import os, stat
import re
import datetime
from pathlib import Path
from urllib.parse import urljoin, unquote as urlunquote
from urllib.request import urlopen

from django.conf import settings
from django.shortcuts import render
from django.http import HttpResponse

from troggle.core.models.survex import Wallet, SingleScan, SurvexBlock
from troggle.core.models.caves import GetCaveLookup
from troggle.core.views.expo import getmimetype
#import parsers.surveys

'''one of these views serves files as binary blobs, and simply set the mime type based on the file extension,
as does the urls.py dispatcher which sends them here. Here they should actually have the filetype checked 
by looking inside the file before being served.

need to check if inavlid query string is invalid, or produces multiple replies
and render a user-friendly error page.
'''

def populatewallet(w):
    '''Copy survex data here just for display, not permanently
    '''
    # {% for personrole in wallet.survexblock.survexpersonrole_set.all %}
        # {% if personrole.personexpedition %}
            # <a href="{{personrole.personexpedition.get_absolute_url}}">{{personrole.personname}}</a>
        # {% else %}
            # {{personrole.personname}}
        # {% endif %}
    # {% endfor %}

    survexpeople = []
    blocks = SurvexBlock.objects.filter(scanswallet = w)
    for b in blocks:
        for personrole in b.survexpersonrole_set.all(): 
            survexpeople.append(personrole.personname)
        w.people = list(set(survexpeople)) # remove duplicates

def datewallet(w, earliest):
    blocks = SurvexBlock.objects.filter(scanswallet = w)
    for b in blocks:    
        if b.date < earliest:
            earliest = b.date    
    w.date = earliest
    
def caveifywallet(w):
    print('*')
    blocks = SurvexBlock.objects.filter(scanswallet = w)
    for b in blocks:    
        # NB b.cave is not populated by parser. Use b.survexfile.cave instead, or we could parse b.survexpath
        if b.survexfile.cave:
            w.cave  = b.survexfile.cave # just gets the last one, randomly
            print(w.cave)


def walletslistyear(request, year):
    '''Page which displays a list of all the wallets in a specific year - TO BE WRITTEN
    '''
    if year < 1976 or year > 2050:
        return render(request, 'errors/generic.html', {'message': 'Year out of range. Must be between 1976 and 2050'})   
    else:
        year = str(year)
    return render(request, 'errors/generic.html', {'message': 'This page logic not implemented yet'})   


def cavewallets(request, caveid):
    '''Returns all the wallets for just one cave
    '''
    
    Gcavelookup = GetCaveLookup()
    if caveid in Gcavelookup:
        cave = Gcavelookup[caveid]
    else:
        return render(request,'errors/badslug.html', {'badslug': caveid})

    earliest = datetime.datetime.now().date()

    # remove duplication. SOrting is done in the template
    wallets = set(Wallet.objects.filter(survexblock__survexfile__cave=cave)) # NB a filtered set
    manywallets = list(wallets)


    for w in manywallets:
        wp = w.people()
        if not wp: # an -empty list
            populatewallet(w)
        else:
            if len(wp) == 1:
                nobody = wp[0].lower()
                if  nobody == 'unknown' or nobody == 'nobody' or nobody == ' ':
                    populatewallet(w)
        
        if not w.date():
            datewallet(w, earliest)
            
        c = w.cave()
        
        if not c:
            caveifywallet(w)
 
    return render(request, 'cavewallets.html', { 'manywallets':manywallets, 'settings': settings, 'cave': cave})

def oldwallet(request, path):
    '''Now called only for non-standard wallet structures for pre-2000 wallets
    '''
    # print([ s.walletname  for s in Wallet.objects.all() ])
    print(f'! - oldwallet path:{path}')
    try:
        wallet = Wallet.objects.get(walletname=urlunquote(path))  
        return render(request, 'wallet_old.html', { 'wallet':wallet, 'settings': settings })
    except:
        message = f'Scan folder error or not found \'{path}\' .'
        return render(request, 'errors/generic.html', {'message': message})   

def walletindex(request, path):
    '''All years: special 'wallet' for scanned index pages
    '''
    # print([ s.walletname  for s in Wallet.objects.all() ])
    print(f'! - walletindex path:{path}')
    try:
        wallet = Wallet.objects.get(walletname=urlunquote(path))  
        return render(request, 'walletindex.html', { 'wallet':wallet, 'settings': settings })
    except:
        message = f'Scan folder error or not found \'{path}\' .'
        return render(request, 'errors/generic.html', {'message': message})   

def scansingle(request, path, file):
    '''sends a single binary file to the user for display - browser decides how using mimetype
    '''

    try:
        wallet = Wallet.objects.get(walletname=urlunquote(path)) 
        singlescan = SingleScan.objects.get(wallet=wallet, name=file)
        print(" - scansingle {}:{}:{}:".format(path, file, getmimetype(file)))
        return HttpResponse(content=open(singlescan.ffile,"rb"), content_type=getmimetype(file)) # any type of image
    except:
        message = f'Scan folder or scan item error or not found \'{path}\'  and \'{file}\'.'
        return render(request, 'errors/generic.html', {'message': message})   


def allscans(request):
    '''Returns all the wallets in the system, we would like to use
    the Django queryset SQL optimisation https://docs.djangoproject.com/en/3.2/ref/models/querysets/#prefetch-related
    to get the related singlescan and survexblock objects but that requires rewriting this to do the query on those, not on
    the wallets
    '''
    manywallets = Wallet.objects.all() # NB all of them
    # manywallets = Wallet.objects.all().prefetch_related('singlescan') fails as the link is defined on 'singlescan' not on 'wallet'
    return render(request, 'manywallets.html', { 'manywallets':manywallets, 'settings': settings })