(ns tbd.todo.db-test
  (:require [clojure.java.io :as io]
            [clojure.test :refer [deftest is testing]]
            [tbd.todo.db :as db])
  (:import (java.nio.file Files)
           (java.nio.file.attribute FileAttribute)))

(defn temp-db-path
  "A path for a database file inside a fresh temp directory (which `open` has to create a
  subdirectory of, as with the default data/todo.db)."
  []
  (str (Files/createTempDirectory "tbd-todo" (make-array FileAttribute 0)) "/data/todo.db"))

(defn todo [owner-id title]
  {:owner-id owner-id :title title :done false :created-at 1000 :updated-at 1000})

(deftest env-config-test
  (is (= {:db-path "data/todo.db"} (db/env-config {})))
  (is (= {:db-path "data/todo.db"} (db/env-config {"TODO_DB_PATH" "  "})))
  (is (= {:db-path "/var/todo.db"} (db/env-config {"TODO_DB_PATH" " /var/todo.db "}))))

(deftest open-test
  (testing "creates the file and its directory"
    (let [path (temp-db-path)]
      (db/open path)
      (is (.exists (io/file path)))))
  (testing "reopening keeps the data"
    (let [path (temp-db-path)
          saved (db/insert! (db/open path) (todo 7 "buy milk"))]
      (is (= [saved] (db/list-todos (db/open path) 7)))))
  (testing "a path is required"
    (doseq [path [nil "" " "]]
      (is (thrown? clojure.lang.ExceptionInfo (db/open path))))))

(deftest crud-test
  (let [ds (db/open (temp-db-path))
        saved (db/insert! ds (todo 7 "buy milk"))
        id (:id saved)]
    (testing "insert returns the stored todo with an id"
      (is (= (assoc (todo 7 "buy milk") :id id) saved))
      (is (not= id (:id (db/insert! ds (todo 7 "walk dog"))))))
    (testing "find and list"
      (is (= saved (db/find-todo ds 7 id)))
      (is (= ["buy milk" "walk dog"] (map :title (db/list-todos ds 7)))))
    (testing "update"
      (is (= (assoc saved :title "buy oat milk" :done true :updated-at 2000)
             (db/update! ds 7 (assoc saved :title "buy oat milk" :done true :updated-at 2000))))
      (is (= true (:done (db/find-todo ds 7 id)))))
    (testing "missing ids"
      (is (nil? (db/find-todo ds 7 999)))
      (is (nil? (db/update! ds 7 (assoc saved :id 999))))
      (is (false? (db/delete! ds 7 999))))
    (testing "delete"
      (is (true? (db/delete! ds 7 id)))
      (is (nil? (db/find-todo ds 7 id)))
      (is (false? (db/delete! ds 7 id))))))

(deftest owner-scoping-test
  (let [ds (db/open (temp-db-path))
        mine (db/insert! ds (todo 7 "mine"))
        theirs (db/insert! ds (todo 8 "theirs"))]
    (is (= [mine] (db/list-todos ds 7)))
    (is (= [theirs] (db/list-todos ds 8)))
    (is (= [] (db/list-todos ds 9)))
    (testing "another owner's todo can't be found, changed, or deleted by its id"
      (is (nil? (db/find-todo ds 8 (:id mine))))
      (is (nil? (db/update! ds 8 (assoc mine :title "hijacked"))))
      (is (false? (db/delete! ds 8 (:id mine))))
      (is (= mine (db/find-todo ds 7 (:id mine)))))))