(ns auto-ap.parse
  (:require [clojure.java.io :as io]
            [clojure.string :as str]
            [clojure.java.shell :as sh]))

(def templates
  [{:keywords [#"CHEF'S WAREHOUSE"]
    :extract {:total #"2 WKS C\.C\.\s+([\d.,]+)"
              :customer-identifier #"\n([A-Z][A-Z ]+)\s{2,}"
              :date #"\s+([0-9]+/[0-9]+/[0-9]+)"
              :invoice-number #"\s+[0-9]+/[0-9]+/[0-9]+\s+([0-9]+)"}}

   {:keywords [#"Golden Gate Meat"]
    :extract {:total #"Invoice Total\:\s+\$([\d.,]+)"
              :customer-identifier #"Bill To\s*:\s*([\w ]+)\s{2,}"
              :date #"Printed:\s+([0-9]+/[0-9]+/[0-9]+)"
              :invoice-number #"Invoice\s+[^\n]+\n[^\n]+\n\s+([0-9]+)"}}

   {:keywords [#"CINTAS CORPORATION"]
     :extract {:invoice-number #"INVOICE\s#\s+([\d.,]+)"
               :customer-identifier #"BILL TO\s*:\s{2,}([\w ]+)\s{2,}"
               :date #"INVOICE DATE\s*\n.*\s+([0-9]+/[0-9]+/[0-9]+)"
               :total #"INVOICE TOTAL\s+([0-9.]+)"}
    :multi #"\f\f"}])

(defn template-applies? [text {:keys [keywords]}]
  (every? #(re-find % text) keywords))

(defn extract-template [text template]
  (if (:multi template)
    (mapcat
     #(extract-template % (dissoc template :multi))
     (str/split text (:multi template)))

    [(->> template
           :extract
           (reduce-kv
            (fn [result k v]
              (assoc result k (some-> (first (map second (re-seq v text)))
                                      str/trim )))
            {}))]))

(defn parse [text]
  (->> templates
       (filter (partial template-applies? text))
       first
       (extract-template text)))

(defn parse-file
  [file]
  (->  (sh/sh "pdftotext" "-layout" file "-")
       :out
       parse))