#+title: Setup Fschl Ide Configuration
#+PROPERTY: header-args:emacs-lisp :tangle ./modules/fschl-ide.el :mkdirp yes :tangle-mode "ugo=r"

* Basic configuration
** Additional Packages
#+begin_src emacs-lisp
  ;;; fschl-ide.el -- Fschl Crafted Emacs user customization file -*- lexical-binding: t; -*-
  ;; This file is generated from the .org-file with the same name. If you want to edit the
  ;; configuration, DO NOT edit this .el-file, edit .org, instead.

  (add-to-list 'package-selected-packages 'cargo)
  (add-to-list 'package-selected-packages 'rustic)
  (add-to-list 'package-selected-packages 'ob-rust)
  (add-to-list 'package-selected-packages 'ob-rust)
  (package-install-selected-packages :noconfirm)
#+end_src

** Setup Rustic                                                    :noexport:

This is borrowed from https://robert.kra.hn/posts/rust-emacs-setup/
#+begin_src emacs-lisp :tangle no
  (use-package rustic
    :ensure
    :bind (:map rustic-mode-map
                ("M-j" . lsp-ui-imenu)
                ("M-ö" . lsp-find-references)
                ("C-c C-c l" . flycheck-list-errors)
                ("C-c C-c a" . lsp-execute-code-action)
                ("C-c C-c r" . lsp-rename)
                ("C-c C-c q" . lsp-workspace-restart)
                ("C-c C-c Q" . lsp-workspace-shutdown)
                ("C-c C-c s" . lsp-rust-analyzer-status))
    :config
    ;; uncomment for less flashiness
    ;; (setq lsp-eldoc-hook nil)
    ;; (setq lsp-enable-symbol-highlighting nil)
    ;; (setq lsp-signature-auto-activate nil)

    ;; comment to disable rustfmt on save
    (setq rustic-format-on-save t)
    (add-hook 'rustic-mode-hook 'rk/rustic-mode-hook))

  (defun rk/rustic-mode-hook ()
    ;; so that run C-c C-c C-r works without having to confirm, but don't try to
    ;; save rust buffers that are not file visiting. Once
    ;; https://github.com/brotzeit/rustic/issues/253 has been resolved this should
    ;; no longer be necessary.
    (when buffer-file-name
      (setq-local buffer-save-without-query t))
    (add-hook 'before-save-hook 'lsp-format-buffer nil t))
#+end_src

** Setup LSP-mode and LSP-ui                                       :noexport:
#+begin_src emacs-lisp :tangle no
  (use-package lsp-mode
  :ensure
  :commands lsp
  :custom
  ;; what to use when checking on-save. "check" is default, I prefer clippy
  (lsp-rust-analyzer-cargo-watch-command "clippy")
  (lsp-eldoc-render-all t)
  (lsp-idle-delay 0.6)
  ;; enable / disable the hints as you prefer:
  (lsp-inlay-hint-enable t)
  ;; These are optional configurations. See https://emacs-lsp.github.io/lsp-mode/page/lsp-rust-analyzer/#lsp-rust-analyzer-display-chaining-hints for a full list
  (lsp-rust-analyzer-display-lifetime-elision-hints-enable "skip_trivial")
  (lsp-rust-analyzer-display-chaining-hints t)
  (lsp-rust-analyzer-display-lifetime-elision-hints-use-parameter-names nil)
  (lsp-rust-analyzer-display-closure-return-type-hints t)
  (lsp-rust-analyzer-display-parameter-hints nil)
  (lsp-rust-analyzer-display-reborrow-hints nil)
  :config
  (add-hook 'lsp-mode-hook 'lsp-ui-mode))

(use-package lsp-ui
  :ensure
  :commands lsp-ui-mode
  :custom
  (lsp-ui-peek-always-show t)
  (lsp-ui-sideline-show-hover t)
  (lsp-ui-doc-enable nil))
#+end_src

** Rust-Mode with Eglot

inspired by [[https://unwoundstack.com/blog/emacs-as-a-rust-ide.html][unwoundstack.com > Blog > Emacs as Rust IDE]] 

#+begin_src lisp :tangle ./modules/fschl-ide.el
(use-package smartparens :ensure t
  :config (require 'smartparens-rust))

(defun sp1ff/rust/mode-hook ()
  "My rust-mode hook"

  (column-number-mode)
  (display-line-numbers-mode)
  (hs-minor-mode)
  (smartparens-mode)
  (define-key rust-mode-map "\C-ca" 'eglot-code-actions)
  (define-key rust-mode-map (kbd "C-<right>")   'sp-forward-slurp-sexp)
  (define-key rust-mode-map (kbd "C-<left>")    'sp-forward-barf-sexp)
  (define-key rust-mode-map (kbd "C-M-<right>") 'sp-backward-slurp-sexp)
  (define-key rust-mode-map (kbd "C-M-<left>")  'sp-backward-barf-sexp)
  (define-key rust-mode-map "\C-c>" 'hs-show-all)
  (define-key rust-mode-map "\C-c<" 'hs-hide-all)
  (define-key rust-mode-map "\C-c-" 'hs-toggle-hiding)
  (define-key rust-mode-map "\C-c+" 'hs-hide-level)
  (setq indent-tabs-mode nil
        tab-width 4
        c-basic-offset 4
        fill-column 100))

(use-package rust-mode
  :ensure t
  :hook (rust-mode . sp1ff/rust/mode-hook)
  :config
  (let ((dot-cargo-bin (expand-file-name "~/.cargo/bin/")))
    (setq rust-rustfmt-bin (concat dot-cargo-bin "rustfmt")
          rust-cargo-bin (concat dot-cargo-bin "cargo")
          rust-format-on-save t)))

(use-package clippy-flymake
  :vc (:url "https://git.sr.ht/~mgmarlow/clippy-flymake" :branch main)
  :hook (rust-mode . clippy-flymake-setup-backend))

(defun clippy-flymake-manually-activate-flymake ()
  "Shim for working around eglot's tendency to suppress flymake backends."
  (add-hook 'flymake-diagnostic-functions #'eglot-flymake-backend nil t)
  (flymake-mode 1))

;; `eglot' by default will suppress all other flymake backends than its own
;; <https://github.com/joaotavora/eglot/issues/268> This workaround will
;; add `flymake-clippy'
(use-package eglot
  :ensure t
  :hook ((rust-mode . eglot-ensure)
         (eglot-managed-mode . clippy-flymake-manually-activate-flymake))
  :config
  (add-to-list 'eglot-stay-out-of 'flymake))
  #+end_src

** Auto-completion
lsp-mode integrates with company mode

#+begin_src emacs-lisp  :tangle ./modules/fschl-ide.el
  (use-package company
  :ensure
  :custom
  (company-idle-delay 0.5) ;; how long to wait until popup
  ;; (company-begin-commands nil) ;; uncomment to disable popup
  :bind
  (:map company-active-map
	      ("C-n". company-select-next)
	      ("C-p". company-select-previous)
	      ("M-<". company-select-first)
	      ("M->". company-select-last)))
#+end_src

** Inline stuff

hints and errors
#+begin_src emacs-lisp
  (use-package flycheck :ensure)
  (setq lsp-inlay-hint-enable t)
#+end_src