-- Backfilled primary leases use the same 90s TTL as
-- server/internal/tenant/app/desktop_presence.go:desktopClientPresenceTTL.
-- Keep these values aligned; desktop heartbeat interval must be < TTL/2 so
-- a single missed heartbeat does not let another client steal primary.
CREATE TABLE IF NOT EXISTS desktop_client_primary_leases (
    tenant_id BIGINT NOT NULL REFERENCES tenants(id) ON DELETE CASCADE,
    workspace_id BIGINT NOT NULL REFERENCES workspaces(id) ON DELETE CASCADE,
    primary_client_id UUID NOT NULL REFERENCES desktop_clients(id) ON DELETE CASCADE,
    lease_expires_at TIMESTAMPTZ NOT NULL,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    PRIMARY KEY (tenant_id, workspace_id)
);

CREATE INDEX IF NOT EXISTS idx_desktop_client_primary_leases_primary_client
    ON desktop_client_primary_leases (primary_client_id);

CREATE INDEX IF NOT EXISTS idx_desktop_clients_tenant_workspace_seen_active
    ON desktop_clients (tenant_id, workspace_id, last_seen_at DESC, created_at DESC, id DESC)
    WHERE revoked_at IS NULL;

CREATE INDEX IF NOT EXISTS idx_desktop_clients_tenant_workspace_user_seen_active
    ON desktop_clients (tenant_id, workspace_id, user_id, last_seen_at DESC, created_at DESC, id DESC)
    WHERE revoked_at IS NULL;

INSERT INTO desktop_client_primary_leases (
    tenant_id,
    workspace_id,
    primary_client_id,
    lease_expires_at
)
SELECT
    tenant_id,
    workspace_id,
    id,
    COALESCE(last_seen_at, created_at) + INTERVAL '90 seconds'
FROM (
    SELECT
        dc.id,
        dc.tenant_id,
        dc.workspace_id,
        dc.created_at,
        dc.last_seen_at,
        ROW_NUMBER() OVER (
            PARTITION BY dc.tenant_id, dc.workspace_id
            ORDER BY dc.last_seen_at DESC NULLS LAST, dc.created_at DESC, dc.id DESC
        ) AS rn
    FROM desktop_clients dc
    WHERE dc.revoked_at IS NULL
) ranked_clients
WHERE rn = 1
ON CONFLICT (tenant_id, workspace_id) DO NOTHING;