Changes requestd via PR

1) mod changed to MOD
2) autogroup changed to autogrouper
3) prints "please select at least 2 images" if user attempts to run with fewer than 2 images selected
4) change visible module name to "auto group" (lower case)
5) changed soft max on slider to 60s
         - I also increase the hard max up to a full day, I saw no reason not to

Author: BzKevin

contrib/AutoGrouper.lua

@@ -37,7 +37,7 @@ selected images, the other button performs grouping on the entire active collect
 ]]
 
 local dt = require "darktable"
-local mod = 'autogroup'
+local MOD = 'autogrouper'
 local gettext = dt.gettext
 -- Tell gettext where to find the .mo file translating messages for a particular domain
 gettext.bindtextdomain("AutoGrouper",dt.configuration.config_dir.."/lua/locale/")
@@ -46,110 +46,113 @@ local function _(msgid)
 end
 
 local function InRange(test, low, high) --tests if test value is within range of low and high (inclusive)
-	if test >= low and test <= high then
-		return true
-	else
-		return false
-	end
+    if test >= low and test <= high then
+        return true
+    else
+        return false
+    end
 end
 
 local function CompTime(first, second) --compares the timestamps and returns true if first was taken before second
-	first_time = first.exif_datetime_taken
-	if string.match(first_time, '[0-9]') == nil then first_time = '9999:99:99 99:99:99' end
-	first_time = tonumber(string.gsub(first_time, '[^0-9]*',''))
-	second_time = second.exif_datetime_taken
-	if string.match(second_time, '[0-9]') == nil then second_time = '9999:99:99 99:99:99' end
-	second_time = tonumber(string.gsub(second_time, '[^0-9]*',''))
-	return first_time < second_time
+    first_time = first.exif_datetime_taken
+    if string.match(first_time, '[0-9]') == nil then first_time = '9999:99:99 99:99:99' end
+    first_time = tonumber(string.gsub(first_time, '[^0-9]*',''))
+    second_time = second.exif_datetime_taken
+    if string.match(second_time, '[0-9]') == nil then second_time = '9999:99:99 99:99:99' end
+    second_time = tonumber(string.gsub(second_time, '[^0-9]*',''))
+    return first_time < second_time
 end
 
 local function SeperateTime(str) --seperates the timestamp into individual components for used with OS.time operations
-	local cleaned = string.gsub(str, '[^%d]',':')
-	cleaned = string.gsub(cleaned, '::*',':')  --YYYY:MM:DD:hh:mm:ss
-	local year = string.sub(cleaned,1,4)
-	local month = string.sub(cleaned,6,7)
-	local day = string.sub(cleaned,9,10)
-	local hour = string.sub(cleaned,12,13)
-	local min = string.sub(cleaned,15,16)
-	local sec = string.sub(cleaned,18,19)
-	return {year = year, month = month, day = day, hour = hour, min = min, sec = sec}
+    local cleaned = string.gsub(str, '[^%d]',':')
+    cleaned = string.gsub(cleaned, '::*',':')  --YYYY:MM:DD:hh:mm:ss
+    local year = string.sub(cleaned,1,4)
+    local month = string.sub(cleaned,6,7)
+    local day = string.sub(cleaned,9,10)
+    local hour = string.sub(cleaned,12,13)
+    local min = string.sub(cleaned,15,16)
+    local sec = string.sub(cleaned,18,19)
+    return {year = year, month = month, day = day, hour = hour, min = min, sec = sec}
 end
 
 local function GetTimeDiff(curr_image, prev_image) --returns the time difference (in sec.) from current image and the previous image
-	local curr_time = SeperateTime(curr_image.exif_datetime_taken)
-	local prev_time = SeperateTime(prev_image.exif_datetime_taken)
-	return os.time(curr_time)-os.time(prev_time)
+    local curr_time = SeperateTime(curr_image.exif_datetime_taken)
+    local prev_time = SeperateTime(prev_image.exif_datetime_taken)
+    return os.time(curr_time)-os.time(prev_time)
 end
 
 local function main(on_collection)
-	local images = {}
-	if on_collection then 
-		local col_images = dt.collection
-		for i,image in ipairs(col_images) do --copy images to a standard table, table.sort barfs on type dt_lua_singleton_image_collection
-			table.insert(images,i,image)
-		end
-	else
-		images = dt.gui.selection()
-	end
-	dt.preferences.write(mod, 'active_gap', 'integer', GUI.gap.value)
-	if #images < 2 then return end
-	table.sort(images, function(first, second) return CompTime(first,second) end)  --sort images by timestamp
-	
-	for i, image in ipairs(images) do
-		if i == 1 then 
-			prev_image = image
-		elseif string.match(image.exif_datetime_taken, '[%d]') ~= nil then --make sure current image has a timestamp, if so check if it is within the user specified gap value and add to group
-			local curr_image = image
-			if GetTimeDiff(curr_image, prev_image) <= GUI.gap.value then
-				images[i]:group_with(images[i-1])
-			end
-			prev_image = curr_image
-		end
-	end
+    local images = {}
+    if on_collection then 
+        local col_images = dt.collection
+        for i,image in ipairs(col_images) do --copy images to a standard table, table.sort barfs on type dt_lua_singleton_image_collection
+            table.insert(images,i,image)
+        end
+    else
+        images = dt.gui.selection()
+    end
+    dt.preferences.write(MOD, 'active_gap', 'integer', GUI.gap.value)
+    if #images < 2 then 
+        dt.print('please select at least 2 images')
+        return
+    end
+    table.sort(images, function(first, second) return CompTime(first,second) end)  --sort images by timestamp
+    
+    for i, image in ipairs(images) do
+        if i == 1 then 
+            prev_image = image
+        elseif string.match(image.exif_datetime_taken, '[%d]') ~= nil then --make sure current image has a timestamp, if so check if it is within the user specified gap value and add to group
+            local curr_image = image
+            if GetTimeDiff(curr_image, prev_image) <= GUI.gap.value then
+                images[i]:group_with(images[i-1])
+            end
+            prev_image = curr_image
+        end
+    end
 end
 
 -- GUI --
 GUI = {
-	gap = 			{},
-	selected = 		{},
-	collection = 	{}
+    gap =           {},
+    selected =      {},
+    collection =    {}
 }
-temp = dt.preferences.read(mod, 'active_gap', 'integer')
-if not InRange(temp, 1, 3600) then temp = 3 end
+temp = dt.preferences.read(MOD, 'active_gap', 'integer')
+if not InRange(temp, 1, 86400) then temp = 3 end
 GUI.gap = dt.new_widget('slider'){
-	label = _('group gap [sec.]'),
-	tooltip = _('minimum gap, in seconds, between groups'),
-	soft_min = 1,
-	soft_max = 30,
-	hard_min = 1,
-	hard_max = 3600,
-	step = 1,
-	digits = 0,
-	value = temp,
-	reset_callback = function(self) 
-		self.value = 3
-	end
+    label = _('group gap [sec.]'),
+    tooltip = _('minimum gap, in seconds, between groups'),
+    soft_min = 1,
+    soft_max = 60,
+    hard_min = 1,
+    hard_max = 86400,
+    step = 1,
+    digits = 0,
+    value = temp,
+    reset_callback = function(self) 
+        self.value = 3
+    end
 }
 GUI.selected = dt.new_widget("button"){
-	label = _('auto group: selected'),
-	tooltip =_('auto group selected images'),
-	clicked_callback = function() main(false) end
+    label = _('auto group: selected'),
+    tooltip =_('auto group selected images'),
+    clicked_callback = function() main(false) end
 }
 GUI.collection = dt.new_widget("button"){
-	label = _('auto group: collection'),
-	tooltip =_('auto group the entire collection'),
-	clicked_callback = function() main(true) end
+    label = _('auto group: collection'),
+    tooltip =_('auto group the entire collection'),
+    clicked_callback = function() main(true) end
 }
 dt.register_lib(
-	"AutoGroup_Lib",	-- Module name
-	_("Auto Group"),	-- name
-	true,	-- expandable
-	true,	-- resetable
-	{[dt.gui.views.lighttable] = {"DT_UI_CONTAINER_PANEL_RIGHT_CENTER", 99}},	-- containers
-	dt.new_widget("box"){
-		orientation = "vertical",
-		GUI.gap,
-		GUI.selected,
-		GUI.collection
-		}
+    'AutoGroup_Lib',    -- Module name
+    _('auto group'),    -- name
+    true,   -- expandable
+    true,   -- resetable
+    {[dt.gui.views.lighttable] = {"DT_UI_CONTAINER_PANEL_RIGHT_CENTER", 99}},   -- containers
+    dt.new_widget("box"){
+        orientation = "vertical",
+        GUI.gap,
+        GUI.selected,
+        GUI.collection
+        }
 )