add option to show temperature in both units

Separate options for the widget itself, and in the popup.

Also note that this changes the precision slightly:
* on the widget itself: now uses string formatting to round, instead of removing the decimal
* on the popup: rounds to 1 decimal place in popup (was showing 2 decimal places before)

2 files changed, 47 insertions, 7 deletions

diff --git a/secrets.lua b/secrets.lua
index 19f35b8..ab87b9f 100644
--- a/secrets.lua
+++ b/secrets.lua
@@ -5,6 +5,15 @@
 -- @copyright 2019 Pavel Makhov
 --------------------------------------------
 
+local function getenv_bool(var_name, default_val)
+    val = os.getenv(var_name)
+    if val ~= nil then
+        return val:lower() == 'true'
+    else
+        return default_val
+    end
+end
+
 local secrets = {
     -- Yandex.Translate API key - https://tech.yandex.com/translate/
     translate_widget_api_key = os.getenv('AWW_TRANSLATE_API_KEY') or 'API_KEY',
@@ -12,7 +21,9 @@ local secrets = {
     -- OpenWeatherMap API key - https://openweathermap.org/appid
     weather_widget_api_key = os.getenv('AWW_WEATHER_API_KEY') or 'API_KEY',
     weather_widget_city = os.getenv('AWW_WEATHER_CITY') or 'Montreal,ca',
-    weather_widget_units = os.getenv('AWW_WEATHER_UNITS') or 'metric' -- for celsius, or 'imperial' for fahrenheit
+    weather_widget_units = os.getenv('AWW_WEATHER_UNITS') or 'metric', -- for celsius, or 'imperial' for fahrenheit
+    weather_both_temp_units_widget = getenv_bool('AWW_WEATHER_BOTH_UNITS_WIDGET', false), -- on widget, if true shows "22 C (72 F)", instead of only "22 C"
+    weather_both_temp_units_popup = getenv_bool('AWW_WEATHER_BOTH_UNITS_POPUP', true) -- in the popup, if true shows "22.3 C (72.2 F)" instead of only "22.3 C"
 }
 
 return secrets
diff --git a/weather-widget/weather.lua b/weather-widget/weather.lua
index 2d80947..d6693cf 100644
--- a/weather-widget/weather.lua
+++ b/weather-widget/weather.lua
@@ -98,9 +98,39 @@ local function to_direction(degrees)
     return directions[math.floor((degrees % 360) / 22.5) + 1]
 end
 
+-- Convert degrees Celsius to Fahrenheit
+local function celsius_to_fahrenheit(c)
+    return c*9/5+32
+end
+
+-- Convert degrees Fahrenheit to Celsius
+local function fahrenheit_to_celsius(f)
+    return (f-32)*5/9
+end
+
 local weather_timer = gears.timer({ timeout = 60 })
 local resp
 
+local function gen_temperature_str(temp, fmt_str, show_other_units)
+    local temp_str = string.format(fmt_str, temp)
+    local s =  temp_str .. '°' .. (secrets.weather_widget_units == 'metric' and 'C' or 'F')
+
+    if (show_other_units) then
+        local temp_conv, units_conv
+        if (secrets.weather_widget_units == 'metric') then
+            temp_conv = celsius_to_fahrenheit(temp)
+            units_conv = 'F'
+        else
+            temp_conv = fahrenheit_to_celsius(temp)
+            units_conv = 'C'
+        end
+
+        local temp_conv_str = string.format(fmt_str, temp_conv)
+        s = s .. ' ' ..  '('.. temp_conv_str .. '°' .. units_conv .. ')'
+    end
+    return s
+end
+
 weather_timer:connect_signal("timeout", function ()
     local resp_json = {}
     local res, status = http.request{
@@ -132,9 +162,8 @@ weather_timer:connect_signal("timeout", function ()
     elseif (resp_json ~= nil and resp_json ~= '') then
         resp = json.decode(resp_json)
         icon_widget.image = path_to_icons .. icon_map[resp.weather[1].icon]
-        temp_widget:set_text(string.gsub(resp.main.temp, "%.%d+", "")
-                .. '°'
-                .. (secrets.weather_widget_units == 'metric' and 'C' or 'F'))
+        temp_widget:set_text(gen_temperature_str(resp.main.temp, '%.0f',
+                                 secrets.weather_both_temp_units_widget))
     end
 end)
 weather_timer:start()
@@ -149,13 +178,13 @@ weather_widget:connect_signal("mouse::enter", function()
         text =
             '<big>' .. resp.weather[1].main .. ' (' .. resp.weather[1].description .. ')</big><br>' ..
             '<b>Humidity:</b> ' .. resp.main.humidity .. '%<br>' ..
-            '<b>Temperature:</b> ' .. resp.main.temp .. '°'
-                    .. (secrets.weather_widget_units == 'metric' and 'C' or 'F') .. '<br>' ..
+            '<b>Temperature:</b> ' .. gen_temperature_str(resp.main.temp, '%.1f',
+                                          secrets.weather_both_temp_units_popup) .. '<br>' ..
             '<b>Pressure:</b> ' .. resp.main.pressure .. 'hPa<br>' ..
             '<b>Clouds:</b> ' .. resp.clouds.all .. '%<br>' ..
             '<b>Wind:</b> ' .. resp.wind.speed .. 'm/s (' .. to_direction(resp.wind.deg) .. ')',
         timeout = 5, hover_timeout = 10,
-        width = 200
+        width = (secrets.weather_both_temp_units_popup == true and 210 or 200)
     }
 end)