From 890ff5631177433792f29e57ca0a01b5f4bcb84c Mon Sep 17 00:00:00 2001
From: thebigmunch <mail@thebigmunch.me>
Date: Fri, 21 Feb 2020 15:57:56 -0500
Subject: [PATCH] Add support for ID3v2 involved people list frames [#22]

---
 CHANGELOG.md                               |  6 +++
 src/audio_metadata/formats/id3v2.py        |  4 ++
 src/audio_metadata/formats/id3v2_frames.py | 54 ++++++++++++++++++++--
 3 files changed, 60 insertions(+), 4 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index f2db855..945b55e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,12 @@ This project adheres to [Semantic Versioning](https://semver.org).
 
 [Commits](https://github.com/thebigmunch/audio-metadata/compare/0.7.0...master)
 
+### Added
+
+* Support for ID3v2 involved people list frames.
+	* ``ID3v2InvolvedPerson``.
+	* ``ID3v2InvolvedPeopleListFrame``.
+
 ### Changed
 
 * Make all attrs classes require keyword arguments.
diff --git a/src/audio_metadata/formats/id3v2.py b/src/audio_metadata/formats/id3v2.py
index 19bbb9b..85e1b50 100644
--- a/src/audio_metadata/formats/id3v2.py
+++ b/src/audio_metadata/formats/id3v2.py
@@ -70,6 +70,7 @@ class ID3v2Frames(Tags):
 			'originalartist': 'TOA',
 			'originalauthor': 'TOL',
 			'originaldate': 'TOR',
+			'people': 'IPL',
 			'pictures': 'PIC',
 			'playcount': 'CNT',
 			'remixer': 'TP4',
@@ -113,6 +114,7 @@ class ID3v2Frames(Tags):
 			'originalartist': 'TOPE',
 			'originalauthor': 'TOLY',
 			'originaldate': 'TORY',
+			'people': 'IPLS',
 			'pictures': 'APIC',
 			'playcount': 'PCNT',
 			'remixer': 'TPE4',
@@ -158,6 +160,7 @@ class ID3v2Frames(Tags):
 			'originalartist': 'TOPE',
 			'originalauthor': 'TOLY',
 			'originaldate': 'TDOR',
+			'people': 'TIPL',
 			'pictures': 'APIC',
 			'playcount': 'PCNT',
 			'remixer': 'TPE4',
@@ -257,6 +260,7 @@ def load(cls, data, id3_version):
 			elif isinstance(
 				frame,
 				(
+					ID3v2InvolvedPeopleListFrame,
 					ID3v2NumericTextFrame,
 					ID3v2TextFrame,
 					ID3v2TimestampFrame,
diff --git a/src/audio_metadata/formats/id3v2_frames.py b/src/audio_metadata/formats/id3v2_frames.py
index 99d8c3d..1af0a07 100644
--- a/src/audio_metadata/formats/id3v2_frames.py
+++ b/src/audio_metadata/formats/id3v2_frames.py
@@ -6,6 +6,8 @@
 	'ID3v2Frame',
 	'ID3v2GEOBFrame',
 	'ID3v2GenreFrame',
+	'ID3v2InvolvedPeopleListFrame',
+	'ID3v2InvolvedPerson',
 	'ID3v2NumberFrame',
 	'ID3v2NumericTextFrame',
 	'ID3v2Picture',
@@ -26,6 +28,7 @@
 import struct
 from urllib.parse import unquote
 
+import more_itertools
 from attr import (
 	attrib,
 	attrs,
@@ -52,6 +55,15 @@
 _genre_re = re.compile(r"((?:\((?P<id>\d+|RX|CR)\))*)(?P<name>.+)?")
 
 
+@attrs(
+	repr=False,
+	kw_only=True,
+)
+class ID3v2InvolvedPerson(AttrMapping):
+	involvement = attrib()
+	name = attrib()
+
+
 class ID3v2Picture(Picture):
 	@datareader
 	@classmethod
@@ -117,6 +129,14 @@ class ID3v2GEOBFrame(ID3v2BaseFrame):
 	value = attrib()
 
 
+@attrs(
+	repr=False,
+	kw_only=True,
+)
+class ID3v2InvolvedPeopleListFrame(ID3v2BaseFrame):
+	value = attrib()
+
+
 @attrs(
 	repr=False,
 	kw_only=True,
@@ -311,26 +331,29 @@ class ID3v2Frame(ID3v2BaseFrame):
 	value = attrib()
 
 	# TODO:ID3v2.2
-	# TODO: BUF, CNT, CRA, CRM, ETC, EQU, IPL, LNK, MCI, MLL, POP, REV,
+	# TODO: BUF, CNT, CRA, CRM, ETC, EQU, LNK, MCI, MLL, POP, REV,
 	# TODO: RVA, STC, UFI
 
 	# TODO: ID3v2.3
-	# TODO: AENC, COMR, ENCR, EQUA, ETCO, GRID, IPLS, LINK, MCDI, MLLT, OWNE
+	# TODO: AENC, COMR, ENCR, EQUA, ETCO, GRID, LINK, MCDI, MLLT, OWNE
 	# TODO: PCNT, POPM, POSS, RBUF, RVAD, RVRB, SYTC, UFID, USER
 
 	# TODO: ID3v2.4
-	# TODO: ASPI, EQU2, RVA2, SEEK, SIGN, TDEN, TDOR, TDRC, TDRL, TDTG, TIPL
-	# TODO: TMCL, TPRO,
+	# TODO: ASPI, EQU2, RVA2, SEEK, SIGN, TDEN, TDOR, TDRC, TDRL, TDTG
+	# TODO: TMCL, TPRO
 
 	_FRAME_TYPES = {
 		# Complex Text Frames
 		'COM': ID3v2CommentFrame,
 		'GEO': ID3v2GEOBFrame,
+		'IPL': ID3v2InvolvedPeopleListFrame,
 		'TXX': ID3v2UserTextFrame,
 
 		'COMM': ID3v2CommentFrame,
 		'GEOB': ID3v2GEOBFrame,
+		'IPLS': ID3v2InvolvedPeopleListFrame,
 		'PRIV': ID3v2PrivateFrame,
+		'TIPL': ID3v2InvolvedPeopleListFrame,
 		'TXXX': ID3v2UserTextFrame,
 
 		# Genre Frame
@@ -492,6 +515,29 @@ def load(cls, data, struct_pattern, size_len, per_byte):
 			kwargs['language'] = decode_bytestring(frame_data[1:4])
 			kwargs['description'] = decode_bytestring(values[0], encoding)
 			kwargs['value'] = decode_bytestring(values[1], encoding)
+		elif frame_type is ID3v2InvolvedPeopleListFrame:
+			encoding = determine_encoding(frame_data[0:1])
+
+			values = []
+			tail = frame_data[1:]
+
+			while tail:
+				head, tail = split_encoded(tail, encoding)
+				values.append(head)
+
+			people = [
+				ID3v2InvolvedPerson(
+					involvement=decode_bytestring(involvement, encoding),
+					name=decode_bytestring(name, encoding),
+				)
+				for involvement, name in more_itertools.chunked(values, 2)
+			]
+
+			# Ignore empty people list.
+			if len(values) < 1:
+				return None
+
+			kwargs['value'] = people
 		elif frame_type is ID3v2GenreFrame:
 			encoding = determine_encoding(frame_data[0:1])