-- Create notifications table for in-app alerts
CREATE TABLE IF NOT EXISTS notifications (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    organization_id UUID NOT NULL,
    user_id UUID NOT NULL,
    title VARCHAR(255) NOT NULL,
    message TEXT NOT NULL,
    notification_type VARCHAR(50) DEFAULT 'info', -- 'info', 'warning', 'success', 'deadline'
    is_read BOOLEAN DEFAULT FALSE,
    link_url VARCHAR(255), -- Optional link to redirect the user
    created_at TIMESTAMP WITH TIME ZONE DEFAULT NOW()
);

CREATE INDEX IF NOT EXISTS idx_notifications_user_id ON notifications(user_id);
CREATE INDEX IF NOT EXISTS idx_notifications_org_id ON notifications(organization_id);
CREATE INDEX IF NOT EXISTS idx_notifications_unread ON notifications(user_id) WHERE is_read = FALSE;