-- VC Gateway Schema
-- Invite links, visitor sessions, and DM support for anonymous visitors.
-- Part of Sprinter Hub - supports fundraising / investor access.

-- Invite links with expiration and channel scoping
CREATE TABLE IF NOT EXISTS Hub_InviteLinks (
    ID              INT UNSIGNED AUTO_INCREMENT PRIMARY KEY,
    Token           VARCHAR(64) NOT NULL COMMENT 'URL-safe token for link',
    Label           VARCHAR(255) NOT NULL DEFAULT '' COMMENT 'Human label e.g. investor name',
    AllowedChannels JSON NOT NULL COMMENT 'Array of Hub_Channels.ID the visitor can read',
    HostAddress     VARCHAR(150) NOT NULL COMMENT 'Sprinter agent address of the host (DM target)',
    ExpiresAt       DATETIME NULL COMMENT 'NULL = never expires',
    MaxUses         INT UNSIGNED NOT NULL DEFAULT 0 COMMENT '0 = unlimited',
    UseCount        INT UNSIGNED NOT NULL DEFAULT 0,
    IsRevoked       TINYINT(1) NOT NULL DEFAULT 0,
    CreatedBy       VARCHAR(150) NOT NULL COMMENT 'Agent who created the link',
    CreatedAt       DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
    UpdatedAt       DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,

    UNIQUE KEY uq_invite_token (Token),
    INDEX idx_created_by (CreatedBy),
    INDEX idx_revoked (IsRevoked),
    INDEX idx_expires (ExpiresAt)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;

-- Visitor sessions - created when someone authenticates via invite link
CREATE TABLE IF NOT EXISTS Hub_Visitors (
    ID              INT UNSIGNED AUTO_INCREMENT PRIMARY KEY,
    InviteLinkID    INT UNSIGNED NOT NULL,
    VisitorToken    VARCHAR(64) NOT NULL COMMENT 'Session token for visitor API calls',
    DisplayName     VARCHAR(100) NOT NULL DEFAULT 'Visitor',
    DMChannelID     INT UNSIGNED NULL COMMENT 'Hub_Channels.ID for visitor<->host DM',
    CreatedAt       DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
    LastActiveAt    DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,

    UNIQUE KEY uq_visitor_token (VisitorToken),
    INDEX idx_invite_link (InviteLinkID),
    INDEX idx_dm_channel (DMChannelID),
    CONSTRAINT fk_visitor_invite FOREIGN KEY (InviteLinkID) REFERENCES Hub_InviteLinks(ID) ON DELETE CASCADE
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;

-- Rate limiting: track visitor message counts per sliding window
CREATE TABLE IF NOT EXISTS Hub_VisitorRateLimit (
    ID              INT UNSIGNED AUTO_INCREMENT PRIMARY KEY,
    VisitorID       INT UNSIGNED NOT NULL,
    WindowStart     DATETIME NOT NULL,
    MessageCount    INT UNSIGNED NOT NULL DEFAULT 1,

    UNIQUE KEY uq_visitor_window (VisitorID, WindowStart),
    CONSTRAINT fk_ratelimit_visitor FOREIGN KEY (VisitorID) REFERENCES Hub_Visitors(ID) ON DELETE CASCADE
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;