;;; lsp.el --- Language Server Protocol.             -*- lexical-binding: t; -*-

;; Time-stamp: <2020-07-07T05:33:56+0200>

;;; Commentary:

;;; Code:

(require 'basics/package-management)
(require 'basics/global-variables)
(require 'programming/common)

(unless slow-computer
  ;; Client for Language Server Protocol servers.
  (use-package lsp-mode
    :if (executable-find "clangd")
    :defines (lsp-clients-clangd-args)
    :diminish lsp-mode
    :custom ((lsp-prefer-flymake nil)     ; Disable flymake.
             (lsp-auto-guess-root t)      ; Don't ask for project root.
             (lsp-eldoc-render-all t)
             (lsp-restart 'auto-restart)
             (lsp-enable-semantic-highlighting t) ; Needs clangd 11(?).
             (lsp-prefer-capf t))
    :config (progn
              (setq lsp-clients-clangd-args '("--compile-commands-dir=build"))
              ;; Add “-clang-tidy” to clangd args if the version supports it.
              (when (>= (my/clangd-version) 9.0)
                (add-to-list 'lsp-clients-clangd-args "--clang-tidy" t))
              ;; Mark lsp-clients-clangd-args as safe to override.
              (put 'lsp-clients-clangd-args 'safe-local-variable #'consp))
    :bind ("C-c C-f" . lsp-execute-code-action)
    :hook ((c++-mode . lsp)
           (c-mode . lsp)
           ;; ↓ See <https://github.com/emacs-lsp/lsp-mode/issues/1736>. ↓
           (lsp-managed-mode
            . (lambda () (setq-local company-backends '(company-capf))))))

  ;; Eye-candy and flycheck support for lsp-mode.
  (use-package lsp-ui
    :after (lsp-mode flycheck whitespace)
    :functions (my/whitespace-mode-on my/whitespace-mode-off)
    :custom ((lsp-ui-sideline-enable nil)     ; Do not insert doc into buffer.
             (lsp-ui-doc-include-signature t) ; Include signature in doc popup.
             (lsp-ui-doc-enable nil))         ; Disable doc popup.
    :config (defun my/lsp-ws-toggle ()
              "Works around the dots-in-wrong-color bug."
              (if lsp-ui-peek-mode
                  (my/whitespace-mode-off)
                (my/whitespace-mode-on)))
    :bind (:map lsp-ui-mode-map
                ("M-." . lsp-ui-peek-find-definitions)
                ("C-M-." . lsp-ui-peek-find-references)
                ("C-M-," . lsp-ui-peek-find-implementation))
    :hook ((lsp-mode . lsp-ui-mode)
           (lsp-ui-peek-mode . my/lsp-ws-toggle)))

  ;; ivy interface to lsp-mode.
  (use-package lsp-ivy
    :demand t
    :after (lsp-mode ivy))

  ;; Integration between lsp-mode and treemacs.
  (use-package lsp-treemacs
    :after (treemacs lsp-ui)
    :bind (:map lsp-ui-mode-map
                ("<f7>" . lsp-treemacs-errors-list)
                ("M-i" . lsp-treemacs-symbols)))
  ) ; unless slow-computer.

(provide 'programming/lsp)
;;; lsp.el ends here