Replace HistoryChart by new Kotlin implementation

android/uhabits-core/src/main/java/org/isoron/platform/gui/Canvas.kt

@@ -34,6 +34,7 @@ interface Canvas {
     fun drawLine(x1: Double, y1: Double, x2: Double, y2: Double)
     fun drawText(text: String, x: Double, y: Double)
     fun fillRect(x: Double, y: Double, width: Double, height: Double)
+    fun fillRoundRect(x: Double, y: Double, width: Double, height: Double, cornerRadius: Double)
     fun drawRect(x: Double, y: Double, width: Double, height: Double)
     fun getHeight(): Double
     fun getWidth(): Double

android/uhabits-core/src/main/java/org/isoron/platform/gui/Color.kt

@@ -19,8 +19,6 @@
 
 package org.isoron.platform.gui
 
-data class PaletteColor(val index: Int)
-
 data class Color(
     val red: Double,
     val green: Double,
@@ -48,4 +46,11 @@ data class Color(
             alpha * (1 - weight) + other.alpha * weight
         )
     }
+
+    fun contrast(other: Color): Double {
+        val l1 = this.luminosity
+        val l2 = other.luminosity
+        val relativeLuminosity = (l1 + 0.05) / (l2 + 0.05)
+        return if (relativeLuminosity >= 1) relativeLuminosity else 1 / relativeLuminosity
+    }
 }

android/uhabits-core/src/main/java/org/isoron/platform/gui/JavaCanvas.kt

@@ -30,6 +30,7 @@ import java.awt.RenderingHints.VALUE_ANTIALIAS_ON
 import java.awt.RenderingHints.VALUE_FRACTIONALMETRICS_ON
 import java.awt.RenderingHints.VALUE_TEXT_ANTIALIAS_ON
 import java.awt.font.FontRenderContext
+import java.awt.geom.RoundRectangle2D
 import java.awt.image.BufferedImage
 import kotlin.math.roundToInt
 
@@ -115,6 +116,25 @@ class JavaCanvas(
         g2d.fillRect(toPixel(x), toPixel(y), toPixel(width), toPixel(height))
     }
 
+    override fun fillRoundRect(
+        x: Double,
+        y: Double,
+        width: Double,
+        height: Double,
+        cornerRadius: Double
+    ) {
+        g2d.fill(
+            RoundRectangle2D.Double(
+                toPixel(x).toDouble(),
+                toPixel(y).toDouble(),
+                toPixel(width).toDouble(),
+                toPixel(height).toDouble(),
+                toPixel(cornerRadius).toDouble(),
+                toPixel(cornerRadius).toDouble(),
+            )
+        )
+    }
+
     override fun drawRect(x: Double, y: Double, width: Double, height: Double) {
         g2d.drawRect(toPixel(x), toPixel(y), toPixel(width), toPixel(height))
     }

android/uhabits-core/src/main/java/org/isoron/uhabits/core/ui/screens/habits/show/ShowHabit.kt

@@ -96,6 +96,7 @@ class ShowHabitPresenter {
                 habit = habit,
                 firstWeekday = preferences.firstWeekday,
                 isSkipEnabled = preferences.isSkipEnabled,
+                theme = theme,
             ),
             bar = BarCardPresenter().present(
                 habit = habit,

android/uhabits-core/src/main/java/org/isoron/uhabits/core/ui/screens/habits/show/views/HistoryCard.kt

@@ -19,16 +19,24 @@
 
 package org.isoron.uhabits.core.ui.screens.habits.show.views
 
+import org.isoron.platform.time.LocalDate
+import org.isoron.uhabits.core.models.Entry
+import org.isoron.uhabits.core.models.Entry.Companion.SKIP
+import org.isoron.uhabits.core.models.Entry.Companion.YES_AUTO
+import org.isoron.uhabits.core.models.Entry.Companion.YES_MANUAL
 import org.isoron.uhabits.core.models.Habit
 import org.isoron.uhabits.core.models.PaletteColor
+import org.isoron.uhabits.core.ui.views.HistoryChart
+import org.isoron.uhabits.core.ui.views.Theme
 import org.isoron.uhabits.core.utils.DateUtils
+import kotlin.math.max
 
 data class HistoryCardViewModel(
     val color: PaletteColor,
-    val entries: IntArray,
     val firstWeekday: Int,
-    val isNumerical: Boolean,
-    val isSkipEnabled: Boolean,
+    val series: List<HistoryChart.Square>,
+    val theme: Theme,
+    val today: LocalDate,
 )
 
 class HistoryCardPresenter {
@@ -36,18 +44,37 @@ class HistoryCardPresenter {
         habit: Habit,
         firstWeekday: Int,
         isSkipEnabled: Boolean,
+        theme: Theme,
     ): HistoryCardViewModel {
         val today = DateUtils.getTodayWithOffset()
         val oldest = habit.computedEntries.getKnown().lastOrNull()?.timestamp ?: today
-        val entries =
-            habit.computedEntries.getByInterval(oldest, today).map { it.value }.toIntArray()
+        val entries = habit.computedEntries.getByInterval(oldest, today)
+        val series = if (habit.isNumerical) {
+            entries.map {
+                Entry(it.timestamp, max(0, it.value))
+            }.map {
+                when (it.value) {
+                    0 -> HistoryChart.Square.OFF
+                    else -> HistoryChart.Square.ON
+                }
+            }
+        } else {
+            entries.map {
+                when (it.value) {
+                    YES_MANUAL -> HistoryChart.Square.ON
+                    YES_AUTO -> HistoryChart.Square.DIMMED
+                    SKIP -> HistoryChart.Square.HATCHED
+                    else -> HistoryChart.Square.OFF
+                }
+            }
+        }
 
         return HistoryCardViewModel(
-            entries = entries,
             color = habit.color,
             firstWeekday = firstWeekday,
-            isNumerical = habit.isNumerical,
-            isSkipEnabled = isSkipEnabled,
+            today = today.toLocalDate(),
+            theme = theme,
+            series = series,
         )
     }
 }

android/uhabits-core/src/main/java/org/isoron/uhabits/core/ui/views/HistoryChart.kt

@@ -21,53 +21,74 @@ package org.isoron.uhabits.core.ui.views
 
 import org.isoron.platform.gui.Canvas
 import org.isoron.platform.gui.Color
+import org.isoron.platform.gui.DataView
 import org.isoron.platform.gui.TextAlign
-import org.isoron.platform.gui.View
 import org.isoron.platform.time.LocalDate
 import org.isoron.platform.time.LocalDateFormatter
+import org.isoron.uhabits.core.models.PaletteColor
 import kotlin.math.floor
 import kotlin.math.round
 
-class CalendarChart(
+class HistoryChart(
     var today: LocalDate,
-    var color: Color,
+    var paletteColor: PaletteColor,
     var theme: Theme,
     var dateFormatter: LocalDateFormatter
-) : View {
+) : DataView {
 
-    var padding = 5.0
-    var backgroundColor = Color(0xFFFFFF)
+    enum class Square {
+        ON,
+        OFF,
+        DIMMED,
+        HATCHED,
+    }
+
+    // Data
+    var series = listOf<Square>()
+
+    // Style
+    var padding = 0.0
     var squareSpacing = 1.0
-    var series = listOf<Double>()
-    var scrollPosition = 0
+    override var dataOffset = 0
     private var squareSize = 0.0
 
+    var lastPrintedMonth = ""
+    var lastPrintedYear = ""
+
+    override val dataColumnWidth: Double
+        get() = squareSpacing + squareSize
+
     override fun draw(canvas: Canvas) {
         val width = canvas.getWidth()
         val height = canvas.getHeight()
-        canvas.setColor(backgroundColor)
+        canvas.setColor(theme.cardBackgroundColor)
         canvas.fillRect(0.0, 0.0, width, height)
         squareSize = round((height - 2 * padding) / 8.0)
         canvas.setFontSize(height * 0.06)
 
         val nColumns = floor((width - 2 * padding) / squareSize).toInt() - 2
         val todayWeekday = today.dayOfWeek
-        val topLeftOffset = (nColumns - 1 + scrollPosition) * 7 + todayWeekday.index
+        val topLeftOffset = (nColumns - 1 + dataOffset) * 7 + todayWeekday.index
         val topLeftDate = today.minus(topLeftOffset)
 
+        lastPrintedYear = ""
+        lastPrintedMonth = ""
+
+        // Draw main columns
         repeat(nColumns) { column ->
             val topOffset = topLeftOffset - 7 * column
             val topDate = topLeftDate.plus(7 * column)
             drawColumn(canvas, column, topDate, topOffset)
         }
 
+        // Draw week day names
         canvas.setColor(theme.mediumContrastTextColor)
         repeat(7) { row ->
             val date = topLeftDate.plus(row)
             canvas.setTextAlign(TextAlign.LEFT)
             canvas.drawText(
                 dateFormatter.shortWeekdayName(date),
-                padding + nColumns * squareSize + padding,
+                padding + nColumns * squareSize + squareSpacing * 3,
                 padding + squareSize * (row + 1) + squareSize / 2
             )
         }
@@ -97,22 +118,29 @@ class CalendarChart(
     }
 
     private fun drawHeader(canvas: Canvas, column: Int, date: LocalDate) {
-        if (date.day >= 8) return
-
         canvas.setColor(theme.mediumContrastTextColor)
-        if (date.month == 1) {
-            canvas.drawText(
-                date.year.toString(),
-                padding + column * squareSize + squareSize / 2,
-                padding + squareSize / 2
-            )
-        } else {
-            canvas.drawText(
-                dateFormatter.shortMonthName(date),
-                padding + column * squareSize + squareSize / 2,
-                padding + squareSize / 2
-            )
+        val monthText = dateFormatter.shortMonthName(date)
+        val yearText = date.year.toString()
+        val headerText: String
+        when {
+            monthText != lastPrintedMonth -> {
+                headerText = monthText
+                lastPrintedMonth = monthText
+            }
+            yearText != lastPrintedYear -> {
+                headerText = yearText
+                lastPrintedYear = headerText
+            }
+            else -> {
+                headerText = ""
+            }
         }
+        canvas.setTextAlign(TextAlign.LEFT)
+        canvas.drawText(
+            headerText,
+            padding + column * squareSize,
+            padding + squareSize / 2
+        )
     }
 
     private fun drawSquare(
@@ -125,19 +153,46 @@ class CalendarChart(
         offset: Int
     ) {
 
-        var value = if (offset >= series.size) 0.0 else series[offset]
-        value = round(value * 5.0) / 5.0
-
-        var squareColor = color.blendWith(backgroundColor, 1 - value)
-        var textColor = backgroundColor
-
-        if (value == 0.0) squareColor = theme.lowContrastTextColor
-        if (squareColor.luminosity > 0.8)
-            textColor = squareColor.blendWith(theme.highContrastTextColor, 0.5)
+        val value = if (offset >= series.size) Square.OFF else series[offset]
+        val squareColor: Color
+        val color = theme.color(paletteColor.paletteIndex)
+        when (value) {
+            Square.ON -> {
+                squareColor = color
+            }
+            Square.OFF -> {
+                squareColor = theme.lowContrastTextColor
+            }
+            Square.DIMMED, Square.HATCHED -> {
+                squareColor = color.blendWith(theme.cardBackgroundColor, 0.5)
+            }
+        }
 
         canvas.setColor(squareColor)
-        canvas.fillRect(x, y, width, height)
+        canvas.fillRoundRect(x, y, width, height, width * 0.15)
+
+        if (value == Square.HATCHED) {
+            canvas.setStrokeWidth(0.75)
+            canvas.setColor(theme.cardBackgroundColor)
+            var k = width / 10
+            repeat(5) {
+                canvas.drawLine(x + k, y, x, y + k)
+                canvas.drawLine(
+                    x + width - k,
+                    y + height,
+                    x + width,
+                    y + height - k
+                )
+                k += width / 5
+            }
+        }
+
+        val c1 = squareColor.contrast(theme.cardBackgroundColor)
+        val c2 = squareColor.contrast(theme.mediumContrastTextColor)
+        val textColor = if (c1 > c2) theme.cardBackgroundColor else theme.mediumContrastTextColor
+
         canvas.setColor(textColor)
+        canvas.setTextAlign(TextAlign.CENTER)
         canvas.drawText(date.day.toString(), x + width / 2, y + width / 2)
     }
 }

android/uhabits-core/src/test/java/org/isoron/uhabits/core/ui/views/HistoryChartTest.kt

@@ -0,0 +1,100 @@
+/*
+ * Copyright (C) 2016-2019 Álinson Santos Xavier <isoron@gmail.com>
+ *
+ * This file is part of Loop Habit Tracker.
+ *
+ * Loop Habit Tracker is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ *
+ * Loop Habit Tracker is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package org.isoron.uhabits.components
+
+import kotlinx.coroutines.runBlocking
+import org.isoron.platform.gui.assertRenders
+import org.isoron.platform.time.JavaLocalDateFormatter
+import org.isoron.platform.time.LocalDate
+import org.isoron.uhabits.core.models.PaletteColor
+import org.isoron.uhabits.core.ui.views.DarkTheme
+import org.isoron.uhabits.core.ui.views.HistoryChart
+import org.isoron.uhabits.core.ui.views.HistoryChart.Square.DIMMED
+import org.isoron.uhabits.core.ui.views.HistoryChart.Square.HATCHED
+import org.isoron.uhabits.core.ui.views.HistoryChart.Square.OFF
+import org.isoron.uhabits.core.ui.views.HistoryChart.Square.ON
+import org.isoron.uhabits.core.ui.views.LightTheme
+import org.junit.Test
+import java.util.Locale
+
+class HistoryChartTest {
+    val base = "views/HistoryChart"
+    val fmt = JavaLocalDateFormatter(Locale.US)
+    val theme = LightTheme()
+    val view = HistoryChart(
+        LocalDate(2015, 1, 25),
+        PaletteColor(7),
+        theme,
+        fmt,
+    ).apply {
+        series = listOf(
+            2, // today
+            2, 1, 2, 1, 2, 1, 2,
+            2, 3, 3, 3, 3, 1, 2,
+            2, 1, 2, 1, 2, 2, 1,
+            1, 1, 1, 1, 2, 2, 2,
+            1, 3, 3, 3, 0, 0, 0,
+            0, 0, 0, 0, 0, 0, 0,
+            0, 0, 0, 1, 1, 1, 1,
+            2, 2, 2, 3, 3, 3, 1,
+            1, 2, 1, 2, 1, 1, 2,
+            1, 2, 1, 1, 1, 1, 2,
+            2, 2, 2, 2, 2, 1, 1,
+            1, 1, 2, 2, 1, 2, 1,
+            1, 1, 1, 1, 2, 2, 2,
+        ).map {
+            when (it) {
+                3 -> HATCHED
+                2 -> ON
+                1 -> DIMMED
+                else -> OFF
+            }
+        }
+    }
+
+    // TODO: Label overflow
+    // TODO: Transparent
+    // TODO: onClick
+    // TODO: HistoryEditorDialog
+    // TODO: Remove excessive padding on widgets
+    // TODO: First day of the week
+
+    @Test
+    fun testDraw() = runBlocking {
+        assertRenders(400, 200, "$base/base.png", view)
+    }
+
+    @Test
+    fun testDrawDifferentSize() = runBlocking {
+        assertRenders(200, 200, "$base/small.png", view)
+    }
+
+    @Test
+    fun testDrawDarkTheme() = runBlocking {
+        view.theme = DarkTheme()
+        assertRenders(400, 200, "$base/dark.png", view)
+    }
+
+    @Test
+    fun testDrawOffset() = runBlocking {
+        view.dataOffset = 2
+        assertRenders(400, 200, "$base/scroll.png", view)
+    }
+}