From 106739720573a348750ca87bb5c4517fd8cf9344 Mon Sep 17 00:00:00 2001
From: MM20 <15646950+MM2-0@users.noreply.github.com>
Date: Sun, 12 Dec 2021 22:05:36 +0100
Subject: [PATCH] Add unit converter for units of temperature

---
 .../launcher2/search/data/UnitConverter.kt    |   3 +-
 .../converters/SimpleFactorConverter.kt       |   7 +-
 .../converters/TemperatureConverter.kt        | 112 +++++++++++++++++-
 3 files changed, 116 insertions(+), 6 deletions(-)

diff --git a/unitconverter/src/main/java/de/mm20/launcher2/search/data/UnitConverter.kt b/unitconverter/src/main/java/de/mm20/launcher2/search/data/UnitConverter.kt
index 8eee3144..972d6065 100644
--- a/unitconverter/src/main/java/de/mm20/launcher2/search/data/UnitConverter.kt
+++ b/unitconverter/src/main/java/de/mm20/launcher2/search/data/UnitConverter.kt
@@ -35,7 +35,8 @@ open class UnitConverter(
                     lazy { DataConverter(context) },
                     lazy { TimeConverter(context) },
                     lazy { VelocityConverter(context) },
-                    lazy { AreaConverter(context) }
+                    lazy { AreaConverter(context) },
+                    lazy { TemperatureConverter(context) }
             )
             for (conv in converters) {
                 val converter = conv.value
diff --git a/unitconverter/src/main/java/de/mm20/launcher2/unitconverter/converters/SimpleFactorConverter.kt b/unitconverter/src/main/java/de/mm20/launcher2/unitconverter/converters/SimpleFactorConverter.kt
index a17d7490..ce47bd8a 100644
--- a/unitconverter/src/main/java/de/mm20/launcher2/unitconverter/converters/SimpleFactorConverter.kt
+++ b/unitconverter/src/main/java/de/mm20/launcher2/unitconverter/converters/SimpleFactorConverter.kt
@@ -3,6 +3,7 @@ package de.mm20.launcher2.unitconverter.converters
 import android.content.Context
 import de.mm20.launcher2.search.data.UnitConverter
 import de.mm20.launcher2.unitconverter.ConverterUtils
+import de.mm20.launcher2.unitconverter.MeasureUnit
 import de.mm20.launcher2.unitconverter.UnitValue
 
 /**
@@ -40,6 +41,6 @@ abstract class SimpleFactorConverter: Converter {
 
 data class MeasureUnitWithFactor(
     val factor: Double,
-    val symbol: String,
-    val nameResource: Int
-)
\ No newline at end of file
+    override val symbol: String,
+    override val nameResource: Int
+): MeasureUnit
\ No newline at end of file
diff --git a/unitconverter/src/main/java/de/mm20/launcher2/unitconverter/converters/TemperatureConverter.kt b/unitconverter/src/main/java/de/mm20/launcher2/unitconverter/converters/TemperatureConverter.kt
index a3bfa78e..00eca44b 100644
--- a/unitconverter/src/main/java/de/mm20/launcher2/unitconverter/converters/TemperatureConverter.kt
+++ b/unitconverter/src/main/java/de/mm20/launcher2/unitconverter/converters/TemperatureConverter.kt
@@ -1,8 +1,116 @@
 package de.mm20.launcher2.unitconverter.converters
 
 import android.content.Context
-import de.mm20.launcher2.unitconverter.Dimension
+import de.mm20.launcher2.search.data.UnitConverter
+import de.mm20.launcher2.unitconverter.*
 
-class TemperatureConverter(context: Context): SimpleFactorConverter() {
+class TemperatureConverter(context: Context) : Converter {
     override val dimension = Dimension.Temperature
+
+    private val units = listOf(
+        TemperatureMeasureUnit(
+            context.getString(R.string.unit_degree_celsius_symbol),
+            R.plurals.unit_degree_celsius,
+            TemperatureUnit.DegreeCelsius
+        ),
+        TemperatureMeasureUnit(
+            context.getString(R.string.unit_degree_fahrenheit_symbol),
+            R.plurals.unit_degree_fahrenheit,
+            TemperatureUnit.DegreeFahrenheit
+        ),
+        TemperatureMeasureUnit(
+            context.getString(R.string.unit_kelvin_symbol),
+            R.plurals.unit_kelvin,
+            TemperatureUnit.Kelvin
+        ),
+    )
+
+    override suspend fun isValidUnit(symbol: String): Boolean {
+        return units.any { it.symbol == symbol }
+    }
+
+    override suspend fun convert(
+        context: Context,
+        fromUnit: String,
+        value: Double,
+        toUnit: String?
+    ): UnitConverter {
+        val from = units.first { it.symbol == fromUnit }
+        val to = toUnit?.let { unit -> units.first { it.symbol == unit } }
+
+        val values = mutableListOf<UnitValue>()
+
+        if (to != null) {
+            val toValue = convertTemperature(value, from.unit, to.unit)
+
+            values += UnitValue(
+                value = value,
+                symbol = toUnit,
+                formattedName = ConverterUtils.formatName(context, to, toValue),
+                formattedValue = ConverterUtils.formatValue(context, to, toValue),
+            )
+        } else {
+            for (to in units) {
+                if (to.symbol == from.symbol) continue
+                val v = convertTemperature(value, from.unit, to.unit)
+                values += UnitValue(
+                    v,
+                    to.symbol,
+                    ConverterUtils.formatName(context, to, v),
+                    ConverterUtils.formatValue(context, to, v)
+                )
+            }
+        }
+        return UnitConverter(
+            dimension = Dimension.Temperature,
+            inputValue = UnitValue(
+                value = value,
+                symbol = fromUnit,
+                formattedName = ConverterUtils.formatName(context, from, value),
+                formattedValue = ConverterUtils.formatValue(context, from, value),
+            ),
+            values = values
+        )
+    }
+
+    private fun convertTemperature(
+        value: Double,
+        from: TemperatureUnit,
+        to: TemperatureUnit
+    ): Double {
+        if (from == to) return value
+        if (from == TemperatureUnit.Kelvin && to == TemperatureUnit.DegreeCelsius) {
+            return value - 273.15
+        }
+        if (from == TemperatureUnit.DegreeCelsius && to == TemperatureUnit.Kelvin) {
+            return value + 273.15
+        }
+        if (from === TemperatureUnit.DegreeCelsius && to == TemperatureUnit.DegreeFahrenheit) {
+            return value * (9.0 / 5.0) + 32.0
+        }
+        if (from === TemperatureUnit.DegreeFahrenheit && to == TemperatureUnit.DegreeCelsius) {
+            return (value - 32.0) * (5.0 / 9.0)
+        }
+
+        if (from === TemperatureUnit.Kelvin && to == TemperatureUnit.DegreeFahrenheit) {
+            return (value - 273.15) * (9.0 / 5.0) + 32.0
+        }
+        if (from === TemperatureUnit.DegreeFahrenheit && to == TemperatureUnit.Kelvin) {
+            return (value - 32.0) * (5.0 / 9.0) + 273.15
+        }
+        throw IllegalArgumentException()
+    }
+}
+
+private data class TemperatureMeasureUnit(
+    override val symbol: String,
+    override val nameResource: Int,
+    val unit: TemperatureUnit
+) :
+    MeasureUnit
+
+private enum class TemperatureUnit {
+    DegreeCelsius,
+    DegreeFahrenheit,
+    Kelvin,
 }
\ No newline at end of file