"""Views for the create overview part"""

from tempfile import NamedTemporaryFile

from pyramid.httpexceptions import HTTPFound
from pyramid.view import view_config
from pyramid_mailer.message import Attachment, Message

from ..budget import parse_budget_file
from ..exceptions import BudgetParserError, SuperXParserError
from ..helpers import find_budget_file, find_recipients, get_sheet_of_file
from ..overview import create_overview
from ..superx import parse_exported_file
from . import XLSX_CONTENT_TYPE, Root

MAIL_MESSAGE_BODY = """Hallo an Alle,

anbei ist eine aktuelle Übersicht unserer Verbrauchsmittel-Budgets.

Frohes Bestellen!

--
Dies ist eine automatisch generierte Email,
bei Fragen bitte an Holgi wenden

"""


def _map_from_form_data(request, prefix):
    if not prefix.endswith("-"):
        prefix = f"{prefix}-"
    result = {}
    for key, value in request.POST.items():
        if key.startswith(prefix):
            row_str = key.split("-")[-1]
            row = int(row_str)
            try:
                as_number = float(value)
            except ValueError:
                as_number = 0
            result[row] = as_number
    return result


@view_config(
    context=Root,
    request_method="GET",
    renderer="superx_budget:pyramid/templates/start.jinja2",
    permission="view",
)
def index(context, request):  # noqa: ARG001
    return {}


@view_config(
    context=Root,
    request_method="POST",
    renderer="superx_budget:pyramid/templates/overview.jinja2",
    permission="view",
)
def superx_upload(context, request):  # noqa: ARG001
    upload = request.POST.get("superx")

    if upload == b"" or not upload.filename.endswith(".xlsx"):
        request.session.flash("No Excel file uploaded.", "error")
        return HTTPFound("/")

    try:
        superx_export = parse_exported_file(upload.file)
    except SuperXParserError:
        request.session.flash(
            "File does not appear to be the required SuperX export.", "error"
        )
        return HTTPFound("/")

    budget_file = find_budget_file(
        request.budgets_dir, superx_export.account_year
    )
    if budget_file is None:
        request.session.flash(
            f"No budget file for year {superx_export.account_year} found.",
            "error",
        )
        return HTTPFound("/")

    try:
        budget_data = parse_budget_file(budget_file)
    except BudgetParserError:
        request.session.flash(
            "Budget File does not appear to be in the required format.",
            "error",
        )
        return HTTPFound("/")

    overview_map = create_overview(budget_data, superx_export)
    overview = sorted(overview_map.values(), key=lambda i: i.row)

    if any(not (item.found) for item in overview):
        request.session.flash(
            (
                "Some projects in the budget template were not in the SuperX "
                "export. Please adjust their expenses manually."
            ),
            "info",
        )

    recipients = find_recipients(request.budgets_dir)

    return {
        "account_year": superx_export.account_year,
        "export_date": superx_export.export_date.strftime("%Y-%m-%d"),
        "overview": overview,
        "template": budget_file.name,
        "recipients": recipients,
    }


@view_config(
    context=Root,
    name="send",
    request_method="POST",
    renderer="superx_budget:pyramid/templates/sent.jinja2",
    permission="view",
)
def send_overview(context, request):  # noqa: ARG001
    export_date = request.POST.get("export_date").strip()
    tmp_recipients = request.POST.get("recipients").strip()
    recipients = tmp_recipients.splitlines()
    budget_template = request.POST.get("template")
    budget_file = request.budgets_dir / budget_template

    budgets = _map_from_form_data(request, "budget-")
    expenses = _map_from_form_data(request, "expense-")
    available = {k: (v - expenses[k]) for k, v in budgets.items()}

    # sanity check
    if (
        not export_date
        or not recipients
        or not expenses
        or not available
        or not budget_file.is_file()
    ):
        request.session.flash(
            "There was an error with your submisssion, please try again.",
            "error",
        )
        return HTTPFound("/")

    sheet = get_sheet_of_file(budget_file)
    for row, value in expenses.items():
        cell = f"G{row}"
        sheet[cell] = value
    for row, value in available.items():
        cell = f"H{row}"
        sheet[cell] = value

    budget_year = budget_file.stem.split("-")[-1]
    message = Message(
        subject=f"Budget Übersicht {budget_year}, Stand {export_date}",
        sender="cpiserver@imtek.uni-freiburg.de",
        recipients=recipients,
        body=MAIL_MESSAGE_BODY,
    )

    xls_name = f"{export_date}-Budget-Overview-{budget_year}.xlsx"
    with NamedTemporaryFile() as tmp:
        sheet._parent.save(tmp.name)  # noqa: SLF001
        tmp.seek(0)
        attachment = Attachment(xls_name, XLSX_CONTENT_TYPE, tmp)
        message.attach(attachment)
        request.mailer.send_immediately(message, fail_silently=False)

    return {"recipients": recipients, "xls_name": xls_name}