-- ============================================================================
-- Schema: trading
-- Table: price_alerts
-- Description: Alertas de precio configuradas por usuarios para el módulo de trading
-- Dependencies: trading.alert_type, trading.alert_status, auth.users, trading.symbols
-- Created: 2026-02-03
-- Updated: 2026-02-04
-- ============================================================================

CREATE TABLE trading.price_alerts (
  -- Primary Key
  id UUID PRIMARY KEY DEFAULT gen_random_uuid(),

  -- Relaciones
  user_id UUID NOT NULL REFERENCES auth.users(id) ON DELETE CASCADE,
  symbol_id UUID NOT NULL REFERENCES trading.symbols(id) ON DELETE CASCADE,

  -- Configuración de alerta
  alert_type trading.alert_type NOT NULL,
  target_price DECIMAL(18,8),
  percent_threshold DECIMAL(5,2),

  -- Estado
  status trading.alert_status NOT NULL DEFAULT 'active',

  -- Ejecución
  triggered_at TIMESTAMPTZ,
  triggered_price DECIMAL(18,8),

  -- Expiración
  expires_at TIMESTAMPTZ,

  -- Notificación
  notification_channels TEXT[] DEFAULT ARRAY['push', 'email'],

  -- Mensaje personalizado
  message TEXT,

  -- Timestamps
  created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
  updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),

  -- Constraints
  CONSTRAINT chk_target_price_positive CHECK (target_price IS NULL OR target_price > 0),
  CONSTRAINT chk_percent_threshold_valid CHECK (percent_threshold IS NULL OR (percent_threshold > 0 AND percent_threshold <= 100)),
  CONSTRAINT chk_alert_config CHECK (
    (alert_type IN ('price_above', 'price_below') AND target_price IS NOT NULL) OR
    (alert_type = 'percent_change' AND percent_threshold IS NOT NULL) OR
    (alert_type = 'volume_spike')
  )
);

-- Índices para performance
CREATE INDEX idx_price_alerts_user ON trading.price_alerts(user_id);
CREATE INDEX idx_price_alerts_symbol ON trading.price_alerts(symbol_id);
CREATE INDEX idx_price_alerts_active ON trading.price_alerts(status) WHERE status = 'active';
CREATE INDEX idx_price_alerts_expiry ON trading.price_alerts(expires_at)
  WHERE expires_at IS NOT NULL AND status = 'active';

-- Trigger para actualizar updated_at
CREATE OR REPLACE FUNCTION trading.update_price_alerts_timestamp()
RETURNS TRIGGER AS $$
BEGIN
  NEW.updated_at = NOW();
  RETURN NEW;
END;
$$ LANGUAGE plpgsql;

CREATE TRIGGER trg_price_alerts_updated_at
  BEFORE UPDATE ON trading.price_alerts
  FOR EACH ROW
  EXECUTE FUNCTION trading.update_price_alerts_timestamp();

-- Comentarios
COMMENT ON TABLE trading.price_alerts IS 'Alertas de precio configuradas por usuarios para el módulo de trading';
COMMENT ON COLUMN trading.price_alerts.id IS 'Identificador único de la alerta';
COMMENT ON COLUMN trading.price_alerts.user_id IS 'Referencia al usuario (auth.users)';
COMMENT ON COLUMN trading.price_alerts.symbol_id IS 'Referencia al símbolo de trading';
COMMENT ON COLUMN trading.price_alerts.alert_type IS 'Tipo de alerta: price_above, price_below, percent_change, volume_spike';
COMMENT ON COLUMN trading.price_alerts.target_price IS 'Precio objetivo para alertas de precio (price_above/price_below)';
COMMENT ON COLUMN trading.price_alerts.percent_threshold IS 'Umbral porcentual para alertas de cambio porcentual';
COMMENT ON COLUMN trading.price_alerts.status IS 'Estado de la alerta: active, triggered, expired, cancelled';
COMMENT ON COLUMN trading.price_alerts.triggered_at IS 'Timestamp cuando se disparó la alerta';
COMMENT ON COLUMN trading.price_alerts.triggered_price IS 'Precio al momento de dispararse la alerta';
COMMENT ON COLUMN trading.price_alerts.expires_at IS 'Fecha de expiración opcional de la alerta';
COMMENT ON COLUMN trading.price_alerts.notification_channels IS 'Canales de notificación: push, email, sms, etc.';
COMMENT ON COLUMN trading.price_alerts.message IS 'Mensaje personalizado para la alerta';
COMMENT ON COLUMN trading.price_alerts.created_at IS 'Timestamp de creación';
COMMENT ON COLUMN trading.price_alerts.updated_at IS 'Timestamp de última actualización';