import subprocess
from datetime import datetime, timedelta

# Run git log command
log_output = subprocess.check_output(
    ['git', 'log', '--pretty=format:%h %an %ad', '--date=iso'],
    text=True
)

# Parse commit dates
commit_times = []
for line in log_output.splitlines():
    parts = line.strip().split()
    if len(parts) < 4:
        continue
    # Commit hash, author, datetime string
    dt_str = " ".join(parts[2:4])  # "YYYY-MM-DD HH:MM:SS"
    try:
        dt = datetime.strptime(dt_str, "%Y-%m-%d %H:%M:%S")
        commit_times.append(dt)
    except ValueError:
        continue

# Sort commits chronologically
commit_times.sort()

# Session grouping (commits < 1 hour apart are same session)
SESSION_GAP = timedelta(hours=1)
sessions = []
if commit_times:
    start = commit_times[0]
    prev = commit_times[0]

    for t in commit_times[1:]:
        if t - prev > SESSION_GAP:
            # Close previous session
            sessions.append((start, prev))
            start = t
        prev = t
    sessions.append((start, prev))  # last session

# Estimate durations
total_time = timedelta()
for start, end in sessions:
    duration = end - start
    # Add a minimum session length (e.g. 30 min) so single commits aren’t near-zero
    if duration < timedelta(minutes=30):
        duration = timedelta(minutes=30)
    total_time += duration

print(f"Number of commits: {len(commit_times)}")
print(f"Number of sessions: {len(sessions)}")
print(f"Estimated total coding time: {total_time} (~{total_time.total_seconds()/3600:.1f} hours)")