CREATE TABLE tasks(
	task_id INTEGER PRIMARY KEY,
	title TEXT NOT NULL UNIQUE,
	active_id INTEGER,
	status TEXT NOT NULL DEFAULT 'backlog',
	creation_date DATE DEFAULT (date('now')),
	due_date TEXT,
	    CHECK (
	        due_date IS NULL OR 
	        due_date GLOB '????-??-??'
		)
);

-- Basically when we add a new task the active id is set
-- but when a task is done we want it to be able to be null so we need to increment
-- COALESCE is a cool function that returns the first non-null argument which takes care of empty
-- active task list
CREATE TRIGGER autoinc_active_id
AFTER INSERT ON tasks
BEGIN
	UPDATE tasks SET active_id = (SELECT COALESCE((SELECT MAX(active_id) FROM tasks) + 1, 1)) WHERE task_id=NEW.task_id;

END;

CREATE TABLE entries(
	entry_id INTEGER PRIMARY KEY,
	task_id INTEGER NOT NULL REFERENCES tasks(task_id),
	body TEXT NOT NULL,
	creation_date DATETIME DEFAULT (datetime('now', 'localtime'))
);

INSERT INTO tasks (title) VALUES ('test1'), ('test2'), ('test3');
INSERT INTO entries (task_id, body) VALUES (1, 'this is an entry for test1'), (2, 'this is an entry for test2'), (3, 'this is an entry for test3');

UPDATE tasks SET status = 'today' WHERE title = 'test2';

CREATE VIEW all_info AS SELECT * FROM entries JOIN tasks ON entries.task_id = tasks.task_id;