6 files changed, 539 insertions, 0 deletions
diff --git a/src/components/Toast/Toast.tsx b/src/components/Toast/Toast.tsx
new file mode 100644
index 000000000..0dc9d4b07
--- /dev/null
+++ b/src/components/Toast/Toast.tsx
@@ -0,0 +1,205 @@
+import {createContext, useContext, useMemo} from 'react'
+import {View} from 'react-native'
+
+import {atoms as a, select, useTheme} from '#/alf'
+import {Check_Stroke2_Corner0_Rounded as SuccessIcon} from '#/components/icons/Check'
+import {CircleInfo_Stroke2_Corner0_Rounded as CircleInfo} from '#/components/icons/CircleInfo'
+import {CircleInfo_Stroke2_Corner0_Rounded as ErrorIcon} from '#/components/icons/CircleInfo'
+import {Warning_Stroke2_Corner0_Rounded as WarningIcon} from '#/components/icons/Warning'
+import {type ToastType} from '#/components/Toast/types'
+import {Text} from '#/components/Typography'
+
+type ContextType = {
+  type: ToastType
+}
+
+export const ICONS = {
+  default: SuccessIcon,
+  success: SuccessIcon,
+  error: ErrorIcon,
+  warning: WarningIcon,
+  info: CircleInfo,
+}
+
+const Context = createContext<ContextType>({
+  type: 'default',
+})
+
+export function Toast({
+  type,
+  content,
+}: {
+  type: ToastType
+  content: React.ReactNode
+}) {
+  const t = useTheme()
+  const styles = useToastStyles({type})
+  const Icon = ICONS[type]
+
+  return (
+    <Context.Provider value={useMemo(() => ({type}), [type])}>
+      <View
+        style={[
+          a.flex_1,
+          a.py_lg,
+          a.pl_xl,
+          a.pr_2xl,
+          a.rounded_md,
+          a.border,
+          a.flex_row,
+          a.gap_sm,
+          t.atoms.shadow_sm,
+          {
+            backgroundColor: styles.backgroundColor,
+            borderColor: styles.borderColor,
+          },
+        ]}>
+        <Icon size="md" fill={styles.iconColor} />
+
+        <View style={[a.flex_1]}>
+          {typeof content === 'string' ? (
+            <ToastText>{content}</ToastText>
+          ) : (
+            content
+          )}
+        </View>
+      </View>
+    </Context.Provider>
+  )
+}
+
+export function ToastText({children}: {children: React.ReactNode}) {
+  const {type} = useContext(Context)
+  const {textColor} = useToastStyles({type})
+  return (
+    <Text
+      style={[
+        a.text_md,
+        a.font_bold,
+        a.leading_snug,
+        {
+          color: textColor,
+        },
+      ]}>
+      {children}
+    </Text>
+  )
+}
+
+function useToastStyles({type}: {type: ToastType}) {
+  const t = useTheme()
+  return useMemo(() => {
+    return {
+      default: {
+        backgroundColor: select(t.name, {
+          light: t.atoms.bg_contrast_25.backgroundColor,
+          dim: t.atoms.bg_contrast_100.backgroundColor,
+          dark: t.atoms.bg_contrast_100.backgroundColor,
+        }),
+        borderColor: select(t.name, {
+          light: t.atoms.border_contrast_low.borderColor,
+          dim: t.atoms.border_contrast_high.borderColor,
+          dark: t.atoms.border_contrast_high.borderColor,
+        }),
+        iconColor: select(t.name, {
+          light: t.atoms.text_contrast_medium.color,
+          dim: t.atoms.text_contrast_medium.color,
+          dark: t.atoms.text_contrast_medium.color,
+        }),
+        textColor: select(t.name, {
+          light: t.atoms.text_contrast_medium.color,
+          dim: t.atoms.text_contrast_medium.color,
+          dark: t.atoms.text_contrast_medium.color,
+        }),
+      },
+      success: {
+        backgroundColor: select(t.name, {
+          light: t.palette.primary_100,
+          dim: t.palette.primary_100,
+          dark: t.palette.primary_50,
+        }),
+        borderColor: select(t.name, {
+          light: t.palette.primary_500,
+          dim: t.palette.primary_500,
+          dark: t.palette.primary_500,
+        }),
+        iconColor: select(t.name, {
+          light: t.palette.primary_500,
+          dim: t.palette.primary_600,
+          dark: t.palette.primary_600,
+        }),
+        textColor: select(t.name, {
+          light: t.palette.primary_500,
+          dim: t.palette.primary_600,
+          dark: t.palette.primary_600,
+        }),
+      },
+      error: {
+        backgroundColor: select(t.name, {
+          light: t.palette.negative_200,
+          dim: t.palette.negative_25,
+          dark: t.palette.negative_25,
+        }),
+        borderColor: select(t.name, {
+          light: t.palette.negative_300,
+          dim: t.palette.negative_300,
+          dark: t.palette.negative_300,
+        }),
+        iconColor: select(t.name, {
+          light: t.palette.negative_600,
+          dim: t.palette.negative_600,
+          dark: t.palette.negative_600,
+        }),
+        textColor: select(t.name, {
+          light: t.palette.negative_600,
+          dim: t.palette.negative_600,
+          dark: t.palette.negative_600,
+        }),
+      },
+      warning: {
+        backgroundColor: select(t.name, {
+          light: t.atoms.bg_contrast_25.backgroundColor,
+          dim: t.atoms.bg_contrast_100.backgroundColor,
+          dark: t.atoms.bg_contrast_100.backgroundColor,
+        }),
+        borderColor: select(t.name, {
+          light: t.atoms.border_contrast_low.borderColor,
+          dim: t.atoms.border_contrast_high.borderColor,
+          dark: t.atoms.border_contrast_high.borderColor,
+        }),
+        iconColor: select(t.name, {
+          light: t.atoms.text_contrast_medium.color,
+          dim: t.atoms.text_contrast_medium.color,
+          dark: t.atoms.text_contrast_medium.color,
+        }),
+        textColor: select(t.name, {
+          light: t.atoms.text_contrast_medium.color,
+          dim: t.atoms.text_contrast_medium.color,
+          dark: t.atoms.text_contrast_medium.color,
+        }),
+      },
+      info: {
+        backgroundColor: select(t.name, {
+          light: t.atoms.bg_contrast_25.backgroundColor,
+          dim: t.atoms.bg_contrast_100.backgroundColor,
+          dark: t.atoms.bg_contrast_100.backgroundColor,
+        }),
+        borderColor: select(t.name, {
+          light: t.atoms.border_contrast_low.borderColor,
+          dim: t.atoms.border_contrast_high.borderColor,
+          dark: t.atoms.border_contrast_high.borderColor,
+        }),
+        iconColor: select(t.name, {
+          light: t.atoms.text_contrast_medium.color,
+          dim: t.atoms.text_contrast_medium.color,
+          dark: t.atoms.text_contrast_medium.color,
+        }),
+        textColor: select(t.name, {
+          light: t.atoms.text_contrast_medium.color,
+          dim: t.atoms.text_contrast_medium.color,
+          dark: t.atoms.text_contrast_medium.color,
+        }),
+      },
+    }[type]
+  }, [t, type])
+}
diff --git a/src/components/Toast/const.ts b/src/components/Toast/const.ts
new file mode 100644
index 000000000..034d0a2fc
--- /dev/null
+++ b/src/components/Toast/const.ts
@@ -0,0 +1 @@
+export const DEFAULT_TOAST_DURATION = 3000
diff --git a/src/components/Toast/index.e2e.tsx b/src/components/Toast/index.e2e.tsx
new file mode 100644
index 000000000..57daf5bf0
--- /dev/null
+++ b/src/components/Toast/index.e2e.tsx
@@ -0,0 +1,5 @@
+export function ToastContainer() {
+  return null
+}
+
+export function show() {}
diff --git a/src/components/Toast/index.tsx b/src/components/Toast/index.tsx
new file mode 100644
index 000000000..131a796b3
--- /dev/null
+++ b/src/components/Toast/index.tsx
@@ -0,0 +1,197 @@
+import {useEffect, useMemo, useRef, useState} from 'react'
+import {AccessibilityInfo} from 'react-native'
+import {
+  Gesture,
+  GestureDetector,
+  GestureHandlerRootView,
+} from 'react-native-gesture-handler'
+import Animated, {
+  Easing,
+  runOnJS,
+  SlideInUp,
+  SlideOutUp,
+  useAnimatedReaction,
+  useAnimatedStyle,
+  useSharedValue,
+  withDecay,
+  withSpring,
+} from 'react-native-reanimated'
+import RootSiblings from 'react-native-root-siblings'
+import {useSafeAreaInsets} from 'react-native-safe-area-context'
+
+import {useNonReactiveCallback} from '#/lib/hooks/useNonReactiveCallback'
+import {atoms as a} from '#/alf'
+import {DEFAULT_TOAST_DURATION} from '#/components/Toast/const'
+import {Toast} from '#/components/Toast/Toast'
+import {type ToastApi, type ToastType} from '#/components/Toast/types'
+
+const TOAST_ANIMATION_DURATION = 300
+
+export function ToastContainer() {
+  return null
+}
+
+export const toast: ToastApi = {
+  show(props) {
+    if (process.env.NODE_ENV === 'test') {
+      return
+    }
+
+    AccessibilityInfo.announceForAccessibility(props.a11yLabel)
+
+    const item = new RootSiblings(
+      (
+        <AnimatedToast
+          type={props.type}
+          content={props.content}
+          a11yLabel={props.a11yLabel}
+          duration={props.duration ?? DEFAULT_TOAST_DURATION}
+          destroy={() => item.destroy()}
+        />
+      ),
+    )
+  },
+}
+
+function AnimatedToast({
+  type,
+  content,
+  a11yLabel,
+  duration,
+  destroy,
+}: {
+  type: ToastType
+  content: React.ReactNode
+  a11yLabel: string
+  duration: number
+  destroy: () => void
+}) {
+  const {top} = useSafeAreaInsets()
+  const isPanning = useSharedValue(false)
+  const dismissSwipeTranslateY = useSharedValue(0)
+  const [cardHeight, setCardHeight] = useState(0)
+
+  // for the exit animation to work on iOS the animated component
+  // must not be the root component
+  // so we need to wrap it in a view and unmount the toast ahead of time
+  const [alive, setAlive] = useState(true)
+
+  const hideAndDestroyImmediately = () => {
+    setAlive(false)
+    setTimeout(() => {
+      destroy()
+    }, 1e3)
+  }
+
+  const destroyTimeoutRef = useRef<ReturnType<typeof setTimeout>>()
+  const hideAndDestroyAfterTimeout = useNonReactiveCallback(() => {
+    clearTimeout(destroyTimeoutRef.current)
+    destroyTimeoutRef.current = setTimeout(hideAndDestroyImmediately, duration)
+  })
+  const pauseDestroy = useNonReactiveCallback(() => {
+    clearTimeout(destroyTimeoutRef.current)
+  })
+
+  useEffect(() => {
+    hideAndDestroyAfterTimeout()
+  }, [hideAndDestroyAfterTimeout])
+
+  const panGesture = useMemo(() => {
+    return Gesture.Pan()
+      .activeOffsetY([-10, 10])
+      .failOffsetX([-10, 10])
+      .maxPointers(1)
+      .onStart(() => {
+        'worklet'
+        if (!alive) return
+        isPanning.set(true)
+        runOnJS(pauseDestroy)()
+      })
+      .onUpdate(e => {
+        'worklet'
+        if (!alive) return
+        dismissSwipeTranslateY.value = e.translationY
+      })
+      .onEnd(e => {
+        'worklet'
+        if (!alive) return
+        runOnJS(hideAndDestroyAfterTimeout)()
+        isPanning.set(false)
+        if (e.velocityY < -100) {
+          if (dismissSwipeTranslateY.value === 0) {
+            // HACK: If the initial value is 0, withDecay() animation doesn't start.
+            // This is a bug in Reanimated, but for now we'll work around it like this.
+            dismissSwipeTranslateY.value = 1
+          }
+          dismissSwipeTranslateY.value = withDecay({
+            velocity: e.velocityY,
+            velocityFactor: Math.max(3500 / Math.abs(e.velocityY), 1),
+            deceleration: 1,
+          })
+        } else {
+          dismissSwipeTranslateY.value = withSpring(0, {
+            stiffness: 500,
+            damping: 50,
+          })
+        }
+      })
+  }, [
+    dismissSwipeTranslateY,
+    isPanning,
+    alive,
+    hideAndDestroyAfterTimeout,
+    pauseDestroy,
+  ])
+
+  const topOffset = top + 10
+
+  useAnimatedReaction(
+    () =>
+      !isPanning.get() &&
+      dismissSwipeTranslateY.get() < -topOffset - cardHeight,
+    (isSwipedAway, prevIsSwipedAway) => {
+      'worklet'
+      if (isSwipedAway && !prevIsSwipedAway) {
+        runOnJS(destroy)()
+      }
+    },
+  )
+
+  const animatedStyle = useAnimatedStyle(() => {
+    const translation = dismissSwipeTranslateY.get()
+    return {
+      transform: [
+        {
+          translateY: translation > 0 ? translation ** 0.7 : translation,
+        },
+      ],
+    }
+  })
+
+  return (
+    <GestureHandlerRootView
+      style={[a.absolute, {top: topOffset, left: 16, right: 16}]}
+      pointerEvents="box-none">
+      {alive && (
+        <Animated.View
+          entering={SlideInUp.easing(Easing.out(Easing.exp)).duration(
+            TOAST_ANIMATION_DURATION,
+          )}
+          exiting={SlideOutUp.easing(Easing.in(Easing.exp)).duration(
+            TOAST_ANIMATION_DURATION * 0.7,
+          )}
+          onLayout={evt => setCardHeight(evt.nativeEvent.layout.height)}
+          accessibilityRole="alert"
+          accessible={true}
+          accessibilityLabel={a11yLabel}
+          accessibilityHint=""
+          onAccessibilityEscape={hideAndDestroyImmediately}
+          style={[a.flex_1, animatedStyle]}>
+          <GestureDetector gesture={panGesture}>
+            <Toast content={content} type={type} />
+          </GestureDetector>
+        </Animated.View>
+      )}
+    </GestureHandlerRootView>
+  )
+}
diff --git a/src/components/Toast/index.web.tsx b/src/components/Toast/index.web.tsx
new file mode 100644
index 000000000..f6ceda568
--- /dev/null
+++ b/src/components/Toast/index.web.tsx
@@ -0,0 +1,107 @@
+/*
+ * Note: relies on styles in #/styles.css
+ */
+
+import {useEffect, useState} from 'react'
+import {AccessibilityInfo, Pressable, View} from 'react-native'
+import {msg} from '@lingui/macro'
+import {useLingui} from '@lingui/react'
+
+import {atoms as a, useBreakpoints} from '#/alf'
+import {DEFAULT_TOAST_DURATION} from '#/components/Toast/const'
+import {Toast} from '#/components/Toast/Toast'
+import {type ToastApi, type ToastType} from '#/components/Toast/types'
+
+const TOAST_ANIMATION_STYLES = {
+  entering: {
+    animation: 'toastFadeIn 0.3s ease-out forwards',
+  },
+  exiting: {
+    animation: 'toastFadeOut 0.2s ease-in forwards',
+  },
+}
+
+interface ActiveToast {
+  type: ToastType
+  content: React.ReactNode
+  a11yLabel: string
+}
+type GlobalSetActiveToast = (_activeToast: ActiveToast | undefined) => void
+let globalSetActiveToast: GlobalSetActiveToast | undefined
+let toastTimeout: NodeJS.Timeout | undefined
+type ToastContainerProps = {}
+
+export const ToastContainer: React.FC<ToastContainerProps> = ({}) => {
+  const {_} = useLingui()
+  const {gtPhone} = useBreakpoints()
+  const [activeToast, setActiveToast] = useState<ActiveToast | undefined>()
+  const [isExiting, setIsExiting] = useState(false)
+
+  useEffect(() => {
+    globalSetActiveToast = (t: ActiveToast | undefined) => {
+      if (!t && activeToast) {
+        setIsExiting(true)
+        setTimeout(() => {
+          setActiveToast(t)
+          setIsExiting(false)
+        }, 200)
+      } else {
+        if (t) {
+          AccessibilityInfo.announceForAccessibility(t.a11yLabel)
+        }
+        setActiveToast(t)
+        setIsExiting(false)
+      }
+    }
+  }, [activeToast])
+
+  return (
+    <>
+      {activeToast && (
+        <View
+          style={[
+            a.fixed,
+            {
+              left: a.px_xl.paddingLeft,
+              right: a.px_xl.paddingLeft,
+              bottom: a.px_xl.paddingLeft,
+              ...(isExiting
+                ? TOAST_ANIMATION_STYLES.exiting
+                : TOAST_ANIMATION_STYLES.entering),
+            },
+            gtPhone && [
+              {
+                maxWidth: 380,
+              },
+            ],
+          ]}>
+          <Toast content={activeToast.content} type={activeToast.type} />
+          <Pressable
+            style={[a.absolute, a.inset_0]}
+            accessibilityLabel={_(msg`Dismiss toast`)}
+            accessibilityHint=""
+            onPress={() => setActiveToast(undefined)}
+          />
+        </View>
+      )}
+    </>
+  )
+}
+
+export const toast: ToastApi = {
+  show(props) {
+    if (toastTimeout) {
+      clearTimeout(toastTimeout)
+    }
+
+    globalSetActiveToast?.({
+      type: props.type,
+      content: props.content,
+      a11yLabel: props.a11yLabel,
+    })
+
+    toastTimeout = setTimeout(() => {
+      globalSetActiveToast?.(undefined)
+    }, props.duration || DEFAULT_TOAST_DURATION)
+  },
+}
diff --git a/src/components/Toast/types.ts b/src/components/Toast/types.ts
new file mode 100644
index 000000000..9f1245fa2
--- /dev/null
+++ b/src/components/Toast/types.ts
@@ -0,0 +1,24 @@
+export type ToastType = 'default' | 'success' | 'error' | 'warning' | 'info'
+
+export type ToastApi = {
+  show: (props: {
+    /**
+     * The type of toast to show. This determines the styling and icon used.
+     */
+    type: ToastType
+    /**
+     * A string, `Text`, or `Span` components to render inside the toast. This
+     * allows additional formatting of the content, but should not be used for
+     * interactive elements link links or buttons.
+     */
+    content: React.ReactNode | string
+    /**
+     * Accessibility label for the toast, used for screen readers.
+     */
+    a11yLabel: string
+    /**
+     * Defaults to `DEFAULT_TOAST_DURATION` from `#components/Toast/const`.
+     */
+    duration?: number
+  }) => void
+}