(ns c.test
  (:use [clojure.core.match :only (match)])
  (:require [clojure.string :as str]
            [crux.api :as crux]
            [clojure.set :as set])
  (:import (crux.api ICruxAPI)))

(def ^ICruxAPI node
  (crux/start-node {:crux.node/topology :crux.standalone/topology
                    :crux.node/kv-store "crux.kv.memdb/kv"
                    :crux.kv/db-dir "data/db-dir-1"
                    :crux.standalone/event-log-dir "data/eventlog-1"
                    :crux.standalone/event-log-kv-store "crux.kv.memdb/kv"}))

(defn read-rules [file]
  (with-open [rdr (clojure.java.io/reader file)]
     (reduce conj [] (map #(vec (.split % " ")) (line-seq rdr)))))

(defn parse-deps [d]

  (let [escape-coma (map #(re-find #"[^,]+" %) d)
        split-or (map #(if (str/includes? % "|")
                         (vec (str/split % #"[|]"))
                         %) escape-coma)]
    (vector (vec split-or))))

(defn match-rule [v]
  (match v
         [target "<="] {:crux.db/id (keyword target) :target target :deps nil}
         [target "<=" & deps] {:crux.db/id (keyword target) :target target :deps (parse-deps deps)}))

(defn parse-rules [rules]
  (map match-rule rules))

(parse-rules (read-rules "resources/rules.txt"))
=>
({:crux.db/id :source0, :target "source0", :deps nil}
 {:crux.db/id :source1, :target "source1", :deps [["source0"]]}
 {:crux.db/id :source01, :target "source01", :deps [["source0" "source1"]]}
 {:crux.db/id :source2, :target "source2", :deps [["source0" "source5"]]}
 {:crux.db/id :source02, :target "source02", :deps [["source1"]]}
 {:crux.db/id :source3, :target "source3", :deps [["source1" "source2"]]}
 {:crux.db/id :source03, :target "source03", :deps [["source01"]]}
 {:crux.db/id :source001, :target "source001", :deps [["source3" "source01" ["source02" "source2"]]]})

(defn submit-crux [targets]
  (doseq [t targets]
    (crux/submit-tx
      node
      [[:crux.tx/put t]])))

(submit-crux (parse-rules (read-rules "resources/rules.txt")))

(defn find-all-targets []
  (crux/q (crux/db node)
          '{:find [t d]
            :where [[id :target t]
                    [id :deps d]]}))
(find-all-targets)
=>
#{["source02" ["source1"]]
  ["source3" ["source1" "source2"]]
  ["source03" ["source01"]]
  ["source1" ["source0"]]
  ["source2" ["source0" "source5"]]
  ["source0" nil]
  ["source01" ["source0" "source1"]]
  ["source001" ["source3" "source01" ["source02" "source2"]]]}


(defn only-computable [targets]
  (let [t (set (map first targets))
        d (set (flatten (map second targets)))
        not-computable (set (remove nil? (set/difference d t)))]
    (filter #(empty? (-> %
                         second
                         flatten
                         set
                         (set/intersection not-computable))) targets)))

(only-computable (find-all-targets))
=>
(["source02" ["source1"]]
 ["source3" ["source1" "source2"]]
 ["source03" ["source01"]]
 ["source1" ["source0"]]
 ["source0" nil]
 ["source01" ["source0" "source1"]]
 ["source001" ["source3" "source01" ["source02" "source2"]]])