From e9429ac5571547541c9c7030ebb5cd3b12f5ce2a Mon Sep 17 00:00:00 2001
From: Alexis <35.alexis.pele@gmail.com>
Date: Fri, 3 May 2024 23:47:10 +0200
Subject: [PATCH] First draft of function that handles seeing previous / next
 events

---
 src/components/calendar/CalendarEvent.vue     |  6 +-
 .../calendar/CalendarEventDetails.vue         | 52 +++++++++-
 src/components/calendar/CalendarMenuNav.vue   |  2 +-
 src/stores/EventStore.ts                      | 96 ++++++++++++++++++-
 4 files changed, 147 insertions(+), 9 deletions(-)

diff --git a/src/components/calendar/CalendarEvent.vue b/src/components/calendar/CalendarEvent.vue
index 9f303c9..7f1c6e5 100644
--- a/src/components/calendar/CalendarEvent.vue
+++ b/src/components/calendar/CalendarEvent.vue
@@ -1,11 +1,11 @@
 <script lang="ts" setup>
+import { ref } from 'vue'
 import { cn } from '@/lib/utils'
+import { areDatesIdentical, type LeimDate } from '@/models/Date'
+
 import { Popover, PopoverTrigger } from '@/components/ui/popover'
 import type { CalendarEvent } from '@/models/Events'
-
 import CalendarEventDetails from './CalendarEventDetails.vue'
-import { areDatesIdentical, type LeimDate } from '@/models/Date'
-import { ref } from 'vue'
 
 const props = defineProps<{
   event: CalendarEvent
diff --git a/src/components/calendar/CalendarEventDetails.vue b/src/components/calendar/CalendarEventDetails.vue
index 7175349..49b2b8f 100644
--- a/src/components/calendar/CalendarEventDetails.vue
+++ b/src/components/calendar/CalendarEventDetails.vue
@@ -2,12 +2,21 @@
 import { getRelativeString, type LeimDate } from '@/models/Date'
 import type { CalendarEvent } from '@/models/Events'
 import { useCalendar } from '@/stores/CalendarStore'
+import { useCalendarEvents } from '@/stores/EventStore'
 
-import { PhHourglassMedium, PhAlarm, PhHourglassHigh, PhHourglassLow } from '@phosphor-icons/vue'
+import {
+  PhHourglassMedium,
+  PhAlarm,
+  PhHourglassHigh,
+  PhHourglassLow,
+  PhArrowBendDoubleUpLeft,
+  PhArrowBendDoubleUpRight
+} from '@phosphor-icons/vue'
 import { Badge } from '@/components/ui/badge'
 import { PopoverContent } from '@/components/ui/popover'
 
 const { defaultDate, getFormattedDateTitle, jumpToDate } = useCalendar()
+const { getRelativeEvent } = useCalendarEvents()
 
 const props = defineProps<{
   event: CalendarEvent
@@ -16,7 +25,9 @@ const props = defineProps<{
   isEndEvent?: boolean
 }>()
 
-const emit = defineEmits(['query:close-popover'])
+const emit = defineEmits<{
+  (e: 'query:close-popover'): void
+}>()
 
 const dateDifference: string = getRelativeString(defaultDate, props.event.startDate)
 const dateDuration: string | null = props.event.endDate
@@ -27,6 +38,16 @@ function handleJumpToDate(date: LeimDate) {
   jumpToDate(date)
   emit('query:close-popover')
 }
+
+function handleGotoRelativeEvent(position: 'next' | 'prev' = 'next') {
+  try {
+    const { targetDate } = getRelativeEvent(props.event, position, props.isEndEvent)
+
+    handleJumpToDate(targetDate)
+  } catch (err) {
+    console.log(err)
+  }
+}
 </script>
 
 <template>
@@ -123,11 +144,36 @@ function handleJumpToDate(date: LeimDate) {
         </button>
       </Badge>
       <Badge class="hover:opacity-100 hover:bg-slate-300" as-child title="Naviguer à la fin">
-        <button class="flex gap-1" @click="handleJumpToDate(event.endDate!)">
+        <button
+          class="flex gap-1"
+          @click="handleJumpToDate(event.endDate!)"
+          title="Naviguer à la fin"
+        >
           <PhHourglassLow size="16" weight="fill" /> Fin
         </button>
       </Badge>
     </nav>
+
+    <nav class="mt-2 flex gap-2">
+      <Badge class="hover:opacity-100 hover:bg-slate-300" as-child>
+        <button
+          class="flex gap-1"
+          @click="handleGotoRelativeEvent('prev')"
+          title="Évènement précédent"
+        >
+          <PhArrowBendDoubleUpLeft size="16" weight="fill" /> Précédent
+        </button>
+      </Badge>
+      <Badge class="hover:opacity-100 hover:bg-slate-300" as-child title="Naviguer à la fin">
+        <button
+          class="flex gap-1"
+          @click="handleGotoRelativeEvent('next')"
+          title="Évènement suivant"
+        >
+          <PhArrowBendDoubleUpRight size="16" weight="fill" /> Suivant
+        </button>
+      </Badge>
+    </nav>
   </PopoverContent>
 </template>
 
diff --git a/src/components/calendar/CalendarMenuNav.vue b/src/components/calendar/CalendarMenuNav.vue
index 05d303e..d68c0eb 100644
--- a/src/components/calendar/CalendarMenuNav.vue
+++ b/src/components/calendar/CalendarMenuNav.vue
@@ -1,4 +1,5 @@
 <script lang="ts" setup>
+import { computed, type ComputedRef } from 'vue'
 import { useCalendar } from '@/stores/CalendarStore'
 
 import { Tooltip, TooltipContent, TooltipProvider, TooltipTrigger } from '@/components/ui/tooltip'
@@ -9,7 +10,6 @@ import {
   PhCaretRight
 } from '@phosphor-icons/vue'
 import Button from '../ui/button/Button.vue'
-import { computed, type ComputedRef } from 'vue'
 
 interface DirectionLabels {
   pastFar: string
diff --git a/src/stores/EventStore.ts b/src/stores/EventStore.ts
index 964f208..4753c1e 100644
--- a/src/stores/EventStore.ts
+++ b/src/stores/EventStore.ts
@@ -1,5 +1,5 @@
 import { initialEvents } from '@/data/Events'
-import { compareDates, convertDateToDays, daysPerMonth } from '@/models/Date'
+import { compareDates, convertDateToDays, daysPerMonth, type LeimDate } from '@/models/Date'
 import type { CalendarEvent } from '@/models/Events'
 import { defineStore } from 'pinia'
 import { ref, watch, type Ref } from 'vue'
@@ -108,5 +108,97 @@ export const useCalendarEvents = defineStore('calendar-events', () => {
     return allEvents.filter((event) => shouldEventBeDisplayed(event))
   }
 
-  return { allEvents, currentEvents }
+  /**
+   * From a base event, gets the next or previous in the timeline
+   * @todo **This should probably be extracted to function FIRST with dates only, as the initialIsEnd param is only used at the beggining to establish a pivot**
+   *
+   * @param event The event at a given position in the data
+   * @param position Whether we should get the next or previous event
+   * @returns The next event in chronological order
+   */
+  function getRelativeEvent(
+    event: CalendarEvent,
+    position: 'next' | 'prev' = 'next',
+    initialIsEnd: boolean = false
+  ): { event: CalendarEvent; targetDate: LeimDate } {
+    let eventPivotValue: number // Day value of the date that the user interacted with
+
+    if (initialIsEnd && event.endDate) {
+      eventPivotValue = convertDateToDays(event.endDate)
+    } else {
+      eventPivotValue = convertDateToDays(event.startDate)
+    }
+
+    const t: { eventData: CalendarEvent; distance: number; targetKey: 'startDate' | 'endDate' }[] =
+      []
+    let eventPivotIndex: number | null = null // Pivot index to save
+    let realPositon: number = 0
+
+    // Loop over all event once to convert the structure to a usable one
+    for (let i = 0; i < allEvents.length; i++) {
+      const e: CalendarEvent = allEvents[i]
+      // Estimate distance from pivot
+      const startDateDays: number = convertDateToDays(e.startDate)
+      const startDistance: number = startDateDays - eventPivotValue
+
+      // Push startDate to comparator array
+      t.push({
+        eventData: e,
+        distance: startDistance,
+        targetKey: 'startDate'
+      })
+
+      // If the distance from initial pivot is 0, this is our target index
+      if (startDistance === 0) {
+        eventPivotIndex = realPositon
+      }
+
+      // Check the same things for endDate
+      if (e.endDate) {
+        realPositon++
+        const endDateDays: number = convertDateToDays(e.endDate)
+        const endDistance: number = endDateDays - eventPivotValue
+
+        // Push optional endDate to comparator array
+        t.push({
+          eventData: e,
+          distance: endDistance,
+          targetKey: 'endDate'
+        })
+
+        // Same as above, but with the optional end distance
+        if (endDistance === 0) {
+          eventPivotIndex = realPositon
+        }
+      }
+
+      realPositon++
+
+      // Optimization possible with index skipping (once we find the pivot index)
+    }
+
+    // If SOMEHOW we can't find the pivot index
+    if (eventPivotIndex === null) {
+      throw new Error("Impossible de trouver l'évènement initial.")
+    }
+
+    let returnEventIndex: number | null = null // Output event index
+    if (position === 'next') {
+      returnEventIndex = eventPivotIndex + 1
+    } else {
+      returnEventIndex = eventPivotIndex - 1
+    }
+
+    if (!t[returnEventIndex])
+      throw new Error(
+        "Aucun évènement trouvé ; Peut-être l'évènement se situe au début ou à la fin du calendrier ?"
+      )
+
+    return {
+      event: t[returnEventIndex].eventData,
+      targetDate: t[returnEventIndex].eventData[t[returnEventIndex].targetKey]!
+    }
+  }
+
+  return { allEvents, currentEvents, getRelativeEvent }
 })