DROP TABLE IF EXISTS notes;
DROP TABLE IF EXISTS note_relationships;
DROP TABLE IF EXISTS pages;
DROP TABLE IF EXISTS page_relationships;
DROP TABLE IF EXISTS favorites;

CREATE TABLE notes (
    id INTEGER PRIMARY KEY AUTOINCREMENT,
    uuid TEXT NOT NULL UNIQUE,
    notetype TEXT
);

CREATE TABLE pages (
    id INTEGER PRIMARY KEY AUTOINCREMENT,
    slug text NOT NULL UNIQUE,
    note_id INTEGER,
    FOREIGN KEY (note_id) REFERENCES notes (id) ON DELETE NO ACTION ON UPDATE NO ACTION
);

CREATE TABLE note_relationships (
    note_id INTEGER NOT NULL,
    parent_id INTEGER NOT NULL,
    position INTEGER NOT NULL,
    nature TEXT NOT NULL,
    FOREIGN KEY (note_id) REFERENCES notes (id) ON DELETE NO ACTION ON UPDATE NO ACTION,
    FOREIGN KEY (parent_id) REFERENCES notes (id) ON DELETE NO ACTION ON UPDATE NO ACTION
);

CREATE TABLE page_relationships (
    note_id INTEGER NOT NULL,
	page_id INTEGER NOT NULL,
	FOREIGN KEY (note_id) references notes (id) ON DELETE NO ACTION ON UPDATE NO ACTION,
	FOREIGN KEY (page_id) references pages (id) ON DELETE NO ACTION ON UPDATE NO ACTION
);

INSERT INTO notes (id, uuid, notetype) VALUES
	   (1, "U1", "root"),
	   (2, "U2", "note"),
	   (3, "U3", "note"),
	   (4, "U4", "note"),
	   (5, "U5", "note"),
	   (6, "U6", "note"),
	   (7, "U7", "note"),
	   (8, "U8", "note");

INSERT INTO note_relationships (note_id, parent_id, position, nature) VALUES
	   (2, 1, 1, "note"),
	   (3, 1, 2, "note"),
	   (4, 3, 1, "note"),
	   (5, 3, 2, "note"),
	   (6, 5, 1, "note"),
	   (7, 4, 1, "note"),
	   (8, 7, 1, "note");


SELECT id, uuid, parent_id, parent_uuid, notetype
FROM (
  WITH RECURSIVE parents (
    id, uuid, parent_id, parent_uuid, notetype, cycle
  )

  AS (
    SELECT notes.id, notes.uuid,
	       note_parents.id,
		   note_parents.uuid,
		   notes.notetype,
		   ','||notes.id||','
      FROM notes
	    INNER JOIN note_relationships
		  ON notes.id = note_relationships.note_id
		  AND notes.notetype = 'note'
		INNER JOIN notes as note_parents
		  ON note_parents.id = note_relationships.parent_id
        WHERE notes.id = 4
    
    UNION
	SELECT DISTINCT notes.id,
		   notes.uuid,
	       next_parent.id,
		   next_parent.uuid,
		   notes.notetype,
           parents.cycle||notes.id||','
      FROM notes
      INNER JOIN parents
	    ON parents.parent_id = notes.id
	  LEFT JOIN note_relationships
	    ON note_relationships.note_id = notes.id
	  LEFT JOIN notes as next_parent
	    ON next_parent.id = note_relationships.parent_id
      WHERE parents.cycle NOT LIKE '%,'||notes.id||',%'
  )

  SELECT * FROM parents);

-- Possible outcomes epending on the 'WHERE notes.id' clause in the root SELECT (first value is passed in):
-- 8, 7, 4, 3, 1
-- 6, 5, 3, 1
-- 2, 1
-- 4, 3, 1
-- 1 should result in no return (root notes aren't returned by themselves; they exist only so that
-- valid note reversals can find their parent page objects.