mobile/android/fenix/app/src/main/java/org/mozilla/fenix/library/historymetadata/HistoryMetadataGroupFragmentStore.kt

   1 /* This Source Code Form is subject to the terms of the Mozilla Public
   2  * License, v. 2.0. If a copy of the MPL was not distributed with this
   3  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   4
   5 package org.mozilla.fenix.library.historymetadata
   6
   7 import mozilla.components.lib.state.Action
   8 import mozilla.components.lib.state.State
   9 import mozilla.components.lib.state.Store
  10 import org.mozilla.fenix.components.AppStore
  11 import org.mozilla.fenix.library.history.History
  12 import org.mozilla.fenix.library.history.PendingDeletionHistory
  13 import org.mozilla.fenix.library.historymetadata.view.HistoryMetadataGroupView
  14
  15 /**
  16  * The [Store] for holding the [HistoryMetadataGroupFragmentState] and applying
  17  * [HistoryMetadataGroupFragmentAction]s.
  18  */
  19 class HistoryMetadataGroupFragmentStore(initialState: HistoryMetadataGroupFragmentState) :
  20     Store<HistoryMetadataGroupFragmentState, HistoryMetadataGroupFragmentAction>(
  21         initialState,
  22         ::historyStateReducer,
  23     )
  24
  25 /**
  26  * Actions to dispatch through the [HistoryMetadataGroupFragmentStore] to modify the
  27  * [HistoryMetadataGroupFragmentState] through the [historyStateReducer].
  28  */
  29 sealed class HistoryMetadataGroupFragmentAction : Action {
  30     data class UpdateHistoryItems(val items: List<History.Metadata>) :
  31         HistoryMetadataGroupFragmentAction()
  32     data class Select(val item: History.Metadata) : HistoryMetadataGroupFragmentAction()
  33     data class Deselect(val item: History.Metadata) : HistoryMetadataGroupFragmentAction()
  34
  35     /**
  36      * Updates the set of items marked for removal from the [AppStore]
  37      * to the [HistoryMetadataGroupFragmentStore], to be hidden from the UI.
  38      */
  39     data class UpdatePendingDeletionItems(val pendingDeletionItems: Set<PendingDeletionHistory>) :
  40         HistoryMetadataGroupFragmentAction()
  41     object DeselectAll : HistoryMetadataGroupFragmentAction()
  42     data class Delete(val item: History.Metadata) : HistoryMetadataGroupFragmentAction()
  43     object DeleteAll : HistoryMetadataGroupFragmentAction()
  44
  45     /**
  46      * Updates the empty state of [HistoryMetadataGroupView].
  47      */
  48     data class ChangeEmptyState(val isEmpty: Boolean) : HistoryMetadataGroupFragmentAction()
  49 }
  50
  51 /**
  52  * The state for [HistoryMetadataGroupFragment].
  53  *
  54  * @property items The list of [History.Metadata] to display.
  55  * @property pendingDeletionItems The set of [PendingDeletionHistory] marked for removal.
  56  * @property isEmpty Whether or not the screen is empty.
  57  */
  58 data class HistoryMetadataGroupFragmentState(
  59     val items: List<History.Metadata>,
  60     val pendingDeletionItems: Set<PendingDeletionHistory>,
  61     val isEmpty: Boolean,
  62 ) : State
  63
  64 /**
  65  * Reduces the history metadata state from the current state with the provided [action] to be
  66  * performed.
  67  *
  68  * @param state The current history metadata state.
  69  * @param action The action to be performed on the state.
  70  * @return the new [HistoryMetadataGroupFragmentState] with the [action] executed.
  71  */
  72 private fun historyStateReducer(
  73     state: HistoryMetadataGroupFragmentState,
  74     action: HistoryMetadataGroupFragmentAction,
  75 ): HistoryMetadataGroupFragmentState {
  76     return when (action) {
  77         is HistoryMetadataGroupFragmentAction.UpdateHistoryItems ->
  78             state.copy(items = action.items)
  79         is HistoryMetadataGroupFragmentAction.Select ->
  80             state.copy(
  81                 items = state.items.toMutableList()
  82                     .map {
  83                         if (it == action.item) {
  84                             it.copy(selected = true)
  85                         } else {
  86                             it
  87                         }
  88                     },
  89             )
  90         is HistoryMetadataGroupFragmentAction.Deselect ->
  91             state.copy(
  92                 items = state.items.toMutableList()
  93                     .map {
  94                         if (it == action.item) {
  95                             it.copy(selected = false)
  96                         } else {
  97                             it
  98                         }
  99                     },
 100             )
 101         is HistoryMetadataGroupFragmentAction.DeselectAll ->
 102             state.copy(
 103                 items = state.items.toMutableList()
 104                     .map { it.copy(selected = false) },
 105             )
 106         is HistoryMetadataGroupFragmentAction.Delete -> {
 107             val items = state.items.toMutableList()
 108             items.remove(action.item)
 109             state.copy(items = items)
 110         }
 111         is HistoryMetadataGroupFragmentAction.DeleteAll ->
 112             state.copy(items = emptyList())
 113         is HistoryMetadataGroupFragmentAction.UpdatePendingDeletionItems ->
 114             state.copy(pendingDeletionItems = action.pendingDeletionItems)
 115         is HistoryMetadataGroupFragmentAction.ChangeEmptyState -> state.copy(
 116             isEmpty = action.isEmpty,
 117         )
 118     }
 119 }