From ed90379c60552de4b8efc3149b89227d66ba8320 Mon Sep 17 00:00:00 2001
From: blunty666 <matthewwblunt@gmail.com>
Date: Sun, 16 Jun 2019 15:14:40 +0100
Subject: [PATCH] Add Plethora scanner strategy

---
 .../plethoraScannerStrategy.lua               | 66 +++++++++++++++++++
 1 file changed, 66 insertions(+)
 create mode 100644 netNav/scanStrategies/plethoraScannerStrategy.lua

diff --git a/netNav/scanStrategies/plethoraScannerStrategy.lua b/netNav/scanStrategies/plethoraScannerStrategy.lua
new file mode 100644
index 0000000..90bafc9
--- /dev/null
+++ b/netNav/scanStrategies/plethoraScannerStrategy.lua
@@ -0,0 +1,66 @@
+local PLETHORA_SCANNER = "plethora:scanner"
+local AIR_BLOCK = "minecraft:air"
+
+function new()
+  return {
+    priority = 10,
+    isAvailable = function()
+      return peripheral.find(PLETHORA_SCANNER)
+    end,
+    execute = function(currentPosition, updateSessionMap, updateServerMap)
+      local scanner = peripheral.find(PLETHORA_SCANNER)
+      if not scanner then return end -- throw error?
+
+      -- get block data from scan and add to temporary map
+      local rawBlockInfo = scanner.scan()
+      local sortedBlockInfo = aStar.newMap()
+      for _, blockInfo in ipairs(rawBlockInfo) do
+        sortedBlockInfo:set(currentPosition + vector.new(blockInfo.x, blockInfo.y, blockInfo.z), blockInfo)
+      end
+
+      -- add adjacent blocks to initial toCheck queue
+      local toCheckQueue = {}
+      for _, pos in ipairs(aStar.adjacent(currentPosition)) do
+		  local blockInfo = sortedBlockInfo:get(pos)
+        if blockInfo then
+          table.insert(toCheckQueue, pos)
+		      blockInfo.queued = true
+        end
+      end
+	  
+      -- flag position of turtle as checked to prevent updating map incorrectly
+      updateSessionMap(currentPosition, false)
+      updateServerMap(currentPosition, false)
+      sortedBlockInfo:get(currentPosition).queued = true
+
+      -- process all blocks from the scan
+      while toCheckQueue[1] do
+        local pos = table.remove(toCheckQueue, 1)
+        local blockInfo = sortedBlockInfo:get(pos)
+        if blockInfo.name == AIR_BLOCK then
+          for _, pos2 in ipairs(aStar.adjacent(pos)) do
+            local blockInfo2 = sortedBlockInfo:get(pos2)
+            if blockInfo2 and not blockInfo2.queued then
+              -- only add air blocks to the toCheck queue to prevent overscanning the area and bloating the map data size
+              table.insert(toCheckQueue, pos2)
+              blockInfo2.queued = true
+            end
+          end
+          updateSessionMap(pos, false)
+          updateServerMap(pos, false)
+        else
+          updateSessionMap(pos, true)
+          updateServerMap(pos, true)
+        end
+      end
+
+      -- go through list again and add all block data to session map
+      for _, blockInfo in ipairs(rawBlockInfo) do
+        local pos = currentPosition + vector.new(blockInfo.x, blockInfo.y, blockInfo.z)
+        if not blockInfo.queued then
+          updateSessionMap(pos, blockInfo.name ~= AIR_BLOCK)
+        end
+      end
+    end,
+  }
+end