import subprocess
from datetime import datetime, timezone
from pathlib import Path

from django import forms
from django.core.files.storage import FileSystemStorage
from django.shortcuts import render, redirect

import settings

from troggle.core.models.caves import GetCaveLookup
from troggle.core.models.logbooks import LogbookEntry, writelogbook, PersonLogEntry
from troggle.core.models.survex import DrawingFile
from troggle.core.models.troggle import DataIssue, Expedition, PersonExpedition
from troggle.core.utils import alphabet_suffix, current_expo, sanitize_name, unique_slug
from troggle.parsers.people import GetPersonExpeditionNameLookup, known_foreigner

# from databaseReset import reinit_db # don't do this. databaseRest runs code *at import time*

from .auth import login_required_if_public

"""File upload 'views' 
Note that there are other file upload forms in views/wallet_edit.py
and that core/forms.py contains Django class-based forms for caves and entrances.
"""

todo = """
- Ideally we should validate uploaded file as being a valid file type, not a dubious script or hack
  Validate image files using a magic recogniser in walletedit()
  https://pypi.org/project/reportlab/   or 
  https://stackoverflow.com/questions/889333/how-to-check-if-a-file-is-a-valid-image-file

- Write equivalent GPX upload form system, similar to walletedit() 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, and it does fail at least one XML parser.
  
- parse the uploaded drawing file for links to wallets and scan files as done 
  in parsers/drawings.py

- Enable folder creation in dwguploads or as a separate form

- Enable file rename on expofiles, not just for /surveyscans/ (aka wallets)

- Make file rename utility less ugly.
"""

def create_new_lbe_slug(date):
    onthisdate = LogbookEntry.objects.filter(date=date)
    n = len(onthisdate)
    print(f" Already entries on this date: {n}\n {onthisdate}")
    
    suffix = alphabet_suffix(n+1)
        
    tid = f"{date}{suffix}"
    print(tid)
    return tid

def store_edited_entry_into_database(date, place, title, text, others, author, tu, slug):
    """saves a single logbook entry and related personlogentry items
    
    need to  select out *guest and foreign friends from others
    
    Rather similar to similarly named function in parsers/logbooks but circular reference prevents us using it directly,
    and they need refactoring anyway.
    """
    
    year = slug[0:4]
    expedition = Expedition.objects.get(year=year)
    cave = GetCaveLookup().get(place.lower())
    # print(f"{place} {cave=}")
    
    if LogbookEntry.objects.filter(slug=slug).exists():
        # oops.
        message = f" ! - DUPLICATE SLUG for logbook entry {date} - {slug}"
        DataIssue.objects.create(parser="logbooks", message=message)
        slug = slug + "_" + unique_slug(text,2)
    
    otherAttribs = {
        "place": place,
        "text": text,
        "expedition": expedition,
        "time_underground": tu,
        "cave_slug": str(cave),
        "title": f"{place} - {title}",
        # "other_people": others
    }
    coUniqueAttribs = {"slug": slug, "date": date }

    lbo = LogbookEntry.objects.create(**otherAttribs, **coUniqueAttribs)
    
    pt_list = []
    # These entities have to be PersonExpedition objects
    team = others.split(",")
    team.append(author)
    
    odds = []
    for name in team:
        name = name.strip()
        if len(name) > 0: 
            if name[0] == "*": # a name prefix of "*" is special, just a string.
                odds.append(name)
                print(f" - adding * special name '{name}'")
            else:
                try:
                    personyear = GetPersonExpeditionNameLookup(expedition).get(name.lower())
                    if not personyear:
                        odds.append(name)
                        print(f" - adding unrecognised expoer '{name}'")
                        if known_foreigner(name):
                            message = f" ! - Known foreigner: '{name}' in entry {slug=}"
                            print(message)
                        else:
                            message = f" ! - No name match for: '{name}' in entry {slug=}"
                            print(message)
                            DataIssue.objects.create(parser="logbooks", message=message)
                    else:                    
                        coUniqueAttribs = {"personexpedition": personyear, "nickname_used": name, "logbook_entry": lbo} # lbo is primary key
                        otherAttribs = {"time_underground": tu, "is_logbook_entry_author": (name==author)}
                        pt_list.append(PersonLogEntry(**otherAttribs, **coUniqueAttribs))

                except:
                    # This should not happen. We do not raise exceptions in that function
                    message = f" ! - EXCEPTION: '{name}' in entry {slug=}"
                    print(message)
                    DataIssue.objects.create(parser="logbooks", message=message)
                    raise
 
    PersonLogEntry.objects.bulk_create(pt_list)
    
    lbo.other_people = ", ".join(odds)
    print(f" - Saving other_people '{lbo.other_people}'")
    lbo.save()

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 TextForm(forms.Form):  # not a model-form, just a form-form
    photographer = forms.CharField(strip=True)
    
class ExpofileRenameForm(forms.Form):  # not a model-form, just a form-form
    renameto = forms.CharField(strip=True, required=False)
    
class LogbookEditForm(forms.Form):  # not a model-form, just a form-form
    author = forms.CharField(strip=True, required=False)
    
@login_required_if_public
def logbookedit(request, year=None, slug=None):
    """Edit a logbook entry
    
    This 'validates' the author as being on expo in the current year, but only indicates this by
    putting the text of the form prompt in red (same as for an invalid date, which is arguably more important).
    No check is done on the other people on the trip as this is picked up anyway by parsing on import
    and we don't really care at this point.
    
    If the author name is mispelled, noticed, and chnaged, then two logbook entries are created
    with sequential slugs ...b ...c etc. This is because we are doing validation on GET not on POST
    and we are not rewriting the URL when a slug gets set. Hmm.
    """
    def validate_year(year):
        try:
            expo = Expedition.objects.get(year=year)
        except:
            year = current_expo() # creates new Expedition object if needed
        return year
        
    def new_entry_form():
        return render(
            request,
            "logbookform.html",
            {
                "form": form,
                "year": year,
            },
        )
    def clean_tu(tu):
        if tu =="":
            return 0
        try:
            tu = float(tu)/1 # check numeric
        except:
            return 0
        return tu
    
    if not year:
        if not slug:
            year = current_expo()
        else:
            year = slug[0:4]
            try:
                year = str(int(year))  # but maybe slug was hand-edited to be a future year..
                year = validate_year(year) # so fix that
            except:
                year = current_expo()
            
    author = ""
    
    if request.method == "POST":
        form = LogbookEditForm(request.POST)
        if not form.is_valid():
            message = f'Invalid form response for logbook entry creating "{request.POST}"'
            print(message)
            return render(request, "errors/generic.html", {"message": message})
        else:
            # if there is no slug then this is probably a completely new lbe and we need to enter it into the db
            # otherwise it is an update
            # validation all to be done yet..
            date = request.POST["date"].strip()  
            author = request.POST["author"].strip()   # TODO check against personexpedition  on submit
            others = request.POST["others"].strip()    # TODO check each against personexpedition on submit
            place = request.POST["place"].strip().replace(' - ',' = ')  # no hyphens !
            title = request.POST["title"].strip()   
            entry = request.POST["text"].strip() 
            entry = entry.replace('\r','') # remove HTML-standard CR inserted from form.
            # entry = entry.replace('\n\n','\n<br />\n<br />\n') # replace 2 \n  with <br><br>
            # entry = entry.replace('<p>','<br />\n<br') # replace <p> tag  with <br><br>
            # entry = entry.replace('<p ','<br />\n<br') # replace <p> tag  with attributes with <br><br>
            # entry = entry.replace('<br>','<br />') # clean up previous hack
            tu = request.POST["tu"].strip()
            tu = clean_tu(tu)
            
            try:
                odate = datetime.strptime(date.replace(".", "-"), "%Y-%m-%d").date()
                dateflag = False
            except:
                odate = datetime.strptime(f"{year}-01-01", "%Y-%m-%d").date()
                print(f"! Invalid date string {date}, setting to {odate}")
                dateflag = True
            date = odate.isoformat()
            
            year = validate_year(year)
            expo = Expedition.objects.get(year=year)
            personyear = GetPersonExpeditionNameLookup(expo).get(author.lower())
            if personyear:
                authorflag = False
            else:
                authorflag = True
                print(f"! Unrecognised author: {author}")
            
            
            if not slug:
                # Creating a new logbook entry with all the gubbins
                slug = create_new_lbe_slug(date)
            else:
                # OK we could patch the object in place, but if the people on the trip have changed this 
                # would get very messy. So we delete it and recreate it and all its links
                print(f"- Deleting the LogBookEntry {slug}")
                LogbookEntry.objects.filter(slug=slug).delete()

            print(f"- Creating the LogBookEntry {slug}")
            year = slug[0:4]
            try:
                expedition = Expedition.objects.get(year=year)
            except Expedition.DoesNotExist:
                message = f'''! - This expo "{year}" not created yet
                It needs to be created before you can save a logbook entry.
                See /handbook/computing/newyear.html
                
                WHAT TO DO NOW:
                1. Press the Back button on your proswer to return to the screen where you typed up the entry,
                2. Copy the text of what you wrote into a new text file,
                3. Direct a nerd to fix this. It should take only a couple of minutes.'''
                print(message)
                return render(request, "errors/generic.html", {"message": message})
            store_edited_entry_into_database(date, place, title, entry, others, author, tu, slug)

                
            print(f"- Rewriting the entire {year} logbook to disc ")
            filename= "logbook.html"
            try:
                writelogbook(year, filename) # uses a template, not the code fragment below which is just a visible hint to logged on user
            except:
                message = f'! - Logbook saving failed - \n!! Permissions failure ?! on attempting to save file "logbook.html"'
                print(message)
                return render(request, "errors/generic.html", {"message": message})
            
            # Code fragment illustration - not actually what gets saved to database
            output = f'''

<div class="tripdate" id="{slug}">{date}</div>
<div class="trippeople"><u>{author}</u>, {others}</div>
<div class="triptitle">{place} - {title}</div>

{entry}

<div class="timeug">T/U {tu} hrs</div>
<hr />

'''
            # Successful POST
            # So save to database and then write out whole new logbook.html file
            
            # We do author validation on the form as displayed by GET, not at the moment of POST.
            # If we had JS validation then we could be more timely.
            git = settings.GIT
            dirpath = Path(settings.EXPOWEB) / "years" / str(year)
            lbe_add = subprocess.run(
                [git, "add", filename], cwd=dirpath, capture_output=True, text=True
            )
            msgdata = (
                lbe_add.stderr
                + "\n"
                + lbe_add.stdout
                + "\nreturn code: "
                + str(lbe_add.returncode)
            )
            message = f'! - FORM Logbook Edit {slug} - Success: git ADD on server for this file {filename}.' + msgdata
            print(message)
            if lbe_add.returncode != 0:
                msgdata = (
                    "Ask a nerd to fix this.\n\n"
                    + lbe_add.stderr
                    + "\n\n"
                    + lbe_add.stdout
                    + "\n\nreturn code: "
                    + str(lbe_add.returncode)
                )
                message = (
                    f"! - FORM Logbook Edit  - CANNOT git ADD on server for this file {filename}. {slug} edits saved but not added to git.\n"
                    + msgdata
                )
                print(message)
                return render(request, "errors/generic.html", {"message": message})
                
            lbe_commit = subprocess.run(
                [git, "commit", "-m", f"Logbook edited {slug}"],
                cwd=dirpath,
                capture_output=True,
                text=True,
            )
            message = f'! - FORM Logbook Edit - {filename}. {slug} edits saved, added to git, and COMMITTED.\n' + msgdata
            print(message)
            #This produces return code = 1 if it commits OK
            if lbe_commit.returncode != 0:
                msgdata = (
                    "Ask a nerd to fix this.\n\n"
                    + lbe_commit.stderr
                    + "\n"
                    + lbe_commit.stdout
                    + "\nreturn code: "
                    + str(lbe_commit.returncode)
                )
                message = (
                    f"! - FORM Logbook Edit -Error code with git on server for {filename}. {slug} edits saved, added to git, but NOT committed.\n"
                    + msgdata
                )
                print(message)
                return render(request, "errors/generic.html", {"message": message})
            
            return render(
                request,
                "logbookform.html",
                {
                    "form": form,
                    "year": year,
                    "date": date, "dateflag": dateflag,
                    "author": author, "authorflag": authorflag,
                    "others": others,
                    "place": place,
                    "title": title,
                    "tu": tu,
                    "entry": entry,
                    "output": output,
                    "slug": slug, 
                },
            )
    # GET here
    else:
        form = LogbookEditForm()
        year = validate_year(year)

        if not slug: # no slug or bad slug for an lbe which does not exist
            return new_entry_form()
        else:
            lbes = LogbookEntry.objects.filter(slug=slug)
            if not lbes:
                    return new_entry_form()
            else:
                if len(lbes) > 1:
                    return render(request, "object_list.html", {"object_list": lbes}) # ie a bug
                else:
                    lbe = lbes[0]
                print(f"{lbe}")
                tu = clean_tu(lbe.time_underground)
                
                people = []
                for p in lbe.personlogentry_set.filter(logbook_entry=lbe): # p is a PersonLogEntry object
                    if p.is_logbook_entry_author:
                        # author = p.personexpedition.person.fullname
                        author = p.nickname_used
                    else:
                        # people.append(p.personexpedition.person.fullname)
                        people.append(p.nickname_used)
                others =', '.join(people)
                print(f"{others=}")
                if lbe.other_people:
                    others = others + ", " + lbe.other_people
                lenothers = min(70,max(20, len(others)))
                print(f"{others=}")
 
                text = lbe.text
                rows = max(5,len(text)/50)
                return render(
                    request,
                    "logbookform.html",
                    {
                        "form": form,
                        "year": year,
                        "date": lbe.date.isoformat(),
                        "author": author,
                        "others": others,
                        "lenothers": lenothers,
                        "place": lbe.place,
                        "title": lbe.title.replace(f"{lbe.place} - ",""),
                        "tu": tu,
                        "entry": text,
                        "textrows": rows,
                        "slug": slug, 
                     },
                )
   
@login_required_if_public
def expofilerename(request, filepath):
    """Rename any single file in /expofiles/ - eventually.
    Currently this just does files within wallets i.e. in /surveyscans/
    and it returns control to the original wallet edit page
    """
    def is_rotatable(path):
        """If file is a JPG but has no filename extension, then it must be renamed 
        before it can be rotated.
        """
        print(f"{path}: '{Path(path).suffix.lower()}'")
        if Path(path).suffix.lower() in [".png", ".jpg", ".jpeg"]:
            return True
        else:
            return False
    
    def rotate_image():
        wallet = str(Path(filepath).parent).lstrip("surveyscans/")
        cwd = settings.SCANS_ROOT / wallet
        print(f"ROTATE \n{cwd=} \n{filename=}")
        mogrify = settings.MOGRIFY
        rot = subprocess.run(
            [mogrify, "-rotate", "90", filename], cwd=cwd, capture_output=True, text=True
        )
        msgdata = (
            rot.stderr
            + "\n"
            + rot.stdout
            + "\nreturn code: "
            + str(rot.returncode)
        )
        message = f'! - ROTATE - Success: rotated this file {filename}.' + msgdata
        print(message)
        # DataIssue.objects.create(parser="mogrify", message=message)
 
        if rot.returncode != 0:
            msgdata = (
                "Ask a nerd to fix this.\n\n"
                + rot.stderr
                + "\n\n"
                + rot.stdout
                + "\n\nreturn code: "
                + str(rot.returncode)
            )
            message = (
                f"! - ROTATE - CANNOT blurk for this file {filename}. \n"
                + msgdata
            )
            print(message)
            DataIssue.objects.create(parser="mogrify", message=message)

        return simple_get()
        
    def simple_get():
        form = ExpofileRenameForm()
        return render(
            request,
            "renameform.html",
            {
                "form": form,
                "filepath": filepath,
                "filename": filename,
                "filesize": filesize,
                "files": files,
                "walletpath": walletpath,
                "wallet": wallet,
                "notpics": notpics,
                "rotatable": rotatable,
            },
        )
        
    if filepath:
        # using EXPOFILES not SCANS_ROOT in case we want to extend this to other parts of the system
        actualpath = Path(settings.EXPOFILES) / Path(filepath)
    else:
        message = f'\n File to rename not specified "{filepath}"'
        print(message)
        return render(request, "errors/generic.html", {"message": message})
    
    if not actualpath.is_file():
        message = f'\n File not found when attempting rename "{filepath}"'
        print(message)
        return render(request, "errors/generic.html", {"message": message})
    else:
        filename = Path(filepath).name
        walletpath = Path(filepath).parent
        wallet = Path(walletpath).name
        folder = actualpath.parent
        filesize = f"{actualpath.stat().st_size:,}"
        rotatable= is_rotatable(filename)
 

    if not actualpath.is_relative_to(Path(settings.SCANS_ROOT)):
        message = f'\n Can only do rename within wallets (expofiles/surveyscans/) currently, sorry. "{actualpath}" '
        print(message)
        return render(request, "errors/generic.html", {"message": message})
        
    files = []
    dirs = []
    notpics =[]
    dirpath = actualpath.parent
    print(f'! - FORM rename expofile - start \n{filepath=} \n{dirpath=} \n{walletpath=}')
    if dirpath.is_dir():
        try:
            for f in dirpath.iterdir():
                if f.is_dir():
                    for d in f.iterdir():
                        dirs.append(f"{f.name}/{d.name}")
                if f.is_file():
                    if is_rotatable(f.name): # should allow all images here which can be thumsized, not just rotatables. e.g. PDF
                        files.append(f.name)
                    else:
                        notpics.append(f.name)     
        except FileNotFoundError:
            files.append(
                "(Error. There should be at least one filename visible here. Try refresh.)"
            )
    if request.method == "GET":
        return simple_get()
        
    elif request.method == "POST":
        form = ExpofileRenameForm(request.POST)
        if not form.is_valid():
            message = f'Invalid form response for file renaming "{request.POST}"'
            print(message)
            return render(request, "errors/generic.html", {"message": message})

        if "rotate" in request.POST:
            return rotate_image()
            
        if "rename" in request.POST:
            if "renametoname" not in request.POST:
                print("renametoname not in request.POST")
                # blank filename passed it, so just treat as another GET
                return simple_get()  


            renameto = sanitize_name(request.POST["renametoname"])  
            if (folder / renameto).is_file() or (folder / renameto).is_dir():
                rename_bad = renameto
                message = f'\n Cannot rename to an existing file or folder. "{filename}" -> "{(folder / renameto)}"'
                print(message)
                return render(
                    request,
                    "renameform.html",
                    {
                        "form": form,
                        "filepath": filepath,
                        "filename": filename,
                        "filesize": filesize,
                        "files": files,
                        "walletpath": walletpath,
                        "wallet": wallet,
                        "notpics": notpics,
                        "rename_bad": rename_bad,
                    },
                )

            actualpath.rename((folder / renameto))
            message = f'\n RENAMED "{filename}" -> "{(folder / renameto)}"'
            print(message)
            walletid  = actualpath.relative_to(Path(settings.SCANS_ROOT)).parent.stem.replace("#",":")
            print(walletid)
            return redirect(f'/survey_scans/{walletid}/')
            
    else: # not GET or POST
        print("UNRECOGNIZED action")
        return simple_get()
 
@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.
    
    Pending generic file renaming capability more generally.
    """
    year = current_expo()
    # 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 = sanitize_name(request.POST["photographer"])
                try:
                    (yearpath / newphotographer).mkdir(exist_ok=True)
                except:
                    message = f'\n !! Permissions failure ?! 0 attempting to mkdir "{(yearpath / newphotographer)}"'
                    print(message)
                    return render(request, "errors/generic.html", {"message": message})

        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 = sanitize_name(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 ?! 1 attempting to save "{f.name}" in "{dirpath}" {renameto=}'
                                )
                                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 ?! 2 attempting to save "{f.name}" in "{dirpath}" {renameto=}'
                                )
                                if "saved_filename" in locals():
                                    if saved_filename.is_file():
                                        actual_saved.append(saved_filename)
                                        filesaved = True
                    else:  # multiple 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 ?! 3 attempting to save "{f.name}" in "{dirpath}" {renameto=}'
                                )
                                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,
    but this won't work on Tunnel files as Tunnel does not produce exactly valid xml

    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")
            savepath = Path(settings.DRAWINGS_DATA, folder)
            fs = FileSystemStorage(savepath)

            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}" in "{savepath}". 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 {f.name}. 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,
        },
    )