%% @author Marc Worrell <marc@worrell.nl>
%% @copyright 2014 Marc Worrell
%% @doc Explain template selection.

%% Copyright 2014 Marc Worrell
%%
%% Licensed under the Apache License, Version 2.0 (the "License");
%% you may not use this file except in compliance with the License.
%% You may obtain a copy of the License at
%%
%%     http://www.apache.org/licenses/LICENSE-2.0
%%
%% Unless required by applicable law or agreed to in writing, software
%% distributed under the License is distributed on an "AS IS" BASIS,
%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
%% See the License for the specific language governing permissions and
%% limitations under the License.

-module(z_development_template).

-export([
    event/2
    ]).

-include_lib("zotonic_core/include/zotonic.hrl").
-include_lib("template_compiler/include/template_compiler.hrl").

event(#submit{message=explain_tpl}, Context) ->
    case z_acl:is_allowed(use, mod_development, Context) of
        true ->
            CatName = z_context:get_q(<<"tpl_cat">>, Context, <<>>),
            TplName = z_string:trim(z_context:get_q(<<"tpl_name">>, Context)),
            Tpl = index_props(find_template(CatName, TplName, Context)),
            Vars = [
                {tpl, Tpl}
            ],
            Context1 = z_render:update(
                            "explain-tpl-output",
                            #render{template="_development_template.tpl", vars=Vars},
                            Context),
            z_render:wire({fade_in, [{target, "explain-tpl-output"}]}, Context1);
        false ->
            z_render:growl(?__("You are not allowed to use the template debugging.", Context), Context)
    end.

find_template(<<>>, TplName, Context) ->
    z_module_indexer:find(template, TplName, Context);
find_template(CatName, TplName, Context) ->
    IsA = m_category:is_a(CatName, Context),
    z_template_compiler_runtime:map_template({cat, TplName, IsA}, #{}, Context).

index_props({error, _}) ->
    undefined;
index_props({ok, #template_file{ filename = Path}}) ->
    [
        {module, <<>>},
        {path, Path}
    ];
index_props({ok, #module_index{filepath=Path, module=Module}}) ->
    [
        {module, Module},
        {path, Path}
    ].