-- Add price and currency to courses table in LMS
ALTER TABLE courses ADD COLUMN IF NOT EXISTS price DOUBLE PRECISION DEFAULT 0.0;
ALTER TABLE courses ADD COLUMN IF NOT EXISTS currency VARCHAR(10) DEFAULT 'USD';

-- Create general trigger function if not exists
CREATE OR REPLACE FUNCTION trigger_set_timestamp()
RETURNS TRIGGER AS $$
BEGIN
  NEW.updated_at = NOW();
  RETURN NEW;
END;
$$ LANGUAGE plpgsql;

-- Create transactions table
CREATE TABLE transactions (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    organization_id UUID NOT NULL REFERENCES organizations(id),
    user_id UUID NOT NULL REFERENCES users(id),
    course_id UUID NOT NULL REFERENCES courses(id),
    amount DOUBLE PRECISION NOT NULL,
    currency VARCHAR(10) NOT NULL,
    status TEXT NOT NULL DEFAULT 'pending', -- 'pending', 'success', 'failure'
    provider_reference TEXT,
    created_at TIMESTAMP WITH TIME ZONE DEFAULT NOW(),
    updated_at TIMESTAMP WITH TIME ZONE DEFAULT NOW()
);

-- Trigger for updated_at in transactions
CREATE TRIGGER set_timestamp_transactions
BEFORE UPDATE ON transactions
FOR EACH ROW
EXECUTE PROCEDURE trigger_set_timestamp();