from datetime import datetime
import distinctipy
from django.contrib import admin

from util import next_payday, rgb_tuple_to_hex

from .admin_base import AdminBase, DeletedListFilter, DeletableAdminForm
from .models import Expense, ExpenseCategory, Timesheet, TimesheetRate, Vendor
from django import forms
from django.utils import timezone
from import_export import resources
from import_export.admin import ImportExportModelAdmin
from admincharts.admin import AdminChartMixin
from admincharts.utils import months_between_dates
from djmoney.contrib.exchange.models import convert_money


class VendorAdminForm(DeletableAdminForm):
    class Meta:
        model = Vendor
        fields = "__all__"


@admin.register(Vendor)
class VendorAdmin(AdminBase):
    list_display = (
        "name",
        "description",
    )
    search_fields = ("name",)
    form = VendorAdminForm


class TimesheetRateAdminForm(DeletableAdminForm):
    class Meta:
        model = TimesheetRate
        fields = "__all__"


@admin.register(TimesheetRate)
class TimesheetRateAdmin(AdminBase):
    list_display = (
        "rate",
        "description",
        "default_rate",
    )
    form = TimesheetRateAdminForm


class TimesheetResource(resources.ModelResource):
    class Meta:
        model = Timesheet


class TimesheetAdminForm(DeletableAdminForm):
    class Meta:
        model = Timesheet
        fields = "__all__"

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        if not self.instance.shift_start:
            self.initial["shift_start"] = timezone.now()
        self.fields["rate"].initial = forms.ModelChoiceField(
            queryset=TimesheetRate.objects.all(),
            required=True,
            widget=forms.Select,
            label="Select Another Table",
        )
        self.initial["rate"] = TimesheetRate.objects.filter(default_rate=True).first()


@admin.register(Timesheet)
class TimesheetAdmin(AdminBase, AdminChartMixin, ImportExportModelAdmin):
    resource_classes = [TimesheetResource]
    form = TimesheetAdminForm
    fields = (
        ("shift_start", "shift_end"),
        ("break_start", "break_end"),
        ("rate"),
        ("submitted"),
    )

    list_display = (
        "shift_start",
        "worked_hours",
        "worked_decimal",
        "total",
        "_rules",
        "submitted",
        "rate",
        # "shift_hours",
        # "break_hours",
    )
    list_filter = ("shift_start", ("deleted", DeletedListFilter))
    ordering = ("-shift_start", "-deleted")
    readonly_fields = ("deleted",)

    def submit(self, request, queryset):
        if queryset.exists():
            for item in queryset:
                if not item.submitted:
                    item.submitted = timezone.now()
                    item.save()

    def changelist_view(self, request, extra_context=None):
        payday = next_payday()
        extra_context = {
            "title": f"Next timesheet due {payday.strftime('%B %-d')} (in {(payday - datetime.now()).days + 1} days)."
        }
        return super().changelist_view(request, extra_context=extra_context)

    submit.short_description = "Mark as submitted"

    actions = [submit, AdminBase.delete_selected, AdminBase.restore_deleted]

    def get_list_chart_data(self, queryset):
        if not queryset:
            return {}

        # Cannot reorder the queryset at this point
        earliest = min([x.shift_start for x in queryset]).replace(day=1)

        expenses_in_range = Expense.objects.filter(
            date__range=[earliest, timezone.now()], deleted=False
        )

        labels = []
        totals = []
        expenses_total = []
        for b in months_between_dates(earliest, timezone.now()):
            labels.append(b.strftime("%b %Y"))
            totals.append(
                sum(
                    [
                        convert_money(x.total, "AUD").amount
                        for x in queryset
                        if x.shift_start.year == b.year
                        and x.shift_start.month == b.month
                    ]
                )
            )
            expenses_total.append(
                sum(
                    [
                        convert_money(x.price, "AUD").amount
                        for x in expenses_in_range
                        if x.date.year == b.year and x.date.month == b.month
                    ]
                )
            )

        return {
            "labels": labels,
            "datasets": [
                {
                    "label": "Income (Pre-tax)",
                    "data": totals,
                    "backgroundColor": "#79aec8",
                },
                {
                    "label": "Expenditure",
                    "data": expenses_total,
                    "backgroundColor": "#865137",
                },
            ],
        }


class ExpenseAdminForm(DeletableAdminForm):
    class Meta:
        model = Expense
        fields = "__all__"


@admin.register(Expense)
class ExpenseAdmin(AdminBase, AdminChartMixin, ImportExportModelAdmin):
    form = ExpenseAdminForm

    autocomplete_fields = ("vendor", "category")
    list_display = ("date", "price", "description", "category", "vendor")
    list_filter = ("date", ("deleted", DeletedListFilter), "category", "vendor")
    ordering = ("-date", "-deleted")
    readonly_fields = ("deleted",)

    def get_changeform_initial_data(self, request):
        initial = super().get_changeform_initial_data(request)
        initial["date"] = timezone.now().date()
        return initial

    list_chart_type = "bar"
    list_chart_data = {}
    list_chart_options = {"aspectRatio": 6}
    list_chart_config = None  # Override the combined settings

    def get_list_chart_data(self, queryset):
        if not queryset:
            return {}

        # Cannot reorder the queryset at this point
        earliest = min([x.date for x in queryset]).replace(day=1)
        timesheets = Timesheet.objects.filter(
            shift_start__range=[earliest, timezone.now()]
        )

        labels = []
        totals = []
        expenses_total = []
        expense_types = set([x.category.name for x in queryset])
        colors = distinctipy.get_colors(len(expense_types), pastel_factor=0.2, rng=69)
        expenses = {}
        i = 0
        for k in expense_types:
            expenses.update(
                {
                    k: {
                        "label": k,
                        "data": [],
                        "backgroundColor": rgb_tuple_to_hex(colors[i]),
                    }
                }
            )
            i += 1

        for b in months_between_dates(earliest, timezone.now().date()):
            labels.append(b.strftime("%b %Y"))
            totals.append(
                sum(
                    [
                        convert_money(x.total, "AUD").amount
                        for x in timesheets
                        if x.shift_start.year == b.year
                        and x.shift_start.month == b.month  # noqa
                    ]
                )
            )
            expenses_total.append(0)
            for k in expenses.keys():
                expenses[k]["data"].append(0)
            for x in queryset:
                if x.date.year == b.year and x.date.month == b.month:
                    expenses_total[-1] += convert_money(x.price, "AUD").amount
                    expenses[x.category.name]["data"][-1] += convert_money(
                        x.price, "AUD"
                    ).amount

        return {
            "labels": labels,
            "datasets": [
                {
                    "label": "Income (Pre-tax)",
                    "data": totals,
                    "backgroundColor": "#79aec8",
                },
                {
                    "label": "Expenditure",
                    "data": expenses_total,
                    "backgroundColor": "#865137",
                },
            ]
            + list(expenses.values()),  # noqa
        }


@admin.register(ExpenseCategory)
class ExpenseCategoryAdmin(AdminBase):
    search_fields = ("name",)