--[[nef_20221122  NEAREST
This utility can be used to quickly identify all cities that are candidates to become the 'owner' of units that belonged to the indicated city if it was disbanded.  Special reporting is used to facilitate opening the city DB`s.  The argument is the city that could be disbanded. (Userdata or featured text link)

Module requires the FEATURED_TEXT, PARSER and SUPPORT_extended.

]]
do             -- NEAREST
-- SOH   
   local featured = setmetatable({},{  -- FEATURED_TEXT
     __index = function(t,k) local ft = assert(log.featured, 'Featured text not loaded')
       return assert(ft[k], 'Featured '..k..' not loaded.'  ) end;}) 
   local function color (...) color = featured.color; return color (...) end
   local function link  (...) link  = featured.link;  return link  (...) end
   local function bbcode(...) 
                bbcode       = featured.bbcode; return bbcode      (...) end
                
   local SP       = setmetatable({},{  -- SUPPORT_basic
     __index = function(t,k) local SP = assert(game.SP, 'Support package not loaded')
       return assert(SP[k], 'Support '..k..' not loaded.') end;}) 
   local function user  (...) user   = SP.user;       return user  (...) end
   local function background(...) 
                background   = SP.background;   return background  (...) end
   local function colored_link(...) 
                colored_link = SP.colored_link; return colored_link(...) end
-- SUPPORT_extended
   local function get_link_bb(...)
                get_link_bb  = SP.get_link_bb;  return get_link_bb (...) end
-- STX
   local report  = function(tile,...)
     if chat then chat.msg(...)     log.normal(...)
     else notify.event(user(),tile,E.BROADCAST_REPORT,...) end
   end
   local report2 = function(tile,...)
     if chat then chat.msg(...)     log.normal(...)
     else notify.event(user(),tile,E.TECH_LOST,...) end
   end

-- Tile     (Tile):square_iterate     (number (chebyshev radius) )
-- number  	(Player):num_cities	      ()		
   function nearest(city); city = get_link_bb(city)   
     if tolua.type(city) ~= 'City'
     then return report(nil, 'Argument not a city reference')
     end; local player, city_tile = city.owner, city.tile
     if    player:num_cities() == 1
     then  report(city_tile, colored_link(city,'No other cities')) 
     else  report(city_tile,
             color(link(city,'Nearest cities to '..(city.name)),nil,background(city)))
           local  distance = 0
           repeat distance = distance + 1
             for  tile in city_tile:square_iterate (distance) do
               local city = tile:city()
               if    tile ~= city_tile and city and city.owner == player 
               then  report2(tile,colored_link(city) ); distance = -1
               end
             end
           until distance < 0
     end
   end
--ETX
end  
--------      end NEAREST