"""Encode tagged MP3s, assemble the complete album, and build the local player.""" from pathlib import Path from concurrent.futures import ThreadPoolExecutor from html import escape import hashlib, json, subprocess, sys from build import run ROOT=Path(__file__).resolve().parent.parent NAME='the-distance-turns-to-light' TITLE='The Distance Turns to Light' def fmt(s): s=round(s);return f'{s//60}:{s%60:02d}' def sha(path): h=hashlib.sha256() with path.open('rb') as f: for b in iter(lambda:f.read(1024*1024),b''):h.update(b) return h.hexdigest() def encode(s): stem=s['stem'];dest=ROOT/'mp3'/f'{stem}.mp3' run(['ffmpeg','-hide_banner','-loglevel','error','-y','-i',ROOT/'wav'/f'{stem}.wav','-i',ROOT/'art'/'cover.png', '-map','0:a:0','-map','1:v:0','-c:a','libmp3lame','-b:a','320k','-c:v','png','-disposition:v','attached_pic','-id3v2_version','3', '-metadata',f'title={s["title"]}','-metadata','artist=Cairn','-metadata',f'album={TITLE}','-metadata',f'track={s["number"]}/8', '-metadata','date=2026','-metadata','genre=Trance','-metadata',f'TBPM={s["bpm"]}', '-metadata','comment=Original compositions and code-built instruments. Local edition.',dest]) print('Encoded:',s['title'],flush=True) def player(tracks,total): cards=[] for t in tracks: cards.append(f'') data=json.dumps([dict(title=t['title'],file=t['mp3']) for t in tracks]).replace(' The Distance Turns to Light - Cairn
A striped rising sun above three colored paths in a midnight sky

A night in eight transmissions. Original melodies, custom-built synths, and the long way back to daylight.

CAIRN / LOCAL EDITION

The Distance
Turns to Light

8 tracks · '''+fmt(total)+''' · 132-142 BPM
Original trance in a 1998-2002-inspired sound world.

Select a transmission.
'''+''.join(cards)+'''
''' # Keep the player fully portable in the listening ZIP, without duplicating # the entire album as both individual files and a second, combined MP3. html=html.replace(f'href="{NAME}-full-album.mp3" download>Download complete album',f'id="download" href="{tracks[0]["mp3"]}" download>Download selected track') html=html.replace('audio.src=tracks[n].file;',"audio.src=tracks[n].file;document.getElementById('download').href=tracks[n].file;") return html def main(): scores=json.loads((ROOT/'scores'/'manifest.json').read_text());tracks=[] for s in scores: check=json.loads((ROOT/'checks'/f'{s["stem"]}.json').read_text()) fingerprint=hashlib.sha256((ROOT/'scores'/f'{s["stem"]}.tsv').read_bytes()+(ROOT/'source'/'engine.cpp').read_bytes()).hexdigest() assert check['renderFingerprint']==fingerprint,'Master is stale: '+s['title'] tracks.append(dict(number=s['number'],title=s['title'],stem=s['stem'],seconds=check['seconds'],bpm=s['bpm'],key=s['key'],sections=s['sections'],description=s['description'],mp3=f'mp3/{s["stem"]}.mp3',wav=f'wav/{s["stem"]}.wav',midi=f'midi/{s["stem"]}.mid')) with ThreadPoolExecutor(max_workers=2) as pool:list(pool.map(encode,scores)) total=sum(t['seconds'] for t in tracks) concat=ROOT/'work'/'concat-wav.txt';concat.write_text(''.join(f"file '../wav/{t['stem']}.wav'\n" for t in tracks)) chapters=[';FFMETADATA1'];cursor=0 for t in tracks: chapters+=['[CHAPTER]','TIMEBASE=1/1000',f'START={round(cursor*1000)}',f'END={round((cursor+t["seconds"])*1000)}','title='+t['title']];cursor+=t['seconds'] cp=ROOT/'work'/'chapters.ffmeta';cp.write_text('\n'.join(chapters)+'\n') full=ROOT/f'{NAME}-full-album.mp3' print('Assembling the complete album...',flush=True) run(['ffmpeg','-hide_banner','-loglevel','error','-y','-f','concat','-safe','0','-i',concat,'-i',ROOT/'art'/'cover.png','-i',cp, '-map','0:a:0','-map','1:v:0','-map_chapters','2','-c:a','libmp3lame','-b:a','320k','-c:v','png','-disposition:v','attached_pic','-id3v2_version','3', '-metadata',f'title={TITLE} - Complete Album','-metadata','artist=Cairn','-metadata',f'album={TITLE}','-metadata','date=2026','-metadata','genre=Trance',full]) for t in tracks:t['sha256']={fmt:sha(ROOT/t[fmt]) for fmt in ['mp3','wav','midi']} album=dict(title=TITLE,artist='Cairn',date='2026-09-13',genre='Trance',brief='Original trance inspired by the 1998-2002 era',totalSeconds=total,displayDuration=fmt(total),tracks=tracks,completeAlbum=full.name,completeAlbumSha256=sha(full),masterFormat='44.1 kHz / 24-bit PCM stereo',mp3Format='320 kb/s stereo',localOnly=True) (ROOT/'album.json').write_text(json.dumps(album,indent=2)+'\n') (ROOT/'album.m3u8').write_text('#EXTM3U\n'+''.join(f'#EXTINF:{t["seconds"]:.3f},Cairn - {t["title"]}\n{t["mp3"]}\n' for t in tracks)) (ROOT/'tracklist.txt').write_text(TITLE+' - Cairn\n\n'+''.join(f'{t["number"]:02d} {fmt(t["seconds"])} {t["title"]} / {t["bpm"]} BPM / {t["key"]}\n' for t in tracks)+f'\nTotal: {fmt(total)}\n') (ROOT/'index.html').write_text(player(tracks,total)) (ROOT/'checks'/'sha256.txt').write_text(''.join(f'{t["sha256"][kind]} {t[kind]}\n' for t in tracks for kind in ['mp3','wav','midi'])+f'{album["completeAlbumSha256"]} {full.name}\n') print(json.dumps(dict(album=TITLE,total=fmt(total),tracks=len(tracks),completeAlbum=str(full))),flush=True) if __name__=='__main__': if '--player-only' in sys.argv: album=json.loads((ROOT/'album.json').read_text()) (ROOT/'index.html').write_text(player(album['tracks'],album['totalSeconds'])) else:main()