Modul:TemplUtl

 local TemplUtl = { suite = "TemplUtl",
 serial = "2022年05月16日",
 item = 52364930 };
 --[=[
 Utilities to support template programming.
 ]=]
 local Failsafe = TemplUtl;



 local fallible = function ( adjust, ahead )
 -- Check for leading character disturbing syntax
 -- Precondition:
 -- adjust -- string; trimmed wikitext
 -- ahead -- true, if leading syntax shall start on new line
 -- Postcondition:
 -- Returns string, modified if necessary
 local r = adjust;
 local c = r:byte( 1, 1 );
 local lead;
 if c <= 59 and
 ( c==35 or c==42 or c==58 or c==59 ) then
 lead = true;
 elseif c == 123 or c == 124 then
 local c2 = r:byte( 2, 1 );
 if c == 123 and c2 == 124 then
 lead = true;
 elseif ahead and c == 124 and
 ( c2 == 43 or c2 == 45 or c2 == 125 ) then
 lead = true;
 end
 end
 if lead then
 if ahead then
 r = "\n" .. r;
 else
 r = mw.text.nowiki( r:sub( 1, 1 ) ) .. r:sub( 2 );
 end
 end
 return r;
 end -- fallible()



 local fiatTitleRegExp = function ( accept )
 -- Create pattern to detect page name
 -- Precondition:
 -- accept -- string; trimmed title
 -- Postcondition:
 -- Returns string with pattern
 local start = mw.ustring.sub( accept, 1, 1 );
 local r;
 if mw.ustring.match( start, "%a" ) then
 r = string.format( "[%s%s]%s",
 mw.ustring.lower( start ),
 mw.ustring.upper( start ),
 mw.ustring.sub( accept, 2 ) );
 else
 r = accept;
 end
 if r:match( " " ) then
 r = r:gsub( "%", "%%" )
 :gsub( "[%-^.?+*()$]", "%1ドル" )
 :gsub( "_", " " )
 :gsub( "%s+", "[%s_]+" );
 end
 return r;
 end -- fiatTitleRegExp()



 local framing = function ( frame )
 -- Ensure availability of frame object
 -- Precondition:
 -- frame -- object; #invoke environment, or false
 -- Postcondition:
 -- Return frame object
 if not TemplUtl.frame then
 if type( frame ) == "table" then
 TemplUtl.frame = frame;
 else
 TemplUtl.frame = mw.getCurrentFrame();
 end
 end
 return TemplUtl.frame;
 end -- framing()



 TemplUtl.facets = function ( ask, adjust )
 local r = ask;
 if adjust == "%" and r:find( "%%%x%x" ) then
 r = mw.uri.decode( r, "PATH" );
 elseif r:find( "&", 1, true ) then
 r = mw.text.decode( r );
 end
 r = mw.ustring.gsub( r, "[%s%p%c]+", " " );
 r = mw.text.trim( r );
 return r;
 end -- TemplUtl.facets()



 TemplUtl.faculty = function ( analyze, another )
 -- Test template arg for boolean
 -- analyze -- string, boolean, number or nil
 -- another -- fallback: string, boolean, or nil
 -- "-" to test for explicit vocabulary choice
 -- Returns boolean, or "-"
 local s = type( analyze );
 local r;
 if s == "string" then
 r = mw.text.trim( analyze );
 if r == "" then
 r = TemplUtl.faculty( another, nil );
 elseif r:find( "1", 1, true ) and
 r:match( "^[0%-]*1[01%-]*$" ) then
 r = true;
 elseif r:match( "^[0%-]+$" ) then
 r = false;
 else
 r = r:lower();
 if r == "y" or
 r == "yes" or
 r == "true" or
 r == "on" then
 r = true;
 elseif r == "n" or
 r == "no" or
 r == "false" or
 r == "off" then
 r = false;
 else
 if not TemplUtl.boolang then
 -- TODO: page language
 local l, d = pcall( mw.ext.data.get, "i18n/01.tab" );
 if type( d ) == "table" and
 type( d.data ) == "table" then
 local f = function ( at )
 local e = d.data[ at ];
 l = e[ 1 ];
 s = e[ 2 ];
 if type( l ) == "boolean" and
 type( s ) == "string" then
 s = mw.text.split( s, "|" );
 for i = 1, #s do
 TemplUtl.boolang[ s[ i ] ] = l;
 end -- for i
 end
 end
 TemplUtl.boolang = { };
 f( 1 );
 f( 2 );
 else
 TemplUtl.boolang = true;
 end
 end
 if type( TemplUtl.boolang ) == "table" then
 s = TemplUtl.boolang[ r ];
 if type( s ) == "boolean" then
 r = s;
 end
 end
 if type( r ) ~= "boolean" then
 s = type( another );
 if s == "nil" then
 r = true;
 elseif s == "boolean" then
 r = another;
 elseif s == "string" then
 s = mw.text.trim( another );
 if s == "-" then
 r = "-";
 elseif s == "" then
 r = true;
 else
 r = TemplUtl.faculty( s );
 end
 end
 end
 end
 end
 elseif s == "boolean" then
 r = analyze;
 elseif s == "number" then
 r = ( analyze ~= 0 );
 else
 r = false;
 end
 return r;
 end -- TemplUtl.faculty()



 TemplUtl.failure = function ( alert, always, addClass, frame )
 -- Format error message, mostly hidden
 -- alert -- string: message
 -- always -- boolean, or nil: do not hide
 -- addClass -- string, or nil: add classes to element
 -- frame -- object, or nil
 -- Returns string
 local err = mw.html.create( "span" )
 :addClass( "error" )
 :wikitext( alert );
 local live = ( framing( frame ):preprocess( "{{REVISIONID}}" )
 == "" );
 if type( addClass ) == "string" then
 err:addClass( addClass )
 end
 if live then
 local max = 1000000000;
 local id = math.floor( os.clock() * max );
 local sign = string.format( "error_%d", id );
 local btn = mw.html.create( "span" );
 local top = mw.html.create( "div" );
 err:attr( "id", sign );
 -- TODO: LTR
 btn:css( { ["background"] = "#FFFF00",
 ["border"] = "#FF0000 3px solid",
 ["font-weight"] = "bold",
 ["padding"] = "2px",
 ["text-decoration"] = "none" } )
 :wikitext( "&gt;&gt;&gt;" );
 sign = string.format( "[[#%s|%s]]", sign, tostring( btn ) );
 top:wikitext( sign, "&#160;", alert );
 mw.addWarning( tostring( top:attr( "role", "alert" ) ) );
 elseif not always then
 err:css( { ["display"] = "none" } );
 -- err:css( { ["display"] = "inline-block",
 -- ["line-height"] = "0",
 -- ["max-height"] = "0",
 -- ["max-width"] = "0",
 -- ["visibility"] = "hidden" } );
 end
 return tostring( err );
 end -- TemplUtl.failure()



 TemplUtl.fake = function ( access )
 -- Simulation of template transclusion
 -- Precondition:
 -- access -- string; page name (template)
 if type( access ) == "string" then
 local s = mw.text.trim( access );
 if s ~= "" then
 local t = mw.title.new( s, 10 );
 if not mw.title.equals( mw.title.getCurrentTitle(), t ) and
 t.exists then
 t:getContent();
 end
 end
 end
 end -- TemplUtl.fake()



 TemplUtl.fakes = function ( array, frame, ahead, answer )
 -- Simulation of template transclusions
 -- Precondition:
 -- array -- table, with template title strings
 -- frame -- object, or nil
 -- ahead -- string, or nil, with common prefix
 -- answer -- true, or nil, for list creation
 -- Postcondition:
 -- Returns string, if answer requested
 local e = framing( frame );
 local f = function ( a )
 e:expandTemplate{ title = a };
 end
 local s = ahead or "";
 local r;
 for k, v in pairs( array ) do
 if type( k ) == "number" and
 type( v ) == "string" then
 v = s .. mw.text.trim( v );
 pcall( f, v );
 if answer then
 if r then
 r = r .. "\n";
 else
 r = "";
 end
 r = string.format( "%s* [[Template:%s|%s]]", r, v, v );
 end
 end
 end -- for k, v
 return r;
 end -- TemplUtl.fakes()



 TemplUtl.feasible = function ( address )
 -- Does this describe an URL beginning?
 -- Precondition:
 -- address -- string; what to inspect, URL presumed
 -- Postcondition:
 -- Returns true, if URL beginning
 local start, r = address:match( "^%s*((%a*:?)//)" );
 if start then
 if r == "" then
 r = true;
 elseif r:sub( -1, -1 ) == ":" then
 local schemes = ":ftp:ftps:http:https:";
 r = ":" .. r:lower();
 if schemes:find( r, 1, true ) then
 r = true;
 else
 r = false;
 end
 else
 r = false;
 end
 end
 return r;
 end -- TemplUtl.feasible()



 TemplUtl.feed = function ( area, ahead, at, after )
 -- Detect next free "|" or "}}"
 -- Precondition:
 -- area -- string; template transclusion
 -- ahead -- string; opening element, or false
 -- at -- number; byte position in area where to start
 -- after -- true, if only to search for "}}"
 -- Postcondition:
 -- Returns
 -- -- number; byte position in area
 -- -- before "|" or "}}", may be at end
 -- -- to continue search; ahead has been closed
 -- -- true, if to be continued at number
 local j = at;
 local loop = true;
 local c, k, r, s, seek;
 if after then
 seek = "[{}<]";
 else
 seek = "[%[%]|{}<:]";
 end
 while loop do
 j = area:find( seek, j );
 if j then
 c = area:byte( j, j );
 if c == 123 then -- {
 k = j + 1;
 if area:byte( k, k ) == 123 then
 k = k + 1;
 if area:byte( k, k ) == 123 then
 j, loop = TemplUtl.feed( area, "{{{", k, after );
 else
 k = k - 1;
 j, loop = TemplUtl.feed( area, "{{", k, after );
 end
 if not loop then
 r = j;
 end
 end
 elseif c == 125 then -- }
 k = j + 1;
 if area:byte( k, k ) == 125 then
 if ahead == "{{" then
 r = k;
 break; -- while loop;
 elseif ahead == "{{{" then
 k = k + 1;
 if area:byte( k, k ) == 125 then
 r = k;
 break; -- while loop;
 end
 elseif not ahead then
 r = j - 1;
 loop = false;
 end
 end
 elseif c == 60 then -- <
 k = j + 3;
 if area:sub( j, k ) == "<!--" then
 k = area:find( "-->", k );
 if k then
 j = k + 2;
 end
 else
 local skip;
 s = area:sub( j + 1 ):lower();
 skip = s:match( "^%s*nowiki%s*>" );
 if skip then
 local n = skip:len();
 n, k = s:find( "<%s*/%s*nowiki%s*>", n );
 if k then
 j = j + k;
 else
 loop = false;
 end
 end
 end
 elseif c == 124 then -- |
 if not r then
 r = j - 1;
 end
 if not ahead then
 loop = false;
 end
 elseif c == 91 then -- [
 k = j + 1;
 if area:byte( k, k ) == 91 then
 k = k + 1;
 j, loop = TemplUtl.feed( area, "[[", k, after );
 elseif TemplUtl.feasible( area:sub( k ) ) then
 k = k + 3;
 j, loop = TemplUtl.feed( area, "[", k, after );
 end
 if not loop then
 r = j;
 end
 elseif c == 93 then -- ]
 if ahead == "[" then
 r = j;
 break; -- while loop
 elseif ahead == "[[" then
 k = j + 1;
 if area:byte( k, k ) == 93 then
 r = k;
 break; -- while loop
 end
 end
 elseif c == 58 then -- :
 s = area:sub( j + 1, j + 2 );
 if s == "//" then
 s = " " .. area:sub( 1, j + 2 );
 s = s:match( "%s(%a+://)$" );
 if s and TemplUtl.feasible( s ) then
 s = area .. " ";
 s = s:match( "([^%s|]+)%s", j );
 if s then
 k = s:find( "}}" );
 if k then
 j = j + k + 1;
 else
 j = j + s:len();
 end
 end
 end
 end
 end
 j = j + 1;
 else
 loop = false;
 end
 end -- while loop
 if not r then
 r = area:len();
 end
 return r, loop;
 end -- TemplUtl.feed()



 TemplUtl.feeder = function ( area, at )
 -- Retrieve all parameters
 -- Precondition:
 -- area -- string; template transclusion
 -- at -- optional number; byte position in area of "{{"
 -- Postcondition:
 -- Returns
 -- -- table
 -- [0] -- template, page, parser function name
 -- [1] -- unnamed parameter
 -- ["name"] -- named parameter
 -- -- string; error message, if any, else nil
 local n = 0;
 local j, k, p, r, r2, s, v;
 if type( at ) == "number" then
 j = at + 2;
 else
 j = 3;
 end
 while true do
 k = TemplUtl.feed( area, false, j );
 s = area:sub( j, k );
 s = s:gsub( "<!--.*-->", "" );
 if n == 0 then
 r = { [ 0 ] = s };
 n = 1;
 else
 p, v = s:match( "^([^=]*)=(.*)$" );
 if p then
 if p:match( "^%s*%d+%s*$" ) then
 p = tonumber( p );
 else
 p = mw.text.trim( p );
 end
 v = mw.text.trim( v );
 else
 p = n;
 v = s;
 n = n + 1;
 end
 if r[ p ] then
 if r2 then
 r2 = r2 .. " * ";
 else
 r2 = "";
 end
 r2 = string.format( "%s%s '%s'",
 r2,
 "duplicated parameter",
 tostring( p ) );
 end
 r[ p ] = v;
 end
 s = area:sub( k + 1, k + 2 );
 if s == "}}" then
 break; -- while true
 elseif s == "" then
 r2 = "template not closed";
 break; -- while true
 end
 j = k + 2;
 end -- while true
 return r, r2;
 end -- TemplUtl.feeder()



 TemplUtl.fetch = function ( area, ask )
 -- Find assignment of a named template parameter
 -- Precondition:
 -- area -- string; template transclusion
 -- ask -- string; parameter name
 -- Postcondition:
 -- Returns string with trimmed parameter value, or nil
 -- Does not return value if template inside
 local r;
 local scan = string.format( "%s%s%s",
 "|%s*", ask, "%s*=(.+)$" );
 r = mw.ustring.match( area, scan );
 if r then
 local j = TemplUtl.feed( r, false, 1 );
 r = r:sub( 1, j );
 if r then
 r = mw.text.trim( r );
 if r == "" then
 r = nil;
 end
 end
 end
 return r;
 end -- TemplUtl.fetch()



 TemplUtl.find = function ( area, access, at, alter )
 -- Find next occurrence of a template
 -- Precondition:
 -- area -- string; where to search
 -- access -- string; trimmed (template) title
 -- at -- optional number; ustring position in area, if not 1
 -- alter -- optional string; lowercase namespace pattern
 -- "" for article
 -- no colon (:)
 -- Postcondition:
 -- Returns ustring position of "{{" in area, or false
 -- Requires:
 -- fiatTitleRegExp()
 local scan = string.format( "{{%s%s%s",
 "([%w_%s:]*)%s*",
 fiatTitleRegExp( access ),
 "%s*([|}<]!?)" );
 local r, space, start, suffix;
 if type( at ) == "number" then
 r = at;
 else
 r = 1;
 end
 while true do
 r = mw.ustring.find( area, scan, r );
 if r then
 start, suffix = mw.ustring.match( area, scan, r );
 if start then
 start = mw.text.trim( start );
 if start == "" then
 break; -- while true
 elseif alter then
 if not space then
 space = string.format( "^:?%s:$", alter );
 end
 start = mw.ustring.lower( start );
 if mw.ustring.match( start, space ) then
 break; -- while true
 end
 else
 start = start:match( "^:?(.+):$" );
 if start then
 start = mw.ustring.lower( start );
 if start == "template" then
 break; -- while true
 else
 if not space then
 space = mw.site.namespaces[ 10 ].name;
 space = mw.ustring.lower( space );
 end
 start = start:gsub( "_", " " )
 :gsub( "%s+", " " );
 if start == space then
 break; -- while true
 end
 end
 end
 end
 else
 break; -- while true
 end
 r = r + 2;
 else
 r = false;
 break; -- while true
 end
 end -- while true
 return r;
 end -- TemplUtl.find()


 -- finder()
 -- 1 page name
 -- 2 template title / page name
 -- 3 4 5 6
 -- more like 2



 TemplUtl.firstbreak = function ( adjust )
 -- Precede leading character with newline if specific syntax
 -- Precondition:
 -- adjust -- string; trimmed wikitext
 -- Postcondition:
 -- Returns string, modified if necessary
 return fallible( adjust, true );
 end -- TemplUtl.firstbreak()



 TemplUtl.flat = function ( area )
 -- Remove syntax elements that hide effective syntax only
 -- Precondition:
 -- area -- string; unparsed wikitext to be reduced
 -- Postcondition:
 -- Returns cleared wikitext
 local delimiters = { { "<%s*NOWIKI%s*>", "<%s*/%s*NOWIKI%s*>" },
 { "<!--", "-->", true },
 { "<%s*PRE%s*>", "<%s*/%s*PRE%s*>" },
 { "<%s*SYNTAXHIGHLIGHT[^<>]*>",
 "<%s*/%s*SYNTAXHIGHLIGHT%s*>" } };
 local i = 1;
 local r = area;
 local k, m, n;
 if not TemplUtl.Delimiters then
 local c, sD, sP;
 TemplUtl.Delimiters = { };
 for j = 1, #delimiters do
 table.insert( TemplUtl.Delimiters, { } );
 for ji = 1, 2 do
 sD = delimiters[ j ][ ji ];
 sP = "";
 for js = 1, #sD, 1 do
 c = sD:byte( js, js );
 if c >= 65 and c <= 90 then
 sP = string.format( "%s[%c%c]",
 sP, c, c + 32 );
 else
 sP = sP .. string.char( c );
 end
 end -- for js
 table.insert( TemplUtl.Delimiters[ j ], sP );
 end -- for ji
 end -- for j
 end
 while ( true ) do
 k = false;
 for j = 1, #delimiters do
 m = r:find( TemplUtl.Delimiters[ j ][ 1 ],
 i,
 TemplUtl.Delimiters[ j ][ 3 ] );
 if m and ( not k or m < k ) then
 k = m;
 n = j;
 end
 end -- for j
 if k then
 local s
 if k > 1 then
 i = k - 1;
 s = r:sub( 1, i );
 else
 s = "";
 end
 j, m = r:find( TemplUtl.Delimiters[ n ][ 2 ],
 k + 1,
 TemplUtl.Delimiters[ n ][ 3 ] );
 if m then
 r = s .. r:sub( m + 1 );
 else
 r = s;
 break; -- while true
 end
 else
 break; -- while true
 end
 end -- while true
 return r;
 end -- TemplUtl.flat()



 TemplUtl.nowiki1 = function ( adjust )
 -- HTML-escape leading character if disturbing syntax
 -- Precondition:
 -- adjust -- string; trimmed wikitext
 -- Postcondition:
 -- Returns string, modified if necessary
 return fallible( adjust, false );
 end -- TemplUtl.nowiki1()



 Failsafe.failsafe = function ( atleast )
 -- Retrieve versioning and check for compliance
 -- Precondition:
 -- atleast -- string, with required version
 -- or wikidata|item|~|@ or false
 -- Postcondition:
 -- Returns string -- with queried version/item, also if problem
 -- false -- if appropriate
 -- 2020年08月17日
 local since = atleast
 local last = ( since == "~" )
 local linked = ( since == "@" )
 local link = ( since == "item" )
 local r
 if last or link or linked or since == "wikidata" then
 local item = Failsafe.item
 since = false
 if type( item ) == "number" and item > 0 then
 local suited = string.format( "Q%d", item )
 if link then
 r = suited
 else
 local entity = mw.wikibase.getEntity( suited )
 if type( entity ) == "table" then
 local seek = Failsafe.serialProperty or "P348"
 local vsn = entity:formatPropertyValues( seek )
 if type( vsn ) == "table" and
 type( vsn.value ) == "string" and
 vsn.value ~= "" then
 if last and vsn.value == Failsafe.serial then
 r = false
 elseif linked then
 if mw.title.getCurrentTitle().prefixedText
 == mw.wikibase.getSitelink( suited ) then
 r = false
 else
 r = suited
 end
 else
 r = vsn.value
 end
 end
 end
 end
 end
 end
 if type( r ) == "nil" then
 if not since or since <= Failsafe.serial then
 r = Failsafe.serial
 else
 r = false
 end
 end
 return r
 end -- Failsafe.failsafe()



 -- Export
 local p = { };

 function p.facets( frame )
 return TemplUtl.facets( frame.args[ 1 ] or "",
 frame.args.decode );
 end -- p.facets

 function p.faculty( frame )
 local r = TemplUtl.faculty( frame.args[ 1 ],
 frame.args[ 2 ] );
 if r ~= "-" then
 r = r and "1";
 end
 return r or "";
 end -- p.faculty

 function p.failure( frame )
 local scream = mw.text.trim( frame.args[ 1 ] or "" );
 local loud = frame.args[ 2 ];
 local select = frame.args.class;
 if scream == "" then
 scream = "?????????";
 end
 if loud then
 loud = TemplUtl.faculty( loud, nil );
 end
 return TemplUtl.failure( scream, loud, select, frame );
 end -- p.failure

 function p.fake( frame )
 TemplUtl.fake( frame.args[ 1 ] or "", frame );
 return "";
 end -- p.fake

 function p.fakes( frame )
 local list = ( frame.args.list == "1" );
 local r = TemplUtl.fakes( frame.args,
 frame,
 frame.args.prefix,
 list );
 return r or "";
 end -- p.fakes

 function p.firstbreak( frame )
 local r = ( frame.args[ 1 ] );
 if r then
 r = mw.text.trim( r );
 if r ~= "" then
 r = TemplUtl.firstbreak( r );
 end
 end
 return r or "";
 end -- p.firstbreak

 function p.from( frame )
 local r = frame:getParent():getTitle();
 if r then
 r = string.format( "&#123;&#123;%s&#125;&#125;", r );
 end
 return r or "";
 end -- p.from

 function p.isRedirect()
 return mw.title.getCurrentTitle().isRedirect and "1" or "";
 end -- p.isRedirect

 function p.nowiki1( frame )
 local r = ( frame.args[ 1 ] );
 if r then
 r = mw.text.trim( r );
 if r ~= "" then
 r = TemplUtl.nowiki1( r );
 end
 end
 return r or "";
 end -- p.nowiki1

 p.failsafe = function ( frame )
 -- Versioning interface
 local s = type( frame )
 local since
 if s == "table" then
 since = frame.args[ 1 ]
 elseif s == "string" then
 since = frame
 end
 if since then
 since = mw.text.trim( since )
 if since == "" then
 since = false
 end
 end
 return Failsafe.failsafe( since ) or ""
 end -- p.failsafe

 p.TemplUtl = function ()
 return TemplUtl;
 end -- p.TemplUtl()

 setmetatable( p, { __call = function ( func, ... )
 setmetatable( p, nil );
 return Failsafe;
 end } );

 return p;