1use anyhow::{anyhow, Result};
  2use async_trait::async_trait;
  3use futures::StreamExt;
  4use gpui::AsyncAppContext;
  5use language::{LanguageServerName, LspAdapter, LspAdapterDelegate};
  6use lsp::LanguageServerBinary;
  7use node_runtime::NodeRuntime;
  8use project::project_settings::ProjectSettings;
  9use serde_json::Value;
 10use settings::Settings;
 11use smol::fs;
 12use std::{
 13    any::Any,
 14    ffi::OsString,
 15    path::{Path, PathBuf},
 16    sync::Arc,
 17};
 18use util::{maybe, ResultExt};
 19
 20const SERVER_NAME: &str = "elm-language-server";
 21const SERVER_PATH: &str = "node_modules/@elm-tooling/elm-language-server/out/node/index.js";
 22
 23fn server_binary_arguments(server_path: &Path) -> Vec<OsString> {
 24    vec![server_path.into(), "--stdio".into()]
 25}
 26
 27pub struct ElmLspAdapter {
 28    node: Arc<dyn NodeRuntime>,
 29}
 30
 31impl ElmLspAdapter {
 32    pub fn new(node: Arc<dyn NodeRuntime>) -> Self {
 33        ElmLspAdapter { node }
 34    }
 35}
 36
 37#[async_trait(?Send)]
 38impl LspAdapter for ElmLspAdapter {
 39    fn name(&self) -> LanguageServerName {
 40        LanguageServerName(SERVER_NAME.into())
 41    }
 42
 43    async fn fetch_latest_server_version(
 44        &self,
 45        _: &dyn LspAdapterDelegate,
 46    ) -> Result<Box<dyn 'static + Any + Send>> {
 47        Ok(Box::new(
 48            self.node
 49                .npm_package_latest_version("@elm-tooling/elm-language-server")
 50                .await?,
 51        ) as Box<_>)
 52    }
 53
 54    async fn fetch_server_binary(
 55        &self,
 56        latest_version: Box<dyn 'static + Send + Any>,
 57        container_dir: PathBuf,
 58        _: &dyn LspAdapterDelegate,
 59    ) -> Result<LanguageServerBinary> {
 60        let latest_version = latest_version.downcast::<String>().unwrap();
 61        let server_path = container_dir.join(SERVER_PATH);
 62        let package_name = "@elm-tooling/elm-language-server";
 63
 64        let should_install_language_server = self
 65            .node
 66            .should_install_npm_package(package_name, &server_path, &container_dir, &latest_version)
 67            .await;
 68
 69        if should_install_language_server {
 70            self.node
 71                .npm_install_packages(&container_dir, &[(package_name, latest_version.as_str())])
 72                .await?;
 73        }
 74
 75        Ok(LanguageServerBinary {
 76            path: self.node.binary_path().await?,
 77            env: None,
 78            arguments: server_binary_arguments(&server_path),
 79        })
 80    }
 81
 82    async fn cached_server_binary(
 83        &self,
 84        container_dir: PathBuf,
 85        _: &dyn LspAdapterDelegate,
 86    ) -> Option<LanguageServerBinary> {
 87        get_cached_server_binary(container_dir, &*self.node).await
 88    }
 89
 90    async fn installation_test_binary(
 91        &self,
 92        container_dir: PathBuf,
 93    ) -> Option<LanguageServerBinary> {
 94        get_cached_server_binary(container_dir, &*self.node).await
 95    }
 96
 97    async fn workspace_configuration(
 98        self: Arc<Self>,
 99        _: &Arc<dyn LspAdapterDelegate>,
100        cx: &mut AsyncAppContext,
101    ) -> Result<Value> {
102        // elm-language-server expects workspace didChangeConfiguration notification
103        // params to be the same as lsp initialization_options
104        let override_options = cx.update(|cx| {
105            ProjectSettings::get_global(cx)
106                .lsp
107                .get(SERVER_NAME)
108                .and_then(|s| s.initialization_options.clone())
109                .unwrap_or_default()
110        })?;
111
112        Ok(match override_options.clone().as_object_mut() {
113            Some(op) => {
114                // elm-language-server requests workspace configuration
115                // for the `elmLS` section, so we have to nest
116                // another copy of initialization_options there
117                op.insert("elmLS".into(), override_options);
118                serde_json::to_value(op).unwrap_or_default()
119            }
120            None => override_options,
121        })
122    }
123}
124
125async fn get_cached_server_binary(
126    container_dir: PathBuf,
127    node: &dyn NodeRuntime,
128) -> Option<LanguageServerBinary> {
129    maybe!(async {
130        let mut last_version_dir = None;
131        let mut entries = fs::read_dir(&container_dir).await?;
132        while let Some(entry) = entries.next().await {
133            let entry = entry?;
134            if entry.file_type().await?.is_dir() {
135                last_version_dir = Some(entry.path());
136            }
137        }
138        let last_version_dir = last_version_dir.ok_or_else(|| anyhow!("no cached binary"))?;
139        let server_path = last_version_dir.join(SERVER_PATH);
140        if server_path.exists() {
141            Ok(LanguageServerBinary {
142                path: node.binary_path().await?,
143                env: None,
144                arguments: server_binary_arguments(&server_path),
145            })
146        } else {
147            Err(anyhow!(
148                "missing executable in directory {:?}",
149                last_version_dir
150            ))
151        }
152    })
153    .await
154    .log_err()
155}