import os

from shared.db import get_roster, put_roster
from shared.slack import get_channel_members, get_user_info


def lambda_handler(event, context):
    channel_id = os.environ.get("SLACK_CHANNEL_ID") or __import__(
        "shared.secrets", fromlist=["get_parameter"]
    ).get_parameter(os.environ["SLACK_CHANNEL_PARAM"])

    member_ids = get_channel_members(channel_id)
    if not member_ids:
        return {"status": "error", "message": "No members found in channel"}

    employees = []
    skipped = 0
    for uid in member_ids:
        info = get_user_info(uid)
        if not info or info.get("is_bot") or info.get("id") == "USLACKBOT":
            skipped += 1
            continue

        profile = info.get("profile", {})
        name = profile.get("real_name") or info.get("real_name", "")
        email = profile.get("email", "")

        if not name or not email:
            skipped += 1
            continue

        employees.append(
            {
                "name": name,
                "email": email,
                "slack_user_id": uid,
            }
        )

    employees.sort(key=lambda e: e["name"])

    existing = get_roster()
    existing_set = {(e["name"], e["email"], e["slack_user_id"]) for e in existing}
    new_set = {(e["name"], e["email"], e["slack_user_id"]) for e in employees}

    if existing_set == new_set:
        return {
            "status": "no_change",
            "employee_count": len(employees),
        }

    put_roster(employees)

    added = new_set - existing_set
    removed = existing_set - new_set

    return {
        "status": "synced",
        "employee_count": len(employees),
        "added": len(added),
        "removed": len(removed),
        "skipped": skipped,
    }