--[[nef_20221122 FEATURED_TEXT
Assorted utilities to support featured text displayed in chat log and client
Lua console. Basic functions provided by bbcode, color, link, and link_tile.

bbcode:     simple 'buis' codes.
color:      foreground and/or background colors.
link:       hot link to userdata objects Tile, Unit, or City.
link_tile:  provides a Tile link for Unit or City (use this if the object is
            being destroyed).
link_quick: creates a short form link using a unique name for the default.

link, link_tile, link_quick take an optional 2nd argument for user supplied
text. default is city name or unit type (for link, link_tile).

also included
ftext:      the internal table (called as a function) used to generate default
            text.
]]
do       ----    FEATURED_TEXT
   local _G = _G
      
   local _ENV = _ENV
      
   local MF      = _G.math.floor
   local type    = _G.tolua.type
   local MT_txt  = {
     __index = function () return function () return '' end                   end;
     __call  = function(t,v) local Type = type(v) return t[Type](v),Type      end;
                   }
   local ids    = setmetatable( {
     Tile = function(object) return " x="..MF(object.x).." y="..MF(object.y)  end;
     Unit = function(object) return   " id="..  MF(object.id)                 end;
     City = function(object) return   " id="..  MF(object.id)                 end;
                                },MT_txt );
   local prefix = function(id, Type) 
     return ("[link tgt=%q"):format(Type:lower())..id                         end;
   local ft     = function(object, text) local id, Type = ids (object)
     return id == '' and '' or prefix(id, Type) .. ("]%s[/l]"):format(text)   end;
     
   local function DUP(t) return t,t end

   local _ENV = _ENV
   _ENV   = _G.log --[[ disable this if you want featured to be global;
                        or change it to any other global table.]]
   _ENV, featured = DUP {}
   ftext      = _G.setmetatable( {
     Tile = function(object) return '('..MF(object.x)..','..MF(object.y)..')' end;
     Unit = function(object) return   object.utype:name_translation()         end;
     City = function(object) return     object.name                           end;
                              },MT_txt);
   bbcode     = function(bb,text) 
                  return "["..bb.."]"..text.."[/"..bb.."]"                    end;
   color      = function(text, fg, bg) return "[color" ..                     
                (fg and (" fg=%q"):format(fg) or "") ..                       
                (bg and (" bg=%q"):format(bg) or "") ..                       
                ']'..text.."[/c]"                                             end;
   link_short = function(object,text) local id, Type = ids (object)           
                  return id == '' and ''  or prefix(id, Type) .. id ..        
                       (text and ('name=%q '):format(text) or '')..'/]'       end;
   link       = function(object, text)                                        
                  return ft(object,                text or ftext (object))    end; 
   link_tile  = function(object, text)                                        
                  return ft(object.tile or object, text or ftext (object))    end;
end               
-----------  end FEATURED_TEXT