-- 243_support_tickets.sql
-- 轻量工单系统：用户提交问题，管理员回复，任一方可关闭。
CREATE TABLE IF NOT EXISTS support_tickets (
    id BIGSERIAL PRIMARY KEY,
    user_id BIGINT NOT NULL,
    subject VARCHAR(200) NOT NULL,
    status VARCHAR(16) NOT NULL DEFAULT 'open',
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    closed_at TIMESTAMPTZ
);

CREATE TABLE IF NOT EXISTS support_ticket_replies (
    id BIGSERIAL PRIMARY KEY,
    ticket_id BIGINT NOT NULL REFERENCES support_tickets(id) ON DELETE CASCADE,
    author_type VARCHAR(8) NOT NULL,
    author_id BIGINT NOT NULL DEFAULT 0,
    body TEXT NOT NULL,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);

CREATE INDEX IF NOT EXISTS idx_support_tickets_user_status ON support_tickets(user_id, status);
CREATE INDEX IF NOT EXISTS idx_support_tickets_status ON support_tickets(status);
CREATE INDEX IF NOT EXISTS idx_support_ticket_replies_ticket ON support_ticket_replies(ticket_id);