import csv
from datetime import date

from django.contrib.auth.decorators import login_required
from django.http import HttpResponse
from django.shortcuts import render, get_object_or_404

from .models import Entreprise
from . import services


def _entreprise_courante(request):
    eid = request.GET.get("entreprise")
    qs = Entreprise.objects.all()
    if eid:
        return get_object_or_404(Entreprise, pk=eid)
    return qs.first()


@login_required
def dashboard(request):
    entreprise = _entreprise_courante(request)
    if entreprise is None:
        return render(request, "compta/dashboard.html", {"entreprise": None})

    annee = int(request.GET.get("annee", date.today().year))
    ctx = services.synthese(entreprise, annee)
    ctx.update({
        "entreprises": Entreprise.objects.all(),
        "annees": services.annees_disponibles(entreprise) or [annee],
        "mois_labels": ["Jan", "Fév", "Mar", "Avr", "Mai", "Juin",
                        "Juil", "Août", "Sep", "Oct", "Nov", "Déc"],
        "ca_mensuel_json": [float(v) for v in ctx["ca_mensuel"]],
    })
    return render(request, "compta/dashboard.html", ctx)


def _csv_response(filename):
    resp = HttpResponse(content_type="text/csv; charset=utf-8")
    resp["Content-Disposition"] = f'attachment; filename="{filename}"'
    resp.write("")  # BOM pour Excel
    return resp


@login_required
def export_ventes(request):
    entreprise = _entreprise_courante(request)
    annee = int(request.GET.get("annee", date.today().year))
    resp = _csv_response(f"ventes_{annee}.csv")
    w = csv.writer(resp, delimiter=";")
    w.writerow(["Numero", "Client", "Activite", "Date emission",
                "Date encaissement", "Statut", "HT", "TVA", "TTC"])
    for f in services.factures_encaissees(entreprise, annee).select_related("client"):
        w.writerow([f.numero, f.client.nom, f.get_activite_display(),
                    f.date_emission, f.date_encaissement, f.get_statut_display(),
                    f.montant_ht, f.montant_tva, f.montant_ttc])
    return resp


@login_required
def export_tva(request):
    entreprise = _entreprise_courante(request)
    annee = int(request.GET.get("annee", date.today().year))
    s = services.synthese(entreprise, annee)
    resp = _csv_response(f"tva_{annee}.csv")
    w = csv.writer(resp, delimiter=";")
    w.writerow(["Annee", "TVA collectee", "TVA deductible", "TVA a reverser"])
    w.writerow([annee, s["tva_collectee"], s["tva_deductible"],
                s["tva_a_reverser"]])
    return resp


@login_required
def export_urssaf(request):
    entreprise = _entreprise_courante(request)
    annee = int(request.GET.get("annee", date.today().year))
    s = services.synthese(entreprise, annee)
    resp = _csv_response(f"urssaf_{annee}.csv")
    w = csv.writer(resp, delimiter=";")
    w.writerow(["Annee", "Activite", "CA HT", "Taux URSSAF", "Cotisations",
                "Taux VL", "Versement liberatoire", "Abattement",
                "Revenu imposable"])
    for l in s["lignes_activite"]:
        w.writerow([annee, l["label"], l["ca_ht"], l["taux_urssaf"],
                    l["cotisations"], l["taux_vl"], l["versement_liberatoire"],
                    l["abattement_fiscal"], l["revenu_imposable"]])
    w.writerow([annee, "TOTAL", s["ca_ht"], "", s["cotisations_urssaf"],
                "", s["versement_liberatoire"], "", s["revenu_imposable"]])
    return resp