RosettaCodeData/Task/Calendar/Clojure/calendar.clj

127 lines
4.1 KiB
Clojure

(require '[clojure.string :only [join] :refer [join]])
(def day-row "Su Mo Tu We Th Fr Sa")
(def col-width (count day-row))
(defn month-to-word
"Translate a month from 0 to 11 into its word representation."
[month]
((vec (.getMonths (new java.text.DateFormatSymbols))) month))
(defn month [date]
(.get date (java.util.Calendar/MONTH)))
(defn total-days-in-month [date]
(.getActualMaximum date (java.util.Calendar/DAY_OF_MONTH)))
(defn first-weekday [date]
(.get date (java.util.Calendar/DAY_OF_WEEK)))
(defn normal-date-string
"Returns a formatted list of strings of the days of the month."
[date]
(map #(join " " %)
(partition 7
(concat
(repeat (dec (first-weekday date)) " ")
(map #(format "%2s" %)
(range 1 (inc (total-days-in-month date))))
(repeat (- 42 (total-days-in-month date)
(dec (first-weekday date)) ) " ")))))
(defn oct-1582-string
"Returns a formatted list of strings of the days of the month of October 1582."
[date]
(map #(join " " %)
(partition 7
(concat
(repeat (dec (first-weekday date)) " ")
(map #(format "%2s" %)
(concat (range 1 5)
(range 15 (inc (total-days-in-month date)))))
(repeat (- 42
(count (concat (range 1 5)
(range 15
(inc (total-days-in-month date)))))
(dec (first-weekday date)) ) " ")))))
(defn center-string
"Returns a string that is WIDTH long with STRING centered in it."
[string width]
(let [pad (- width (count string))
lpad (quot pad 2)
rpad (- pad (quot pad 2))]
(if (<= pad 0)
string
(str (apply str (repeat lpad " ")) ; remove vector
string
(apply str (repeat rpad " "))))))
(defn calc-columns
"Calculates the number of columns given the width in CHARACTERS and the
MARGIN SIZE."
[characters margin-size]
(loop [cols 0 excess characters ]
(if (>= excess col-width)
(recur (inc cols) (- excess (+ margin-size col-width)))
cols)))
(defn month-vector
"Returns a vector with the month name, day-row and days
formatted for printing."
[date]
(vec (concat
(vector (center-string (month-to-word (month date)) col-width))
(vector day-row)
(if (and (= 1582 (.get date (java.util.Calendar/YEAR)))
(= 9 (month date)))
(oct-1582-string date)
(normal-date-string date)))))
(defn year-vector [date]
"Returns a 2d vector of all the months in the year of DATE."
(loop [m [] c (month date)]
(if (= c 11 )
(conj m (month-vector date))
(recur (conj m (month-vector date))
(do (.add date (java.util.Calendar/MONTH ) 1)
(month date))))))
(defn print-months
"Prints the months to standard output with NCOLS and MARGIN."
[ v ncols margin]
(doseq [r (range (Math/ceil (/ 12 ncols)))]
(do (doseq [i (range 8)]
(do (doseq [c (range (* r ncols) (* (+ r 1) ncols))
:while (< c 12)]
(printf (str (apply str (repeat margin " ")) "%s")
(get-in v [c i])))
(println)))
(println))))
(defn print-cal
"(print-cal [year [width [margin]]])
Prints out the calendar for a given YEAR with WIDTH characters wide and
with MARGIN spaces between months."
([]
(print-cal 1969 80 2))
([year]
(print-cal year 80 2))
([year width]
(print-cal year width 2))
([year width margin]
(assert (>= width (count day-row)) "Width should be more than 20.")
(assert (> margin 0) "Margin needs to be more than 0.")
(let [date (new java.util.GregorianCalendar year 0 1)
column-count (calc-columns width margin)
total-size (+ (* column-count (count day-row))
(* (dec column-count) margin))]
(println (center-string "[Snoopy Picture]" total-size))
(println (center-string (str year) total-size))
(println)
(print-months (year-vector date) column-count margin))))