WIP: i18n editor, start apple wallet generation

src/pretix/plugins/wallet/styles/apple.py

@@ -1,25 +1,132 @@
 from .base import (
     FieldEntry,
-    FieldEntryContentType,
+    FieldEntryType,
     FieldContentType,
     ImageFieldGroup,
     PlaceholderFieldGroup,
     TextFieldGroup,
     WalletPlatform,
     PassStyle,
+    PlaceholderFieldEntry,
+    CustomFieldEntry,
 )
 from django.utils.translation import gettext as _
 from i18nfield.strings import LazyI18nString
-
+import io
+import hashlib
+import zipfile
+import cryptography
+import cryptography.hazmat.primitives.serialization.pkcs7
+# from cryptography import x509
+# from cryptography.hazmat.primitives import hashes, serialization
+# from cryptography.hazmat.primitives.serialization import pkcs7
+import json
 
 class ApplePlatform(WalletPlatform):
     identifier = "apple"
     name = _("Apple")
 
 
+class StringResource:
+    # mapping string in default event locale -> LazyI18nString
+    entries: dict[str, LazyI18nString]
+    locales: set[str]
+
+    def __init__(self, locales):
+        self.entries = {}
+        self.locales = set(locales)
+
+    def add_entry(self, key: str, value: LazyI18nString): # TODO: replace LazyI18nString with dict or handle strings where data == ""
+        if key in self.entries:
+            raise ValueError(f"{key} already exists in this StringResource")
+        self.entries[key] = value
+        if isinstance(value.data, dict):
+            self.locales |= value.data.keys()
+
+    def escape(self, string):
+        return string.translate(str.maketrans({"\"": "\\\"", "\r": "\\r", "\n": "\\n", "\\": "\\\\"}))
+    def generate_resource(self, language):
+        output = ""
+        for key, entry in self.entries.items():
+            output += f'"{self.escape(key)}" = "{self.escape(entry.localize(language))}";\n'
+        return output.strip()
+    
+    def generate(self):
+        return {language: self.generate_resource(language) for language in self.locales}
+            
+
+
+class SignedZipFile:
+    """ Generates a zip-file with manifest and signature as apple expects a pkpass file to be """
+    def __init__(self, ca_certificate, certificate, key, password):
+        self.ca_certificate = cryptography.x509.load_pem_x509_certificate(ca_certificate)
+        self.certificate = cryptography.x509.load_pem_x509_certificate(certificate)
+        self.key = cryptography.hazmat.primitives.serialization.load_pem_private_key(key, password)
+        self.password = password
+
+        self.file = io.BytesIO()
+        self.zip_file = zipfile.ZipFile(self.file, "w")
+        self.manifest = {}
+
+    def sign(self, data: bytes):
+        return (
+            cryptography.hazmat.primitives.serialization.pkcs7.PKCS7SignatureBuilder()
+            .set_data(data)
+            .add_signer(
+                self.certificate,
+                self.key,
+                cryptography.hazmat.primitives.hashes.SHA256(),
+            )
+            .add_certificate(self.ca_certificate)
+            .sign(
+                cryptography.hazmat.primitives.serialization.Encoding.DER,
+                [
+                    cryptography.hazmat.primitives.serialization.pkcs7.PKCS7Options.Binary,
+                    cryptography.hazmat.primitives.serialization.pkcs7.PKCS7Options.DetachedSignature,
+                ],
+            )
+        )
+
+    def finish(self):
+        manifest = json.dumps(self.manifest).encode()
+        signature = self.sign(manifest)
+        self.add_file("manifest.json", manifest)
+        self.add_file("signature", signature)
+        self.zip_file.close()
+        return self.file.getvalue()
+
+    def add_file(self, filename: str, content: str | bytes):
+        if isinstance(content, str):
+            content = content.encode()
+
+        with self.zip_file.open(filename, "w") as f:
+            f.write(content)
+        self.manifest[filename] = hashlib.sha1(content).hexdigest()
+
+
 class AppleWalletStyle(PassStyle):
     platform = ApplePlatform
 
+    def generate_pass_json(self, layout, context):
+        pass_json = {}
+        return pass_json
+    
+    def generate(self, layout, context):
+        for key in ["certificate", "key", "wwdr_certificate", "password"]:
+            if key not in context:
+                raise ValueError(f"{key} missing from context")
+        pkpass = SignedZipFile(
+            context["certificate"],
+            context["key"],
+            context["wwdr_certificate"],
+            context["password"],
+        )
+
+        pass_json = self.generate_pass_json()
+        pkpass.add_file("pass.json", json.dumps(pass_json))
+        return pkpass.finish()
+
+
 class AppleWalletEventTicket(AppleWalletStyle):
     identifier = "event_1"
     name = _("Event Ticket Layout 1")
@@ -31,10 +138,8 @@ class AppleWalletEventTicket(AppleWalletStyle):
             max_entries=1,
             labels=False,
             default_entries=[
-                FieldEntry(
-                    type=FieldEntryContentType.IMAGE,
-                    label=LazyI18nString("logo"),
-                    content="event:image",
+                PlaceholderFieldEntry(
+                    content="poweredby",
                 )
             ],
         ),
@@ -44,13 +149,12 @@ class AppleWalletEventTicket(AppleWalletStyle):
             min_entries=1,
             max_entries=1,
             default_entries=[
-                FieldEntry(
-                    type=FieldEntryContentType.PLACEHOLDER,
+                PlaceholderFieldEntry(
                     label=LazyI18nString({"de": "Tickettyp", "en": "Ticket type"}),
                     content="item",
                 )
             ],  # TODO: support Lazyi18nproxy here
-            description=_("These fields appear prominently featured on the pass.")
+            description=_("These fields appear prominently featured on the pass."),
         ),
         TextFieldGroup(
             identifier="secondary", name=_("Secondary"), max_entries=4
@@ -62,5 +166,3 @@ class AppleWalletEventTicket(AppleWalletStyle):
         TextFieldGroup(identifier="back", name=_("Back")),
     ]
     # preview_image = "apple/event_ticket.svg"
-
-