JS for date validation

1 files changed, 35 insertions, 0 deletions

diff --git a/app/assets/javascripts/calendars.coffee b/app/assets/javascripts/calendars.coffee
new file mode 100644
index 000000000..ac5330cc8
--- /dev/null
+++ b/app/assets/javascripts/calendars.coffee
@@ -0,0 +1,35 @@
+
+isEmpty = (x) -> x == ''
+
+daySelector   = '#q_contains_date_3i'
+monthSelector = '#q_contains_date_2i'
+yearSelector  = '#q_contains_date_1i'
+
+dateSelectors = [ daySelector, monthSelector, yearSelector ]
+
+checkDate = (args...) ->
+  vals = args.map((ele) -> ele.val())
+  return if vals.find( isEmpty ) == "" # no checking needed, no checking possible yet
+
+  dates = vals.map (x) -> parseInt(x)
+  return if isLegalDate(dates)
+  $('.alert').text('illegal date')
+  $('.alert').show()
+
+legalDaysPerMonth = [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]
+
+isLeapYear = (year) ->
+  (year % 4 == 0) && ((year % 100 != 0) || (year % 1000 == 0))
+
+isLegalDate = (dates) ->
+  [day, month, year] = dates
+  return true if legalDaysPerMonth[month-1] >= day
+  return true if day == 29 && isLeapYear(year)
+  false
+
+defineChangeHandler = (selector) ->
+  $(selector).on 'change', ->
+    checkDate $(daySelector), $(monthSelector), $(yearSelector)
+
+$ ->
+  defineChangeHandler selector for selector in dateSelectors