import orthanc
import csv
import json 
from datetime import date, datetime
from pathlib import Path

BASE_DIR = Path("/var/lib/orthanc")
ORTHANC_TRANSFERS_CSV_PATH = BASE_DIR / "transfers/transfers.csv"

##------------------------------
## AutoRoute Function
##------------------------------

def AutoRouteToModality(modality: str, resourceId: str) -> bool:
    isRouteSuccessful = False
    try:
        orthanc.RestApiPost(f"/modalities/{modality}/store", resourceId)
        # Create COMPLETED label
        orthanc.RestApiPut(f"/studies/{resourceId}/labels/--COMPLETED", "{}")
        isRouteSuccessful = True
    except: # Exceptions output to log files by default in Orthanc 
        # Create FAILED label
        orthanc.RestApiPut(f"/studies/{resourceId}/labels/--FAILED", "{}")
    finally: 
        # Delete PENDING label
        orthanc.RestApiDelete(f"/studies/{resourceId}/labels/--PENDING")
        return isRouteSuccessful


##------------------------------
## Onchange: Label and Autoroute
##------------------------------
 
##------------------------------
## Check for Stable Study updates and check DICOM metadata
##------------------------------ 
def OnChange(changeType: int, level: int, resourceId: str) -> None:
     if  changeType == orthanc.ChangeType.STABLE_STUDY:
        studyMetadata = json.loads(orthanc.RestApiGet(f"/studies/{resourceId}"))
        firstInstanceId = json.loads(orthanc.RestApiGet(f"/studies/{resourceId}/instances"))[0]['ID']
        firstInstanceMetadata = json.loads(orthanc.RestApiGet(f"/instances/{firstInstanceId}/metadata?expand"))   
    ##------------------------------
    ## Verbose Log Notification
    ##------------------------------
        orthanc.LogInfo(f"[STABLE STUDY RECEIVED] {studyMetadata}")
    ##------------------------------
    ## Recording DICOM metadata
    ##------------------------------
        ##------------------------------
        ## Required metadata
        ##------------------------------
        if firstInstanceMetadata['Origin'] == "DicomProtocol":
            today = date.today().isoformat()
            calledAET = firstInstanceMetadata['CalledAET'].upper()
            remoteAET = firstInstanceMetadata['RemoteAET']
            remoteIP = firstInstanceMetadata['RemoteIP']
            patientName = studyMetadata['PatientMainDicomTags']['PatientName']
            accession = studyMetadata['MainDicomTags']['AccessionNumber']
            studyInstanceUID = studyMetadata['MainDicomTags']['StudyInstanceUID']
            studyDate = studyMetadata['MainDicomTags']['StudyDate']
            dob = studyMetadata['PatientMainDicomTags']['PatientBirthDate']

        ##------------------------------
        ## Optional Data
        ##------------------------------
        #This section defines the DICOM metadata that is either optional or has failed as the metadata is not included by some Sites
            #Study Description
            try:
                studyDescription = studyMetadata['MainDicomTags']['StudyDescription']
            except KeyError:
                studyDescription = "UNKNOWN"

            #InstituitionName
            try:
                institutionName = studyMetadata['MainDicomTags']['InstitutionName']
            except KeyError:
                institutionName = "UNKNOWN"          
                
            ##------------------------------             
            ## Write to CSV - Input
            ##------------------------------
            Input_data_to_append = ['Received', today, calledAET, remoteAET, remoteIP, patientName, accession, studyInstanceUID, studyDate, dob, studyDescription, institutionName]
            csvfile = open(ORTHANC_TRANSFERS_CSV_PATH,'a',newline='')
            writer = csv.writer(csvfile)
            writer.writerows([Input_data_to_append])
            csvfile.close()
            
    ##------------------------------
    ## Labelling Sites and transfer Date
    ##------------------------------
            orthanc.RestApiPut(f"/studies/{resourceId}/labels/--PENDING", "{}")
            orthanc.RestApiPut(f"/studies/{resourceId}/labels/FROM_{remoteAET}", "{}")
            orthanc.RestApiPut(f"/studies/{resourceId}/labels/{calledAET}", "{}")
            orthanc.RestApiPut(f"/studies/{resourceId}/labels/{today}", "{}")


    ##------------------------------
    ## Set Routing Flags
    ##------------------------------
            # Has Autoroute been completed?
            success = False
            # Autoroute (Default True)
            routingRequired = True     
 
    ##------------------------------
    ## Destination List
    ##------------------------------
            match calledAET:
            ##------------------------------
            ## Current Implementation
            ##------------------------------
            ##------------------------------
            ## Facility 1
            ##------------------------------    
                case "PACSMODALITY1":
                    success = AutoRouteToModality("Dest1", resourceId)  
                case "PACSMODALITY2":
                    success = AutoRouteToModality("Dest2", resourceId)
                case "PACSMODALITY3":
                    success = AutoRouteToModality("Dest3", resourceId)
                case "PACSMODALITY4":
                    success = AutoRouteToModality("Dest4", resourceId)
         
        ##------------------------------ 
        ##Intended for Orthanc
        ##------------------------------
                case "ORTHANC":
                    success = True
                    routingRequired = False
                    # Delete PENDING label
                    orthanc.RestApiDelete(f"/studies/{resourceId}/labels/--PENDING")
                    # Create COMPLETED label
                    orthanc.RestApiPut(f"/studies/{resourceId}/labels/--COMPLETED", "{}")
                    # Create ACTION label
                    orthanc.RestApiPut(f"/studies/{resourceId}/labels/---ACTION", "{}")
              
    ##------------------------------
    ## No Match - Do not AutoRoute
    ##------------------------------
                case _:                 
                    # Delete PENDING label
                    orthanc.RestApiDelete(f"/studies/{resourceId}/labels/--PENDING")
                    # Create INVALID_CALLED_AET label
                    orthanc.RestApiPut(f"/studies/{resourceId}/labels/--INVALID_CALLED_AET", "{}")
                    # Create FAILED label
                    orthanc.RestApiPut(f"/studies/{resourceId}/labels/--FAILED", "{}")
                    orthanc.LogWarning(f"[AUTO-ROUTE JOB FAILURE] Called AET: {calledAET} was improperly specified, auto-route job was not created as destination could not be determined")                
    ##------------------------------
    ## Log Outcome
    ##------------------------------

            if success:
                if routingRequired == True:
                    orthanc.LogWarning(f"[AUTO-ROUTE JOB COMPLETED] Accession {accession} with Study Instance UID {studyInstanceUID} for Patient {patientName} auto-route job created from {remoteAET}:{remoteIP} to {calledAET}")
                    Input_data_to_append = ['Completed', today, calledAET, remoteAET, remoteIP, patientName, accession, studyInstanceUID, studyDate, dob, studyDescription, institutionName]
                    csvfile = open(ORTHANC_TRANSFERS_CSV_PATH,'a',newline='')
                    writer = csv.writer(csvfile)
                    writer.writerows([Input_data_to_append])
                    csvfile.close()
                else:
                    orthanc.LogWarning(f"[AUTO-ROUTE JOB NOT REQUIRED SENT TO ORTHANC ONLY] Accession {accession} with Study Instance UID {studyInstanceUID} for Patient {patientName} received from {remoteAET}:{remoteIP} to {calledAET}")
                    Input_data_to_append = ['Failed', today, calledAET, remoteAET, remoteIP, patientName, accession, studyInstanceUID, studyDate, dob, studyDescription, institutionName]
                    csvfile = open(ORTHANC_TRANSFERS_CSV_PATH,'a',newline='')
                    writer = csv.writer(csvfile)
                    writer.writerows([Input_data_to_append])
                    csvfile.close()
            else: # When not successful
                orthanc.LogWarning(f"[AUTO-ROUTE JOB FAILED] ERROR: Accession {accession} with Study Instance UID {studyInstanceUID} for Patient {patientName} auto-route job FAILED from {remoteAET}:{remoteIP} to {calledAET}")

               
orthanc.RegisterOnChangeCallback(OnChange)
##------------------------------