1 files changed, 122 insertions, 0 deletions
diff --git a/src/debputy/lsp/text_util.py b/src/debputy/lsp/text_util.py
new file mode 100644
index 0000000..d66cb28
--- /dev/null
+++ b/src/debputy/lsp/text_util.py
@@ -0,0 +1,122 @@
+from typing import List, Optional, Sequence, Union, Iterable
+
+from lsprotocol.types import (
+    TextEdit,
+    Position,
+    Range,
+    WillSaveTextDocumentParams,
+)
+
+from debputy.linting.lint_util import LinterPositionCodec
+
+try:
+    from debian._deb822_repro.locatable import Position as TEPosition, Range as TERange
+except ImportError:
+    pass
+
+try:
+    from pygls.workspace import LanguageServer, TextDocument, PositionCodec
+
+    LintCapablePositionCodec = Union[LinterPositionCodec, PositionCodec]
+except ImportError:
+    LintCapablePositionCodec = LinterPositionCodec
+
+
+try:
+    from Levenshtein import distance
+except ImportError:
+
+    def detect_possible_typo(
+        provided_value: str,
+        known_values: Iterable[str],
+    ) -> Sequence[str]:
+        return tuple()
+
+else:
+
+    def detect_possible_typo(
+        provided_value: str,
+        known_values: Iterable[str],
+    ) -> Sequence[str]:
+        k_len = len(provided_value)
+        candidates = []
+        for known_value in known_values:
+            if abs(k_len - len(known_value)) > 2:
+                continue
+            d = distance(provided_value, known_value)
+            if d > 2:
+                continue
+            candidates.append(known_value)
+        return candidates
+
+
+def normalize_dctrl_field_name(f: str) -> str:
+    if not f or not f.startswith(("x", "X")):
+        return f
+    i = 0
+    for i in range(1, len(f)):
+        if f[i] == "-":
+            i += 1
+            break
+        if f[i] not in ("b", "B", "s", "S", "c", "C"):
+            return f
+    assert i > 0
+    return f[i:]
+
+
+def on_save_trim_end_of_line_whitespace(
+    ls: "LanguageServer",
+    params: WillSaveTextDocumentParams,
+) -> Optional[Sequence[TextEdit]]:
+    doc = ls.workspace.get_text_document(params.text_document.uri)
+    return trim_end_of_line_whitespace(doc, doc.lines)
+
+
+def trim_end_of_line_whitespace(
+    doc: "TextDocument",
+    lines: List[str],
+) -> Optional[Sequence[TextEdit]]:
+    edits = []
+    for line_no, orig_line in enumerate(lines):
+        orig_len = len(orig_line)
+        if orig_line.endswith("\n"):
+            orig_len -= 1
+        stripped_len = len(orig_line.rstrip())
+        if stripped_len == orig_len:
+            continue
+
+        edit_range = doc.position_codec.range_to_client_units(
+            lines,
+            Range(
+                Position(
+                    line_no,
+                    stripped_len,
+                ),
+                Position(
+                    line_no,
+                    orig_len,
+                ),
+            ),
+        )
+        edits.append(
+            TextEdit(
+                edit_range,
+                "",
+            )
+        )
+
+    return edits
+
+
+def te_position_to_lsp(te_position: "TEPosition") -> Position:
+    return Position(
+        te_position.line_position,
+        te_position.cursor_position,
+    )
+
+
+def te_range_to_lsp(te_range: "TERange") -> Range:
+    return Range(
+        te_position_to_lsp(te_range.start_pos),
+        te_position_to_lsp(te_range.end_pos),
+    )