-- This code map library has a number of useful helper routines for doing mapping and checking codes etc.
 
local codemap = {}
 
-- Make a set
-- MySet = codemap.set{"Fred", "Bruce", "Jim"}
-- if MySet[Msg.PID[3][1][1]] then print('One of our three amigos') end
function codemap.set(a)
   local m = {}
   for _,v in ipairs(a) do m[v] = true end
   return codemap.map(m, false)
end
 
-- Create a map the advantage of this function is that it will take a tree node without
-- needing to convert it to a string. Example of usage
-- SexMap = codemap.map({'M'='Male', 'm'='Male', 'F'='Female', 'f'='Female'},'defaultValue')
function codemap.map(m, default)
   return setmetatable(m, {
         __index = function(m,k)
            if type(k) ~= 'string' then
               local v = rawget(m, tostring(k))
               if v ~= nil then return v end
            end
            return default
         end})
end

local codemap_map = {
   Title="codemap.map";
   Usage="codemap.map({codemap} [, default])",
   SummaryLine="Create a codemap table to map one set of codes to another",
   Desc=[[Create a codemap table to map one set of codes to another.
   <p>You can add a default value to the codeset to match unknown values, 
   if no default is used then <b>nil</b> is returned.
   <br><br><b>Note</b>: This function uses Lua metatables - but you do not need to 
   understand this to use it.
   ]];
   ParameterTable= true,
   Parameters= {
      {codemap= {Desc='Table containing the code mappings <u>table</u>.'}},
      {default= {Desc='Default return if no match is found <u>string</u>.', Opt = true}},
   };
   Returns = {
      {Desc="Returns a codeset table for mapping codes <u>table</u>."},
   };
   Examples={
      [[   -- using a default codemap value
   local SexCodeMap = codemap.map({
      M='Male',
      m='Male',
      F='Female',
      f='Female'
   }, 'Other')    -- default = 'Other'

   -- use the map you created to convert codes
   trace(SexCodeMap['M']) --> 'Male'
   trace(SexCodeMap['W']) --> 'Other'
   ]],
      [[   -- without a default codemap value
   local SexCodeMap = codemap.map({
      M='Male',
      m='Male',
      F='Female',
      f='Female'
   })             -- no default

   -- use the map you created to convert codes
   trace(SexCodeMap['M']) --> 'Male'
   trace(SexCodeMap['W']) --> nil
   ]],
   };
   SeeAlso={
      {
         Title="codemap.lua - in our code repository",
         Link="http://help.interfaceware.com/code/details/codemap-lua"
      },
      {
         Title="Codemap example",
         Link="http://help.interfaceware.com/v6/codemap-example"
      }
   }
}

help.set{input_function=codemap.map, help_data=codemap_map}

local codemap_set = {
   Title="codemap.set";
   Usage="codemap.set{codemap}",
   SummaryLine="Create a codemap table to use for membership checking",
   Desc=[[Create a codemap table to use for membership checking.<p> The codemap.set()
   function uses codemap.map() to create a codemap table with known 
   values set to <b>true</b> and a default of <b>false</b> for unknown
   values.
   ]];
   ParameterTable= true,
   Parameters= {
      {codeset= {Desc='Set of valid codes to use for membership checking <u>table</u>.'}},
   };
   Returns = {
      {Desc="Returns a mapping table for membership checking <u>table</u>."},
   };
   Examples={
      [[   local AmigoSet = codemap.set{"Fred", "Jim", "Harry"}

   -- Check for set membership
   trace(AmigoSet['Fred']) --> true
   trace(AmigoSet['Mary']) --> false
   ]],
   };
   SeeAlso={
      {
         Title="codemap.lua - in our code repository",
         Link="http://help.interfaceware.com/code/details/codemap-lua"
      },
      {
         Title="Codemap example",
         Link="http://help.interfaceware.com/v6/codemap-example"
      }
   }
}

help.set{input_function=codemap.set, help_data=codemap_set}

return codemap