if event.type == "program" then
  mem.events = {}
  mem.treecount = 0
  mem.inventory = {sapling = 0, fertiliser = 0}
  digiline_send("treedetector",{distance=0, command="get"})
  digiline_send("extender1", {a = false, b = false, c = false, d = false})
  digiline_send("extender2", {a = false, b = false, c = false, d = false})
  mem.state = "idle"
  mem.isSaplingOrdered = false
  mem.isFertiliserOrederd = false
end

if event.type == "digiline" then
  if event.channel == "treesort" then
    local count = mem.inventory[event.msg.name]
    if count == nil then count = 0 end
    mem.inventory[event.msg.name]= count + event.msg.count
  end
  
  if event.channel == "treedetector" then
    mem.currentItem = event.msg
    interrupt(1)
  end
  
  if event.channel == "chainsawindetector" then
    digiline_send("extender1", {a = false, b = false, c = false, d = false})
    mem.state = "prepare"
    interrupt(30)
  end
  
  if event.channel == "drawercontroller" and event.msg.status then
    if event.msg.name == "treefarmingsapplingorder" then
      mem.isSaplingOrdered = false
      if mem.isFertiliserOrederd == false then mem.state = "prepare" interrupt(30) end
    end
    
    if event.msg.name == "treefarmingfertilisedorder" then
      mem.isFertiliserOrederd = false
      if mem.isSaplingOrdered == false then mem.state = "prepare" interrupt(30) end
    end
  end
end

if event.type == "interrupt" then
  if mem.state == "idle" then interrupt(10) end
  
  if mem.state == "wait" then
    local item = mem.currentItem
    if item:find("sapling", 1, true) then
      digiline_send("extender2", {a = false, b = false, c = false, d = false})
      mem.state = "fertilising"
      interrupt(1)
    elseif item:find("trunk", 1, true) or item:find("tree", 1, true) then
      digiline_send("extender2", {a = false, b = false, c = false, d = false})
      digiline_send("extender1", {a = false, b = false, c = false, d = false})
      mem.state = "cut"
      interrupt(1)
    elseif item == "air" then
      digiline_send("extender1", {a = false, b = false, c = false, d = true})
      mem.state = "recharge"
      return
    else
      digiline_send("treedetector",{distance=0, command="get"})
      interrupt(5)
    end
  end
  
  if mem.state == "prepare" then
    local item = mem.currentItem
    if item ~= "air" then mem.state = "wait" interrupt(1) return end
    if mem.inventory["sapling"] == 0 or mem.inventory["fertiliser"] == 0 then
      --order from drawer default:sapling and pandorabox_custom:super_fertiliser
      if mem.inventory["sapling"] == 0 then
        local order = {
          name="treefarmingsapplingorder",
          destination="Tacit:treefarming",
          item="default:sapling",
          stacksize=1, count=1
        }
        digiline_send("drawercontroller", order)
        mem.isSaplingOrdered = true
        mem.state = "pause"
        digiline_send("treemon", "no sapling\nordering...")
      end
      if mem.inventory["fertiliser"] == 0 then
        local order = {
          name="treefarmingfertilisedorder",
          destination="Tacit:treefarming",
          item="pandorabox_custom:super_fertiliser",
          stacksize=99, count=1
        }
        mem.isFertiliserOrederd = true
        digiline_send("drawercontroller", order)
        digiline_send("treemon", "no\nfertiliser\nordering...")
        mem.state = "pause"
      end
    else
      mem.state = "planting"
      digiline_send("extender2", {c=false})
      interrupt(20)
    end
  end
  
  if mem.state == "planting" then
    digiline_send("extender2", {c=true})
    mem.inventory["sapling"] = mem.inventory["sapling"] - 1
    mem.state = "wait"
    mem.currentItem = ""
    interrupt(1)
  end
  
  if mem.state == "fertilising" then
    digiline_send("extender2", {b=true})
    mem.inventory["fertiliser"] = mem.inventory["fertiliser"] - 1
    mem.state = "wait"
    mem.currentItem = ""
    interrupt(1)
  end
  
  if mem.state == "cut" then
    digiline_send("extender1", {c = true})
    mem.state = "wait"
    mem.currentItem = ""
    mem.treecount = mem.treecount + 1
    local str = "Trees done:\n" ..
               tostring(mem.treecount) .. "\n" ..
               "saplings:\n" ..
               tostring(mem.inventory["sapling"]) .. "\n" ..
               "fertiliser\n" ..
               tostring(mem.inventory["fertiliser"])
    digiline_send("treemon", str)
    interrupt(1)
  end
end

if event.type == "on" and event.pin.name == "A" then
  mem.state = "prepare"
  interrupt(1)
end

if event.type == "off" and event.pin.name == "A" then
  mem.state = "idle"
  interrupt(1)
end