// detachable_elements.ysl2

//

// compute what elements are required by pages

// and decide where to cut when removing/attaching

// pages elements on page switch

// returns all directly or indirectly refered elements

def "func:refered_elements" {

param "elems";

const "descend", "$elems/descendant-or-self::svg:*";

const "clones", "$descend[self::svg:use]";

const "originals", "//svg:*[concat('#',@id) = $clones/@xlink:href]";

choose {

when "$originals"

result "$descend | func:refered_elements($originals)";

otherwise

result "$descend";

}

}

def "func:all_related_elements" {

param "page";

const "page_overlapping_geometry", "func:overlapping_geometry($page)";

const "page_overlapping_elements", "//svg:*[@id = $page_overlapping_geometry/@Id]";

const "page_sub_elements", "func:refered_elements($page | $page_overlapping_elements)";

result "$page_sub_elements";

}

def "func:required_elements" {

param "pages";

choose{

when "$pages"{

result """func:all_related_elements($pages[1])

| func:required_elements($pages[position()!=1])""";

}otherwise{

result "/..";

}

}

}

const "required_elements",

"""//svg:defs/descendant-or-self::svg:*

| func:required_elements($hmi_pages)/ancestor-or-self::svg:*""";

const "discardable_elements", "//svg:*[not(@id = $required_elements/@id)]";

def "func:sumarized_elements" {

param "elements";

const "short_list", "$elements[not(ancestor::*/@id = $elements/@id)]";

const "filled_groups", """$short_list/parent::svg:*[

not(descendant::*[

not(self::svg:g) and

not(@id = $discardable_elements/@id) and

not(@id = $short_list/descendant-or-self::*[not(self::svg:g)]/@id)

])]""";

const "groups_to_add", "$filled_groups[not(ancestor::*/@id = $filled_groups/@id)]";

result "$groups_to_add | $short_list[not(ancestor::svg:g/@id = $filled_groups/@id)]";

}

def "func:detachable_elements" {

param "pages";

choose{

when "$pages"{

result """func:sumarized_elements(func:all_related_elements($pages[1]))

| func:detachable_elements($pages[position()!=1])""";

}otherwise{

result "/..";

}

}

}

// Avoid nested detachables

const "_detachable_elements", "func:detachable_elements($hmi_pages)";

const "detachable_elements", "$_detachable_elements[not(ancestor::*/@id = $_detachable_elements/@id)]";