feat(user): report on another user's time entries

- Add user_id parameter to fetch_issues_with_spent_time().
- Support numeric ID, login, or full name resolution.
- Reject ambiguous names and unknown users with clear messages.
- Add CLI flags: --user-id, --user-login, --user-name.
- Only allow one user flag at a time.
- Add ResourceNotFoundError handling.
- Update README with usage examples.
- Add tests for user resolution and CLI flags.

Closes #40

redmine_reporter/client.py

@@ -1,8 +1,8 @@
-from typing import Any, Dict, List, Optional, Tuple
+from typing import Any, Dict, List, Optional, Tuple, Union
 
 import requests
 from redminelib import Redmine
-from redminelib.exceptions import AuthError, ForbiddenError
+from redminelib.exceptions import AuthError, ForbiddenError, ResourceNotFoundError
 from redminelib.resources import Issue
 from urllib3.util.retry import Retry
 
@@ -78,6 +78,8 @@ def _format_redmine_error(exc: Exception) -> str:
             "Access denied: your Redmine account does not have permission "
             "to read time entries or issues."
         )
+    if isinstance(exc, ResourceNotFoundError):
+        return "Requested Redmine resource not found: check user/project identifiers."
 
     # requests HTTPError может быть обёрнуто в python-redmine
     original = getattr(exc, "response", None)
@@ -120,22 +122,91 @@ def _fetch_issues_chunked(redmine: Redmine, issue_ids: List[int]) -> List[Issue]
     return all_issues
 
 
+def _resolve_user_id(redmine: Redmine, user_arg: Union[int, str]) -> int:
+    """Преобразует строковый идентификатор пользователя в числовой ID.
+
+    Если аргумент — число, возвращает его как есть.
+    Если строка, пытается найти пользователя по логину или имени.
+    """
+    if isinstance(user_arg, int):
+        return user_arg
+
+    text = str(user_arg).strip()
+    if not text:
+        raise RedmineAPIError("User identifier cannot be empty.")
+
+    # Сначала пробуем интерпретировать как числовой ID
+    if text.isdigit():
+        return int(text)
+
+    # Затем ищем по логину
+    try:
+        users = redmine.user.filter(login=text)
+        if users:
+            return int(users[0].id)
+    except Exception as exc:
+        raise RedmineAPIError(
+            f"Cannot resolve user login '{text}': {_format_redmine_error(exc)}",
+            original=exc,
+        ) from exc
+
+    # Потом по имени
+    try:
+        users = redmine.user.filter(name=text)
+        if len(users) == 1:
+            return int(users[0].id)
+        if len(users) > 1:
+            matches = ", ".join(str(getattr(u, "login", u.id)) for u in users[:5])
+            raise RedmineAPIError(
+                f"Multiple users match '{text}': {matches}. Use --user-id with numeric ID."
+            )
+    except RedmineAPIError:
+        raise
+    except Exception as exc:
+        raise RedmineAPIError(
+            f"Cannot resolve user name '{text}': {_format_redmine_error(exc)}",
+            original=exc,
+        ) from exc
+
+    raise RedmineAPIError(
+        f"User '{text}' not found. Check the login/name or use --user-id with numeric Redmine ID."
+    )
+
+
+def _get_current_user_id(redmine: Redmine) -> int:
+    """Возвращает ID текущего пользователя."""
+    try:
+        current_user = redmine.user.get("current")
+        return int(current_user.id)
+    except Exception as exc:
+        raise RedmineAPIError(_format_redmine_error(exc), original=exc) from exc
+
+
 def fetch_issues_with_spent_time(
-    from_date: str, to_date: str
+    from_date: str,
+    to_date: str,
+    user_id: Optional[Union[int, str]] = None,
 ) -> Optional[List[Tuple[Issue, float]]]:
     """
-    Fetch unique issues linked to time entries of the current user in given date range,
+    Fetch unique issues linked to time entries of the given user in date range,
     along with total spent hours per issue.
+    If user_id is None, uses current user.
     Returns list of (issue, total_hours) tuples.
     Raises RedmineAPIError on API/auth/network failures.
     """
 
     try:
         redmine = _create_redmine()
-        current_user = redmine.user.get("current")
-        time_entries = redmine.time_entry.filter(
-            user_id=current_user.id, from_date=from_date, to_date=to_date
+        target_user_id = (
+            _resolve_user_id(redmine, user_id)
+            if user_id is not None
+            else _get_current_user_id(redmine)
         )
+        time_entries = redmine.time_entry.filter(
+            user_id=target_user_id, from_date=from_date, to_date=to_date
+        )
+    except RedmineAPIError:
+        raise
     except Exception as exc:
         raise RedmineAPIError(_format_redmine_error(exc), original=exc) from exc