From e7c08b088d52cdfbc00ce41801b5e6895b80ddc7 Mon Sep 17 00:00:00 2001
From: Daniel Borchmann <daniel@algebra20.de>
Date: Mon, 1 Jul 2024 20:07:58 +0200
Subject: [PATCH] Introduce helper function to format Ledger CLI output as Org
 table

This function is ideal, but it's doing the job.  It can be used to
format output of calls to ledger as follows:

    #+begin_src emacs-lisp :results value raw table
    (db/ledger-cli-to-org-table-list
     (concat "ledger -f finance.ledger "
             "--period monthly --depth 2 "
             "--display 'd >= [2024-07-01]' "
             "--empty "
             "lisp ^Expense"))
    #+end_src
---
 site-lisp/db-org.el | 47 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 47 insertions(+)

diff --git a/site-lisp/db-org.el b/site-lisp/db-org.el
index 5971434..34baad8 100644
--- a/site-lisp/db-org.el
+++ b/site-lisp/db-org.el
@@ -1076,6 +1076,53 @@ _q_ → Quit this hydra"
   ("q" (message "Abort") nil)
   ("C-g" (message "Abort") nil))
 
+(defun db/ledger-cli-to-org-table-list (command)
+  "Run ledger COMMAND and convert the result to Org table list.
+
+COMMAND is expected to be a call to ledger-cli and its `lisp'
+subcommand, the result of which is a list of transactions.  This
+list is converted in such a way that Org can display it as table,
+where the rows are all accounts contained in the result of
+COMMAND, and where the columns are the individual transactions,
+headlined with their date."
+  ;; XXX: this implementation is certainly not ideal
+  (let* ((data (->> command
+                    shell-command-to-string
+                    read-from-string    ; XXX: this needs some error handling
+                    car
+                    ;; Format time and remove unnecessary data
+                    (-map #'(lambda (row)
+                              (list (format-time-string "%F" (nth 2 row))
+                                    (-map #'(lambda (entry)
+                                              (list (nth 1 entry)
+                                                    (nth 2 entry)))
+                                          (-drop 5 row)))))))
+         (months (-map #'-first-item data))
+         funds
+         result)
+
+    (dolist (row data)
+      (let ((month (-first-item row)))
+        (dolist (entry (-second-item row))
+          (let ((fund (-first-item entry))
+                (value (-second-item entry)))
+            (setf (alist-get month (alist-get fund funds nil nil #'string=) nil nil #'string=)
+                  value)))))
+
+    (push (cl-list* "" months) result)
+    (push (cl-list* " " (-repeat (length data) "<r>")) result)
+    (push 'hline result)
+
+    (dolist (fund (-sort #'string< (-map #'-first-item funds)))
+      (push (cl-list* fund
+                      (-map #'(lambda (month)
+                                (alist-get month (alist-get fund funds nil nil #'string=)
+                                           "0.00€" nil #'string=))
+                            months))
+            result))
+
+    (reverse result)))
+
 
 ;;; Checklist Handling