use decky_api::{StorePluginQuery, StorePluginQuerySortColumn, StorePluginQuerySortDirection};

use super::IQueryHandler;

pub struct StandardPostRetrievalSort;

impl IQueryHandler for StandardPostRetrievalSort {
    fn filter(&self, query: &str, mut plugins: decky_api::StorePluginList) -> decky_api::StorePluginList {
        log::debug!("StandardPostRetrievalSort::filter got query string `{}`", query);
        let query: StorePluginQuery = match serde_urlencoded::from_str(query) {
            Ok(q) => q,
            Err(e) => {
                log::error!("Failed to parse query string {}: {}", query, e);
                Default::default()
            }
        };
        match (query.sort_by, query.sort_direction) {
            (None, _) => plugins,
            (Some(StorePluginQuerySortColumn::Name), direction) => {
                plugins.sort_by_key(|p| p.name.to_lowercase());
                match direction {
                    None | Some(StorePluginQuerySortDirection::Ascending) => {},
                    Some(StorePluginQuerySortDirection::Descending) => plugins.reverse(),
                }
                plugins
            },
            (Some(StorePluginQuerySortColumn::Date), direction) => {
                plugins.sort_by_key(
                    |p| p.versions.iter()
                        .max_by_key(
                            |v| v.created.unwrap_or_default())
                        .map(|v| v.created.unwrap_or_default())
                );
                match direction {
                    None | Some(StorePluginQuerySortDirection::Ascending) => {},
                    Some(StorePluginQuerySortDirection::Descending) => plugins.reverse(),
                }
                plugins
            },
            (Some(StorePluginQuerySortColumn::Downloads), direction) => {
                plugins.sort_by_key(|p| p.versions.iter().map(|v| v.downloads.unwrap_or(0)).sum::<u64>());
                match direction {
                    None | Some(StorePluginQuerySortDirection::Ascending) => {},
                    Some(StorePluginQuerySortDirection::Descending) => plugins.reverse(),
                }
                plugins
            },
        }
    }

    fn supported_params(&self, query: &str) -> String {
        match serde_urlencoded::from_str::<StorePluginQuery>(query) {
            Ok(q) => serde_urlencoded::to_string(&q).unwrap_or_default(),
            Err(_) => "".to_owned()
        }
    }

    fn descriptor(&self) -> String {
        "standard_post_retrieval".to_owned()
    }
}