troggle/core/views/uploads.py

import re, os, socket
import subprocess
import json
import settings
import urllib
import operator

from pathlib import Path
from functools import reduce

from django import forms

from django.conf import settings
from django.urls import reverse
from django.db.models import Q
from django.http import HttpResponse, HttpResponseRedirect
from django.shortcuts import render
from django.template import Context, loader
from django.core.files.storage import FileSystemStorage, default_storage
from django.core.exceptions import ObjectDoesNotExist, MultipleObjectsReturned


#from troggle import settings
from troggle.parsers.imports import import_caves, import_people, import_surveyscans
from troggle.parsers.imports import import_logbooks, import_QMs, import_drawingsfiles, import_survex
from troggle.parsers.scans import contentsjson
# from databaseReset import reinit_db # don't do this. databaseRest runs code *at import time*
from troggle.core.models.troggle import DataIssue
from troggle.core.models.troggle import Expedition, Person, PersonExpedition
from troggle.core.models.caves import LogbookEntry, QM, Cave, PersonTrip
from troggle.core.models.survex import DrawingFile, Wallet
from troggle.core.views.scans import oldwallet, walletindex
from troggle.core.views.caves import getCave

from .auth import login_required_if_public
#from django.views.decorators.csrf import ensure_csrf_cookie, csrf_exempt

'''File upload 'views' 
'''

todo = '''
- Register uploaded filenames in the Django db without needing to wait for a reset & bulk file import

- Refactor scanupload() as it contains all the wallets 'complaints' code from the old script wallets.py

- Need to validate uploaded file as being a valid image file, not a dubious script or hack

- Write equivalent GPX upload form system, similar to scanupload() but in expofiles/gpslogs/
  Need to validate it as being a valid GPX file using an XML parser, not a dubious script or hack
  
- Validate Tunnel & Therion files using an XML parser in dwgupload(). Though Julian says tunnel is only mostly correct XML

- Validate image files using a magic recogniser in scanupload() https://pypi.org/project/reportlab/ or 
  https://stackoverflow.com/questions/889333/how-to-check-if-a-file-is-a-valid-image-file

- Enable folder creation in dwguploads or as a separate form

'''
wallet_blank_json = {
 "cave": "", 
 "date": "", 
 "description url": "1623/XXX", 
 "description written": False, 
 "electronic survey": False, 
 "elev drawn": False, 
 "elev not required": False, 
 "name": "", 
 "people": [
  "Unknown"
 ], 
 "plan drawn": False, 
 "plan not required": False, 
 "qms written": False, 
 "survex file": [], 
 "survex not required": False, 
 "website updated": False}

class FilesForm(forms.Form):  # not a model-form, just a form-form
    uploadfiles = forms.FileField() 
     
class FilesRenameForm(forms.Form):  # not a model-form, just a form-form
    uploadfiles = forms.FileField() 
    renameto = forms.CharField(strip=True, required=False)

class WalletGotoForm(forms.Form):  # not a model-form, just a form-form
    walletgoto = forms.CharField(strip=True, required=False) 
    
class TextForm(forms.Form):  # not a model-form, just a form-form
    photographer = forms.CharField(strip=True) 

class WalletForm(forms.Form):  # not a model-form, just a form-form
    descriptionw = forms.CharField(strip=True, required=False) 
    people = forms.CharField(strip=True, required=False) 
    survexnr = forms.CharField(strip=True, required=False) 
    qmsw = forms.CharField(strip=True, required=False) 
    date = forms.CharField(strip=True, required=True) # the only required field
    websiteupt = forms.CharField(strip=True, required=False) 
    elevnr = forms.CharField(strip=True, required=False) 
    cave = forms.CharField(strip=True, required=False) 
    psg = forms.CharField(strip=True, required=False) 
    plannr = forms.CharField(strip=True, required=False) 
    electronic = forms.CharField(strip=True, required=False) 
    pland = forms.CharField(strip=True, required=False) 
    elevd = forms.CharField(strip=True, required=False) 
    url = forms.CharField(strip=True, required=False) 
    survex = forms.CharField(strip=True, required=False) 

xlate = {"url": "description url",
        "descriptionw": "description written",
        "people": "people",
        "date": "date",
        "cave": "cave",
        "plannr": "plan not required",
        "survexnr": "survex not required",
        "qmsw": "qms written",
        "elevnr": "elev not required",
        "websiteupt": "website updated",
        "electronic": "electronic survey",
        "pland": "plan drawn",
        "elevd": "elev drawn",
        "psg": "name", # a name for this wallet
        "survex": "survex file",
        }

def get_complaints(complaints, waldata, svxfiles, files, wallet, wurl):
    '''Taken from old script wallets.py and edited to make more comprehensible
    Loads the survex files names and processes all complaints
    
    '''
    # If skipping through the wllets on the upload form, the wallet may not yet exist
    try:
        w = Wallet.objects.get(walletname=wallet)
    except ObjectDoesNotExist:
        return None, None
        
    ticks = w.get_ticks()
    
    # Date
    if not waldata["date"]:
        complaints.append("A date is mandatory. No data can be updated or edited unless you specify a date. Look in the survex file if there is one.") 

    # People
    if waldata["people"]==["NOBODY"] or waldata["people"]==["Unknown"]:
        complaints.append("Someody must have done this. Look in the survex file, or in the logbook entries for this date, for the people who created this data.") 
        
    # survex, but get_ticks has already done much of this ??
    survex_complaint = ""

    if waldata["survex file"]:
        if not type(waldata["survex file"])==list: # a string also is a sequence type, so do it this way
            waldata["survex file"] = [waldata["survex file"]]       
        for svx in waldata["survex file"]:
            if svx !="":
                svxfiles.append(svx)
                if not (Path(settings.SURVEX_DATA) / svx).is_file():
                    file_complaint = f"{wallet} Incorrect survex file name in {wallet} wallet data. {svx} was not found in LOSER repo"
                    complaints.append(file_complaint)
                    message = f"! {file_complaint}"
                    print(message)
                    DataIssue.objects.update_or_create(parser='scans', message=message, url=wurl) # set URL to this wallet folder

    if waldata["survex not required"] and waldata["survex file"] != "":
        survex_complaint = "Survex is stated as not required and yet there is a survex file!"    
    if not waldata["survex not required"] and waldata["survex file"] == "":
        survex_complaint = "A survex file is required, but has not been specified!"    
    if survex_complaint:
        complaints.append(survex_complaint)


    # Notes required
    if ticks['N'] != "green": 
        complaints.append("The notes needs scanning (or renaming): no noteNN.jpg or XXnote.jpg file found; and this is not an electronic survey.") 

    # Plan drawing required
    if ticks['P'] != "green": 
         complaints.append("The plan needs drawing (or renaming, or tick 'Plan drawn' checkbox or 'Plan not required' checkbox): no planNN.jpg or XXplan.jpg file found.") 

    # Elev drawing required
    if ticks['E'] != "green": 
        complaints.append("The elevation needs drawing (or renaming, or tick 'Elev drawn' checkbox or 'Elev not required' checkbox): no elevNN.jpg or XXelev.jpg file found.") 

    # ETherion
    if ticks['T'] != "green": 
        complaints.append("Tunnel or Therion drawing files need drawing. Or if this an electronic survey, please tick the 'Electronic survey' checkbox.") 
     
    # Description
    if not waldata["description written"]: 
        complaints.append("The guidebook description needs writing into the survex file. Tick the 'Cave description written' checkbox when this is done.") 
    # QMs
    if not waldata["qms written"]:
        complaints.append("The QMs needs writing into the survex file. Tick the 'QMs written' checkbox when this is done.") 

    # Website
    if not waldata["website updated"]:
        complaints.append("The cave description website is marked as needing updating using the guidebook description from the survex file. Tick the 'Website updated' checkbox when this is done.")

    # FInd the cave, if it exists
    if waldata["cave"]:
        try:
            caveid = waldata["cave"]
            caveid = caveid.replace("/","-")
            caveobject = getCave(caveid)   
            print(f'getCave for id "{waldata["cave"]}" {caveobject}')
            if not caveobject.url == waldata["description url"]:
                complaints.append(f'The URL of cave description \"{waldata["description url"]}\" does not match the one on record for this cave which is: "{caveobject.url}". If the wallet is not for a cave, put a useful URL here.')
        except Cave.MultipleObjectsReturned: 
            complaints.append(f'The cave ID \'{waldata["cave"]}\' is AMBIGUOUS. Please fix it.')
            caveobject = None
        except ObjectDoesNotExist:
            complaints.append(f'The cave ID \'{waldata["cave"]}\' is not recognised. Please fix it.')
            caveobject = None
    else:
        complaints.append(f'No cave ID is given. Please give some text, even if it is just "surface survey" or "scraps found in hut"')
        caveobject = None
         

    return complaints, caveobject
    
# @login_required_if_public
def scanupload(request, path=None):
    '''Upload scanned image files into a wallet on /expofiles
    Also display AND EDIT the contents.json data in the wallet.
    
    The Wallet object and the contents.json file are created when the user
    first uploads files. 
    
    This does NOT use a Django model linked to a Django form. Just a simple Django form.
    You will find the Django documentation on forms very confusing,
    as it covers many very differnet things we do not need. This is simpler.
    
    This subsumes much of the code which was in the old wallets.py script and so this function is very long
    indeed and needs refactoring.
    
    REWRITE bits using the ticklist, dateify, caveify, populate etc utility functions in core.view.scans.py 
    '''
    git = settings.GIT
    filesaved = False
    actual_saved = []
    
    def save_json(jsondict):
        newfolder = contents_path.parent
        print(f'---  wallet directory in :drawings: repo {newfolder=}')
        if not os.path.exists(contents_path.parent):
            print(f'--- No wallet directory in :drawings: repo, so creating it')
            os.makedirs(contents_path.parent)
        
        with open(contents_path, "w") as jfile:
            json.dump(jsondict, jfile, indent = 1)
        print(f'--- FINISHED saving to JSON at {contents_path}')
        
    def make_wallet(walletname):
        '''We need a wallet Object so that the django template stuff can find the files
        '''
        try:
            w, created = Wallet.objects.get_or_create(walletname=walletname)
            print(f'wallet string {walletname}, wallet object {w} created new?: {created}')   
            if created:
                w.fpath = Path(settings.SCANS_ROOT, walletname[0:4], walletname)
                w.save()
        except:
             print(f'wallet string {walletname}, FAIL TO GET or create WALLET OBJECT')
             raise

    def commit_json(waldata):
        destfolder = contents_path.parent
        dr_add = subprocess.run([git, "add", contentsjson], cwd=destfolder, capture_output=True, text=True)
        if dr_add.returncode != 0:
            msgdata = 'Ask a nerd to fix this.\n--' + dr_add.stderr + '\n--' + dr_add.stdout  + '\n--return code: ' + str(dr_add.returncode)
            message = f'CANNOT git on server for this file {contentsjson}. Edits saved but not added to git.\n\n' + msgdata
            print(message)
            return render(request,'errors/generic.html', {'message': message})
        else:
            if socket.gethostname() != "expo":
                comment = f"on dev machine '{socket.gethostname()}' " 
            else:
                comment = ""
            if "cave" in waldata:
                label = waldata["cave"]
            else:
                if "name" in waldata:
                    label = waldata["name"]
                else:
                    label = ""
        
            dr_commit = subprocess.run([git, "commit", "-m", f'JSON update wallet {wallet} {label} {comment}'], cwd=destfolder, capture_output=True, text=True)
            # This produces return code = 1 if it commits OK
            if dr_commit.returncode != 0:
                msgdata = 'Ask a nerd to fix this.\n\n' + dr_commit.stderr + '\n\n' + dr_commit.stdout  + '\n\nreturn code: ' + str(dr_commit.returncode)
                message = f'Error code with git on server for this {contentsjson}. File is added to git, but NOT committed.\n' + msgdata
                print(message)
                return render(request,'errors/generic.html', {'message': message})

    
    checkboxes = ["description written", "survex not required", "qms written", "website updated",
            "plan not required", "plan drawn", "elev not required", "elev drawn", "electronic survey" ]
    if path:
        wallet = urllib.parse.unquote(path)
    else:
        wallet = "2022#01" # improve this later

    year = wallet[:4]
    try:
        if int(year) <= 1998: 
            #print(f'! - FORM scanupload - start {wallet} REDIRECT TO OLDWALLET')
            return(oldwallet(request, path))
    except:
        # if nonumeric wallet name for example
        return(oldwallet(request, path))
   
    
    if str(wallet).lower().endswith('indexpages'):
        # print(f'! - FORM scanupload - start {wallet} REDIRECT TO OLDWALLET')
        return(walletindex(request, path))

    if not re.match('(19|20)\d\d[:#]\d\d', wallet):
        wallet = "2022:01" # improve this later
    # print(f'! - FORM scanupload - start {wallet}')
    
    if path:
        pass
        # print(f'! - FORM scanupload - start wallet:{wallet}: path:{path}:')
    if int(year) < 1977: 
        year = "1977"
    if int(year) > 2050: 
        year = "2050"
    nexty = f'{int(year)+1}'
    prevy = f'{int(year)-1}'


    wnumber = wallet[5:]
    next = f'{int(wnumber)+1:02d}'
    prev = f'{int(wnumber)-1:02d}'
    
    if int(wnumber) == 0:
        prev = f'{int(wnumber):02d}'

    wurl = f"/scanupload/{wallet}".replace('#', ':')     
    wallet = wallet.replace(':','#')
    dirpath = Path(settings.SCANS_ROOT, year, wallet)
    contents_path = Path(settings.DRAWINGS_DATA, "walletjson") / year / wallet / contentsjson
    
    form = FilesForm()
   
    if request.method == 'POST':
        if "psg" in request.POST:              
            formj = WalletForm(request.POST)
            # Beware. All fields returned as strings. Must re-type them as lists etc. before using or re-saving
            # Also lots of hassle with lists of strings interpreted as a single string
            # Unset checkboxes do not return any value, checked ones return "True". So need initialising to False
            if formj.is_valid():
                posted = request.POST.copy()
                posted.pop("csrfmiddlewaretoken") # discard this
                wd = wallet_blank_json
                for f in checkboxes:
                    wd[f] = False
                    #print(f'--- wd ${f}$  - {wd[f]}')
                for f in posted:
                    wd[xlate[f]] = posted[f].replace("\'", "\"")

                    if posted[f] =="True":
                        wd[xlate[f]] = True

                wd["people"] = wd["people"][1:-1].replace("\"", "").split(",")
                for i, elem in enumerate(wd["people"]):
                    wd["people"][i] = elem.strip()
                    
                #print(f'--- ${wd["survex file"]}$  - {type(wd["survex file"])}')
                if wd["survex file"]: # allow for no survex file at all
                    if wd["survex file"][0] == '[':
                        wd["survex file"] = wd["survex file"][1:-1]
                    wd["survex file"] = wd["survex file"].replace("\"", "").split(",")
                    for i, elem in enumerate(wd["survex file"]):
                       wd["survex file"][i] = elem.strip()
                    #print(f'--- {wd["survex file"]} - {type(wd["survex file"])}')

                save_json(wd)
                make_wallet(wallet)
                commit_json(wd)
                
            else:
                print(f'--- INVALID JSON Update form submitted')
                print(formj.errors)
                return render(request,'errors/generic.html', {'message': formj.errors})

        elif "walletgoto" in request.POST:  # not editing wallet data, uploading a file.. going direct to a named wallet
            formg = WalletGotoForm(request.POST,request.FILES) 
            if formg.is_valid():
                walletgoto = request.POST["walletgoto"]
               
                return HttpResponseRedirect(f'/scanupload/{walletgoto.replace("#",":")}')
                
        else: # not editing wallet data, uploading a file..
            form = FilesForm(request.POST,request.FILES)
     
            if form.is_valid():
                #f = request.FILES["uploadfiles"]
                multiple = request.FILES.getlist('uploadfiles')
                fs = FileSystemStorage(os.path.join(dirpath)) # creates wallet folder if necessary
                
                wd = wallet_blank_json # clean this out
                waldata = {}  # clean this out
                actual_saved = []
                if multiple:
                    for f in multiple:
                        try: # crashes in Django os.chmod call if on WSL, but does save file!
                            saved_filename = fs.save(f.name, content=f) 
                        except:
                            print(f'\n !! Permissions failure ?! on attempting to save file {f.name}')
                            if 'saved_filename' in locals():
                                if saved_filename.is_file():
                                    actual_saved.append(saved_filename)
                                    # print(f'! - FORM scanupload multiple {actual_saved}')
                                    filesaved = True
                    save_json(wallet_blank_json)
                    make_wallet(wallet)
                    commit_json(waldata)
    files = []
    dirs = []
    # print(f'! - FORM scanupload - start {wallet} {dirpath}')
    if dirpath.is_dir():
        create = False # wallet exists becausse folder exists, even if nothing in it
        try:
            for f in dirpath.iterdir():
                if f.is_dir():
                    dirs.append(f.name)
                if f.is_file():
                    files.append(f.name)
        except FileNotFoundError:
            files.append('(no wallet yet. It would be created if you upload a scan and then save the form with a date.)')
    else:
           create = True
         
    if len(files) >0 :
        files = sorted(files)
        
    if dirs:
        dirs = sorted(dirs)
        
    waldata = {}   
    if contents_path.is_file(): 
        create = False # yes wallet exists becaue JSON exists, even if no files in the surveyscans folder, or even if that folder does not exist
        with open(contents_path) as json_file:
            try:
                waldata = json.load(json_file)
            except:
                message = f"! {wallet} Failed to load {contents_path} JSON file"
                print(message)
                DataIssue.objects.create(parser='scans', message=message, url=wurl)  # set URL to this wallet folder
                raise
    cave =""
    psg = ""
    chkplannr = ""
    chkpland = ""
    svxfiles = []
    checked = {}
    context = {}
    if waldata:
        if not waldata["people"]:
            waldata["people"]=["NOBODY"]
        if not type(waldata["people"])==list: 
            if waldata["people"][0] == '"':
                waldata["people"] = waldata["people"][1:-1]
            waldata["people"] = list(waldata["people"])

        if not waldata["description url"]:
            waldata["description url"]=""
        if waldata["cave"]:
            cave =  waldata["cave"] # text string
        if waldata["name"]:
            psg =  waldata["name"]

        
        #Survex and survex complaints
        complaints, caveobject = get_complaints([], waldata, svxfiles, files, wallet, wurl)

     
        for f in checkboxes:
             if waldata[f]:
                 checked[f] = "checked"
                 
        survexsize =  str(min(len(str(waldata["survex file"])), 46))
                 
        context = {'year': year, 'prev': prev, 'next': next, 'prevy': prevy, 'nexty': nexty,
                'files': files, 'dirs': dirs, 'waldata': waldata, 'svxfiles': svxfiles,
                'checked': checked,
                'create': create, 
                'complaints': complaints,
                'caveobject': caveobject,
                'people':  waldata["people"], 'peoplesize': str(len(str(waldata["people"]))),
                'filesaved': filesaved, 'actual_saved': actual_saved }

        return render(request, 'walletform.html', 
            {'form': form, 'wallet': wallet, **context, 
            'date': waldata["date"],
            'url':  waldata["description url"], 'urlsize': str(len(str(waldata["description url"]))),
            'survex': waldata["survex file"], 'survexsize': survexsize,
            'cave': cave, 'psg': psg, 'psgsize': str(max(12,len(str(psg))))})
    else: # no wallet here
        context = {'year': year, 'prev': prev, 'next': next, 'prevy': prevy, 'nexty': nexty,
                'files': files, 'dirs': dirs, 'waldata': waldata, 'svxfiles': svxfiles,
                'checked': checked,
                'create': create, 
                'people':  "", 'peoplesize': 12,
                'filesaved': filesaved, 'actual_saved': actual_saved }
        
        return render(request, 'walletform.html', 
            {'form': form, 'wallet': wallet, **context, 
            'date': "",
            'url':  "", 'urlsize': 12,
            'survex': "", 'survexsize': 46,
            'cave': cave, 'psg': psg, 'psgsize': 12})

@login_required_if_public
def photoupload(request, folder=None):
    '''Upload photo image files into /expofiles/photos/<year>/<photographer>/
    This does NOT use a Django model linked to a Django form. Just a simple Django form.
    You will find the Django documentation on forms very confusing, This is simpler.
    
        
    When uploading from a phone, it is useful to be able to rename the file to something 
    meaningful as this is difficult to do on a phone. Previously we had assumed files would
    be renamed to something useful before starting the upload.
    Unfortunately this only works when uploading one file at at time ,
    inevitable once you think about it.
    '''
    year = settings.PHOTOS_YEAR
    filesaved = False
    actual_saved = []
 
    context = {'year': year, 'placeholder': "AnathemaDevice"}
    
    yearpath = Path(settings.PHOTOS_ROOT, year)
    
    if folder == str(year) or folder == str(year) +"/":
        folder = None
    
    if folder is None:
        folder = "" # improve this later
        dirpath = Path(settings.PHOTOS_ROOT, year)
        urlfile = f'/expofiles/photos/{year}'
        urldir  = f'/photoupload/{year}'
    else: # it will contain the year as well as the photographer
        dirpath = Path(settings.PHOTOS_ROOT, folder)
        if dirpath.is_dir():
            urlfile = f'/expofiles/photos/{folder}'
            urldir  = Path('/photoupload') / folder
        else:
            folder = "" # improve this later
            dirpath = Path(settings.PHOTOS_ROOT, year)
            urlfile = f'/expofiles/photos/{year}'
            urldir  = f'/photoupload/{year}'
      
        
    form = FilesRenameForm()
    formd = TextForm()  
     
    if request.method == 'POST':
        if "photographer" in request.POST:              
            formd = TextForm(request.POST)
            if formd.is_valid():
                newphotographer = request.POST["photographer"]
                (yearpath / newphotographer).mkdir(exist_ok=True)
        else:
            form = FilesRenameForm(request.POST,request.FILES)
            if form.is_valid():
                f = request.FILES["uploadfiles"]
                multiple = request.FILES.getlist('uploadfiles')
                # NO CHECK that the files being uploaded are image files
                fs = FileSystemStorage(dirpath)
                
                renameto = request.POST["renameto"]
               
                actual_saved = []
                if multiple:                   
                    if len(multiple) == 1:
                        if renameto != "":
                            try: # crashes in Django os.chmod call if on WSL, but does save file!
                                saved_filename = fs.save(renameto, content=f) 
                            except:
                                print(f'\n !! Permissions failure ?! on attempting to save file {f.name}')
                                if 'saved_filename' in locals():
                                    if saved_filename.is_file():
                                        actual_saved.append(saved_filename)
                                        filesaved = True  
                        else: # multiple is the uploaded content
                            try: # crashes in Django os.chmod call if on WSL, but does save file!
                                saved_filename = fs.save(f.name, content=f) 
                            except:
                                print(f'\n !! Permissions failure ?! on attempting to save file {f.name}')
                                if 'saved_filename' in locals():
                                    if saved_filename.is_file():
                                        actual_saved.append(saved_filename)
                                        filesaved = True    
                    else: # multiole is a list of content
                        for f in multiple:
                            try: # crashes in Django os.chmod call if on WSL, but does save file!
                                saved_filename = fs.save(f.name, content=f) 
                            except:
                                print(f'\n !! Permissions failure ?! on attempting to save file {f.name}')
                                if 'saved_filename' in locals():
                                    if saved_filename.is_file():
                                        actual_saved.append(saved_filename)
                                        filesaved = True    
    files = []
    dirs = []
    try:
        for f in dirpath.iterdir():
            if f.is_dir():
                dirs.append(f.name)
            if f.is_file():
                files.append(f.name)           
    except FileNotFoundError:
        files.append('(no folder yet - would be created)')
    if len(files) >0 :
        files = sorted(files)
        
    if dirs:
        dirs = sorted(dirs)

    return render(request, 'photouploadform.html', 
        {'form': form, **context, 'urlfile': urlfile, 'urldir': urldir,'folder': folder, 'files': files, 'dirs': dirs, 'filesaved': filesaved, 'actual_saved': actual_saved})

@login_required_if_public
def dwgupload(request, folder=None, gitdisable='no'):
    '''Upload DRAWING files (tunnel or therion) into the upload folder in :drawings
    AND registers it into the :drawings: git repo.
    
    This does NOT use a Django model linked to a Django form. Just a simple Django form.
    You will find the Django documentation on forms very confusing, This is simpler.
    
    We could validate the uploaded files as being a valid files using an XML parser, not a dubious script or hack

    
    We use get_or_create instead of simply creating a new object in case someone uploads the same file
    several times in one session, and expects them to be overwritten in the database. Although
    the actual file will be duplicated in the filesystem with different random name ending.
    '''
    def dwgvalid(name):
        if name in [ '.gitignore', ]:
            return False
        if Path(name).suffix.lower() in ['.xml', '.th', '.th2', '', '.svg', '.txt']:
            return True # dangerous, we should check the actual file binary signature
        return False

    def dwgvaliddisp(name):
        '''OK to display, even if we are not going to allow a new one to be uploaded
        '''
        if name in [ '.gitignore', ]:
            return False
        if Path(name).suffix.lower() in ['.xml', '.th', '.th2', '', '.svg', '.txt', '.jpg', '.jpeg', '.png', '.pdf', '.top', '.topo']:
            return True # dangerous, we should check the actual file binary signature
        return False

    filesaved = False
    actual_saved = []
    refused = []
    doesnotexist = ''
    # print(f'! - FORM dwgupload - start "{folder}" - gitdisable "{gitdisable}"')
    if folder is None:
        folder = "" # improve this later
        dirpath = Path(settings.DRAWINGS_DATA)
        urlfile = '/dwgdataraw'
        urldir  = '/dwgupload'
    else:
        dirpath = Path(settings.DRAWINGS_DATA, folder)
        urlfile = Path('/dwgdataraw/') / folder
        urldir  = Path('/dwgupload/') / folder
    
    form = FilesForm()
    
    if request.method == 'POST':
        form = FilesForm(request.POST,request.FILES)
        if form.is_valid():
            # print(f'! - FORM dwgupload - POST valid: "{request.FILES["uploadfiles"]}" ')
            f = request.FILES["uploadfiles"]
            multiple = request.FILES.getlist('uploadfiles')
            fs = FileSystemStorage(os.path.join(settings.DRAWINGS_DATA, folder))
           
            actual_saved = []
            refused = []
            
            # GIT see also core/views/expo.py editexpopage()
            # GIT see also core/models/cave.py writetrogglefile()
            if gitdisable != 'yes': # set in url 'dwguploadnogit/'
                git = settings.GIT
            else:
                git = 'echo'
                # print(f'git DISABLED {f.name}')

            if multiple:
                for f in multiple:
                    # print(f'! - FORM dwgupload - file {f} in {multiple=}')
                    if dwgvalid(f.name):
                        try: # crashes in Django os.chmod call if on WSL without metadata drvfs, but does save file!
                            saved_filename = fs.save(f.name, content=f) 
                        except:
                            print(f'! - FORM dwgupload - \n!! Permissions failure ?! on attempting to save file {f.name}. Attempting to continue..')
                        if 'saved_filename' in locals():
                            if Path(dirpath, saved_filename).is_file():
                                actual_saved.append(saved_filename)
                                if gitdisable != 'yes':
                                    dr_add = subprocess.run([git, "add", saved_filename], cwd=dirpath, capture_output=True, text=True)
                                    msgdata =  dr_add.stderr + '\n' + dr_add.stdout  + '\nreturn code: ' + str(dr_add.returncode)
                                    # message = f'! - FORM dwgupload - Success: git ADD on server for this file {saved_filename}.' + msgdata
                                    # print(message)
                                    if dr_add.returncode != 0:
                                        msgdata = 'Ask a nerd to fix this.\n\n' + dr_add.stderr + '\n\n' + dr_add.stdout  + '\n\nreturn code: ' + str(dr_add.returncode)
                                        message = f'! - FORM dwgupload - CANNOT git ADD on server for this file {saved_filename}. Edits saved but not added to git.\n' + msgdata
                                        print(message)
                                        return render(request,'errors/generic.html', {'message': message})
                                dwgfile, created = DrawingFile.objects.get_or_create(dwgpath=saved_filename, dwgname=Path(f.name).stem, filesize=f.size)  
                                dwgfile.save()
                            else:
                                message = f'! - FORM dwgupload - NOT A FILE {Path(dirpath, saved_filename)=}. '
                                print(message)
                        else:
                            message = f'! - FORM dwgupload - Save failure for {saved_filename}. Changes NOT saved.'
                            print(message)
                            return render(request,'errors/generic.html', {'message': message})
                            
                        if saved_filename != f.name:
                            # message = f'! - FORM dwgupload - Save RENAME {f.name} renamed as {saved_filename}. This is OK.'
                            # print(message)
                            pass
                       
                    else:
                        refused.append(f.name)
                        # print(f'REFUSED {f.name}')
                        
            if actual_saved: 
                filesaved = True
                if len(actual_saved) > 1:
                    dots = "..."
                else:
                    dots = ""
                if gitdisable != 'yes':
                    dr_commit = subprocess.run([git, "commit", "-m", f'Drawings upload - {actual_saved[0]}{dots}'], cwd=dirpath, capture_output=True, text=True)
                    # message = f'! - FORM dwgupload - For uploading {actual_saved[0]}{dots}. Edits saved, added to git, and COMMITTED.\n' + msgdata
                    # print(message)
                    # This produces return code = 1 if it commits OK
                    if dr_commit.returncode != 0:
                        msgdata = 'Ask a nerd to fix this.\n\n' + dr_commit.stderr + '\n' + dr_commit.stdout  + '\nreturn code: ' + str(dr_commit.returncode)
                        message = f'! - FORM dwgupload -Error code with git on server for this {actual_saved[0]}{dots}. Edits saved, added to git, but NOT committed.\n' + msgdata
                        print(message)
                        return render(request,'errors/generic.html', {'message': message})
                else:
                    print(f' git disabled "{git=}"')
            else:# maybe all were refused by the suffix test in dwgvalid()
                message = f'! - FORM dwgupload - Nothing actually saved. All were refused. {actual_saved=}'
                print(message)

    files = []
    dirs = []
    # print(f'! - FORM dwgupload - start {folder=} \n"{dirpath=}" \n"{dirpath.parent=}" \n"{dirpath.exists()=}"')
    try:
        for f in dirpath.iterdir():
            if f.is_dir():
                if f.name not in ['.git' ]:
                    dirs.append(f.name)
                    continue
            if f.is_file():
                if dwgvaliddisp(f.name): 
                    files.append(f.name)
                    continue
    except FileNotFoundError:
        doesnotexist = True
    if files:
        files = sorted(files)
        
    if dirs:
        dirs = sorted(dirs)

    return render(request, 'dwguploadform.html', 
        {'form': form, 'doesnotexist': doesnotexist, 'urlfile': urlfile, 'urldir': urldir,'folder': folder, 'files': files, 'dirs': dirs, 'filesaved': filesaved, 'actual_saved': actual_saved, 'refused': refused})