local p = {}
local getArgs = require('Module:Arguments').getArgs
local timestamp = require('Module:Bengali Unix Timestamp').main
-- Return true if Bengali year is leap
local function isLeapYear(year)
return ((year - 594) % 4 == 0)
end
local function format_date(day, month, year, format)
local components = { d = day, m = month, y = year }
local result = {}
for i = 1, #format do
local char = format:sub(i, i)
if components[char] then
table.insert(result, components[char])
else
table.insert(result, char)
end
end
return table.concat(result)
end
local BN_MONTH = {
[1] = "Boisakh",
[2] = "Joishtho",
[3] = "Ashar",
[4] = "Shrabon",
[5] = "Bhadro",
[6] = "Ashshin",
[7] = "Kartik",
[8] = "Ogrohayon",
[9] = "Poush",
[10] = "Magh",
[11] = "Falgun",
[12] = "Chaitro"
}
function p.main(frame)
local args = getArgs(frame)
local input1 = args[1] or ''
local input2 = args[2] or ''
local format, dateInput
-- Check if input1 looks like a date (simple pattern check)
if input1:match("^%d+%-%d+%-%d+$") or input1:match("^%d+%s+%a+%s+%d+$") then
dateInput = input1
format = input2 ~= '' and input2 or 'm d y'
else
format = input1 ~= '' and input1 or 'm d y'
dateInput = input2 ~= '' and input2 or nil
end
local ts, err = getTimestamp(dateInput)
if not ts then
return string.format("Error: %s", err or "Invalid date.")
end
local second = 86400
local days = math.floor(ts / second)
local year = 1432
-- Bengali year calculation
if days >= 0 then
while true do
local leap = isLeapYear(year) and 366 or 365
if days < leap then break end
days = days - leap
year = year + 1
end
else
while true do
local leap = isLeapYear(year - 1) and 366 or 365
if -days <= leap then
year = year - 1
days = days + leap
break
end
days = days + leap
year = year - 1
end
end
local isLeap = isLeapYear(year)
local monthLengths = {31,31,31,31,31,31,30,30,30,30,30, isLeap and 30 or 29}
local month = 1
while days >= monthLengths[month] do
days = days - monthLengths[month]
month = month + 1
end
local day = days + 1
return format_date(day, BN_MONTH[month], year, format)
end
return p
