Added multi-track tape player

tape-playlist.lua

@@ -0,0 +1,88 @@
+local drive = peripheral.find("tape_drive")
+if not tape then
+    printError("no tape drive found")
+    printError("it's kinda required to play tapes, you know?")
+    return
+end
+
+local running = true
+
+local table_of_contents = {}
+
+local function read32()
+    local v = 0
+    for i = 1, 4 do
+        local b = drive.read()
+        v = bit32.bor(bit32.lshift(v), b)
+    end
+    return v
+end
+
+local function readstr(len)
+    local out = ""
+    for i = 1, len do
+        out = out .. drive.read()
+    end
+    return out
+end
+
+local function bytes2time(b)
+    local s = math.floor(b / 6000)
+    if s < 60 then return string.format("%ds", s) end
+    return string.format("%dm, %ds", math.floor(s / 60), s % 60)
+end
+
+
+parallel.waitForAll(
+function()
+    while running do
+        for i, track in ipairs(table_of_contents) do
+            term.setCursorPos(1, i)
+            term.write(string.format("%s (%s)", track.title, bytes2time(track.length)))
+        end
+        os.sleep(0.1)
+    end
+end,
+function()
+    while running do
+        local evd = { os.pullEvent() }
+        local ev, evd = table.remove(evd, 1), evd
+
+        if ev == "mouse_click" then
+            local x, y = table.unpack(evd, 1)
+        elseif ev == "tape_present" then
+            table_of_contents = {}
+            if evd[1] then
+                drive.seek(-drive.getSize())
+                for i = 1, 48 do
+                    local offset = read32()
+                    local length = read32()
+                    local title = readstr(117)
+                    table.insert(table_of_contents, {
+                        title = title,
+                        offset = offset,
+                        length = length,
+                        ending = offset + length
+                    })
+                end
+            end
+        end
+    end
+end,
+function()
+    local tape_was_present = nil
+    local drive_old_state = nil
+    while running do
+        local tape_present = drive.isReady()
+        if tape_present ~= tape_was_present then
+            os.queueEvent("tape_present", tape_present)
+        end
+
+        local drive_state = drive.getState()
+        if drive_old_state ~= drive_state then
+            os.queueEvent("drive_state", drive_state)
+        end
+
+        os.sleep(0.25)
+    end
+end)

tape-playlist.py

@@ -0,0 +1,73 @@
+#!/usr/bin/env python3
+# x-run: python3 % /mnt/windows/Users/user/Music/vgm/night-in-the-woods/2014-lost-constellation /tmp/lost-constellation.dfpwm
+
+from tempfile import TemporaryDirectory
+from subprocess import Popen, PIPE
+from sys import argv
+from pathlib import Path
+from os.path import splitext
+from math import ceil
+
+DFPWM_ENCODER_EXECUTABLE = "aucmp"
+FFMPEG_EXECUTABLE = "ffmpeg"
+
+DFPWM_SAMPLE_RATE = 6000
+
+TAPE_SIZES = [ 2, 4, 8, 16, 32, 64, 128 ]
+
+input_folder = Path(argv[1])
+output_file = Path(argv[2])
+
+with TemporaryDirectory(prefix="tapedrive") as tmpdir_str:
+    tmpdir = Path(tmpdir_str)
+
+    filelist: list[Path] = []
+    for i, name in enumerate(input_folder.rglob("*.mp3")):
+        if i >= 48:
+            print(f"more than 48 tracks, skipping {name}")
+            continue
+        encoded_file = tmpdir / (splitext(name.name)[0] + ".dfpwm")
+        filelist.append(encoded_file)
+        with encoded_file.open("wb") as fout:
+            with Popen([ DFPWM_ENCODER_EXECUTABLE ], stdout=fout, stdin=PIPE) as dfpwm:
+                with Popen([ FFMPEG_EXECUTABLE, "-i", name, "-f", "s8", "-ac", "1",
+                            "-ar", "48k", "-" ], stdout=dfpwm.stdin) as ffmpeg:
+                    ffmpeg.wait()
+
+    offset: int = 6000
+    titles: list[bytes] = []
+    positions: list[tuple[int, int]] = []
+    for file in filelist:
+        titles.append(file.name.removesuffix(".dfpwm").encode("ascii", errors="replace"))
+        size = ceil(file.stat().st_size / DFPWM_SAMPLE_RATE) * DFPWM_SAMPLE_RATE
+        positions.append((offset, size))
+        offset += size
+
+    with output_file.open("wb") as fout:
+        print("Writing header...")
+        written_bytes: int = 0
+        for i in range(48):
+            name = (titles[i] if i < len(titles) else b"")[:117]
+            pos = positions[i] if i < len(titles) else (0, 0)
+            written_bytes += fout.write(pos[0].to_bytes(4, "little"))
+            written_bytes += fout.write(pos[0].to_bytes(4, "little"))
+            written_bytes += fout.write(name)
+            written_bytes += fout.write(b"\x00" * (117 - len(name)))
+        if written_bytes != 6000:
+            print(f"!!! expected 6000 bytes to be written in header, but it's {written_bytes}")
+
+        print("Writing files...")
+        for i, (pos, file) in enumerate(zip(positions, filelist)):
+            print(f"Writing {file.name}")
+            if written_bytes != pos[0]:
+                print(f"!!! expected to be at {pos[0]}, rn at {written_bytes}")
+            with file.open("rb") as fin:
+                file_size: int = 0
+                while (chunk := fin.read(DFPWM_SAMPLE_RATE)):
+                    file_size += fout.write(chunk)
+                written_bytes += file_size
+                padding_size = DFPWM_SAMPLE_RATE - (written_bytes % DFPWM_SAMPLE_RATE)
+                written_bytes += fout.write(b"\x00" * padding_size)
+        print("Use any of those tapes to store properly:")
+        for size in filter(lambda sz: sz * DFPWM_SAMPLE_RATE * 60 >= written_bytes, TAPE_SIZES):
+            print(f"{size} minutes ({size * DFPWM_SAMPLE_RATE * 60} bytes, {written_bytes * 100 / (size * DFPWM_SAMPLE_RATE * 60):7.3f}% used)")