--[[

  $Id: $
  $DateTime: $
  $Author: $
  $Change: $

]]--


--[[
This is a Lua script for validating the size of a form field.
The field size is counted as number of bytes, so for some UTF characters,
one character might be longer than one byte.
It allows instance configuration to choose a form, form-field and a
minimum-size for the field.
If the field value is shorter that the expected size, the extension
will fail the command with a message to the user.
]]--


package.path = Helix.Core.Server.GetArchDirFileName( "?.lua" )
local utils = require "ExtUtils"
local initDone = false

local validForms = { branch = 1, client = 1, label = 1, protect = 1,
                     triggers = 1, change = 1 }

function init()
  if not initdone then
    initDone = 1
    utils.init()
  end
end

function GlobalConfigFields()
  return { "" }
end

function InstanceConfigFields()
 --formType = "the spec to validate field size in - e.g. branch/label/protect",
 --formField = "the field in the form to validate",
 --minSize = "minimum size for the field value to accept"
  return {
    formType =
      "The form type to check: branch/client/label/protect/triggers/change",
    formField = "The field to check, e.g. Description/Type/Status",
    minSize   = "minimum field size to accept"
  }
end

function InstanceConfigEvents()
  init()

  local form = utils.iCfgData[ "formType" ]

  if form == nil or validForms[ form ] == nil then
    return false
  end

  return { ["form-in"] = form }

end

function FormIn()
  init()

  local form = utils.iCfgData[ "formType" ]
  
  if form == nil or validForms[ form ] == nil then
    local msg = "form = '".. form .."'\n"
    if form == nil then error( "nil form" ) end
    if validForms[ form ] == nil then
        msg = msg .. "validForms[ form ] == nil\n"
        error( "Invalid form selected:" .. msg )
    end
  end

  local field = utils.iCfgData[ "formField" ]
  local minsz = utils.iCfgData[ "minSize" ]
  local file = Helix.Core.Server.GetVar( "formfile" );

  local f = io.open( file, "r" )
  if f == nil then
    error( "Upexpected error, form file does not exist:" ..
            file .. "\n" )
  end

  local contents = f:read( "*all" )
  local p4 = P4.P4:new()
  local parsed = p4:parse_spec( form, contents )
  local val = parsed[ field ]
  val = trim( val )

  if val:len() < tonumber( minsz ) then
    Helix.Core.Server.SetClientMsg( "Field '" .. field .. "' minimum size is "
                                .. minsz .. ", '" .. val ..  "' is too short." )
    return false
  end

  return true
end