-- V17: Enhanced Sharing System
-- Replaces simple share_links with comprehensive sharing capabilities

-- Enhanced shares table
CREATE TABLE shares (
    id TEXT PRIMARY KEY NOT NULL,
    target_type TEXT NOT NULL CHECK (target_type IN ('media', 'collection', 'tag', 'saved_search')),
    target_id TEXT NOT NULL,
    owner_id TEXT NOT NULL,
    recipient_type TEXT NOT NULL CHECK (recipient_type IN ('public_link', 'user', 'group', 'federated')),
    recipient_user_id TEXT,
    recipient_group_id TEXT,
    recipient_federated_handle TEXT,
    recipient_federated_server TEXT,
    public_token TEXT UNIQUE,
    public_password_hash TEXT,
    perm_view INTEGER NOT NULL DEFAULT 1,
    perm_download INTEGER NOT NULL DEFAULT 0,
    perm_edit INTEGER NOT NULL DEFAULT 0,
    perm_delete INTEGER NOT NULL DEFAULT 0,
    perm_reshare INTEGER NOT NULL DEFAULT 0,
    perm_add INTEGER NOT NULL DEFAULT 0,
    note TEXT,
    expires_at TEXT,
    access_count INTEGER NOT NULL DEFAULT 0,
    last_accessed TEXT,
    inherit_to_children INTEGER NOT NULL DEFAULT 1,
    parent_share_id TEXT,
    created_at TEXT NOT NULL,
    updated_at TEXT NOT NULL,
    FOREIGN KEY (owner_id) REFERENCES users(id) ON DELETE CASCADE,
    FOREIGN KEY (recipient_user_id) REFERENCES users(id) ON DELETE CASCADE,
    FOREIGN KEY (parent_share_id) REFERENCES shares(id) ON DELETE CASCADE,
    UNIQUE(owner_id, target_type, target_id, recipient_type, recipient_user_id)
);

CREATE INDEX idx_shares_owner ON shares(owner_id);
CREATE INDEX idx_shares_recipient_user ON shares(recipient_user_id);
CREATE INDEX idx_shares_target ON shares(target_type, target_id);
CREATE INDEX idx_shares_token ON shares(public_token);
CREATE INDEX idx_shares_expires ON shares(expires_at);

-- Share activity log
CREATE TABLE share_activity (
    id TEXT PRIMARY KEY NOT NULL,
    share_id TEXT NOT NULL,
    actor_id TEXT,
    actor_ip TEXT,
    action TEXT NOT NULL,
    details TEXT,
    timestamp TEXT NOT NULL,
    FOREIGN KEY (share_id) REFERENCES shares(id) ON DELETE CASCADE,
    FOREIGN KEY (actor_id) REFERENCES users(id) ON DELETE SET NULL
);

CREATE INDEX idx_share_activity_share ON share_activity(share_id);
CREATE INDEX idx_share_activity_timestamp ON share_activity(timestamp);

-- Share notifications
CREATE TABLE share_notifications (
    id TEXT PRIMARY KEY NOT NULL,
    user_id TEXT NOT NULL,
    share_id TEXT NOT NULL,
    notification_type TEXT NOT NULL,
    is_read INTEGER NOT NULL DEFAULT 0,
    created_at TEXT NOT NULL,
    FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE,
    FOREIGN KEY (share_id) REFERENCES shares(id) ON DELETE CASCADE
);

CREATE INDEX idx_share_notifications_user ON share_notifications(user_id);
CREATE INDEX idx_share_notifications_unread ON share_notifications(user_id, is_read) WHERE is_read = 0;

-- Migrate existing share_links to new shares table (if share_links exists)
INSERT OR IGNORE INTO shares (
    id, target_type, target_id, owner_id, recipient_type,
    public_token, public_password_hash, perm_view, perm_download,
    access_count, expires_at, created_at, updated_at
)
SELECT
    id, 'media', media_id, created_by, 'public_link',
    token, password_hash, 1, 1,
    view_count, expires_at, created_at, created_at
FROM share_links
WHERE EXISTS (SELECT 1 FROM sqlite_master WHERE type='table' AND name='share_links');