v/vlib/net/html/dom.v

190 lines
5.8 KiB
V

module html
import os
// The W3C Document Object Model (DOM) is a platform and language-neutral
// interface that allows programs and scripts to dynamically access and
// update the content, structure, and style of a document.
//
// https://www.w3.org/TR/WD-DOM/introduction.html
pub struct DocumentObjectModel {
mut:
root &Tag
constructed bool
btree BTree
all_tags []&Tag
all_attributes map[string][]&Tag
close_tags map[string]bool // add a counter to see count how many times is closed and parse correctly
attributes map[string][]string
tag_attributes map[string][][]&Tag
tag_type map[string][]&Tag
debug_file os.File
}
[if debug]
fn (mut dom DocumentObjectModel) print_debug(data string) {
$if debug {
if data.len > 0 {
dom.debug_file.writeln(data) or { panic(err) }
}
}
}
[inline]
fn is_close_tag(tag &Tag) bool {
return tag.name.len > 0 && tag.name[0] == `/`
}
fn (mut dom DocumentObjectModel) where_is(item_name string, attribute_name string) int {
if attribute_name !in dom.attributes {
dom.attributes[attribute_name] = []string{}
}
mut string_array := dom.attributes[attribute_name]
mut counter := 0
for value in string_array {
if value == item_name {
return counter
}
counter++
}
string_array << item_name
dom.attributes[attribute_name] = string_array
return string_array.len - 1
}
fn (mut dom DocumentObjectModel) add_tag_attribute(tag &Tag) {
for attribute_name, _ in tag.attributes {
attribute_value := tag.attributes[attribute_name]
location := dom.where_is(attribute_value, attribute_name)
if attribute_name !in dom.tag_attributes {
dom.tag_attributes[attribute_name] = []
}
for {
mut temp_array := dom.tag_attributes[attribute_name]
temp_array << []&Tag{}
dom.tag_attributes[attribute_name] = temp_array
if location < dom.tag_attributes[attribute_name].len + 1 {
break
}
}
mut temp_array := dom.tag_attributes[attribute_name][location]
temp_array << tag
dom.tag_attributes[attribute_name][location] = temp_array
}
}
fn (mut dom DocumentObjectModel) add_tag_by_type(tag &Tag) {
tag_name := tag.name
if !(tag_name in dom.tag_type) {
dom.tag_type[tag_name] = [tag]
} else {
mut temp_array := dom.tag_type[tag_name]
temp_array << tag
dom.tag_type[tag_name] = temp_array
}
}
fn (mut dom DocumentObjectModel) add_tag_by_attribute(tag &Tag) {
for attribute_name in tag.attributes.keys() {
if attribute_name !in dom.all_attributes {
dom.all_attributes[attribute_name] = [tag]
} else {
mut temp_array := dom.all_attributes[attribute_name]
temp_array << tag
dom.all_attributes[attribute_name] = temp_array
}
}
}
fn (mut dom DocumentObjectModel) construct(tag_list []&Tag) {
dom.constructed = true
mut temp_map := map[string]int{}
mut temp_int := null_element
mut temp_string := ''
mut stack := Stack{}
dom.btree = BTree{}
dom.root = tag_list[0]
dom.all_tags = [tag_list[0]]
temp_map['0'] = dom.btree.add_children(tag_list[0])
stack.push(0)
root_index := 0
for index := 1; index < tag_list.len; index++ {
mut tag := tag_list[index]
dom.print_debug(tag.str())
if is_close_tag(tag) {
temp_int = stack.peek()
temp_string = tag.name[1..]
for !is_null(temp_int) && temp_string != tag_list[temp_int].name
&& !tag_list[temp_int].closed {
dom.print_debug(temp_string + ' >> ' + tag_list[temp_int].name + ' ' +
(temp_string == tag_list[temp_int].name).str())
stack.pop()
temp_int = stack.peek()
}
temp_int = stack.peek()
temp_int = if !is_null(temp_int) { stack.pop() } else { root_index }
if is_null(temp_int) {
stack.push(root_index)
}
dom.print_debug('Removed ' + temp_string + ' -- ' + tag_list[temp_int].name)
} else if tag.name.len > 0 {
dom.add_tag_attribute(tag) // error here
dom.add_tag_by_attribute(tag)
dom.add_tag_by_type(tag)
dom.all_tags << tag
temp_int = stack.peek()
if !is_null(temp_int) {
dom.btree.move_pointer(temp_map[temp_int.str()])
temp_map[index.str()] = dom.btree.add_children(tag)
mut temp_tag := tag_list[temp_int]
position_in_parent := temp_tag.add_child(tag) // tag_list[temp_int] = temp_tag
tag.add_parent(temp_tag, position_in_parent)
/*
dom.print_debug("Added ${tag.name} as child of '" + tag_list[temp_int].name +
"' which now has ${dom.btree.get_children().len} childrens")
*/
dom.print_debug("Added $tag.name as child of '" + temp_tag.name +
"' which now has $temp_tag.children.len childrens")
} else { // dom.new_root(tag)
stack.push(root_index)
}
temp_string = '/' + tag.name
if temp_string in dom.close_tags && !tag.closed { // if tag ends with />
dom.print_debug('Pushed ' + temp_string)
stack.push(index)
}
}
} // println(tag_list[root_index]) for debug purposes
dom.root = tag_list[0]
}
// get_tag_by_attribute_value retrieves all the tags in the document that has the given attribute name and value.
pub fn (mut dom DocumentObjectModel) get_tag_by_attribute_value(name string, value string) []&Tag {
location := dom.where_is(value, name)
return if dom.tag_attributes[name].len > location {
dom.tag_attributes[name][location]
} else {
[]&Tag{}
}
}
// get_tag retrieves all the tags in the document that has the given tag name.
pub fn (dom DocumentObjectModel) get_tag(name string) []&Tag {
return if name in dom.tag_type { dom.tag_type[name] } else { []&Tag{} }
}
// get_tag_by_attribute retrieves all the tags in the document that has the given attribute name.
pub fn (dom DocumentObjectModel) get_tag_by_attribute(name string) []&Tag {
return if name in dom.all_attributes { dom.all_attributes[name] } else { []&Tag{} }
}
// get_root returns the root of the document.
pub fn (dom DocumentObjectModel) get_root() &Tag {
return dom.root
}
// get_tags returns all of the tags stored in the document.
pub fn (dom DocumentObjectModel) get_tags() []&Tag {
return dom.all_tags
}