;;; macros.fnl - useful macros

;; Helpful keymaping functions
(lambda bind! [mode key cmd ?a1 ?a2]
  (let [desc (or ?a2 ?a1)
        buf (if (and ?a1 ?a2) ?a1 ?a2)
        opts { :noremap true
               :silent true
               :buffer buf }]
    (when desc
      (tset opts :desc desc))
    `(vim.keymap.set ,mode ,key ,cmd ,opts)))

;; Better autocommands
(lambda hook! [hooks ?patterns callback]
  (let [hook_table (if (= (type hooks) :table)
                       hooks
                       [ hooks ])
        pattern_table (if (not ?patterns)
                           []
                           (= (type ?patterns) :table)
                           ?patterns
                           [ ?patterns ])]
    (var group "config-hook")
    (each [_ hook (ipairs hook_table)]
      (set group (.. group "-" hook)))
    (each [_ pattern (ipairs pattern_table)]
      (set group (.. group "-" pattern)))
    `(vim.api.nvim_create_autocmd ,hook_table
                                  { :group
                                    (vim.api.nvim_create_augroup ,group
                                                                 { :clear true })
                                    :pattern ,pattern_table
                                    :callback ,callback })))
;; Nicer macro for use
;; (lambda use! [repo ...]
;;   (local output [ repo ])
;;   (var last_key nil)
;;   (each [_ val (ipairs [...])]
;;     (if last_key
;;         (do (tset output last_key val)
;;             (set last_key nil))
;;         (set last_key val)))
;;   `(use ,output))
(lambda use! [repo ...]
  (local output [ repo ])
  (var last_key nil)
  (var config_mode false)
  (var has_config false)
  (var config_entries (list `lambda []))
  (each [_ val (ipairs [...])]
    (if config_mode
        (if (= (type val) :string)
            (set config_mode false)
            (table.insert config_entries val))
        last_key
        (do (tset output last_key val)
            (set last_key nil))
        (= val :config)
        (do (set config_mode true)
            (set has_config true))
        (set last_key val)))
  (if has_config
      (tset output :config config_entries))
  `(use ,output))

;; Can be passed to :config of `use!'
;; to call a plugin's `setup' function
(lambda setup! [pkg ...] (local output [ ])
  (var last_key nil)
  (each [_ val (ipairs [...])]
    (if last_key
        (do (tset output last_key val)
          (set last_key nil))
        (set last_key val)))
  `((. (require ,pkg) :setup) ,output))

;; Call module function
(lambda module-call! [mod func ...]
  `((. (require ,mod) ,func) ,...))

;; Return  module function
(lambda module-fn! [mod func]
  `(. (require ,mod) ,func))

{: bind!
 : hook!
 : use!
 : setup!
 : module-call!
 : module-fn!}