Add db

graph-notes-db.el

@@ -0,0 +1,105 @@
+;;; graph-notes-db --- The sqlite backend for graph notes -*- lexical-binding: t; -*-
+
+;; Copyright © 2020 Simon Bugge Siggaard <buggaarde@gmail.com>
+
+;; Author: Simon Bugge Siggaard <buggaarde@gmail.com>
+;; URL: https://github.com/buggaarde/graph-notes
+;; Keywords: non-hierarchical, notes, note, notetaking, productivity, creativity
+;; Version: 0.1
+;; Package-Requires: ((emacs "26.1") (buttercup "1.21") (dash "2.17") (f "0.20.0") (s "1.12.0") (emacsql "3.0.0") (emacsql-sqlite "1.0.0"))
+
+;; 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, 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 GNU Emacs; see the file COPYING.  If not, write to the
+;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+;; Boston, MA 02110-1301, USA.
+
+;;; Commentary:
+
+;;; Code:
+(require 'emacsql)
+(require 'emacsql-sqlite)
+
+;;;; Schemas:
+(defvar graph-notes-db--tags-schema
+  '([(id integer :primary-key)
+	 file-name])
+  "The table containing all graph-note tags.
+
+The table also contains the name of the file representing the tag.")
+
+(defvar graph-notes-db--links-schema
+  '([(id integer :primary-key)
+	 (from-tag-id integer)
+	 (to-tag-id integer)]
+	(:foreign-key [from-tag-id] :references tags [id])
+	(:foreign-key [to-tag-id] :references tags [id]))
+  "The table connects all links between tags.")
+
+(defvar graph-notes-db--synonyms-schema
+  '([(id integer :primary-key)
+	 name
+	 (tag-id integer)]
+	(:foreign-key [tag-id] :references tags [id]))
+  "The table associates string names with the more abstract foreign-key tag id.")
+
+;;;; Helper functions:
+(defun graph-notes-db--backlinks-to-file (db file-name)
+  "Return all tags containing backlinks to tag given by file name.
+
+DB is the sqlite database.
+FILE-NAME is the file name."
+  (emacsql db [:select [links.from-tag-id]
+			   :from links
+			   :inner-join tags
+			   :on (= links.to-tag-id tags.id)
+			   :where (= tags.file-name $r1)]
+		   file-name))
+
+(defun graph-notes-db--tags-in-file (db file-name)
+  "Return all tags in given file.
+
+DB is the sqlite database.
+FILE-NAME is the file name."
+  (emacsql db [:select [links.to-tag-id]
+			   :from links
+			   :inner-join tags
+			   :on (= links.from-tag-id tags.id)
+			   :where (= tags.file-name $r1)]
+		   file-name))
+
+(defun graph-notes-db--tag-synonyms (db tag)
+  "Return all synonyms for the given tag.
+
+DB is the sqlite database.
+TAG is the tag id."
+  (emacsql db [:select [synonyms.name]
+			   :from synonyms
+			   :inner-join tag
+			   :on (= synonyms.tag-id tags.id)
+			   :where (= tags.id $s1)]
+		   tag))
+
+(defun graph-notes-db--tag-id-from-file-name (db file-name)
+  "Return the id of the tag corresponding to the current file name.
+
+DB is the sqlite database.
+FILE-NAME is the file name."
+  (emacsql db [:select [id]
+			   :from tags
+			   :where (= file-name $r1)]
+		   file-name))
+
+(provide 'graph-notes-db)
+;;; graph-notes-db.el ends here