-- This is released into the public domain.
-- No warranty is provided, implied or otherwise.

-- Used by filedialog to provide a sane relative environment.
-- Essentially, the filedialog is just a 'thin' UI wrapper over this.
-- Returns the root node.

local function dialog(name, parent)
 return {
  name = name,
  list = function () return {{"Back", function () return nil, parent end}} end,
  unknownAvailable = false,
  selectUnknown = function (text) end   
 }
end

local getFsNode, getRoot
local setupCopyNode
function setupCopyNode(parent, myRoot, op, complete, impliedName)
 local function handleResult(aRes, res)
  if aRes then
   return complete(res, true)
  else
   return nil, setupCopyNode(parent, res, op, complete, impliedName)
  end
 end
 return {
  name = "(" .. op .. ") " .. myRoot.name,
  list = function ()
   local l = {}
   table.insert(l, {"Cancel Operation: " .. op, function ()
    complete(nil, false)
    return false, parent
   end})
   if impliedName and myRoot.unknownAvailable then
    table.insert(l, {"Implied: " .. impliedName, function ()
     return handleResult(myRoot.selectUnknown(impliedName))
    end})
   end
   for _, v in ipairs(myRoot.list()) do
    table.insert(l, {v[1], function ()
     return handleResult(v[2]())
    end})
   end
   return l
  end,
  unknownAvailable = myRoot.unknownAvailable,
  selectUnknown = function (tx)
   return handleResult(myRoot.selectUnknown(tx))
  end
 }
end
local function setupCopyVirtualEnvironment(fs, parent, fwrap, impliedName)
 if not fwrap then
  return false, dialog("Could not open source", parent)
 end
 local myRoot = getRoot(fs, true)
 -- Setup wrapping node
 return setupCopyNode(parent, myRoot, "Copy", function (fwrap2, intent)
  if not fwrap2 then
   fwrap.close()
   if intent then
    return false, dialog("Could not open dest.", parent)
   end
   return false, parent
  end
  local data = fwrap.read(neo.readBufSize)
  while data do
   fwrap2.write(data)
   data = fwrap.read(neo.readBufSize)
  end
  fwrap.close()
  fwrap2.close()
  return false, dialog("Completed copy.", parent)
 end, impliedName)
end
function getFsNode(fs, parent, fsc, path, mode)
 local va = fsc.address:sub(1, 4)
 local fscrw = not fsc.isReadOnly()
 local dir = path:sub(#path, #path) == "/"
 local confirmedDel = false
 local t
 t = {
  name = ((dir and "DIR: ") or "FILE: ") .. va .. path,
  list = function ()
   local n = {}
   n[1] = {"..", function ()
    return nil, parent
   end}
   if dir then
    for k, v in ipairs(fsc.list(path)) do
     local nm = "F: " .. v
     local fp = path .. v
     if fsc.isDirectory(fp) then
      nm = "D: " .. v
     end
     n[k + 1] = {nm, function () return nil, getFsNode(fs, t, fsc, fp, mode) end}
    end
   end
   if fscrw then
    if dir then
     table.insert(n, {"Mk. Directory", function ()
      return nil, {
       name = "MKDIR...",
       list = function () return {{
        "Cancel", function ()
         return false, t
        end
       }} end,
       unknownAvailable = true,
       selectUnknown = function (text)
        fsc.makeDirectory(path .. text)
        return nil, dialog("Done!", t)
       end
      }
     end})
    else
     if mode ~= nil then
      local tx = "Open"
      if mode == true then
       tx = "Save"
      elseif mode == "append" then
       tx = "Append"
      end
      if fscrw or mode == false then
       table.insert(n, {tx, function ()
        local rt, re = require("sys-filewrap").create(fsc, path, mode)
        if not rt then
         return false, dialog("Open Error: " .. tostring(re), parent)
        end
        return true, rt
       end})
      end
     end
     table.insert(n, {"Copy", function ()
      local rt, re = require("sys-filewrap").create(fsc, path, false)
      if not rt then
       return false, dialog("Open Error: " .. tostring(re), parent)
      end
      return nil, setupCopyVirtualEnvironment(fs, parent, rt, path:match("[^/]*$") or "")
     end})
    end
    if path ~= "/" then
     local delText = "Delete"
     if confirmedDel then
      delText = "Delete <ARMED>"
     end
     table.insert(n, {delText, function ()
      if not confirmedDel then
       confirmedDel = true
       return nil, t
      end
      fsc.remove(path)
      return nil, dialog("Done.", parent)
     end})
    else
     table.insert(n, {"Relabel Disk", function ()
      return nil, {
       name = "Disk Relabel...",
       list = function () return {{
        fsc.getLabel() or "Cancel",
        function ()
         return false, t
        end
       }} end,
       unknownAvailable = true,
       selectUnknown = function (tx)
        fsc.setLabel(tx)
        return false, t
       end
      }
     end})
    end
   end
   return n
  end,
  unknownAvailable = dir and (mode ~= nil) and ((mode == false) or fscrw),
  selectUnknown = function (text)
   local rt, re = require("sys-filewrap").create(fsc, path .. text, mode)
   if not rt then
    return false, dialog("Open Error: " .. tostring(re), parent)
   end
   return true, rt
  end
 }
 return t
end
function getRoot(fs, mode)
 local t
 t = {
  name = "DRVS:",
  list = function ()
   local l = {}
   for fsi in fs.list() do
    local id = fsi.getLabel()
    if fsi == fs.primary then
     id = "NEO" .. ((id and (":" .. id)) or " Disk")
    elseif fsi == fs.temporary then
     id = "RAM" .. ((id and (" " .. id)) or "Disk")
    else
     id = id or "Disk"
    end
    local used, total = fsi.spaceUsed(), fsi.spaceTotal()
    local amount = string.format("%02i", math.ceil((used / total) * 100))
    local mb = math.floor(total / (1024 * 1024))
    if fsi.isReadOnly() then
     id = "RO " .. amount .. "% " .. mb .. "M " .. id
    else
     id = "RW " .. amount .. "% " .. mb .. "M " .. id
    end
    table.insert(l, {fsi.address:sub(1, 4) .. " " .. id, function ()
     return nil, getFsNode(fs, t, fsi, "/", mode)
    end})
   end
   return l
  end,
  unknownAvailable = false,
  selectUnknown = function (text)
   return false, dialog("Ow, that hurt...", t)
  end
 }
 return t
end
return getRoot