function widget:GetInfo()
  return {
    name      = "SpecMode",
    desc      = "coming soon",
    author    = "MelTraX",
    date      = "Mar 21, 2007",
    license   = "GNU GPL, v2 or later",
    layer     = 0,
    enabled   = false
  }
end

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

local SECTOR_WIDTH = 500
local SECTOR_HEIGHT = 500

local IDLE_THRESHOLD = 100

local CHECK_EVERY = 5
local DECAY_EVERY = 100
local DECAY_BY = 1.5

local TRANSITION_DURATION = 2

local HEALTH_GAIN_TO_LOSS_FACTOR = 20

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

include("colors.h.lua")
include("keysym.h.lua")
include("utils.lua")

local inSpecMode = false
local newPointAdded = false
local frameCounter = 0
local teams = {}
local unitHealths = {}
local sectorHealthChanges = {}

local sectorX = 0
local sectorY = 0
local maxValue = 0

local function EnterSpecMode()
  inSpecMode = true
  Spring.SendCommands({"hideinterface", "showhealthbars"}) --, "viewrot"
end
local function LeaveSpecMode()
  inSpecMode = false
  Spring.SendCommands({"hideinterface", "showhealthbars"}) --, "viewta"
end

local function HealthChange(unit, difference)
  if difference > 0 then
    difference = difference / -HEALTH_GAIN_TO_LOSS_FACTOR
  end
  local x, y, z = Spring.GetUnitPosition(unit)
  if sectorHealthChanges[math.floor(x/SECTOR_WIDTH+1)] then
    local oldDif = sectorHealthChanges[math.floor(x/SECTOR_WIDTH+1)][math.floor(z/SECTOR_HEIGHT+1)] or 0
    sectorHealthChanges[math.floor(x/SECTOR_WIDTH+1)][math.floor(z/SECTOR_HEIGHT+1)] = oldDif + difference
  end
end
local function CheckMostActiveSector()
  sectorX = 0
  sectorY = 0
  maxValue = 0
  for i,v in ipairs(sectorHealthChanges) do
    for j,w in pairs(v) do
      if -w > maxValue then
        maxValue = -w
        sectorX = i
        sectorY = j
      end
    end
  end
end

local function UpdateCamera()
  if maxValue > IDLE_THRESHOLD then
    local realX = (sectorX - 0.5) * SECTOR_WIDTH
    local realY = (sectorY - 0.5) * SECTOR_HEIGHT
    local currentCamState = Spring.GetCameraState()
    currentCamState[2] = realX
    currentCamState[4] = realY
    Spring.SetCameraState(currentCamState, TRANSITION_DURATION)
  end
end
function widget:Initialize()
  teams = Spring.GetTeamList()
  local mapX = math.floor(Game.mapX * 500 / SECTOR_WIDTH  + 1)
  local mapY = math.floor(Game.mapY * 500 / SECTOR_HEIGHT + 1)
  for i=1,mapX do
    sectorHealthChanges[i] = {}
  end
  --EnterSpecMode()
end
function widget:TextCommand(command)
  if (command == 'specmode' or command == 'specmode 1') and not inSpecMode then
    EnterSpecMode()
    return false
  elseif (command == 'specmode' or command == 'specmode 0') and inSpecMode then
    LeaveSpecMode()
  end
  local cmd = string.sub(command, 10)
  return true
end
function widget:KeyPress(key, mods, isRepeat)
  if key == KEYSYMS.ESCAPE and inSpecMode and
       not (mods.alt or mods.ctrl or mods.meta or mods.shift) then
    LeaveSpecMode()
    return true
  end
  return false
end
--[[
function widget:AddConsoleLine(line)
  if not inSpecMode then
    return
  end
  if string.find(line, "added point") then
    newPointAdded = true
  end
end
function widget:UnitDestroyed(unitID, unitDefID, unitTeam)
  if inSpecMode and UnitDefs[unitDefID].springCategories.weapon then
    Spring.SendCommands({"specteam " .. Spring.GetUnitTeam(unitID)})
    local currentCamState = Spring.GetCameraState()
    local x, y, z = Spring.GetUnitPosition(unitID)
    currentCamState[2] = x
    currentCamState[4] = z
    Spring.SetCameraState(currentCamState, 2)
  end
end
]]
function widget:Update()
  if not inSpecMode then
    return
  end
  frameCounter = frameCounter + 1
  if newPointAdded then
    Spring.SendCommands({"LastMsgPos"})
    newPointAdded = false
  end
  if math.mod(frameCounter, DECAY_EVERY) == 0 then
    for i,v in ipairs(sectorHealthChanges) do
      for j,w in pairs(v) do
        v[j] = w/DECAY_BY
      end
    end
  end
  local currentTeam = math.mod(frameCounter, table.getn(teams)*CHECK_EVERY)
  if math.mod(currentTeam, CHECK_EVERY) == 0 then
    currentTeam = currentTeam/CHECK_EVERY
    --Spring.SendCommands({"specteam " .. currentTeam})
    local units = Spring.GetTeamUnits(currentTeam)
    for i,v in ipairs(units) do
      local unitHealth = Spring.GetUnitHealth(v)
      if not unitHealths[v] then
        HealthChange(v, unitHealth)
        unitHealths[v] = unitHealth
      elseif unitHealth ~= unitHealths[v] then
        HealthChange(v, unitHealth - unitHealths[v])
        unitHealths[v] = unitHealth
      end
    end
    CheckMostActiveSector()
  end
  UpdateCamera()
end

--[[
function widget:DrawScreen()
  if inSpecMode then
    drawTable(sectorHealthChanges)
  end
end
]]
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
--  debug functions

function drawTable(theTable, maxDepth, initX, initY, level, knownTables)
  local TEXT_HEIGHT = 9
  local INDENT = 100
  if maxDepth    == nil then maxDepth    = 10  end
  if initX       == nil then initX       = 20  end
  if initY       == nil then initY       = 730 end
  if level       == nil then level       = 1   end
  if knownTables == nil then knownTables = {}  end
  if initY       <= 0   then return        0   end
  local currentY = initY
  for i, v in pairs(knownTables) do
    if v == theTable then
      gl.Text(MagentaStr .. "--> " .. i, initX, currentY, TEXT_HEIGHT, "O")
      return 0
    end
  end
  table.insert(knownTables, theTable)
  --gl.Text(MagentaStr .. table.getn(knownTables), initX-1-INDENT, currentY, TEXT_HEIGHT, "or")
  if level == maxDepth+1 then
    gl.Text(RedStr..tostring(theTable).." (max Depth - getn: "..table.getn(theTable)..")", initX, currentY, TEXT_HEIGHT, "O")
    return 0
  end
  gl.Text(GreenStr .. "__tostring", initX, currentY, TEXT_HEIGHT, "o")
  gl.Text(tostring(theTable), initX+INDENT, currentY, TEXT_HEIGHT, "o")
  currentY = currentY - TEXT_HEIGHT - 1
  for i, v in pairs(theTable) do
    gl.Text(GreenStr .. i, initX, currentY, TEXT_HEIGHT, "o")
    if type(v) == "string" or type(v) == "number" then
      gl.Text(v, initX+INDENT, currentY, TEXT_HEIGHT, "o")
    end
    if type(v) == "boolean" then
      if v then
        gl.Text("true", initX+INDENT, currentY, TEXT_HEIGHT, "o")
      else
        gl.Text("false", initX+INDENT, currentY, TEXT_HEIGHT, "o")
      end
    end
    if type(v) == "table" then
      currentY = currentY - drawTable(v, maxDepth, initX + INDENT, currentY, level+1, knownTables)
    end
    if type(v) == "function" then
      gl.Text(BlackStr .. "function", initX+INDENT, currentY, TEXT_HEIGHT, "O")
    end
    currentY = currentY - TEXT_HEIGHT - 1
  end
  if currentY == initY then
    gl.Text(BlackStr .. "empty table", initX, currentY, TEXT_HEIGHT, "O")
  end
  local metaT = getmetatable(theTable)
  if metaT ~= nil then
    gl.Text(YellowStr .. "metatable", initX, currentY, TEXT_HEIGHT, "o")
    currentY = currentY - drawTable(metaT, maxDepth, initX+INDENT, currentY, level+1, knownTables)
  end
  return initY-currentY
end