from django import forms
from django.contrib.auth import get_user_model, password_validation
from django.core.exceptions import ValidationError
from django.utils.translation import gettext_lazy as _

from .models import Claim, Project

User = get_user_model()

INPUT_CLASSES = "mt-1 block w-full rounded-lg border border-gray-300 bg-white px-3 py-2 text-sm text-gray-900 shadow-sm focus:border-indigo-500 focus:ring-2 focus:ring-indigo-500"
TEXTAREA_CLASSES = "mt-1 block w-full rounded-lg border border-gray-300 bg-white px-3 py-2 text-sm text-gray-900 shadow-sm focus:border-indigo-500 focus:ring-2 focus:ring-indigo-500"
SELECT_CLASSES = "mt-1 block w-full rounded-lg border border-gray-300 bg-white px-3 py-2 text-sm text-gray-900 shadow-sm focus:border-indigo-500 focus:ring-2 focus:ring-indigo-500"
FILE_CLASSES = "mt-1 block w-full text-sm text-gray-700 file:mr-4 file:rounded-md file:border-0 file:bg-indigo-600 file:px-4 file:py-2 file:text-sm file:font-medium file:text-white hover:file:bg-indigo-500"


class ClaimantForm(forms.Form):
    full_name = forms.CharField(
        max_length=255,
        label=_("Namn"),
        widget=forms.TextInput(attrs={"class": INPUT_CLASSES}),
    )
    email = forms.EmailField(
        label=_("E-post"),
        widget=forms.EmailInput(attrs={"class": INPUT_CLASSES}),
    )
    account_number = forms.CharField(
        max_length=50,
        label=_("Kontonummer"),
        widget=forms.TextInput(attrs={"class": INPUT_CLASSES}),
    )


class ClaimLineForm(forms.ModelForm):
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        if not self.is_bound:
            self.fields["currency"].initial = Claim.Currency.SEK
        self.fields["project"].queryset = Project.objects.filter(is_active=True).order_by("name")
        self.fields["project"].required = False
        self.fields["project"].widget.attrs.update({"class": SELECT_CLASSES})
        self.fields["currency"].widget.attrs.update({"class": SELECT_CLASSES})
        self.fields["amount"].widget.attrs.update({"class": INPUT_CLASSES})
        self.fields["receipt"].widget.attrs.update({"class": FILE_CLASSES})

    class Meta:
        model = Claim
        fields = ["description", "amount", "currency", "project", "receipt"]
        labels = {
            "description": _("Beskrivning"),
            "amount": _("Belopp"),
            "currency": _("Valuta"),
            "project": _("Evenemang/Projekt"),
            "receipt": _("Kvitto"),
        }
        widgets = {
            "description": forms.Textarea(attrs={"rows": 3, "class": TEXTAREA_CLASSES}),
        }


class ClaimDecisionForm(forms.Form):
    ACTION_APPROVE = "approve"
    ACTION_REJECT = "reject"
    ACTION_CHOICES = (
        (ACTION_APPROVE, _("Godkänn")),
        (ACTION_REJECT, _("Neka")),
    )

    claim_id = forms.IntegerField(widget=forms.HiddenInput)
    action = forms.ChoiceField(choices=ACTION_CHOICES)
    decision_note = forms.CharField(
        required=False,
        widget=forms.Textarea(attrs={"rows": 2, "placeholder": _("Kommentar")}),
    )

    def clean(self):
        cleaned = super().clean()
        action = cleaned.get("action")
        note = cleaned.get("decision_note", "").strip()
        if action == self.ACTION_REJECT and not note:
            self.add_error("decision_note", _("Kommentar krävs när du nekar ett utlägg."))
        return cleaned


class UserManagementForm(forms.Form):
    username = forms.CharField(max_length=150, label=_("Användarnamn"))
    email = forms.EmailField(required=False, label=_("E-post"))
    first_name = forms.CharField(max_length=150, required=False, label=_("Förnamn"))
    last_name = forms.CharField(max_length=150, required=False, label=_("Efternamn"))
    password1 = forms.CharField(widget=forms.PasswordInput, label=_("Lösenord"))
    password2 = forms.CharField(widget=forms.PasswordInput, label=_("Bekräfta lösenord"))
    is_staff = forms.BooleanField(required=False, initial=True, label=_("Administratör (staff)"))
    grant_view = forms.BooleanField(required=False, initial=True, label=_("Ge behörighet att se utlägg"))
    grant_change = forms.BooleanField(required=False, initial=True, label=_("Ge behörighet att besluta utlägg"))

    def clean_username(self):
        username = self.cleaned_data["username"]
        if User.objects.filter(username=username).exists():
            raise forms.ValidationError(_("Användarnamnet är upptaget."))
        return username

    def clean(self):
        cleaned = super().clean()
        if cleaned.get("password1") != cleaned.get("password2"):
            self.add_error("password2", _("Lösenorden matchar inte."))
        password = cleaned.get("password1")
        if password:
            temp_user = User(
                username=cleaned.get("username", ""),
                email=cleaned.get("email", ""),
                first_name=cleaned.get("first_name", ""),
                last_name=cleaned.get("last_name", ""),
            )
            try:
                password_validation.validate_password(password, temp_user)
            except ValidationError as exc:
                self.add_error("password1", exc)
        return cleaned


class UserPermissionForm(forms.Form):
    user_id = forms.IntegerField(widget=forms.HiddenInput)
    is_staff = forms.BooleanField(required=False, label=_("Admin/staff"))
    grant_view = forms.BooleanField(required=False, label=_("Får se utlägg"))
    grant_change = forms.BooleanField(required=False, label=_("Får besluta utlägg"))


class DeleteUserForm(forms.Form):
    user_id = forms.IntegerField(widget=forms.HiddenInput)