1 files changed, 80 insertions, 0 deletions
diff --git a/util/locale_database/iso639_3.py b/util/locale_database/iso639_3.py
new file mode 100644
index 0000000000..0d23065cf9
--- /dev/null
+++ b/util/locale_database/iso639_3.py
@@ -0,0 +1,80 @@
+# Copyright (C) 2021 The Qt Company Ltd.
+# SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0
+
+from dataclasses import dataclass
+from typing import Dict, Optional
+
+
+@dataclass
+class LanguageCodeEntry:
+    part3Code: str
+    part2BCode: Optional[str]
+    part2TCode: Optional[str]
+    part1Code: Optional[str]
+
+    def id(self) -> str:
+        if self.part1Code:
+            return self.part1Code
+        if self.part2BCode:
+            return self.part2BCode
+        return self.part3Code
+
+    def __repr__(self) -> str:
+        parts = [f'{self.__class__.__name__}({self.id()!r}, part3Code={self.part3Code!r}']
+        if self.part2BCode is not None and self.part2BCode != self.part3Code:
+            parts.append(f', part2BCode={self.part2BCode!r}')
+            if self.part2TCode != self.part2BCode:
+                parts.append(f', part2TCode={self.part2TCode!r}')
+        if self.part1Code is not None:
+            parts.append(f', part1Code={self.part1Code!r}')
+        parts.append(')')
+        return ''.join(parts)
+
+
+class LanguageCodeData:
+    """
+    Representation of ISO639-2 language code data.
+    """
+    def __init__(self, fileName: str):
+        """
+        Construct the object populating the data from the given file.
+        """
+        self.__codeMap: Dict[str, LanguageCodeEntry] = {}
+
+        with open(fileName, 'r', encoding='utf-8') as stream:
+            stream.readline() # skip the header
+            for line in stream.readlines():
+                part3Code, part2BCode, part2TCode, part1Code, _ = line.split('\t', 4)
+
+                # sanity checks
+                assert all(p.isascii() for p in (part3Code, part2BCode, part2TCode, part1Code)), \
+                    f'Non-ascii characters in code names: {part3Code!r} {part2BCode!r} '\
+                        f'{part2TCode!r} {part1Code!r}'
+
+                assert len(part3Code) == 3, f'Invalid Part 3 code length for {part3Code!r}'
+                assert not part1Code or len(part1Code) == 2, \
+                    f'Invalid Part 1 code length for {part3Code!r}: {part1Code!r}'
+                assert not part2BCode or len(part2BCode) == 3, \
+                    f'Invalid Part 2B code length for {part3Code!r}: {part2BCode!r}'
+                assert not part2TCode or len(part2TCode) == 3, \
+                    f'Invalid Part 2T code length for {part3Code!r}: {part2TCode!r}'
+
+                assert (part2BCode == '') == (part2TCode == ''), \
+                    f'Only one Part 2 code is specified for {part3Code!r}: ' \
+                    f'{part2BCode!r} vs {part2TCode!r}'
+                assert not part2TCode or part2TCode == part3Code, \
+                    f'Part 3 code {part3Code!r} does not match Part 2T code {part2TCode!r}'
+
+                entry = LanguageCodeEntry(part3Code, part2BCode or None,
+                    part2TCode or None, part1Code or None)
+
+                self.__codeMap[entry.id()] = entry
+
+    def query(self, code: str) -> Optional[LanguageCodeEntry]:
+        """
+        Lookup the entry with the given code and return it.
+
+        The entries can be looked up by using either the Alpha2 code or the bibliographical
+        Alpha3 code.
+        """
+        return self.__codeMap.get(code)