-- Reporting and dashboards — spec section 14.
--
-- Every view is declared WITH (security_invoker = true). Without it a view runs
-- with the privileges of its owner and would hand any authenticated caller the
-- whole table, quietly defeating the row-level security the rest of this build
-- depends on. With it, a teacher querying v_student_directory sees exactly the
-- students their own policies allow.

-- ============================================================================
-- STUDENTS
-- ============================================================================

CREATE OR REPLACE VIEW public.v_student_directory
WITH (security_invoker = true) AS
SELECT
  s.id AS student_id,
  s.first_name,
  s.middle_name,
  s.last_name,
  s.preferred_name,
  s.dob,
  s.grade_level,
  s.enrollment_status,
  s.attendance_basis,
  s.calendar_basis,
  s.is_support_student,
  c.id   AS primary_campus_id,
  c.name AS primary_campus,
  t.name AS tuition_tier,
  hs.household_id,
  h.name AS household_name,
  -- Campuses beyond the primary one, for the multi-campus case.
  (SELECT array_agg(DISTINCT cc.name)
     FROM public.student_campus_schedules sc
     JOIN public.campuses cc ON cc.id = sc.campus_id
    WHERE sc.student_id = s.id
      AND (sc.effective_end IS NULL OR sc.effective_end >= CURRENT_DATE)
  ) AS scheduled_campuses,
  (SELECT COALESCE(SUM(sc.scheduled_days_per_week), 0)
     FROM public.student_campus_schedules sc
    WHERE sc.student_id = s.id
      AND sc.effective_start <= CURRENT_DATE
      AND (sc.effective_end IS NULL OR sc.effective_end >= CURRENT_DATE)
  ) AS scheduled_days_per_week,
  (SELECT COUNT(*) FROM public.student_alerts a
    WHERE a.student_id = s.id AND a.is_active
      AND a.effective_date <= CURRENT_DATE
      AND (a.expiration_date IS NULL OR a.expiration_date >= CURRENT_DATE)
  ) AS active_alert_count
FROM public.students s
LEFT JOIN public.campuses c ON c.id = s.primary_campus_id
LEFT JOIN public.tuition_tiers t ON t.id = s.tuition_tier_id
LEFT JOIN public.household_students hs
       ON hs.student_id = s.id AND hs.is_primary_household
LEFT JOIN public.households h ON h.id = hs.household_id;

GRANT SELECT ON public.v_student_directory TO authenticated;

-- ============================================================================
-- BILLING
-- ============================================================================

CREATE OR REPLACE VIEW public.v_outstanding_invoices
WITH (security_invoker = true) AS
SELECT
  i.id AS invoice_id,
  i.invoice_number,
  i.student_id,
  s.first_name || ' ' || s.last_name AS student_name,
  i.household_id,
  i.campus_id,
  c.name AS campus_name,
  i.billing_period_start,
  i.billing_period_end,
  i.invoice_date,
  i.due_date,
  i.total_cents,
  i.amount_paid_cents,
  i.balance_due_cents,
  i.status,
  CURRENT_DATE - i.due_date AS days_overdue
FROM public.invoices i
JOIN public.students s ON s.id = i.student_id
LEFT JOIN public.campuses c ON c.id = i.campus_id
WHERE i.status IN ('issued','partially_paid')
  AND i.balance_due_cents > 0;

GRANT SELECT ON public.v_outstanding_invoices TO authenticated;

-- Combined household position — the spec's "combined household account".
CREATE OR REPLACE VIEW public.v_household_balances
WITH (security_invoker = true) AS
SELECT
  h.id AS household_id,
  h.name AS household_name,
  COUNT(DISTINCT hs.student_id) AS student_count,
  COALESCE(SUM(i.total_cents), 0)       AS invoiced_cents,
  COALESCE(SUM(i.amount_paid_cents), 0) AS paid_cents,
  COALESCE(SUM(i.balance_due_cents) FILTER (
    WHERE i.status IN ('issued','partially_paid')), 0) AS balance_due_cents
FROM public.households h
LEFT JOIN public.household_students hs ON hs.household_id = h.id
LEFT JOIN public.invoices i ON i.household_id = h.id AND i.status <> 'void'
GROUP BY h.id, h.name;

GRANT SELECT ON public.v_household_balances TO authenticated;

-- ============================================================================
-- CAMPUS + ATTENDANCE
-- ============================================================================

CREATE OR REPLACE VIEW public.v_campus_enrollment
WITH (security_invoker = true) AS
SELECT
  c.id AS campus_id,
  c.name AS campus_name,
  c.is_active,
  c.student_capacity,
  COUNT(DISTINCT s.id) FILTER (WHERE s.enrollment_status = 'enrolled') AS enrolled_count,
  COUNT(DISTINCT s.id) FILTER (
    WHERE s.enrollment_status = 'enrolled' AND s.attendance_basis = 'full_time') AS full_time_count,
  COUNT(DISTINCT s.id) FILTER (
    WHERE s.enrollment_status = 'enrolled' AND s.attendance_basis = 'part_time') AS part_time_count,
  COUNT(DISTINCT s.id) FILTER (
    WHERE s.enrollment_status = 'enrolled' AND s.is_support_student) AS support_count,
  CASE WHEN c.student_capacity IS NULL OR c.student_capacity = 0 THEN NULL
       ELSE ROUND(COUNT(DISTINCT s.id) FILTER (WHERE s.enrollment_status = 'enrolled')::numeric
                  * 100.0 / c.student_capacity, 1)
  END AS capacity_used_percent
FROM public.campuses c
LEFT JOIN public.students s ON s.primary_campus_id = c.id
GROUP BY c.id, c.name, c.is_active, c.student_capacity;

GRANT SELECT ON public.v_campus_enrollment TO authenticated;

CREATE OR REPLACE VIEW public.v_attendance_summary
WITH (security_invoker = true) AS
SELECT
  a.student_id,
  s.first_name || ' ' || s.last_name AS student_name,
  s.primary_campus_id,
  date_trunc('month', a.date)::date AS month,
  COUNT(*)                                        AS recorded_days,
  COUNT(*) FILTER (WHERE a.status = 'present')    AS present_days,
  COUNT(*) FILTER (WHERE a.status = 'absent')     AS absent_days,
  COUNT(*) FILTER (WHERE a.status = 'late')       AS late_days,
  COUNT(*) FILTER (WHERE a.status = 'excused')    AS excused_days,
  ROUND(COUNT(*) FILTER (WHERE a.status IN ('present','late'))::numeric
        * 100.0 / NULLIF(COUNT(*), 0), 1)         AS attendance_rate_percent
FROM public.attendance a
JOIN public.students s ON s.id = a.student_id
GROUP BY a.student_id, s.first_name, s.last_name, s.primary_campus_id, date_trunc('month', a.date);

GRANT SELECT ON public.v_attendance_summary TO authenticated;

-- ============================================================================
-- COMPLIANCE + MANAGEMENT
-- ============================================================================

CREATE OR REPLACE VIEW public.v_certification_expiry
WITH (security_invoker = true) AS
SELECT
  sc.id AS certification_id,
  sc.user_id,
  p.full_name AS staff_name,
  ct.name AS certification_name,
  sc.issued_on,
  sc.expires_on,
  sc.status,
  sc.expires_on - CURRENT_DATE AS days_until_expiry,
  CASE
    WHEN sc.expires_on IS NULL THEN 'no_expiry'
    WHEN sc.expires_on < CURRENT_DATE THEN 'expired'
    WHEN sc.expires_on < CURRENT_DATE + make_interval(days => ct.renewal_reminder_days)
      THEN 'expiring_soon'
    ELSE 'current'
  END AS expiry_state
FROM public.staff_certifications sc
JOIN public.certification_types ct ON ct.id = sc.certification_type_id
LEFT JOIN public.profiles p ON p.id = sc.user_id
WHERE sc.status IN ('active','pending');

GRANT SELECT ON public.v_certification_expiry TO authenticated;

-- The management dashboard's task queue.
CREATE OR REPLACE VIEW public.v_open_tasks
WITH (security_invoker = true) AS
SELECT
  t.id AS task_id,
  t.title,
  t.priority,
  t.status,
  t.due_date,
  t.campus_id,
  c.name AS campus_name,
  t.assigned_to,
  p.full_name AS assigned_to_name,
  t.related_student_id,
  CASE
    WHEN t.due_date IS NULL THEN 'no_due_date'
    WHEN t.due_date < CURRENT_DATE THEN 'overdue'
    WHEN t.due_date <= CURRENT_DATE + 7 THEN 'due_soon'
    ELSE 'scheduled'
  END AS due_state
FROM public.tasks t
LEFT JOIN public.campuses c ON c.id = t.campus_id
LEFT JOIN public.profiles p ON p.id = t.assigned_to
WHERE t.status IN ('open','in_progress','blocked');

GRANT SELECT ON public.v_open_tasks TO authenticated;

-- Per-student follow-ups still owed, from the notes system.
CREATE OR REPLACE VIEW public.v_pending_followups
WITH (security_invoker = true) AS
SELECT
  n.id AS note_id,
  n.student_id,
  s.first_name || ' ' || s.last_name AS student_name,
  nc.name AS category,
  n.title,
  n.follow_up_date,
  n.resolution_status,
  n.author_id,
  n.campus_id,
  CURRENT_DATE - n.follow_up_date AS days_overdue
FROM public.student_notes n
JOIN public.students s ON s.id = n.student_id
JOIN public.note_categories nc ON nc.id = n.category_id
WHERE n.follow_up_date IS NOT NULL
  AND n.resolution_status IN ('open','in_progress');

GRANT SELECT ON public.v_pending_followups TO authenticated;