Index: db-scripts/triggers/compute_daily_completion.sql
===================================================================
--- db-scripts/triggers/compute_daily_completion.sql	(revision 42da64dc0d28f9380336816f6fb82c7572d0021d)
+++ db-scripts/triggers/compute_daily_completion.sql	(revision 42da64dc0d28f9380336816f6fb82c7572d0021d)
@@ -0,0 +1,84 @@
+-- Compute daily completion for a single user and date entirely in the DB
+-- Inserts a daily_completions row (if not exists), links finished tasks into task_daily_completions,
+-- and resets tasks.finished = false for that user.
+-- Usage: SELECT trekr.fn_compute_daily_completion(user_id := 123, day := DATE '2026-05-06');
+
+CREATE OR REPLACE FUNCTION trekr.fn_compute_daily_completion(user_id bigint, day date)
+RETURNS TABLE(created boolean, daily_completion_id bigint, procent numeric)
+LANGUAGE plpgsql
+AS $$
+DECLARE
+    total_count bigint;
+    finished_count bigint;
+    pct numeric;
+    dc_id bigint;
+    user_rec record;
+    finished_tasks RECORD;
+BEGIN
+    IF user_id IS NULL THEN
+        RAISE EXCEPTION 'user_id is required';
+    END IF;
+    IF day IS NULL THEN
+        RAISE EXCEPTION 'day is required';
+    END IF;
+    IF day > current_date THEN
+        RAISE EXCEPTION 'date cannot be in the future';
+    END IF;
+
+    -- ensure user tracking exists: rely on discipline_users table existence
+    IF NOT EXISTS (SELECT 1 FROM trekr.discipline_users du WHERE du.user_id = user_id) THEN
+        RAISE EXCEPTION 'Discipline tracking is not enabled for this user';
+    END IF;
+
+    -- if already computed for that user+date, return existing
+    SELECT dc.daily_completion_id, dc.procent INTO dc_id, pct
+    FROM trekr.daily_completions dc
+    WHERE dc.user_id = user_id AND dc.date = day
+    LIMIT 1;
+
+    IF dc_id IS NOT NULL THEN
+        RETURN QUERY SELECT false, dc_id, pct;
+        RETURN;
+    END IF;
+
+    SELECT COUNT(*) INTO total_count FROM trekr.tasks t WHERE t.discipline_user_id = (
+        SELECT du.discipline_user_id FROM trekr.discipline_users du WHERE du.user_id = user_id
+    );
+
+    SELECT COUNT(*) INTO finished_count FROM trekr.tasks t WHERE t.discipline_user_id = (
+        SELECT du.discipline_user_id FROM trekr.discipline_users du WHERE du.user_id = user_id
+    ) AND t.finished = true;
+
+    IF total_count <= 0 THEN
+        pct := 0;
+    ELSE
+        pct := round((finished_count::numeric * 100) / total_count::numeric, 2);
+    END IF;
+
+    -- insert daily completion
+    INSERT INTO trekr.daily_completions (user_id, date, procent)
+    VALUES (user_id, day, pct)
+    RETURNING daily_completion_id INTO dc_id;
+
+    -- link finished tasks
+    FOR finished_tasks IN
+        SELECT t.task_id FROM trekr.tasks t
+        WHERE t.discipline_user_id = (
+            SELECT du.discipline_user_id FROM trekr.discipline_users du WHERE du.user_id = user_id
+        ) AND t.finished = true
+    LOOP
+        INSERT INTO trekr.task_daily_completions (task_id, daily_completion_id)
+        VALUES (finished_tasks.task_id, dc_id)
+        ON CONFLICT DO NOTHING;
+    END LOOP;
+
+    -- reset all tasks for user
+    UPDATE trekr.tasks t SET finished = false
+    WHERE t.discipline_user_id = (
+        SELECT du.discipline_user_id FROM trekr.discipline_users du WHERE du.user_id = user_id
+    );
+
+    RETURN QUERY SELECT true, dc_id, pct;
+END;
+$$;
+