-- +goose Up

ALTER TABLE users
  ADD COLUMN invite_code VARCHAR(32) NULL COMMENT '用户专属邀请码' AFTER register_track_code,
  ADD COLUMN invited_by_id BIGINT UNSIGNED NOT NULL DEFAULT 0 COMMENT '邀请人用户ID' AFTER invite_code,
  ADD COLUMN invite_verified_at DATETIME NULL COMMENT '被邀请人生效实名时间' AFTER invited_by_id,
  ADD UNIQUE KEY uk_users_invite_code (invite_code),
  ADD KEY idx_users_invited_by_id (invited_by_id);

CREATE TABLE user_invitations (
  id BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
  inviter_id BIGINT UNSIGNED NOT NULL COMMENT '邀请人用户ID',
  invitee_id BIGINT UNSIGNED NOT NULL COMMENT '被邀请人用户ID',
  distribution_site_id BIGINT UNSIGNED NOT NULL DEFAULT 0 COMMENT '所属分销站点ID (0=主站)',
  invite_code VARCHAR(32) NOT NULL DEFAULT '' COMMENT '当时使用的邀请码',
  status VARCHAR(32) NOT NULL DEFAULT 'pending' COMMENT '状态: pending=注册待实名, active=已实名生效, invalid=已失效',
  verified_at DATETIME NULL COMMENT '被邀请人实名通过时间(首月计时起点)',
  created_at DATETIME NOT NULL,
  updated_at DATETIME NOT NULL,
  PRIMARY KEY (id),
  UNIQUE KEY uk_user_invitations_invitee (invitee_id),
  KEY idx_user_invitations_inviter (inviter_id, status)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT='用户邀请关系表';

CREATE TABLE invitation_rebate_configs (
  id BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
  distribution_site_id BIGINT UNSIGNED NOT NULL DEFAULT 0 COMMENT '所属分销站点ID (0=主站全局默认)',
  first_month_rate DECIMAL(6,4) NOT NULL DEFAULT 0.6000 COMMENT '首月返利比例 (默认0.60)',
  second_month_rate DECIMAL(6,4) NOT NULL DEFAULT 0.3000 COMMENT '次月返利比例 (默认0.30)',
  subsequent_rate DECIMAL(6,4) NOT NULL DEFAULT 0.1500 COMMENT '往后返利比例 (默认0.15)',
  enabled TINYINT(1) NOT NULL DEFAULT 1 COMMENT '是否启用返利',
  created_at DATETIME NOT NULL,
  updated_at DATETIME NOT NULL,
  PRIMARY KEY (id),
  UNIQUE KEY uk_invitation_rebate_configs_site (distribution_site_id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT='邀请返利比例配置表';

INSERT INTO invitation_rebate_configs (distribution_site_id, first_month_rate, second_month_rate, subsequent_rate, enabled, created_at, updated_at)
VALUES (0, 0.6000, 0.3000, 0.1500, 1, NOW(), NOW())
ON DUPLICATE KEY UPDATE updated_at = NOW();

CREATE TABLE invitation_rebate_ledgers (
  id BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
  order_id BIGINT UNSIGNED NOT NULL COMMENT '关联订单ID',
  order_no VARCHAR(64) NOT NULL COMMENT '订单号',
  distribution_site_id BIGINT UNSIGNED NOT NULL DEFAULT 0 COMMENT '分担成本的站点ID (0=主站)',
  inviter_id BIGINT UNSIGNED NOT NULL COMMENT '获得返利的用户ID',
  invitee_id BIGINT UNSIGNED NOT NULL COMMENT '贡献交易的被邀请人ID',
  trade_role VARCHAR(16) NOT NULL COMMENT '交易端角色: buyer=买家, seller=卖家',
  order_profit_basis_cent BIGINT NOT NULL DEFAULT 0 COMMENT '订单收益基数(分)',
  single_side_basis_cent BIGINT NOT NULL DEFAULT 0 COMMENT '单边收益基数(分)',
  rate_applied DECIMAL(6,4) NOT NULL DEFAULT 0 COMMENT '计算时采用的返利比例',
  days_since_verified INT NOT NULL DEFAULT 0 COMMENT '被邀请人实名至成交的天数',
  cycle_stage VARCHAR(32) NOT NULL DEFAULT '' COMMENT '周期阶段: first_month/second_month/subsequent',
  rebate_amount_cent BIGINT NOT NULL DEFAULT 0 COMMENT '实际返利金额(分)',
  wallet_ledger_no VARCHAR(64) NOT NULL DEFAULT '' COMMENT '关联钱包流水号',
  status VARCHAR(32) NOT NULL DEFAULT 'settled' COMMENT '状态: settled=已发放, cancelled=已取消/冲正',
  settled_at DATETIME NOT NULL COMMENT '结算发放时间',
  created_at DATETIME NOT NULL,
  updated_at DATETIME NOT NULL,
  PRIMARY KEY (id),
  UNIQUE KEY uk_invitation_rebate_order_role (order_id, trade_role),
  KEY idx_invitation_rebate_inviter (inviter_id, settled_at),
  KEY idx_invitation_rebate_site (distribution_site_id, settled_at)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT='邀请返利结算明细表';

-- +goose Down

DROP TABLE IF EXISTS invitation_rebate_ledgers;
DROP TABLE IF EXISTS invitation_rebate_configs;
DROP TABLE IF EXISTS user_invitations;

ALTER TABLE users
  DROP COLUMN invite_verified_at,
  DROP COLUMN invited_by_id,
  DROP COLUMN invite_code;