local component = require("component")
local term = require("term")
local gpu = component.gpu
local computer = require("computer")
local tape = component.proxy("tape_drive")

COLMAP = {}
local i
for i=0,15 do
    local w = i*255/15
    COLMAP[i] = (w<<16)|(w<<8)|w
    gpu.setPaletteColor(i, COLMAP[i])
end
for i=0,240-1 do
    local r = i%6
    local g = (i//6)%8
    local b = (i//(6*8))

    r = (r*255+2)//5
    g = (g*255+3)//7
    b = (b*255+2)//4

    COLMAP[i+16] = (r<<16)|(g<<8)|b
end

if tape and tape.isReady() then
    tape.stop()
    while tape.seek(-tape.getSize()) ~= 0 do
        os.sleep(0.05)
        tape.stop()
    end
    tape.stop()
end

local fname = ...
local fp = io.open(fname, "rb")

local W = fp:read(1):byte()
local H = fp:read(1):byte()
gpu.setResolution(W, H)
gpu.setBackground(0x000000)
gpu.setForeground(0xFFFFFF)
term.clear()

if sysnative then
    tlast = os.clock()
else
    os.sleep(0.05)
    if tape and tape.isReady() then
        tape.play()
        os.sleep(1.0) -- deal to sound latency
    end
    tlast = computer.uptime()
end

local delay_acc = 0.0
local function delay(d)
    assert(d >= 0.0)
    delay_acc = delay_acc + d
    local dquo = math.floor(delay_acc / 0.05) * 0.05
    delay_acc = delay_acc - dquo
    os.sleep(dquo)
end

while true do
    local s = fp:read(1)
    if s == "" or s == nil then
        break
    end
    local c = s:byte()

    if c == 0xFF then
        tnow = computer.uptime()
        tlast = tlast + 0.05
        while tnow < tlast do
            --delay(tlast-tnow)
            os.sleep(tlast-tnow)
            tnow = computer.uptime()
        end
    elseif c == 0x00 then
        local col = COLMAP[fp:read(1):byte()]
        gpu.setBackground(col)
    else
        local by = fp:read(1):byte()
        local bx = fp:read(1):byte()
        local bw = fp:read(1):byte()
        local bh = c & 0x3F
        local type = c & 0x40
        if type == 0x40 then
            gpu.fill(bx, by, bw, bh, " ")
        else
            if bh < bw then
                for i = 0, bh-1 do
                    gpu.set(bx, by + i, string.rep(" ", bw), false)
                end
            else
                for i = 0, bw - 1 do
                    gpu.set(bx + i, by, string.rep(" ", bh), true)
                end
            end
        end
    end
end

gpu.setBackground(0x000000)
gpu.setForeground(0xFFFFFF)