use std::fs;use zed::lsp::CompletionKind;use zed::{CodeLabel, CodeLabelSpan, LanguageServerId};use zed_extension_api::{self as zed, Result}; struct LuaExtension {    cached_binary_path: Option<String>,} impl LuaExtension {    fn language_server_binary_path(        &mut self,        language_server_id: &LanguageServerId,        worktree: &zed::Worktree,    ) -> Result<String> {        if let Some(path) = worktree.which("lua-language-server") {            return Ok(path);        }         if let Some(path) = &self.cached_binary_path {            if fs::metadata(path).map_or(false, |stat| stat.is_file()) {                return Ok(path.clone());            }        }         zed::set_language_server_installation_status(            &language_server_id,            &zed::LanguageServerInstallationStatus::CheckingForUpdate,        );        let release = zed::latest_github_release(            "LuaLS/lua-language-server",            zed::GithubReleaseOptions {                require_assets: true,                pre_release: false,            },        )?;         let (platform, arch) = zed::current_platform();        let asset_name = format!(            "lua-language-server-{version}-{os}-{arch}.tar.gz",            version = release.version,            os = match platform {                zed::Os::Mac => "darwin",                zed::Os::Linux => "linux",                zed::Os::Windows => "win32",            },            arch = match arch {                zed::Architecture::Aarch64 => "arm64",                zed::Architecture::X8664 => "x64",                zed::Architecture::X86 => return Err("unsupported platform x86".into()),            },        );         let asset = release            .assets            .iter()            .find(|asset| asset.name == asset_name)            .ok_or_else(|| format!("no asset found matching {:?}", asset_name))?;         let version_dir = format!("lua-language-server-{}", release.version);        let binary_path = format!("{version_dir}/bin/lua-language-server");         if !fs::metadata(&binary_path).map_or(false, |stat| stat.is_file()) {            zed::set_language_server_installation_status(                &language_server_id,                &zed::LanguageServerInstallationStatus::Downloading,            );             zed::download_file(                &asset.download_url,                &version_dir,                zed::DownloadedFileType::GzipTar,            )            .map_err(|e| format!("failed to download file: {e}"))?;             let entries =                fs::read_dir(".").map_err(|e| format!("failed to list working directory {e}"))?;            for entry in entries {                let entry = entry.map_err(|e| format!("failed to load directory entry {e}"))?;                if entry.file_name().to_str() != Some(&version_dir) {                    fs::remove_dir_all(&entry.path()).ok();                }            }        }         self.cached_binary_path = Some(binary_path.clone());        Ok(binary_path)    }} impl zed::Extension for LuaExtension {    fn new() -> Self {        Self {            cached_binary_path: None,        }    }     fn language_server_command(        &mut self,        language_server_id: &LanguageServerId,        worktree: &zed::Worktree,    ) -> Result<zed::Command> {        Ok(zed::Command {            command: self.language_server_binary_path(language_server_id, worktree)?,            args: Default::default(),            env: Default::default(),        })    }     fn label_for_completion(        &self,        _language_server_id: &LanguageServerId,        completion: zed::lsp::Completion,    ) -> Option<CodeLabel> {        match completion.kind? {            CompletionKind::Method | CompletionKind::Function => {                let name_len = completion.label.find('(').unwrap_or(completion.label.len());                Some(CodeLabel {                    spans: vec![CodeLabelSpan::code_range(0..completion.label.len())],                    filter_range: (0..name_len).into(),                    code: completion.label,                })            }            CompletionKind::Field => Some(CodeLabel {                spans: vec![CodeLabelSpan::literal(                    completion.label.clone(),                    Some("property".into()),                )],                filter_range: (0..completion.label.len()).into(),                code: Default::default(),            }),            _ => None,        }    }     fn label_for_symbol(        &self,        _language_server_id: &LanguageServerId,        symbol: zed::lsp::Symbol,    ) -> Option<CodeLabel> {        let prefix = "let a = ";        let suffix = match symbol.kind {            zed::lsp::SymbolKind::Method => "()",            _ => "",        };        let code = format!("{prefix}{}{suffix}", symbol.name);        Some(CodeLabel {            spans: vec![CodeLabelSpan::code_range(                prefix.len()..code.len() - suffix.len(),            )],            filter_range: (0..symbol.name.len()).into(),            code,        })    }} zed::register_extension!(LuaExtension);