Refactor event context menu into its separate file

Have only one menu component attached to the EventList,
instead of every delegate carrying its own.

src/gui/Pages/Chat/Timeline/EventContextMenu.qml

@@ -0,0 +1,175 @@
+// SPDX-License-Identifier: LGPL-3.0-or-later
+
+import QtQuick 2.12
+import QtQuick.Layouts 1.12
+import Clipboard 0.1
+import "../../.."
+import "../../../Base"
+import "../../../PythonBridge"
+
+HMenu {
+    id: menu
+
+    property HListView eventList
+    property int eventIndex: 0
+    property Item eventDelegate: null  // TODO: Qt 5.13: just use itemAtIndex()
+    property var hoveredMedia: []      // [Utils.Media.<Type>, url, title]
+    property string hoveredLink: ""
+
+    readonly property QtObject event: eventList.model.get(eventIndex)
+
+    readonly property bool isEncryptedMedia:
+        Object.keys(JSON.parse(event.media_crypt_dict)).length > 0
+
+    function spawn(eventIndex, eventDelegate, hoveredMedia=[], hoveredUrl="") {
+        menu.eventIndex    = eventIndex
+        menu.eventDelegate = eventDelegate
+        menu.hoveredMedia  = hoveredMedia
+        menu.hoveredLink   = hoveredUrl
+        menu.popup()
+    }
+
+
+    onClosed: {
+        hoveredMedia = []
+        hoveredLink  = ""
+    }
+
+    HMenuItem {
+        icon.name: "toggle-select-message"
+        text: event.id in eventList.checked ? qsTr("Deselect") : qsTr("Select")
+        onTriggered: eventList.toggleCheck(eventIndex)
+    }
+
+    HMenuItem {
+        visible: eventList.selectedCount >= 2
+        icon.name: "deselect-all-messages"
+        text: qsTr("Deselect all")
+        onTriggered: eventList.checked = {}
+    }
+
+    HMenuItem {
+        visible: eventIndex !== 0
+        icon.name: "select-until-here"
+        text: qsTr("Select until here")
+        onTriggered: eventList.checkFromLastToHere(eventIndex)
+    }
+
+    HMenuItem {
+        icon.name: "open-externally"
+        text: qsTr("Open externally")
+        visible: Boolean(event.media_url)
+        onTriggered: eventList.openMediaExternally(event)
+    }
+
+    HMenuItem {
+        icon.name: "copy-local-path"
+        text: qsTr("Copy local path")
+        visible: Boolean(event.media_local_path)
+        onTriggered:
+            Clipboard.text =
+                event.media_local_path.replace(/^file:\/\//, "")
+    }
+
+    HMenuItem {
+        id: copyMedia
+        icon.name: "copy-link"
+        text:
+            menu.hoveredMedia.length === 0 ||
+            menu.isEncryptedMedia ?
+            "" :
+
+            menu.hoveredMedia[0] === Utils.Media.File ?
+            qsTr("Copy file address") :
+
+            menu.hoveredMedia[0] === Utils.Media.Image ?
+            qsTr("Copy image address") :
+
+            menu.hoveredMedia[0] === Utils.Media.Video ?
+            qsTr("Copy video address") :
+
+            qsTr("Copy audio address")
+
+        visible: Boolean(text)
+        onTriggered: Clipboard.text = event.media_http_url  // FIXME
+    }
+
+    HMenuItem {
+        icon.name: "copy-link"
+        text: qsTr("Copy link address")
+        visible: Boolean(menu.hoveredLink)
+        onTriggered: Clipboard.text = menu.hoveredLink
+    }
+
+    HMenuItem {
+        icon.name: "copy-text"
+        text:
+            eventList.selectedCount ? qsTr("Copy selection") :
+            menu.hoveredMedia.length > 0 ? qsTr("Copy filename") :
+            qsTr("Copy text")
+
+        onTriggered: {
+            if (! eventList.selectedCount){
+                Clipboard.text = JSON.parse(event.source).body
+                return
+            }
+
+            eventList.copySelectedDelegates()
+        }
+    }
+
+    HMenuItem {
+        icon.name: "reply-to"
+        text: qsTr("Reply")
+
+        onTriggered: {
+            chat.replyToEventId     = event.id
+            chat.replyToUserId      = event.sender_id
+            chat.replyToDisplayName = event.sender_name
+        }
+    }
+
+    HMenuItemPopupSpawner {
+        readonly property var events:
+            eventList.selectedCount ?
+            eventList.redactableCheckedEvents :
+
+            eventList.canRedact(event) ?
+            [event] :
+
+            []
+
+        icon.name: "remove-message"
+        text: qsTr("Remove")
+        enabled: properties.eventSenderAndIds.length
+
+        popup: "Popups/RedactPopup.qml"
+        properties: ({
+            preferUserId: chat.userId,
+            roomId: chat.roomId,
+            eventSenderAndIds: events.map(ev => [ev.sender_id, ev.id]),
+
+            onlyOwnMessageWarning:
+                ! chat.roomInfo.can_redact_all &&
+                events.length < eventList.selectedCount
+        })
+    }
+
+    HMenuItem {
+        icon.name: "debug"
+        text: qsTr("Debug this event")
+        onTriggered: mainUI.debugConsole.toggle(eventDelegate, "t.json()")
+    }
+
+    HMenuItemPopupSpawner {
+        icon.name: "clear-messages"
+        text: qsTr("Clear messages")
+
+        popup: "Popups/ClearMessagesPopup.qml"
+        properties: ({
+            userId: chat.userId,
+            roomId: chat.roomId,
+            preClearCallback: eventList.uncheckAll,
+        })
+    }
+}