Collections Project

from collections import defaultdict
import json
import os

DATA_FILE = "contacts.json"

class ContactBook:
    """A simple contact book using Python collections."""

    def __init__(self):
        self.contacts = {}  # {name: {"phone": str, "email": str, "tags": set}}
        self._load()

    def _load(self):
        """Load contacts from JSON file."""
        if os.path.exists(DATA_FILE):
            with open(DATA_FILE) as f:
                raw = json.load(f)
            # Convert tags back to sets
            for name, info in raw.items():
                info["tags"] = set(info["tags"])
            self.contacts = raw

    def _save(self):
        """Save contacts to JSON file."""
        to_save = {}
        for name, info in self.contacts.items():
            to_save[name] = {**info, "tags": list(info["tags"])}
        with open(DATA_FILE, "w") as f:
            json.dump(to_save, f, indent=2)

    def add(self, name, phone, email, tags=None):
        """Add or update a contact."""
        if name not in self.contacts:
            self.contacts[name] = {"phone": "", "email": "", "tags": set()}

        self.contacts[name]["phone"] = phone
        self.contacts[name]["email"] = email
        if tags:
            self.contacts[name]["tags"] |= set(tags)  # Union with existing tags

        self._save()
        print(f"Saved contact: {name}")

    def search(self, query):
        """Search contacts by name, phone, or email."""
        query = query.lower()
        results = []
        for name, info in self.contacts.items():
            if (query in name.lower()
                    or query in info["phone"]
                    or query in info["email"].lower()):
                results.append((name, info))
        return results

    def get_by_tag(self, tag):
        """Get all contacts with a specific tag."""
        return [(name, info)
                for name, info in self.contacts.items()
                if tag in info["tags"]]

    def get_all_tags(self):
        """Get all unique tags across all contacts."""
        all_tags = set()
        for info in self.contacts.values():
            all_tags |= info["tags"]
        return sorted(all_tags)

    def list_all(self):
        """Return all contacts sorted by name."""
        return sorted(self.contacts.items())

    def delete(self, name):
        """Delete a contact."""
        if name in self.contacts:
            del self.contacts[name]
            self._save()
            print(f"Deleted: {name}")
        else:
            print(f"Contact not found: {name}")

    def merge_duplicates(self):
        """Merge contacts with the same phone number."""
        by_phone = defaultdict(list)
        for name, info in self.contacts.items():
            by_phone[info["phone"]].append((name, info))

        merged = {}
        for phone, matches in by_phone.items():
            if len(matches) > 1:
                # Merge into the first entry
                primary_name, primary_info = matches[0]
                primary_info["tags"] = set()
                for _, info in matches:
                    primary_info["tags"] |= info["tags"]
                merged[primary_name] = primary_info
            else:
                name, info = matches[0]
                merged[name] = info

        self.contacts = merged
        self._save()


def main():
    book = ContactBook()

    while True:
        print("\n=== Contact Book ===")
        print("1. Add contact")
        print("2. Search contacts")
        print("3. List all")
        print("4. Search by tag")
        print("5. Delete contact")
        print("6. Show all tags")
        print("7. Exit")

        choice = input("\nChoose: ")

        if choice == "1":
            name = input("Name: ")
            phone = input("Phone: ")
            email = input("Email: ")
            tags = input("Tags (comma-separated): ").split(",")
            tags = [t.strip() for t in tags if t.strip()]
            book.add(name, phone, email, tags)

        elif choice == "2":
            query = input("Search: ")
            results = book.search(query)
            if results:
                for name, info in results:
                    tags = ", ".join(sorted(info["tags"]))
                    print(f"\n{name}")
                    print(f"  Phone: {info['phone']}")
                    print(f"  Email: {info['email']}")
                    print(f"  Tags: [{tags}]")
            else:
                print("No results found.")

        elif choice == "3":
            contacts = book.list_all()
            if contacts:
                for name, info in contacts:
                    print(f"{name} — {info['phone']}")
            else:
                print("No contacts yet.")

        elif choice == "4":
            tag = input("Tag: ")
            results = book.get_by_tag(tag)
            if results:
                for name, info in results:
                    print(f"{name} — {info['phone']}")
            else:
                print(f"No contacts with tag: {tag}")

        elif choice == "5":
            name = input("Name to delete: ")
            book.delete(name)

        elif choice == "6":
            tags = book.get_all_tags()
            if tags:
                print("All tags:", ", ".join(tags))
            else:
                print("No tags yet.")

        elif choice == "7":
            print("Goodbye!")
            break

        else:
            print("Invalid choice.")

if __name__ == "__main__":
    main()