X-Git-Url: https://git.madduck.net/etc/awesome.git/blobdiff_plain/b7645320a1905587b16a8b2035481bbd45788175..d08da842dbdcc2b452fdb6a70cb82f6cc85dc118:/luatz/tzinfo.lua

diff --git a/luatz/tzinfo.lua b/luatz/tzinfo.lua
index 5b7c0c0..e37483f 100644
--- a/luatz/tzinfo.lua
+++ b/luatz/tzinfo.lua
@@ -1,40 +1,51 @@
 local gettime = require "luatz.gettime".gettime
+local timetable_mt = require "luatz.timetable".timetable_mt
+
+local function to_timestamp(o)
+	if type(o) == "number" then
+		return o
+	elseif getmetatable(o) == timetable_mt then
+		return o:timestamp()
+	end
+end
 
 local tz_info_methods = { }
 local tz_info_mt = {
-	__index = tz_info_methods ;
+	__name = "luatz.tz_info";
+	__index = tz_info_methods;
 }
 local tt_info_mt = {
-	__tostring = function ( self )
-		return string.format ( "tt_info:%s=%d" , self.abbr , self.gmtoff )
-	end ;
+	__name = "luatz.tt_info";
+	__tostring = function(self)
+		return string.format("tt_info:%s=%d", self.abbr, self.gmtoff)
+	end;
 }
 
 -- Binary search
-local function _find_current ( tzinfo , target , i , j )
+local function find_current(tzinfo, target, i, j)
 	if i >= j then return j end
 
-	local half = math.ceil ( (j+i) / 2 )
+	local half = math.ceil((j+i) / 2)
 
-	if target >= tzinfo [ half ].transition_time then
-		return _find_current ( tzinfo , target , half , j )
+	if target >= tzinfo[half].transition_time then
+		return find_current(tzinfo, target, half, j)
 	else
-		return _find_current ( tzinfo , target , i , half-1 )
+		return find_current(tzinfo, target, i, half-1)
 	end
 end
 
-local function find_current_local ( tzinfo , ts_local )
+local function find_current_local(tzinfo, ts_local)
 	-- Find two best possibilities by searching back and forward a day (assumes transition is never by more than 24 hours)
-	local tz_first = _find_current ( tzinfo , ts_local-86400 , 0 , #tzinfo )
-	local tz_last  = _find_current ( tzinfo , ts_local+86400 , 0 , #tzinfo )
+	local tz_first = find_current(tzinfo, ts_local-86400, 0, #tzinfo)
+	local tz_last  = find_current(tzinfo, ts_local+86400, 0, #tzinfo)
 
 	local n_candidates = tz_last - tz_first + 1
 
 	if n_candidates == 1 then
 		return tz_first
 	elseif n_candidates == 2 then
-		local tz_first_ob = tzinfo [ tz_first ]
-		local tz_last_ob  = tzinfo [ tz_last ]
+		local tz_first_ob = tzinfo[tz_first]
+		local tz_last_ob  = tzinfo[tz_last]
 
 		local first_gmtoffset = tz_first_ob.info.gmtoff
 		local last_gmtoffset  = tz_last_ob .info.gmtoff
@@ -50,35 +61,37 @@ local function find_current_local ( tzinfo , ts_local )
 		end
 
 		-- If we get this far, the local time is ambiguous
-		return tz_first , tz_last
+		return tz_first, tz_last
 	else
-		error ( "Too many transitions in a 2 day period" )
+		error("Too many transitions in a 2 day period")
 	end
 end
 
-function tz_info_methods:find_current ( current )
-	return self [ _find_current ( self , current , 0 , #self ) ].info
+function tz_info_methods:find_current(current)
+	current = assert(to_timestamp(current), "invalid timestamp to :find_current")
+	return self[find_current(self, current, 0, #self)].info
 end
 
-function tz_info_methods:localise ( utc_ts )
-	utc_ts = utc_ts or gettime ( )
-	return utc_ts + self:find_current ( utc_ts ).gmtoff
+function tz_info_methods:localise(utc_ts)
+	utc_ts = utc_ts or gettime()
+	return utc_ts + self:find_current(utc_ts).gmtoff
 end
 tz_info_methods.localize = tz_info_methods.localise
 
-function tz_info_methods:utctime ( ts_local )
-	local tz1 , tz2 = find_current_local ( self , ts_local )
-	tz1 = self [ tz1 ].info
+function tz_info_methods:utctime(ts_local)
+	ts_local = assert(to_timestamp(ts_local), "invalid timestamp to :utctime")
+	local tz1, tz2 = find_current_local(self, ts_local)
+	tz1 = self[tz1].info
 	if tz2 == nil then
 		return ts_local - tz1.gmtoff
 	else -- Local time is ambiguous
-		tz2 = self [ tz2 ].info
+		tz2 = self[tz2].info
 
-		return ts_local - tz2.gmtoff , ts_local - tz2.gmtoff
+		return ts_local - tz2.gmtoff, ts_local - tz2.gmtoff
 	end
 end
 
 return {
-	tz_info_mt = tz_info_mt ;
-	tt_info_mt = tt_info_mt ;
+	tz_info_mt = tz_info_mt;
+	tt_info_mt = tt_info_mt;
 }