-- 018: Trade settlements (clearing-service)
CREATE TABLE IF NOT EXISTS settlements (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    trade_id UUID NOT NULL REFERENCES trades(id),
    buyer_id UUID NOT NULL REFERENCES users(id),
    seller_id UUID NOT NULL REFERENCES users(id),
    amount NUMERIC(12,2) NOT NULL,
    buyer_fee NUMERIC(12,4) NOT NULL DEFAULT 0,
    seller_fee NUMERIC(12,4) NOT NULL DEFAULT 0,
    status VARCHAR(20) NOT NULL DEFAULT 'pending' CHECK (status IN ('pending', 'completed', 'failed', 'reversed')),
    tx_hash VARCHAR(66),
    completed_at TIMESTAMPTZ,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);

CREATE INDEX idx_settlements_trade_id ON settlements(trade_id);
CREATE INDEX idx_settlements_status ON settlements(status);