biometric-wallet

;; Biometric Seedless Smart Wallet
;; Implements non-custodial wallet using secp256k1-verify (Clarity 4 compatible fallback)

;; Data Variables
(define-data-var owner-pubkey (buff 33) 0x00) ;; Compressed secp256k1 public key
(define-data-var nonce uint u0)
(define-data-var initialized bool false)

;; Error Constants
(define-constant ERR-INVALID-SIGNATURE (err u100))
(define-constant ERR-INVALID-NONCE (err u101))
(define-constant ERR-UNAUTHORIZED (err u102))
(define-constant ERR-ALREADY-INITIALIZED (err u103))
(define-constant ERR-NOT-INITIALIZED (err u104))

;; Initialization - can only be called once
(define-public (initialize (new-owner-pubkey (buff 33)))
    (begin
        (asserts! (not (var-get initialized)) ERR-ALREADY-INITIALIZED)
        (var-set owner-pubkey new-owner-pubkey)
        (var-set initialized true)
        (ok true)
    )
)

;; Read-only functions
(define-read-only (get-nonce)
    (ok (var-get nonce))
)

(define-read-only (get-owner-pubkey)
    (ok (var-get owner-pubkey))
)

(define-read-only (is-initialized)
    (ok (var-get initialized))
)

(define-read-only (verify-signature
        (hash (buff 32))
        (signature (buff 65))
    )
    (secp256k1-verify hash signature (var-get owner-pubkey))
)

;; Public functions
(define-public (execute-action
        (action-payload (buff 128))
        (signature (buff 65))
    )
    (let (
            (current-nonce (var-get nonce))
            (message-hash (sha256 (unwrap-panic (to-consensus-buff? {
                payload: action-payload,
                nonce: current-nonce,
            }))))
        )
        ;; Ensure initialized
        (asserts! (var-get initialized) ERR-NOT-INITIALIZED)

        ;; Verify signature
        (asserts!
            (secp256k1-verify message-hash signature (var-get owner-pubkey))
            ERR-INVALID-SIGNATURE
        )

        ;; Increment nonce
        (var-set nonce (+ current-nonce u1))

        ;; Execute action (placeholder for custom logic)

        (ok "Action executed successfully")
    )
)