staking

;; Staking Contract
;; Allows users to stake STX

;; Constants
(define-constant contract-owner tx-sender)
(define-constant err-owner-only (err u100))
(define-constant err-insufficient-balance (err u101))
(define-constant err-no-stake (err u102))

;; Data Variables
(define-data-var total-staked uint u0)

;; Data Maps
(define-map stakes principal uint)
(define-map stake-time principal uint)

;; Read-only functions
(define-read-only (get-stake (user principal))
  (default-to u0 (map-get? stakes user))
)

(define-read-only (get-total-staked)
  (var-get total-staked)
)

;; Public functions
(define-public (stake (amount uint))
  (begin
    (try! (stx-transfer? amount tx-sender (as-contract tx-sender)))
    (map-set stakes tx-sender (+ (get-stake tx-sender) amount))
    (map-set stake-time tx-sender burn-block-height)
    (var-set total-staked (+ (var-get total-staked) amount))
    (ok true)
  )
)

(define-public (unstake (amount uint))
  (let ((current-stake (get-stake tx-sender)))
    (asserts! (>= current-stake amount) err-insufficient-balance)
    (try! (as-contract (stx-transfer? amount tx-sender contract-caller)))
    (map-set stakes tx-sender (- current-stake amount))
    (var-set total-staked (- (var-get total-staked) amount))
    (ok true)
  )
)