Implement XCallManager

[CyrusVorwald]

Overview

The XCallManager contract manages cross-chain protocols, whitelists actions, and handles cross-chain calls.

(define-trait xcall-manager-trait
  (
    ;; Only callable once, sets up the initial state of the contract
    (initialize 
      (principal principal (string-ascii 64) principal 
       (list 100 (string-ascii 64)) (list 100 (string-ascii 64)))
      (response bool uint)
    )

    ;; Set a new admin address
    ;; Can only be called by the current admin
    ;; The new admin must accept the role separately
    (set-admin (principal) (response bool uint))

    ;; Accept the admin role
    ;; Must be called by the address set as the new admin
    (accept-admin-role () (response bool uint))

    ;; Update the list of approved source and destination protocols
    ;; Can only be called by the admin or through a whitelisted cross-chain message
    (set-protocols 
      ((list 100 (string-ascii 64)) (list 100 (string-ascii 64))) 
      (response bool uint)
    )

    ;; Propose the removal of a specific protocol
    ;; Can only be called by the admin
    ;; Allows for a grace period before removal takes effect
    (propose-removal ((string-ascii 64)) (response bool uint))

    ;; Add an action to the whitelist
    ;; Can only be called by the admin
    ;; Whitelisted actions are allowed to be executed when received as cross-chain messages
    (whitelist-action ((buff 1024)) (response bool uint))

    ;; Remove an action from the whitelist
    ;; Can only be called by the admin
    ;; Prevents a previously approved action from being executed
    (remove-action ((buff 1024)) (response bool uint))

    ;; Process an incoming cross-chain message
    ;; Can only be called by the xCall service
    ;; Verifies the message source, protocols, and executes whitelisted actions
    (handle-call-message 
      ((string-ascii 64) (buff 1024) (list 100 (string-ascii 64)))
      (response bool uint)
    )

    ;; Retrieve the current list of approved protocols
    ;; Read-only function, can be called by anyone
    (get-protocols () 
      (response 
        (tuple 
          (sources (list 100 (string-ascii 64))) 
          (destinations (list 100 (string-ascii 64)))
        ) 
        uint
      )
    )

    ;; Check if a given list of protocols matches the approved list
    ;; Read-only function, used to validate protocol usage
    (verify-protocols ((list 100 (string-ascii 64))) (response bool uint))

    ;; Check if a specific action is currently whitelisted
    ;; Read-only function, can be used to verify action status before sending cross-chain
    (is-action-whitelisted ((buff 1024)) (response bool uint))

    ;; Get the current admin address
    ;; Read-only function, provides transparency on who controls admin functions
    (get-admin () (response principal uint))

    ;; Get the address of the xCall service contract
    ;; Read-only function, allows verification of the authorized caller for handle-call-message
    (get-x-call () (response principal uint))
  )
)