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Módulo:Template wrapper

Permanently protected module
Origem: Wikipédia, a enciclopédia livre.

require('strict')

local error_msg = '<span style=\"font-size:100%\" class=\"error\"><code style=\"color:inherit; border:inherit; padding:inherit;\">&#124;_template=</code> missing or empty</span>';


--[[--------------------------< I S _ I N _ T A B L E >--------------------------------------------------------

scan through tbl looking for value; return true if found, false else

]]

local function is_in_table (tbl, value)
    for k, v in pairs (tbl) do
        if v == value then return true end
    end
    return false;
end


--[[--------------------------< A D D _ P A R A M E T E R >----------------------------------------------------

adds parameter name and its value to args table according to the state of boolean list argument; kv pair for
template execution; k=v string for template listing.

]]

local function add_parameter (k, v, args, list)
    if list then
        table.insert( args, table.concat ({k, '=', v}));                        -- write parameter names and values to args table as string
    else
        args[k] = v;                                                            -- copy parameters to args table
    end
end


--[[--------------------------< A L I A S _ M A P _ G E T >----------------------------------------------------

returns a table of local template (parent frame) parameter names and the target template names that match where
in [key]=<value> pairs where:
    [key] is local template parameter name (an alias)
    <value> is target template parameter name (the canonical parameter name used in the working template)

The parameter |_alias-map= has the form:
    |_alias-map=<list>
where <list> is a comma-separated list of alias / canonical parameter name pairs in the form
    <from> : <to>
where:
    <from> is the local template's parameter name (alias)
    <to> is the target template's parameter name (canonical)
    for enumerated parameters place an octothorp (#) where the enumerator digits are placed in the parameter names:
        <from#> : <to#>

]]

local function alias_map_get (_alias_map)
    local T = mw.text.split (_alias_map, '%s*,%s*');                            -- convert the comma-separated list into a table of alias pairs
    local mapped_aliases = {};                                                    -- mapped aliases will go here
    local l_name, t_name;                                                        -- parameter names
    
    for _, alias_pair in ipairs (T) do                                            -- loop through the table of alias pairs
        l_name, t_name = alias_pair:match ('(.-)%s*:%s*(.+)');                    -- from each pair, get local and target parameter names
        if l_name and t_name then                                                -- if both are set
            if tonumber (l_name) then
                l_name = tonumber (l_name);                                        -- convert number-as-text to a number
            end
            mapped_aliases[l_name] = t_name;                                    -- add them to the map table
        end
    end

    return mapped_aliases;
end


--[[--------------------------< F R A M E _ A R G S _ G E T >--------------------------------------------------

Fetch the wrapper template's 'default' and control parameters; adds default parameters to args

returns content of |_template= parameter (name of the working template); nil else

]]

local function frame_args_get (frame_args, args, list)
    local template;

    for k, v in pairs (frame_args) do                                            -- here we get the wrapper template's 'default' parameters
        if 'string' == type (k) and (v and ('' ~= v)) then                        -- do not pass along positional or empty parameters
            if '_template' == k then
                template = v;                                                    -- save the name of template that we are wrapping
            elseif '_exclude' ~= k and '_reuse' ~= k and '_include-positional' ~= k  and '_alias-map' ~= k then    -- these already handled so ignore here;
                add_parameter (k, v, args, list);                                -- add all other parameters to args in the style dictated by list
            end
        end
    end

    return template;                                                            -- return contents of |_template= parameter
end


--[=[--------------------------< P F R A M E _ A R G S _ G E T >------------------------------------------------

Fetches the wrapper template's 'live' parameters; adds live parameters that aren't members of the exclude table to
args table; positional parameters may not be excluded

no return value

]=]

local function pframe_args_get (pframe_args, args, exclude, _include_positional, list)
    for k, v in pairs (pframe_args) do
        if 'string' == type (k) and not is_in_table (exclude, k) then            -- do not pass along excluded parameters
            if v and ('' ~= v) then                                                -- pass along only those parameters that have assigned values
                if 'unset' == v:lower() then                                    -- special keyword to unset 'default' parameters set in the wrapper template
                    v = '';                                                        -- unset the value in the args table
                end
                add_parameter (k, v, args, list)                                -- add all other parameters to args in the style dictated by list; alias map only supported for local-template parameters
            end
        end
    end

    if _include_positional then
        for i, v in ipairs (pframe_args) do                                        -- pass along positional parameters
            if 'unset' == v:lower() then                                        -- special keyword to unset 'default' parameters set in the wrapper template
                v = '';                                                            -- unset the value in the args table
            end
            add_parameter (i, v, args, list);
        end
    end
end


--[[--------------------------< _ M A I N >--------------------------------------------------------------------

Collect the various default and live parameters into args styled according to boolean list.

returns name of the working or listed template or nil for an error message

]]

local function _main (frame, args, list)
    local template;
    local exclude = {};                                                            -- table of parameter names for parameters that are not passed to the working template
    local reuse_list = {};                                                        -- table of pframe parameter names whose values are modified before they are passed to the working template as the same name
    local alias_map = {};                                                        -- table that maps parameter aliases to working template canonical parameter names
    local _include_positional;
    
    if frame.args._exclude and ('' ~= frame.args._exclude) then                    -- if there is |_exclude= and it's not empty
        exclude = mw.text.split (frame.args._exclude, "%s*,%s*");                -- make a table from its contents
    end
                                                                                -- TODO: |_reuse= needs a better name (|_reuse=)
    if frame.args._reuse and ('' ~= frame.args._reuse) then                    -- if there is |_reuse= and it's not empty
        reuse_list = mw.text.split (frame.args._reuse, "%s*,%s*");                -- make a table from its contents
    end

    if frame.args['_alias-map'] and ('' ~= frame.args['_alias-map']) then        -- if there is |_alias-map= and it's not empty
        alias_map = alias_map_get (frame.args['_alias-map']);                    -- make a table from its contents
    end

    template = frame_args_get (frame.args, args, list);                            -- get parameters provided in the {{#invoke:template wrapper|...|...}}
    if nil == template or '' == template then                                    -- this is the one parameter that is required by this module
        return nil;                                                                -- not present, tell calling function to emit an error message
    end
    
    _include_positional = 'yes' == frame.args['_include-positional'];            -- when true pass all positional parameters along with non-excluded named parameters to ...
                                                                                -- ... the working template; positional parameters are not excludable
                                                                                
    local _pframe_args = frame:getParent().args;                                -- here we get the wrapper template's 'live' parameters from pframe.args
    local pframe_args = {};                                                        -- a local table that we can modify

    for k, v in pairs (_pframe_args) do                                            -- make a copy that we can modify
        pframe_args[k] = v;
    end
    
-- here we look for pframe parameters that are aliases of canonical parameter names; when found
-- we replace the alias with the canonical.  We do this here because the reuse_list works on
-- canonical parameter names so first we convert alias parameter names to canonical names and then
-- we remove those canonical names from the pframe table that are reused (provided to the working
-- template through the frame args table)

    for k, v in pairs (alias_map) do                                            -- k is alias name, v is canonical name
        if pframe_args[k] then                                                    -- if pframe_args has parameter with alias name
            pframe_args[v] = _pframe_args[k];                                    -- create new canonical name with alias' value
            pframe_args[k] = nil;                                                -- unset the alias
        end
    end

    for k, v in pairs (pframe_args) do                                            -- do enumerated parameter alias -> canonical translation
        if 'string' == type (k) then                                            -- only named parameters can be enumerated
            if alias_map[k..'#'] then                                            -- non-enumerated alias matches enumerated parameter pattern? enumerator at end only
                pframe_args[alias_map[k..'#']:gsub('#', '')] = v;                -- remove '#' and copy parameter to pframe_args table
                pframe_args[k] = nil;                                            -- unset the alias
            elseif k:match ('%d+') then                                            -- if this parameter name contains digits
                local temp = k:gsub ('%d+', '#');                                -- make a copy; digits replaced with single '#'
                local enum = k:match ('%d+');                                    -- get the enumerator
                
                if alias_map[temp] then                                            -- if this parameter is a recognized enumerated alias
                    pframe_args[alias_map[temp]:gsub('#', enum)] = v;            -- use canonical name and replace '#' with enumerator and add to pframe_args
                    pframe_args[k] = nil;                                        -- unset the alias
                end
            end
        end
    end

-- pframe parameters that are _reused are 'reused' have the form something like this:
--    |chapter=[[wikisource:{{{chapter}}}|{{{chapter}}}]]
-- where a parameter in the wrapping template is modified and then passed to the working template
-- using the same parameter name (in this example |chapter=)

                                                                                -- remove parameters that will be reused
    for k, v in ipairs (reuse_list) do                                            -- k is numerical index, v is canonical parameter name to ignore
        if pframe_args[v] then                                                    -- if pframe_args has parameter that should be ignored
            pframe_args[v] = nil;                                                -- unset the ignored parameter
        end
    end

    pframe_args_get (pframe_args, args, exclude, _include_positional, list);    -- add parameters and values to args that are not listed in the exclude table

    return template;                                                            -- args now has all default and live parameters, return working template name
end


--[[--------------------------< W R A P >----------------------------------------------------------------------

Template entry point.  Call this function to 'execute' the working template

]]

local function wrap (frame)
    local args = {};                                                            -- table of default and live parameters and their values to be passed to the wrapped template
    local template;                                                                -- the name of the working template

    template = _main (frame, args, false);                                        -- get default and live parameters and the name of the working template
    if not template then                                                        -- template name is required
        return error_msg;                                                        -- emit error message and abandon if template name not present
    end

    return frame:expandTemplate {title=template, args=args};                    -- render the working template
end


--[[--------------------------< L I S T >----------------------------------------------------------------------

Template entry point.  Call this function to 'display' the source for the working template.  This function added
as a result of a TfD here: Wikipedia:Templates_for_discussion/Log/2018_April_28#Module:PassArguments

This function replaces a similarly named function which was used in {{cite compare}} and {{cite compare2}}

Values in the args table are numerically indexed strings in the form 'name=value'

]]


local function list (frame)
    local args = {};                                                            -- table of default and live parameters and their values to be passed to the listed template
    local template;                                                                -- the name of the listed template

    template = _main (frame, args, true);                                        -- get default and live parameters and the name of the listed template
    if not template then                                                        -- template name is required
        return error_msg;                                                        -- emit error message and abandon if template name not present
    end

    return frame:preprocess (table.concat ({'<code style="color:inherit; background:inherit; border:none;"><nowiki>{{', template, ' |', table.concat( args, ' |' ), '}}</nowiki></code>'}));    -- render the template
end


--[[--------------------------< E X P O R T E D   F U N C T I O N S >------------------------------------------
]]

return {
    list = list,
    wrap = wrap,
    };