// rocie - An enterprise grocery management system - Web app
//
// Copyright (C) 2026 Benedikt Peetz <benedikt.peetz@b-peetz.de>
// SPDX-License-Identifier: GPL-3.0-or-later
//
// This file is part of Rocie.
//
// You should have received a copy of the License along with this program.
// If not, see <https://www.gnu.org/licenses/gpl-3.0.txt>.

use std::{convert::Infallible, iter, str::FromStr};

use leptos::{
    IntoView, component,
    prelude::{Get, Show, signal},
    task::spawn_local,
    view,
};
use leptos_router::{NavigateOptions, hooks::use_navigate};
use rocie_client::models::{ProductParentId, ProductStub, UnitPropertyId};
use rocie_macros::Form;
use uuid::Uuid;

use crate::{
    api::{
        get_config, product_parents_wrapped, register_product_external_wrapped,
        unit_properties_wrapped,
    },
    components::{
        async_fetch::AsyncResource, banner::Banner, catch_errors::CatchErrors,
        login_wall::LoginWall, site_header::SiteHeader,
    },
};

pub(crate) struct OptionalString(pub(crate) Option<String>);

impl FromStr for OptionalString {
    type Err = Infallible;

    fn from_str(s: &str) -> Result<Self, Self::Err> {
        if s.is_empty() {
            Ok(Self(None))
        } else {
            Ok(Self(Some(s.to_owned())))
        }
    }
}

struct OptionalParentId(Option<ProductParentId>);

impl FromStr for OptionalParentId {
    type Err = uuid::Error;

    fn from_str(s: &str) -> Result<Self, Self::Err> {
        if s.is_empty() {
            Ok(Self(None))
        } else {
            Ok(Self(Some(ProductParentId { value: s.parse()? })))
        }
    }
}

#[component]
pub fn CreateProduct() -> impl IntoView {
    let (error_message, error_message_set) = signal(None);

    view! {
        <CatchErrors>
            <LoginWall back=move || "/create-product".to_owned()>
                <SiteHeader logo=icondata_io::IoArrowBack back_location="/" name="Create Product" />

                <Show when=move || error_message.get().is_some()>
                    <Banner text=move || error_message.get().expect("Is some") />
                </Show>

                {
                    Form! {
                        on_submit = |product_name, product_description, unit_property_id, parent| {
                        let config = get_config!();
                        let navigate = use_navigate();

                        spawn_local(async move {
                            match register_product_external_wrapped(&config, ProductStub {
                                    description: product_description.0.map(|d| d.trim().to_owned()),
                                    name: product_name.trim().to_owned(),
                                    parent: parent.0,
                                    unit_property: UnitPropertyId { value: unit_property_id },
                                }
                            ).await {
                                Ok(_id) => {
                                    navigate("/create-product", NavigateOptions::default());
                                }
                                Err(err) => error_message_set.set(Some(format!("Failed to create product: {err}"))),
                            }
                        });
                    };

                <Input
                    name=product_name,
                    rust_type=String,
                    html_type="text",
                    label="Product Name",
                />

                <Input
                    name=product_description,
                    rust_type=OptionalString,
                    html_type="text",
                    label="Product Description"
                />

                <Select
                    name=parent,
                    rust_type=OptionalParentId,
                    label="Parent",
                    options=AsyncResource! {
                        () -> Result<Vec<(String, String)>, leptos::error::Error> {
                            let parents = product_parents_wrapped().await?;

                            Ok(
                                iter::once(("No parent".to_owned(), String::new()))
                                    .chain(
                                        parents
                                            .into_iter()
                                            .map(|prop| (prop.name, prop.id.to_string()))
                                    )
                                    .collect()
                            )
                        }
                    },
                />

                <Select
                    name=unit_property_id,
                    rust_type=Uuid,
                    label="Unit property",
                    options=AsyncResource! {
                        () -> Result<Vec<(String, String)>, leptos::error::Error> {
                            let unit_properties = unit_properties_wrapped().await?;

                            Ok(
                                unit_properties
                                    .into_iter()
                                    .map(|prop| (prop.name, prop.id.to_string()))
                                    .collect()
                            )
                        }
                    },
                />
                    }
                }
            </LoginWall>
        </CatchErrors>
    }
}