edit.clj

(ns clojure-lsp.refactor.edit
  (:require
   [clojure.set :as set]
   [rewrite-clj.node :as n]
   [rewrite-clj.zip :as z]))

(set! *warn-on-reflection* true)

(defn root? [loc]
  (identical? :forms (z/tag loc)))

(defn top? [loc]
  (root? (z/up loc)))

(defn to-top
  "Returns the loc for the top-level form above the loc, or the loc itself if it
  is top-level, or nil if the loc is at the `:forms` node."
  [loc]
  (z/find loc z/up top?))

;; From rewrite-cljs; very similar to the private function
;; rewrite-clj.zip.findz/position-in-range? but based on zloc meta, avoiding the
;; need for :track-position?
(defn in-range?
  "True if b is contained within a."
  [{:keys [row col end-row end-col] :as _a}
   {r :row c :col er :end-row ec :end-col :as _b}]
  (and (>= r row)
       (<= er end-row)
       (if (= r row) (>= c col) true)
       (if (= er end-row) (< ec end-col) true)))

(defn ^:private zloc-in-range?
  "Checks whether the `loc`s node is [[in-range?]] of the given `pos`."
  [loc pos]
  (some-> loc z/node meta (in-range? pos)))

(defn find-by-heritability
  "Find the leftmost deepest zloc from `start-zloc` that satisfies `inherits?`.
  `inherits?` must be a function such that if zloc satisifies it then so will
  all of its ancestors.

  If a parent node satisifies `inherits?` but none of its children do, then this
  returns the parent, on the assumption that the parent is the last in its
  lineage with the trait.

  If a parent node doesn't satisfy `inherits?` then none of its descendants will
  be inspected. Instead, the search will continue with its sibling to the
  z/right*. As such, this algoritihm can be much faster than ones based on
  z/next*, which must inspect all descendants, even if information in the parent
  excludes the entire family."
  [start-zloc inherits?]
  (loop [zloc (cond-> start-zloc
                (= :forms (z/tag start-zloc)) z/down*)]
    (if (z/end? zloc)
      zloc
      (if (inherits? zloc)
        (if-let [inner (some-> zloc z/down* (z/find z/right* inherits?))]
          (recur inner)
          zloc)
        (recur (z/right* zloc))))))

(defn find-at-pos
  "Find the deepest zloc whose node is at the given `row` and `col`, seeking
  from initial zipper location `zloc`.

  This is similar to z/find-last-by-pos, but is faster, and doesn't require
  {:track-position? true}."
  [zloc row col]
  (let [exact-position {:row row, :col col, :end-row row, :end-col col}]
    (find-by-heritability zloc #(zloc-in-range? % exact-position))))

(defn find-op
  [zloc]
  (loop [op-loc (or (and (= :list (z/tag zloc))
                         (z/down zloc))
                    (z/leftmost zloc))]
    (let [up-loc (z/up op-loc)]
      (cond
        (nil? up-loc) nil
        (= :list (z/tag up-loc)) op-loc
        :else (recur (z/leftmost up-loc))))))

(defn find-ops-up
  [zloc & op-strs]
  (loop [op-loc (find-op zloc)]
    (cond
      (nil? op-loc)
      nil

      (and (= :token (z/tag op-loc))
           (contains? (set op-strs)
                      (let [sexpr (-> op-loc z/string symbol)]
                        (if (qualified-ident? sexpr)
                          (name sexpr)
                          (str sexpr)))))
      op-loc

      :else
      (recur (z/leftmost (z/up op-loc))))))

(defn var-name-loc-from-op [loc]
  (cond
    (not loc)
    nil

    (= :map (-> loc z/next z/tag))
    (-> loc z/next z/right)

    (and (= :meta (-> loc z/next z/tag))
         (= :map (-> loc z/next z/next z/tag)))
    (-> loc z/next z/down z/rightmost)

    (= :meta (-> loc z/next z/tag))
    (-> loc z/next z/next z/next)

    :else
    (z/next loc)))

(defn find-var-definition-name-loc [loc]
  (some-> loc to-top z/next var-name-loc-from-op))

(defn find-function-usage-name-loc [zloc]
  (some-> zloc (z/find z/up #(contains? #{:list :fn} (z/tag %))) z/down))

(defn single-child?
  [zloc]
  (let [child (z/down zloc)]
    (and child
         (z/leftmost? child)
         (z/rightmost? child))))

;; from rewrite-cljs
(defn raise
  "Delete siblings and raise node at zloc one level up
  - `[1 [2 |3 4]] => [1 |3]`"
  [zloc]
  (if-let [containing (z/up zloc)]
    (-> containing
        (z/replace (z/node zloc)))
    zloc))

(defn map-children [parent-zloc f]
  (if (z/down parent-zloc)
    (z/subedit->> parent-zloc
                  z/down
                  (iterate (fn [zloc]
                             (when (not (z/end? zloc))
                               (-> zloc f z/next))))
                  (take-while identity)
                  last)
    parent-zloc))

(defn wrap-around [zloc tag]
  (let [node (z/node zloc)
        node-meta (meta node)]
    (-> zloc
        (z/replace (-> (case tag
                         :list (n/list-node [])
                         :vector (n/vector-node [])
                         :set (n/set-node [])
                         :map (n/map-node []))
                       (with-meta node-meta)))
        (z/insert-child node))))

(defn parent-let? [zloc]
  (let [parent-op (-> zloc z/leftmost)]
    (when (= 'let (-> parent-op z/sexpr))
      (z/up parent-op))))

(defn join-let
  "if a let is directly above a form, will join binding forms and remove the inner let"
  [let-loc]
  (if (parent-let? let-loc)
    (let [bind-node (z/node (z/right (z/down let-loc)))]
      (-> let-loc
          (z/down)
          (z/right) ; move to inner binding
          (z/remove) ; remove inner binding
          (z/remove) ; remove inner let moving to prev; the surrounding list
          (z/splice) ; splice let body into outer let body
          (z/leftmost) ; move to let
          (z/right) ; move to parent binding
          (z/append-child bind-node) ; place into binding
          (z/down) ; move into binding
          (z/rightmost) ; move to nested binding
          (z/splice) ; remove nesting
          z/left
          (z/insert-right* (n/newlines 1))
          (z/up) ; move to new binding
          (z/up))) ; move to let-form
    let-loc))

(defn inside-require? [zloc]
  (or (and (find-ops-up zloc "ns")
           (find-ops-up zloc ":require"))
      (find-ops-up zloc "require")))

(defn inside-refer? [zloc]
  (and (inside-require? zloc)
       (or (and (= :vector (z/tag zloc))
                (= :refer (-> zloc z/left z/sexpr)))
           (and (= :token (z/tag zloc))
                (= :refer (-> zloc z/up z/left z/sexpr))))))

(defn find-refer-ns [zloc]
  (when (inside-refer? zloc)
    (if (= :vector (z/tag zloc))
      (z/leftmost zloc)
      (z/leftmost (z/up zloc))))) ; ns form

(defn to-root
  "Returns the loc of the root `:forms` node."
  [loc]
  (z/find loc z/up root?))

(defn find-namespace [zloc]
  (-> (to-root zloc)
      (z/find-value z/next 'ns) ; go to ns
      (z/up))) ; ns form

(defn node-marked? [node marker]
  (contains? (get node ::markers) marker))

(defn marked? [loc marker]
  (node-marked? (z/node loc) marker))

(defn back-to-mark-or-nil
  [zloc marker]
  (z/find zloc z/prev (fn [loc] (marked? loc marker))))

(defn mark-position
  [zloc marker]
  (z/replace zloc (update (z/node zloc) ::markers (fnil conj #{}) marker)))

(defn mark-position-when
  [zloc marker p?]
  (if p?
    (mark-position zloc marker)
    zloc))

(defn range-with-left-whitespace [zloc]
  (let [this (some-> zloc z/node meta)
        next-left (some-> zloc z/left z/node meta)]
    {:row (or (:end-row next-left) (:row this))
     :col (or (:end-col next-left) (:col this))
     :end-row (:end-row this)
     :end-col (:end-col this)}))

(defn range-from-usage-name [usage]
  (set/rename-keys
    usage
    {:name-row :row :name-col :col
     :name-end-row :end-row :name-end-col :end-col}))

(defn to-top-or-subzip-top
  "to-top will return nil within a subzip, sometimes that is unwanted"
  [loc]
  (if-let [up-loc (when-not (top? loc) (z/up loc))]
    (recur up-loc)
    loc))

(defn find-at-usage-name [zloc usage]
  (some-> zloc
          to-top-or-subzip-top
          z/leftmost
          (find-at-pos (:name-row usage)
                       (:name-col usage))))

(defn find-at-usage [zloc usage]
  (some-> zloc
          to-top-or-subzip-top
          z/leftmost
          (find-at-pos (:row usage)
                       (:col usage))))

(defn loc-encapsulates-usage?
  [loc usage]
  (in-range? (meta (z/node loc)) (range-from-usage-name usage)))