Add cli, top sender calculation functionality

pyproject.toml

@@ -3,13 +3,9 @@ name = "maildirclean"
 version = "0.1.0"
 description = "Add your description here"
 readme = "README.md"
-authors = [
-    { name = "Alex Selimov", email = "alex@alexselimov.com" }
-]
+authors = [{ name = "Alex Selimov", email = "alex@alexselimov.com" }]
 requires-python = ">=3.13"
-dependencies = [
-    "pandas>=2.2.3",
-]
+dependencies = ["pandas>=2.2.3"]
 
 [project.scripts]
 maildirclean = "maildirclean:main"
@@ -19,6 +15,4 @@ requires = ["hatchling"]
 build-backend = "hatchling.build"
 
 [dependency-groups]
-dev = [
-    "pytest>=8.3.5",
-]
+dev = ["pytest>=8.3.5"]

src/maildirclean/__init__.py

@@ -1,2 +1,5 @@
-def main() -> None:
-    print("Hello from maildirclean!")
+from .cli import cli
+
+
+def main() -> int:
+    return cli()

src/maildirclean/cli.py

@@ -0,0 +1,70 @@
+import argparse
+import sys
+from pathlib import Path
+
+from .maildir import parse_maildir
+
+
+def parse_arguments() -> argparse.Namespace:
+    """Parse command line arguments
+
+    Returns: Namespace object corresponding to parsed arguments
+
+    """
+    parser = argparse.ArgumentParser(
+        description="Analyze email metadata from a maildir directory"
+    )
+    parser.add_argument(
+        "maildir", type=str, help="Path to the maildir directory to analyze"
+    )
+    parser.add_argument(
+        "--top",
+        "-t",
+        type=int,
+        default=5,
+        help="Number of top senders to display (default: 5)",
+    )
+    parser.add_argument(
+        "--verbose", "-v", action="store_true", help="Enable verbose output"
+    )
+
+    args = parser.parse_args()
+    return args
+
+
+def cli():
+    args = parse_arguments()
+
+    maildir_path = Path(args.maildir)
+    if not maildir_path.exists() or not maildir_path.is_dir():
+        print(f"Error: {args.maildir} is not a valid directory", file=sys.stderr)
+        return 1
+
+    if args.verbose:
+        print(f"Analyzing emails in {maildir_path}...")
+
+    maildir = parse_maildir(maildir_path)
+    if args.verbose:
+        print(f"Found {len(maildir._df)} emails")
+
+    top_senders = maildir.get_top_n_senders(args.top)
+
+    if not top_senders:
+        print("No senders found in the maildir", file=sys.stderr)
+        return 0
+
+    result = []
+    for i, sender in enumerate(top_senders, 1):
+        names_str = ", ".join(sender.names[:5])  # Limit to first 5 names
+        if len(sender.names) > 5:
+            names_str += f" and {len(sender.names) - 5} more"
+
+        result.append(f"{i}. {sender.email} - Names used: {names_str}")
+
+    output = "\n".join(
+        [f"Top {len(top_senders)} senders in {maildir_path}:", "=" * 40, *result]
+    )
+
+    print(output)
+
+    return 0

src/maildirclean/maildir.py

@@ -1,8 +1,11 @@
 from pathlib import Path
 import pandas as pd
+import re
+
+from .utility import first_match_or_empty, to_datetime_safe
 
 
-METADATA_SCHEMA = sorted(["Path", "From", "Date"])
+METADATA_SCHEMA = sorted(["path", "from", "date"])
 
 
 def make_email_metadata(email_path: str | Path) -> dict[str, str]:
@@ -15,13 +18,17 @@ def make_email_metadata(email_path: str | Path) -> dict[str, str]:
     Returns: Dict containing the required metadata
     """
     key_is_set = {key: False for key in METADATA_SCHEMA}
-    metadata = {"Path": str(email_path)}
-    key_is_set["Path"] = True
+    metadata = {"path": str(email_path)}
+    key_is_set["path"] = True
 
-    with open(email_path, "r") as f:
+    with open(email_path, "rb") as f:
         for line in f:
             try:
-                k, v = [val.strip() for val in line.split(":", maxsplit=1)]
+                k, v = [
+                    val.strip()
+                    for val in line.decode(errors="ignore").split(":", maxsplit=1)
+                ]
+                k = k.lower()
                 if k in METADATA_SCHEMA:
                     metadata[k] = v
                     key_is_set[k] = True
@@ -63,10 +70,17 @@ class MailDir:
     Stores the metadata associated with all local emails.
     """
 
+    name_regex = r"^(.*?)(?=<)"
+    email_regex = r"<?([a-zA-Z0-9_.+-]+@[a-zA-Z0-9-]+\.[a-zA-Z0-9-.]+)>?"
+
     KEYS_AND_FUNCS = {
-        "Name": lambda df: df["From"].map(lambda x: x.split("<")[0].strip('" ')),
-        "Email": lambda df: df["From"].map(lambda x: x.split("<")[1].strip(">")),
-        "Date": lambda df: pd.to_datetime(df["Date"]),
+        "name": lambda df: df["from"].map(
+            lambda x: first_match_or_empty(MailDir.name_regex, x).strip('" ')
+        ),
+        "email": lambda df: df["from"].map(
+            lambda x: first_match_or_empty(MailDir.email_regex, x).strip("")
+        ),
+        "date": lambda df: df["date"].map(lambda x: to_datetime_safe(x)),
     }
 
     def __init__(self, email_metadata: list[dict[str, str]]):
@@ -93,9 +107,9 @@ class MailDir:
 
         senders = [
             TopSender(
-                email, list(self._df.loc[self._df["Email"] == email, "Name"].unique())
+                email, list(self._df.loc[self._df["email"] == email, "name"].unique())
             )
-            for email in self._df["Email"].value_counts().iloc[0:n].index
+            for email in self._df["email"].value_counts().iloc[0:n].index
         ]
 
         return senders

src/maildirclean/utility.py

@@ -0,0 +1,28 @@
+import re
+import pandas as pd
+from datetime import datetime
+
+
+def first_match_or_empty(pattern: str, text: str) -> str:
+    """Get the first match for the provided pattern or "" if empty.
+    This is a wrapper to facilitate usage of the re.search in lambda expressions
+
+    Args:
+        pattern: Pattern to search for
+        text: Text that will be searched
+
+    Returns: First pattern match or ""
+
+    """
+    match = re.search(pattern, text)
+    if match:
+        return match.group(1)
+    else:
+        return ""
+
+
+def to_datetime_safe(datetime_str: str):
+    try:
+        return pd.to_datetime(datetime_str, format="mixed", errors="coerce")
+    except (ValueError, AttributeError):
+        return datetime.now()

tests/fixtures.py

@@ -125,13 +125,13 @@ def sample_email_dir(tmp_dir):
 @pytest.fixture
 def sample_email_metadata():
     return [
-        {"From": "John Doe <john.doe@example.com>", "Date": "2025-01-01"},
-        {"From": "John Doe <john.doe@example.com>", "Date": "2025-01-02"},
-        {"From": "Johnny Doe <john.doe@example.com>", "Date": "2025-01-03"},
-        {"From": "J. Doe <john.doe@example.com>", "Date": "2025-01-04"},
-        {"From": "Jane Smith <jane.smith@example.com>", "Date": "2025-01-05"},
-        {"From": "Jane S. <jane.smith@example.com>", "Date": "2025-01-06"},
-        {"From": "Alex Johnson <alex.johnson@example.com>", "Date": "2025-01-07"},
-        {"From": "Alex J. <alex.johnson@example.com>", "Date": "2025-01-08"},
-        {"From": "Sarah Williams <sarah@example.com>", "Date": "2025-01-09"},
+        {"from": "John Doe <john.doe@example.com>", "date": "2025-01-01"},
+        {"from": "John Doe <john.doe@example.com>", "date": "2025-01-02"},
+        {"from": "Johnny Doe <john.doe@example.com>", "date": "2025-01-03"},
+        {"from": "J. Doe <john.doe@example.com>", "date": "2025-01-04"},
+        {"from": "Jane Smith <jane.smith@example.com>", "date": "2025-01-05"},
+        {"from": "Jane S. <jane.smith@example.com>", "date": "2025-01-06"},
+        {"from": "Alex Johnson <alex.johnson@example.com>", "date": "2025-01-07"},
+        {"from": "Alex J. <alex.johnson@example.com>", "date": "2025-01-08"},
+        {"from": "Sarah Williams <sarah@example.com>", "date": "2025-01-09"},
     ]

tests/test_maildir.py

@@ -8,20 +8,20 @@ def test_email_parsing(test_email):
 
     metadata = make_email_metadata(test_email)
 
-    assert metadata["From"] == '"John Doe" <sender@example.com>'
-    assert metadata["Date"] == "Wed, 16 Apr 2025 12:23:35 -0400"
-    assert metadata["Path"] == str(test_email)
+    assert metadata["from"] == '"John Doe" <sender@example.com>'
+    assert metadata["date"] == "Wed, 16 Apr 2025 12:23:35 -0400"
+    assert metadata["path"] == str(test_email)
 
 
 def test_maildir_creation(test_email):
     maildir = MailDir([make_email_metadata(test_email)])
 
     metadata = maildir._df.iloc[0]
-    assert metadata["From"] == '"John Doe" <sender@example.com>'
-    assert metadata["Name"] == "John Doe"
-    assert metadata["Email"] == "sender@example.com"
-    assert metadata["Date"] == pd.to_datetime("Wed, 16 Apr 2025 12:23:35 -0400")
-    assert metadata["Path"] == str(test_email)
+    assert metadata["from"] == '"John Doe" <sender@example.com>'
+    assert metadata["name"] == "John Doe"
+    assert metadata["email"] == "sender@example.com"
+    assert metadata["date"] == pd.to_datetime("Wed, 16 Apr 2025 12:23:35 -0400")
+    assert metadata["path"] == str(test_email)
 
 
 def test_get_top_n_senders(sample_email_metadata):
@@ -94,9 +94,9 @@ def test_parse_maildir(sample_email_dir):
     maildir = parse_maildir(sample_email_dir)
 
     assert len(maildir._df) == 3
-    assert "test@something.org" in list(maildir._df["Email"])
-    assert "not_a_test@something.org" in list(maildir._df["Email"])
+    assert "test@something.org" in list(maildir._df["email"])
+    assert "not_a_test@something.org" in list(maildir._df["email"])
 
-    assert "Test" in list(maildir._df["Name"])
-    assert "Not a Test" in list(maildir._df["Name"])
-    assert "Test2" in list(maildir._df["Name"])
+    assert "Test" in list(maildir._df["name"])
+    assert "Not a Test" in list(maildir._df["name"])
+    assert "Test2" in list(maildir._df["name"])