// Assume contract instance A is applying for contract instance B...
module NaiveDAC{
  function initDAC(req){
  	// public keys of contract instances that a contract instance has accepted
  	// public key -> DOI | remark
    Global.acceptList = {
    };
    // public keys of contract instances that a contract instance is being applied for
    // public key -> DOI | remark
    Global.appliedList = {
    };
    // DOIs of contract instances that a contract instance is applying for
    // DOI -> remark
    Global.applyingDOIList = {
    };
    // Public key of the owner of a contract instance
    Global.owner = req;
  }
  // B accepts one application from public key "req"
  export function accept(req){
    if (requester == Global.owner){
      Global.acceptList[req] = Global.appliedList[req];
      if (Global.appliedList[req] != undefined){
        Global.appliedList[req] = undefined;
       }
      return true;
    }
    return false;
  }
  // B cancels one application from public key "req"
  export function cancel(req){
    if (requester == Global.owner){
      Global.appliedList[req] = Global.acceptList[req];
      if (Global.acceptList[req] != undefined){
        Global.acceptList[req] = undefined;
       }
      return true;
    }
    return false;
  }
  // B is being applied for "remark" reason by a public "requester" and "requesterDOI"
  export function applied(remark){
    if (remark != undefined && requester != undefined && requesterDOI != undefined){
      Global.appliedList[requester] = requesterDOI + "|" + remark;
      return "success";
    }
    return "failed";
  }
  // A is applying for "targetDOI" for "remark" reason
  export function applying(args){
    args = JSON.parse(args);
    if (args.remark != undefined && args.targetDOI != undefined){
      Global.applyingDOIList[args.targetDOI] = args.remark;
      return executeContractByDOI(args.targetDOI, "applied", args.remark);
    }
    return "failed";
  }
  export function loadResource(arg){
    return Global.Resources.loadAsString(arg);
  }
  export function isOwner(arg){
    return Global.owner==requester;
  }
  export function getAppliedList(arg){
    return JSON.stringify(Global.appliedList);
  }
  export function getAcceptList(arg){
    return JSON.stringify(Global.acceptList);
  }
  export function getApplyingDOIList(arg){
    return JSON.stringify(Global.applyingDOIList);
  }
  // check if public "requester" has the permission of B
  export function appliedHasPermission(arg){
    return (Global.acceptList[requester]!=undefined);
  }
  // check if "req" has the permission of B
  export function checkPermission(req){
    return (Global.acceptList[req]!=undefined);
  }
  // check if A with "pubkey" has the permission of B with "targetDOI"
  export function applyingHasPermission(targetDOI){
    return executeContractByDOI(targetDOI, "appliedHasPermission");
  }
}