not the timezone set in the account settings.  Waiting
;;   for a response from toodledo.com on this.
;;
;; - Added `org-toodledo-flatten-all-tasks' which disables parent/child tasking.
;;   Set to true if you have more than 2 levels and wish to sync tasks to the server
;;   as a flat list at least for backup.
;;
;; - Improved debug logging, use `org-toodledo-toggle-debug' to turn on debug logging
;;
;; - Updated `org-toodledo-run-tests' to use a test account instead of the users account.
;;
;; 2012-01-30  (cjwhite) - Version 2.3
;; - Bug fix - major problem found whereby sync / modified times would be off just slightly
;;   when syncing local changes up to the server.  This would make it look like the local
;;   task was still modified even after sending it up to the server.  As such, any changes
;;   to the task on the server would result in duplicate tasks in org-mode on the next
;;   sync, because that's how changes on both sides are handled.  As part of this fix
;;   I completely eliminated the per task Modified and Sync properities as these are
;;   pretty much unneeded because of the detection of changes by the hash code
;;
;; - Bug fix for startdate / duedate.  These were probably working ok, but may have
;;   misbehaved if the timezone were more than 12h off GMT, which I think can only happen
;;   in a very few rare cases.  
;;
;; - Fixed up the starttime / duetime.  Turns out that toodledo.com treats these times
;;   like alarms, so a duetime of "7:00am" is 7am, regardless of what timezone you are
;;   in.  That means you can change your timezone at will and the duetime is still
;;   7am *local* time.  This is stored as an offset from midnight GMT on the due date.
;;
;; - Added a version variable / function `org-toodledo-version'.  This is checked on 
;;   sync and may do some cleanup of things that have changed in various versions.  This
;;   will make it easier down the road to detect what version someone is running as well.
;;
;; - Added some delays into the devtest -- seems it may have been syncing back and forth
;;   too fast (within the same second) such that changes may not be perceived
;;
;; - Added a lot more debug messages to help with timing / sync problems
;;
;; 2012-02-09  (cjwhite) - Version 2.4
;; - Added new patch for url-http.  This should address at least some of the spurious
;;   problems that caused an XML parse error.  If the XML response from the server
;;   was just around 1200 bytes, url-http was not handling it properly and cutting off
;;   the last few bytes.  See the Installation instructions below for installing the patches
;;
;; 2012-02-09  (cjwhite) - Version 2.5
;; - Bug fix - requesting a token was still using https even if `org-toodledo-inhibit-https'
;;   was set to true.
;;
;; 2012-02-19  (cjwhite) - Version 2.6
;; - Added `org-toodledo-agenda-mark-task-deleted' function and suggested binding
;;   to mark tasks deleted from agenda mode.  See Installation for info
;;
;; - When a task is marked for deleted, move the task to a task titled
;;   "Deleted Tasks" to get it out of the way
;;
;; - Handle more than 2-levels of hierarchy by flatting all children.  The hierarchy
;;   will be preserved.  See SUBTASKS above for more details.
;;
;; - Realign all tags after sync according to the width of the current window
;;
;; - Better handling of 'duplicate' tasks -- When a task has been
;;   modified locally and on the server, the user is prompted to
;;   resolve the difference by selecting the local copy, the server
;;   copy, or editing and resolving manually
;;
;; 2012-02-19  (cjwhite) - Version 2.6.1
;; - Fix for use of http vs https
;;
;; 2012-02-20  (cjwhite) - Version 2.7
;; - Added support for tags, they are added as org-mode tags.
;;
;; - Fixed handling of tasks with an embedded '*' - this would
;;   completely mess things up of the '*' was the first char of
;;   a line
;;  
;; - Added customization `org-toodledo-indent-task-note', set to t
;;   by default.  This indents the note according to the task level.
;;   This has a cleaner look and reduces the chance of errors like
;;   the above with '*' as the first char.
;;
;; - Better detection of actual note text, eliminating blank lines
;;
;; - Fixed handling of "Invalid Key" error that indicates the token
;;   needs to be refreshed
;;
;; - Fix bug for subtasks if parent is not at top-level
;;
;; 2012-03-13  (cjwhite) - Version 2.8
;; - Significantly better error handling for adding, editng and deleting
;;   tasks during synchronization.  If errors occurred, only the offending
;;   task should be affected, allowing all other tasks to be synced.  The
;;   specific error message is logged for better debugging.
;;
;; - Added customization `org-toodledo-folder-support-mode'.  Setting this
;;   to `heading' will create heading tasks according to the folder name
;;   and put all tasks in that folder as child tasks of the heading.  
;;   No support yet for creating folders in org mode, create the folders
;;   on toodledo.com first and put at least one task in the folder.  This
;;   feature is somewhat experimental.
;; 
;; - Improved handling of token expiration / invalid key errors
;; 
;; - Added simulation mode for testing without actually hitting the server. 
;;   Allows simulating error conditions that are potentially hard to 
;;   reproduce with a real connection to the server.  See org-toodledo-sim.el
;;   and org-toodledo-test.el where sim calls are used.
;;
;; 2012-07-21  (cjwhite) - Version 2.9
;; - Added 'length' to the list of fields to ignore if 0 for computing
;;   a hash
;;
;; - Removed deprecated/obsolete use of aput/adelete from assoc.el
;; 
;; - Hopefully finally fixed spurious issue where syncing resulted in
;;   "Failed to find todo entry...".  When processing incoming tasks 
;;   from the server, process parent tasks *then* child tasks.  It seems
;;   in some cases the child task may show up first before the parent
;;   is known.

;;; Installation:
;;
;; 1. Required emacs packages:
;;      * `w3m' or `w3mexcerpt' -- see Notes below
;;      * `http-post-simple' -- http://www.emacswiki.org/emacs/http-post-simple.el
;;
;; 2. Put this file in your load path, byte compile the file for best
;;    performance, see `byte-compile-file'.
;;
;; 3. Put the following in your .emacs:
;;
;;    (push "<path-to-this-file>" load-path)
;;    (require 'org-toodledo)
;;    (setq org-toodledo-userid "<toodledo-userid>")      << *NOT* your email!
;;    (setq org-toodledo-password "<toodled-password>")
;;
;;    ;; Useful key bindings for org-mode
;;    (add-hook 'org-mode-hook
;;           (lambda ()
;;             (local-unset-key "\C-o")
;;             (local-set-key "\C-od" 'org-toodledo-mark-task-deleted)
;;             (local-set-key "\C-os" 'org-toodledo-sync)
;;             )
;;           )
;;    (add-hook 'org-agenda-mode-hook
;;           (lambda ()
;;             (local-unset-key "\C-o")
;;             (local-set-key "\C-od" 'org-toodledo-agenda-mark-task-deleted)
;;             )
;;           )
;;
;; 4. Install 2 patches for url-http.el (these are written for 23.3, but may
;;    work for other versions, if not patch manually, as the diffs are
;;    not that complex)
;;
;;    url-http.el.emacs-23.3.patch 
;;       - addresses http://debbugs.gnu.org/cgi/bugreport.cgi?bug=9592, 
;;         involving attempted connection reuse
;;       - addresses http://debbugs.gnu.org/cgi/bugreport.cgi?bug=8931,
;;         problem when sending a request with no data
;;         
;;    url-http.el.emacs-23.3.patch2 
;;       - addresses http://debbugs.gnu.org/cgi/bugreport.cgi?bug=10768
;;         fixes a problem with responses that are barely longer than 1
;;         TCP data packet (about 1200 bytes)
;;    
;;    To install the patches:
;;       $ cd $emacs_install_dir/lisp/url
;;       $ patch < $path_to_patch/url-http.el.emacs-23.3.patch
;;       $ patch < $path_to_patch/url-http.el.emacs-23.3.patch2
;;
;;    Then in emacs:
;;       M-x byte-compile-file $emacs_install_dir/lisp/url/url-http.el
;;
;;    This patch seems to apply cleanly to 23.2 as well, but is not tested there.
;;