// Syntax notes:
//     Blah!Int is generic type application, equivalent to C++'s Blah<Int>
//     Ptr!Type is a pointer to a Type object
//     Type? is Option!Type, e.g. either a Type object, or None
// Semantics notes:
//     struct is a C-style struct
//     union is a typed union, e.g. union!(A, B) can be either A, or B, but not at the same time
// Type notes:
//     Splashmap is a map with multiple key and value types, where keys map to only some of the types
//     For example, in Splashmap!((A, A), (A, B), (B, B)):
//         A can map to either A or B, in other words union!(A, B)
//         B can map only to B
//     None is both null and nullptr.

Browser = {
    // Workspaces are groups of tabs and groups, displayed on the side of the screen, as vertical tabs,
    //  with each workspace's tabs and groups shown as horizontal tabs
    workspaces: OrderedSet!Workspace

    // The browser's view - rendered page, address bar, etc.
    view: BrowserView
}

Workspace = GroupView

GroupView = struct {
    actual_group: Ptr!Group

    view_options: GroupViewOptions
}

GroupViewOptions = struct {
    // Is this group view compacted, to occupy as much space as a single tab?
    compacted: Bool
}

TabOrGroup = union {
    tab: Tab;
    group: Group
}

Group = struct {
    // The set of tabs and subgroup in this group, ordered
    content: OrderedSet!TabOrGroup

    // Views(with individual view options) for tabs and groups
    views: Splashmap!(
        (Tab, TabView),
        (Group, GroupView)
    )
}

TabView = struct {
    actual_tab: Ptr!Tab

    view_options: TabViewOptions
}

Tab = struct {
    // Actual page content, None if tab is not currently loaded
    actual_content: PageContent?

    // Tags, primarily for bookmarking, but could be used to, e.g.
    //  display all "homework"-tagged tabs in a group
    tags: Set!Tag

    options: TabOptions
}

TabOptions = struct {
    // If closed, only unload it from memory, reopen on click
    persistent: Bool

    // Only show an icon, no title, for compacting
    minimized: Bool

    // Is it currently loaded into memory?
    loaded: Bool

    // If closed, it will still be stored as a bookmark
    bookmarked: Bool

    // Is it open in any view right now? Only applicable to bookmarked tabs as they are not moved into history when closed
    open: Bool
}