#!/usr/bin/lua

local function log(message)
        os.execute("logger " .. message)
        print(message)
end

if (table.getn(arg) == 0) then
        print("Usage: ./print-fetch {printerSocket} {gcodeServerURL} {id} [startGcode] [endGCode]")
        return
end

log("starting gcode fetch program")

package.cpath = package.cpath .. '/usr/lib/lua/?.so'
JSON = (loadfile "/usr/share/lua/wifibox/util/JSON.lua")()

local p3d = require("print3d")

local printer = p3d.getPrinter(arg[1])
if printer == nil then
        log("error connecting to printer")
        return
end

local gcodeServer = arg[2]

local finished = false

local id = arg[3]

log("gcode file id: " .. id)
log("gcode server: " .. gcodeServer)

local info = JSON:decode(io.popen("wget -qO - " .. gcodeServer .. "/info/" .. id):read("*a"))

if info == nil then
        log("could not retrieve file info")
        return
end

local current_line = 0
local total_lines = tonumber(info["lines"])
local started = false

log("total lines: " .. total_lines)

local startCode = nil
local endCode = nil

function countlines(file)
        return tonumber(io.popen("wc -l < " .. file):read('*a'))
end

function readGCodeArg(argi)
        local gcodeFile = arg[argi]
        return io.open(gcodeFile):read('*a')
end

if table.getn(arg) >= 5 then
        startCode = readGCodeArg(4)
        endCode = readGCodeArg(5)
end

if startCode ~= nil then
        log("appending start gcode")
        printer:appendGcode(startCode)
end

while(not finished)
do
        local f = io.popen("wget -qO - " .. gcodeServer .. "/fetch/" .. id .. "/" .. current_line)
        local line = f:read()
        while line ~= nil do
                printer:appendGcode(line, total_lines, { seq_number = -1, seq_total = -1, source = id })
                current_line = current_line + 1
                line = f:read()
        end

        if not started then
                started = true
                print("send print start command")
                printer:startPrint()
        end

        if current_line >= total_lines then
                log("finished fetching gcode")
                if endCode ~= nil then
                        log("appending end gcode")
                        printer:appendGcode(endCode, total_lines, { seq_number = -1, seq_total = -1, source = id })
                end
                finished = true
                break
        end


        local accepts_new_gcode = false

        while (not accepts_new_gcode)
        do
                local current,buffer,total,bufferSize,maxBufferSize = printer:getProgress()
                local percentageBufferSize = bufferSize / maxBufferSize

                if percentageBufferSize < 0.8 then
                        print("buffer below 80% capacity, sending new gcode")
                        accepts_new_gcode = true
                else
                        print("buffer above 80% capacity")
                        os.execute("sleep 10")
                end
        end
end