#!/usr/bin/env python3
"""CLI for managing food items in MongoDB lists.food_items."""

import argparse
import json
import sys
from datetime import datetime, timezone
from pymongo import MongoClient

CONN = "mongodb://root:3wwfoUjyk2E2zWELXFlLuHqfw1ALlOp4pb2H5Vq3TImbMIHL2h1u8Jej2mjzCPl@docdb.connorrhodes.com:35563/?tls=true&tlsAllowInvalidCertificates=true"

def get_collection():
    client = MongoClient(CONN)
    return client["lists"]["food_items"], client

def cmd_add(args):
    coll, client = get_collection()
    doc = {"name": args.name}

    if args.type:
        doc["type"] = args.type
    if args.serving:
        doc["serving"] = args.serving
    if args.description:
        doc["description"] = args.description
    if args.max_dosage:
        doc["max_dosage"] = args.max_dosage
    if args.nutrition:
        try:
            doc["nutrition"] = json.loads(args.nutrition)
        except json.JSONDecodeError:
            print(f"Error: --nutrition must be valid JSON. Got: {args.nutrition}", file=sys.stderr)
            sys.exit(1)
    if args.aliases:
        doc["aliases"] = [a.strip() for a in args.aliases.split(",") if a.strip()]
    if args.extra:
        try:
            extra = json.loads(args.extra)
            doc.update(extra)
        except json.JSONDecodeError:
            print(f"Error: --extra must be valid JSON. Got: {args.extra}", file=sys.stderr)
            sys.exit(1)

    result = coll.insert_one(doc)
    out = coll.find_one({"_id": result.inserted_id})
    out["_id"] = str(out["_id"])
    print(json.dumps(out, indent=2, default=str))
    client.close()

def cmd_get(args):
    coll, client = get_collection()
    query = {}
    if args.name:
        query["$or"] = [
            {"name": {"$regex": args.name, "$options": "i"}},
            {"aliases": {"$regex": args.name, "$options": "i"}},
        ]
    if args.type:
        query["type"] = {"$regex": args.type, "$options": "i"}

    cursor = coll.find(query).sort("name", 1).limit(args.limit if args.limit else 50)
    docs = []
    for d in cursor:
        d["_id"] = str(d["_id"])
        docs.append(d)

    if not docs:
        print("No items found.")
    else:
        print(json.dumps(docs, indent=2, default=str))
    client.close()

def cmd_update(args):
    coll, client = get_collection()

    # Build filter
    if args.id:
        from bson import ObjectId
        query = {"_id": ObjectId(args.id)}
    elif args.name:
        query = {"name": args.name}
    else:
        print("Error: provide --id or --name to identify the item", file=sys.stderr)
        sys.exit(1)

    # Build update
    update_fields = {}
    if args.set_name:
        update_fields["name"] = args.set_name
    if args.set_type:
        update_fields["type"] = args.set_type
    if args.set_serving:
        update_fields["serving"] = args.set_serving
    if args.set_description:
        update_fields["description"] = args.set_description
    if args.set_max_dosage:
        update_fields["max_dosage"] = args.set_max_dosage
    if args.set_aliases:
        update_fields["aliases"] = [a.strip() for a in args.set_aliases.split(",") if a.strip()]
    if args.set_nutrition:
        try:
            update_fields["nutrition"] = json.loads(args.set_nutrition)
        except json.JSONDecodeError:
            print(f"Error: --set-nutrition must be valid JSON", file=sys.stderr)
            sys.exit(1)
    if args.set_extra:
        try:
            extra = json.loads(args.set_extra)
            update_fields.update(extra)
        except json.JSONDecodeError:
            print(f"Error: --set-extra must be valid JSON", file=sys.stderr)
            sys.exit(1)
    if args.unset:
        for field in args.unset:
            update_fields[field] = ""

    if not update_fields:
        print("Error: nothing to update", file=sys.stderr)
        sys.exit(1)

    set_doc = {"$set": {k: v for k, v in update_fields.items()}}
    unset_doc = {"$unset": {k: v for k, v in update_fields.items() if v == ""}}

    update = {}
    if set_doc["$set"]:
        update["$set"] = set_doc["$set"]
    if unset_doc["$unset"]:
        update["$unset"] = unset_doc["$unset"]

    result = coll.update_one(query, update)
    print(f"Matched: {result.matched_count}, Modified: {result.modified_count}")

    if result.matched_count:
        updated = coll.find_one(query)
        updated["_id"] = str(updated["_id"])
        print(json.dumps(updated, indent=2, default=str))
    else:
        print("No matching item found.")
    client.close()

def main():
    parser = argparse.ArgumentParser(description="Manage food items in lists.food_items")
    sub = parser.add_subparsers(dest="command", required=True)

    # add
    p_add = sub.add_parser("add", help="Add a new food item")
    p_add.add_argument("--name", required=True)
    p_add.add_argument("--type")
    p_add.add_argument("--serving")
    p_add.add_argument("--description")
    p_add.add_argument("--max-dosage")
    p_add.add_argument("--aliases", help="Comma-separated alias names, e.g. \"large bread,large toast\"")
    p_add.add_argument("--nutrition", help='JSON string, e.g. \'{"calories": 228, "protein_g": 12}\'')
    p_add.add_argument("--extra", help="JSON string with additional fields to merge into the document")

    # get
    p_get = sub.add_parser("get", help="Get food items")
    p_get.add_argument("--name", help="Filter by name (regex)")
    p_get.add_argument("--type", help="Filter by type (regex)")
    p_get.add_argument("--limit", type=int, help="Max items to return")

    # update
    p_upd = sub.add_parser("update", help="Update an existing food item")
    p_upd.add_argument("--id", help="ObjectId to update")
    p_upd.add_argument("--name", help="Name to match (if no --id)")
    p_upd.add_argument("--set-name", dest="set_name")
    p_upd.add_argument("--set-type", dest="set_type")
    p_upd.add_argument("--set-serving", dest="set_serving")
    p_upd.add_argument("--set-description", dest="set_description")
    p_upd.add_argument("--set-max-dosage", dest="set_max_dosage")
    p_upd.add_argument("--set-aliases", dest="set_aliases", help="Comma-separated alias names (replaces existing)")
    p_upd.add_argument("--set-nutrition", dest="set_nutrition", help="JSON string to replace nutrition")
    p_upd.add_argument("--set-extra", dest="set_extra", help="JSON string with additional fields to set")
    p_upd.add_argument("--unset", nargs="*", help="Field names to remove")

    args = parser.parse_args()
    {"add": cmd_add, "get": cmd_get, "update": cmd_update}[args.command](args)

if __name__ == "__main__":
    main()