--
-- melisma - extensible and scriptable audio engine
-- Copyright (C) 2026  Ludvig Gunne Lindström
--
-- This program is free software: you can redistribute it and/or modify
-- it under the terms of the GNU General Public License as published by
-- the Free Software Foundation, either version 3 of the License, or
-- (at your option) any later version.
--
-- This program is distributed in the hope that it will be useful,
-- but WITHOUT ANY WARRANTY; without even the implied warranty of
-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-- GNU General Public License for more details.
--
-- You should have received a copy of the GNU General Public License
-- along with this program.  If not, see <https://www.gnu.org/licenses/>.
--

local module = {}

function module.render(layout)
  local lines = {}

  local function append(format,...)
    local line = string.format(format,...)
    table.insert(lines,line)
  end

  append('digraph {')
  append('rankdir=BT')
  append('node [shape=rect]')

  for id,node in pairs(layout) do
    append('"%s" [label="%s"]',id,node.label or '?')
  end

  for id,node in pairs(layout) do
    for _,input in ipairs(node.inputs) do
      append('"%s" -> "%s"',input,id)
    end
  end

  append('}')

  return table.concat(lines,'\n')
end

return module