-- Configurable constants
local CHANNEL = 55555
local TOKEN = "LxdIjZPDLL2oZoayb7uR2Lbz7bnnbkxz"
local PROMPT = "MineHost"
 
-- Constants
local HOST = "HOST"
local LEADER = "LEAD"
local FOLLOWER = "FOLLOW"
local LOG = "LOG"
local REQUEST = "REQ"
local LUA_PREFIX = "?"
-- Constant actions
local MOVEBY = "moveby"
local MOVETO = "moveto"
local STATUS = "status"
local POSITION = "position"
local HEADING = "heading"
local QUARRY = "quarry"
-- Constant log
local LOG = "LOG"
local REQUEST = "REQ"
-- Constant requests
local BLOCKED = "blocked"
local ITEM = "item"
local FAILED = "failed"
 
running = true
local modem = peripheral.find("modem")


print("Checking for modem.")
if (modem == nil) then
    error("Modem not found.")
end

print("Modem found. Opening on channel: " .. CHANNEL)
modem.open(CHANNEL)

local function captureString(str, seq)
    if seq == nil then seq = "([^%s]+)" end
    res = {}
    for i in string.gmatch(str, seq) do
        table.insert(res, i)
    end
    return res
end
 
local function printPrompt()
    write(PROMPT .. "> ")
end

local function sendDirective(unit, directive)
    print("Sending directive \"" .. directive .. "\" to " .. unit .. ".")
    modem.transmit(CHANNEL, CHANNEL, TOKEN .. ":" .. unit .. ":" .. HOST .. ":" .. REQUEST ..  ":" .. directive)
end

local function interpretData(data)
    res = captureString(data, "([^%\][^%:]+)")
    if res ~= nil then
        res[5] = table.concat(res, ":", 5)
        return res[1], res[2], res[3], res[4], res[5]
    end
    return nil
end

-- User command loop
print("Now listening for user input.")
local function listenForCommands()
    while running do
        printPrompt()
        local input = read()
        if string.find(input, MOVEBY) == 1 then
            coordsRaw = string.sub(input, string.len(MOVEBY) + 1 + 1)
            local coords = captureString(coordsRaw, "([+-]?%d+)")
            sendDirective(LEADER, MOVEBY .. ":" .. coords[1] .. "," .. coords[2] .. "," .. coords[3])
        elseif string.find(input, MOVETO) == 1 then
            coordsRaw = string.sub(input, string.len(MOVETO) + 1 + 1)
            local coords = captureString(coordsRaw, "([+-]?%d+)")
            sendDirective(LEADER, MOVETO .. ":" .. coords[1] .. "," .. coords[2] .. "," .. coords[3])
        elseif string.find(input, STATUS) == 1 then
            sendDirective(LEADER, STATUS)
        elseif string.find(input, POSITION) == 1 then
            sendDirective(LEADER, POSITION)
        elseif string.find(input, HEADING) == 1 then
            sendDirective(LEADER, HEADING)
        elseif string.find(input, QUARRY) == 1 then
            sendDirective(LEADER, input)
        end
    end
end


-- Status and requests from turtles

local function handleRequest(unit, request)
end

local function handleMessage(unit, str, type)

	if type == LOG then
		local log = string.sub(str, string.len(LOG) + 1 + 1)
		print("[" .. unit .. "]: " .. str)
	elseif type == REQUEST then
		local request = string.sub(str, string.len(REQUEST) + 1 + 1)
        handleRequest(unit, request)
	end
end
		
		
 
local function listenToMiners()
    print("Listening to miners.")
    while running do
		local event, side, sendChannel, replyChannel, data, distance = os.pullEvent("modem_message")
        print("")
        local token, recipient, sender, type, content = interpretData(data)
        if token == TOKEN and recipient == HOST then
            handleMessage(sender, content, type)
        else
            print("Invalid header information. Ignoring.")
        end
        printPrompt()
    end
    print("No longer listening to miners.")
end

parallel.waitForAll(listenToMiners, listenForCommands)