participant Patient
participant "Authorization Manager\n(in the hData DAS)" as AM
participant "Discovery Service\n(in the hData DAS)" as DS
participant "Primary Care Physician\n(primary hData system)" as PCP


note over Patient, PCP:
  Step 0: Registration w/ AM
end note

Patient -> AM: Register new account

note over AM: 
  hData DAS must guarantee
  HIPAA, HITECH compliant 
  authentication
end note

AM -> Patient: Confirmation



note over Patient, PCP:
  Step 1: First Contact hData Registration
end note

note over Patient, PCP: 
   Step 1a: Authorize PCP
   Note that more details of this step are discussed in the Kantara UMA protocol itself. 
end note
Patient -> PCP: Provide URL to patient-specific endpoint within AM

PCP -> AM: Register as healthcare provider of Patient

AM -> Patient: Authorize PCP hData System?
note over Patient: 
  Authorization can be done via
different means: 
  (i) Interactively by Patient
  (ii) Using pre-configured policy at DAS
  (iii) Providing signed authZ token
end note

Patient -> AM: Registration permission granted

AM->PCP: Notify authZ granted

note over Patient, PCP: 
  Step 1b: PCP Accesses Discovery Service
end note

PCP -> DS: Request provider list

DS -> PCP: Redirect to Access Manager

PCP -> AM: Request Access token for discovery

AM -> PCP: Grant Access Token (AT)


loop Access Patient-Specific Provider List
    PCP->DS: Seek provider list (AT)
    DS->AM: Validate AT
    note over AM:
       Validation can be either online
       or through signed tokens 
    end note
    AM-> DS: Confirm validation
    DS->PCP: Patient provider list
end

participant Patient
participant "Authorization Manager\n(hData DAS)" as AM
participant "Discovery Service\n(hData DAS)" as DS
participant "Primary Care Physician\n(primary hData system)" as PCP
participant "Emergency Room\n(3rd party hData system)" as ER

note over Patient, AM, PCP, ER:
  Step 2: Third party Access
end note


note over Patient, ER: 
  The emergency room hData system and the hData DAS are introduced to eachother as outlined in Step 1 (both 1a and 1b). At the end
of the introduction, the ER system has a list of hData provider systems for the Patient, including the PCP. The ER system selects the PCP
for the following workflow. The scenario begins with the ER requesting data from the PCP.
end note

ER -> PCP: Get Patient data

PCP -> ER: Redirect to AM

ER -> AM: Request access to PCP records
AM --> Patient: Authorize access to hData record

note over Patient: 
  Authorization can be done through 
  different means: 
  (i) Interactively by Patient
  (ii) Via pre-configured policy at DAS
end note

Patient --> AM: Permission granted

AM->ER: Access Token (AT)

ER ->PCP: Get Patient data (AT)

PCP->AM: Validate AT
note over AM:
   Validation can be either online
   or through signed tokens 
end note
AM->PCP: Token OK

PCP -> ER: Return data

ER -> ER: Upddate patient record

opt Poll for patient data at a later time
    ER ->PCP: Poll for new patient data (AT)
    
    PCP -> AM: Valiate AT
    note over AM:
       Validation can be either online
       or through signed tokens 
    end note

    alt Token OK
      AM -> PCP: Token OK
      PCP -> ER: Patient data update feed
    else Token expired
      AM -> PCP: Token expired
      PCP -> ER: Token expired\nredirect to AM
      ER -> AM: Request AT
      AM --> Patient: Authorize access to hData record

      note over Patient:  
  Authorization can be done through 
  different means: 
  (i) Interactively by Patient
  (ii) Via pre-configured policy at DAS
end note

      alt Authorization granted
      Patient --> AM: Provider permission granted

      AM->ER: Access Token (AT)
      ER ->PCP: Poll for new patient data (AT)
    
      PCP -> AM: Valiate AT

    
    note over AM:
       Validation can be either online
       or through signed tokens 
    end note

    AM->PCP: Token OK
    PCP -> ER: Patient data update feed

    else Authorization denied
      Patient --> AM: Provider permission denied
      AM -> ER: Unsuccessful AT response
    end
    end
end