From ce33adaa9f75ec81ef4c5bf20ea51d22a040b812 Mon Sep 17 00:00:00 2001
From: Kiritow <1362050620@qq.com>
Date: Thu, 22 Mar 2018 23:37:28 +0800
Subject: [PATCH] Add three way crossing program

---
 crossing3.lua | 152 ++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 152 insertions(+)
 create mode 100644 crossing3.lua

diff --git a/crossing3.lua b/crossing3.lua
new file mode 100644
index 0000000..40f8f1d
--- /dev/null
+++ b/crossing3.lua
@@ -0,0 +1,152 @@
+require("libevent")
+require("util")
+local component=require("component")
+local computer=require("computer")
+
+-- Hardware
+local drecv=proxy("digital_receiver_box")
+local dsend=proxy("digital_controller_box")
+
+local SA=proxy("digital_detector","6")
+local SB=proxy("digital_detector","9")
+local SC=proxy("digital_detector","2")
+
+local nameA="StationA"
+local nameB="StationB"
+local nameC="StationC"
+
+--[[
+    getAspect/setAspect: 1 Green 3 Yellow 5 Red
+    SigIn : LAIN LAOUT LBIN LBOUT LCIN LCOUT 
+    SigOut: KA MA KB MB KC MC
+    Device: SA SB SC
+]]
+
+local green=1
+local yellow=3
+local red=5
+
+local function getSignal(name)
+    return drecv.getAspect(name)
+end
+
+local function setSignal(name,val)
+    dsend.setAspect(name,val)
+end
+
+local function resetSystem()
+    setSignal("KA",red)
+    setSignal("KB",red)
+    setSignal("KC",red)
+    setSignal("MA",red)
+    setSignal("MB",red)
+    setSignal("MC",red)
+end
+
+local function getOperation(trainID,from)
+    return math.random(0,1)
+end
+
+local function main()
+    resetSystem()
+    local bus=CreateEventBus()
+    bus:listen("minecart",function(e)
+        return (string.find(e.minecartType,"locomotive")~=nil)
+    end)
+    bus:listen("interrupted")
+
+    while true do
+        print("Waiting event...")
+        local e=bus:next()
+        if(e.event=="interrupted") then break end
+
+        -- Try to solve
+        local ans=-1
+        if(e.detectorAddress==SA.address) then
+            print("A-->?")
+            ans=getOperation(e.destination,nameA)
+        elseif(e.detectorAddress==SB.address) then
+            print("B-->?")
+            ans=getOperation(e.destination,nameB)
+        elseif(e.detectorAddress==SC.address) then
+            print("C-->?")
+            ans=getOperation(e.destination,nameC)
+        end
+
+        local solved=false
+
+        if(ans==-1) then
+            print("Unknown Train")
+        elseif(ans==0) then
+            if(e.detectorAddress==SA.address) then
+                if(getSignal("LBIN")==green) then
+                    print("A-->B")
+                    setSignal("MA",red)
+                    setSignal("KA",green)
+                    WaitEventEx("aspect_changed",nil,"LBIN")
+                    setSignal("KA",red)
+                    solved=true
+                end
+            elseif(e.detectorAddress==SB.address) then
+                if(getSignal("LAIN")==green) then
+                    print("B-->A")
+                    setSignal("MB",red)
+                    setSignal("KB",green)
+                    WaitEventEx("aspect_changed",nil,"LAIN")
+                    setSignal("KB",red)
+                    solved=true
+                end
+            elseif(e.detectorAddress==SC.address) then
+                if(getSignal("LAIN")==green) then
+                    print("C-->A")
+                    setSignal("MB",red)
+                    setSignal("MC",red)
+                    setSignal("KC",green)
+                    WaitEventEx("aspect_changed",nil,"LAIN")
+                    setSignal("KC",red)
+                    solved=true
+                end
+            end
+        elseif(ans==1) then
+            if(e.detectorAddress==SA.address) then
+                if(getSignal("LCIN")==green) then
+                    print("A-->C")
+                    setSignal("MA",green)
+                    setSignal("KA",green)
+                    WaitEventEx("aspect_changed",nil,"LCIN")
+                    setSignal("KA",red)
+                    solved=true
+                end
+            elseif(e.detectorAddress==SB.address) then
+                if(getSignal("LCIN")==green) then
+                    print("B-->C")
+                    setSignal("MB",green)
+                    setSignal("KB",green)
+                    WaitEventEx("aspect_changed",nil,"LCIN")
+                    setSignal("KB",red)
+                    solved=true
+                end
+            elseif(e.detectorAddress==SC.address) then
+                if(getSignal("LBIN")==green) then
+                    print("C-->B")
+                    setSignal("MC",green)
+                    setSignal("KC",green)
+                    WaitEventEx("aspect_changed",nil,"LBIN")
+                    setSignal("KC",red)
+                    solved=true
+                end
+            end
+        end
+
+        if(not solved) then
+            table.insert(bus.events,e)
+            os.sleep(0.5)
+        end
+    end
+
+    resetSystem()
+end
+
+print("Program Started")
+main()
+print("Program Stopped")
\ No newline at end of file