/* * site.js * * General purpose functions for manipulation of page content. * * * $Id$ * * Written by Keith Marshall * Copyright (C) 2020, 2021, MinGW.OSDN Project * * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice, this permission notice, and the following * disclaimer shall be included in all copies or substantial portions of * the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OF OR OTHER * DEALINGS IN THE SOFTWARE. * */ function set_content( item, value ) { /* Replace the existing content, if any, of the HTML element with * id attribute named "item", (if such an element exists), with new * content as specified by "value". */ var element = document.getElementById( item ); if( element ) element.innerHTML = value; return element; } function set_page( title, text ) { /* Helper function, for use in overlay page scripts, to update * the "title" and "subtitle" fields within the page header; note * that "text" may, and should, use ASCII hyphen-minus where any * hyphen is to be represented; these will be replaced by HTML * non-breaking hyphen entities, on header field assignment. */ if( title == "title" ) document.title = text; set_content( "page-".concat( title ), text.replace( /-/g, "‑" )); } function load_content( container, src ) { /* Set the content of the specified HTML "container" element, by * injection of the entire contents of an external file which is * fetched by http server request; (either an http, or an https, * server connection is required; does not work for local files). */ var request_handler = new XMLHttpRequest(); request_handler.onreadystatechange = function() { if( this.readyState == this.DONE ) switch( this.status ) { case 200: var element = set_content( container, this.responseText ); var idx; element = element.getElementsByTagName( "script" ); set_content( "e404-missing-page", document.URL ); for( idx = 0; idx < element.length; idx++ ) { var onload_action = Function( element[idx].innerHTML ); onload_action(); } if( src.includes("#") ) { src = src.substring( src.indexOf("#") + 1, src.length ); element = document.getElementById( src ); if( element ) element.scrollIntoView(); } break; case 404: load_content( container, "missing.html" ); } } request_handler.open( "GET", src, true ); request_handler.send(); } function load_page( src ) { /* Load page content from the HTML fragment file, as determined * from the specified "src" URL; if no alternative fragment name * is specified, fall back to loading "about.html". */ const ref = "?page="; const div = "page-content"; set_content( div, null ); load_content( "header", "header.html" ); if( src.includes( ref ) ) src = src.substring( src.indexOf( ref ) + ref.length, src.length ); else src = "about.html"; load_content( div, src ); } /* Web-Search Widget Helper Functions * ---------------------------------- * Derived from the DuckDuckGo.com search widget implementation by * Juri Wornowitski, as described at https://www.plainlight.com/ddg, * these facilitate incorporation of multiple search widget variants, * at multiple locations across the site. * */ function ddg_widget( ref ) { /* Acquire a reference to the "submit" button, within the search * widget; the containing "form" element uses this to simulate a * click event, if the form is submitted by pressing the "enter" * key, when the "input" field has the focus. */ ref = ref.getElementsByTagName( "button" ); for( idx = 0; idx < ref.length; idx++ ) if( ref[idx].type == "submit" ) return ref[idx]; return undefined; } function ddg_google_search_site( domain ) { /* Encode a search "domain" as a "site:" reference, to be appended * to the query URL, when a DuckDuckGo.com search is directed to the * Google search engine, via DuckDuckGo.com's "bang" facility. */ return "+".concat( encodeURIComponent( "site:".concat( domain ))); } function ddg_bang( src, query, domain ) { /* Set up a query, using DuckDuckGo.com's "bang" facility, (directed * to the "bang" identified by "src"); append the query, appropriately * encoded, and optionally a "domain" URL whence the query results are * to be retrieved. */ const bang = "https://duckduckgo.com?q=".concat( encodeURIComponent( "!" )); query = bang.concat( src.concat( "+".concat( encodeURIComponent( query )))); return query.concat( domain ); } function ddg_query( widget ) { /* Retrieve the current value entered into the query "input" field; * (this is identified by having a "name" property value of "q"). */ widget = widget.getElementsByTagName( "input" ); for( idx = 0; idx < widget.length; idx++ ) if( widget[idx].name == "q" ) return widget[idx].value; return undefined; } function ddg_google_search( widget, target, domain ) { /* Initiate a Google search, from the DuckDuckGo.com search widget; * (the "widget" reference is initially associated with the "submit" * button, whence we retrieve the query context via the parent form). * If "domain" is not null, it is assumed to represent a "site:" URL, * where the search is to be performed, while boolean value "target" * indicates whether or not a new browser window is to be opened to * display the search results. */ var query = ddg_query( widget.parentElement ); if( domain.length > 0 ) domain = ddg_google_search_site( domain ); if( target ) window.open( ddg_bang( "g", query, domain )); else ddg_bang( "g", query, domain ); return false; } function osdn_archive( project, list ) { /* Construct a URL to represent the search domain for an OSDN.net * mailing list archive, for any specified "list", belonging to a * specified "project". */ const template = "https://osdn.net/projects/%P%/lists/archive/"; return template.replace( "%P%", project ).concat( list ); } /* $RCSfile$: end of file */