;; eid-card -- digital Eid greeting card exchange
(define-data-var card-count uint u0)
(define-map cards uint { sender: principal, receiver: principal, message: (string-ascii 100), eid: (string-ascii 10), block: uint })
(define-public (send-card (receiver principal) (message (string-ascii 100)) (eid (string-ascii 10)))
(let ((id (+ (var-get card-count) u1)))
(var-set card-count id)
(map-set cards id { sender: tx-sender, receiver: receiver, message: message, eid: eid, block: stacks-block-height }) (ok id)))
(define-read-only (get-card (id uint)) (map-get? cards id))
(define-read-only (get-count) (var-get card-count))