Random Quote Generator

import json

import random

import os

from datetime import datetime

from pathlib import Path

from collections import defaultdict


try:

    import requests

    REQUESTS_OK = True

except ImportError:

    REQUESTS_OK = False


# ============================================================

# CONFIGURATION

# ============================================================


QUOTES_FILE    = "quotes.json"

FAVORITES_FILE = "favorite_quotes.json"

HISTORY_FILE   = "quote_history.json"


# Free API — no key needed

QUOTE_API_URL  = "https://api.quotable.io/random"

QUOTES_BY_TAG  = "https://api.quotable.io/quotes?tags={tag}&limit=20"


# ============================================================

# BUILT-IN QUOTE DATABASE (works offline)

# ============================================================


BUILTIN_QUOTES = [

    # Motivation

    {"text": "The only way to do great work is to love what you do.", "author": "Steve Jobs", "category": "motivation"},

    {"text": "It does not matter how slowly you go as long as you do not stop.", "author": "Confucius", "category": "motivation"},

    {"text": "Success is not final, failure is not fatal: it is the courage to continue that counts.", "author": "Winston Churchill", "category": "motivation"},

    {"text": "Believe you can and you're halfway there.", "author": "Theodore Roosevelt", "category": "motivation"},

    {"text": "The secret of getting ahead is getting started.", "author": "Mark Twain", "category": "motivation"},

    {"text": "Don't watch the clock; do what it does. Keep going.", "author": "Sam Levenson", "category": "motivation"},

    {"text": "You are never too old to set another goal or to dream a new dream.", "author": "C.S. Lewis", "category": "motivation"},

    {"text": "The future belongs to those who believe in the beauty of their dreams.", "author": "Eleanor Roosevelt", "category": "motivation"},


    # Wisdom

    {"text": "In the middle of every difficulty lies opportunity.", "author": "Albert Einstein", "category": "wisdom"},

    {"text": "Life is what happens when you're busy making other plans.", "author": "John Lennon", "category": "wisdom"},

    {"text": "The only true wisdom is in knowing you know nothing.", "author": "Socrates", "category": "wisdom"},

    {"text": "Yesterday is history, tomorrow is a mystery, today is a gift of God.", "author": "Bill Keane", "category": "wisdom"},

    {"text": "We do not remember days, we remember moments.", "author": "Cesare Pavese", "category": "wisdom"},

    {"text": "The unexamined life is not worth living.", "author": "Socrates", "category": "wisdom"},

    {"text": "He who knows others is wise; he who knows himself is enlightened.", "author": "Lao Tzu", "category": "wisdom"},

    {"text": "The journey of a thousand miles begins with one step.", "author": "Lao Tzu", "category": "wisdom"},


    # Success

    {"text": "Success usually comes to those who are too busy to be looking for it.", "author": "Henry David Thoreau", "category": "success"},

    {"text": "I find that the harder I work, the more luck I seem to have.", "author": "Thomas Jefferson", "category": "success"},

    {"text": "Don't be afraid to give up the good to go for the great.", "author": "John D. Rockefeller", "category": "success"},

    {"text": "I have not failed. I've just found 10,000 ways that won't work.", "author": "Thomas Edison", "category": "success"},

    {"text": "The road to success and the road to failure are almost exactly the same.", "author": "Colin R. Davis", "category": "success"},

    {"text": "Success is walking from failure to failure with no loss of enthusiasm.", "author": "Winston Churchill", "category": "success"},


    # Happiness

    {"text": "Happiness is not something ready-made. It comes from your own actions.", "author": "Dalai Lama", "category": "happiness"},

    {"text": "For every minute you are angry you lose sixty seconds of happiness.", "author": "Ralph Waldo Emerson", "category": "happiness"},

    {"text": "The most wasted of days is one without laughter.", "author": "E.E. Cummings", "category": "happiness"},

    {"text": "Count your age by friends, not years. Count your life by smiles, not tears.", "author": "John Lennon", "category": "happiness"},

    {"text": "Happiness depends upon ourselves.", "author": "Aristotle", "category": "happiness"},


    # Technology

    {"text": "Any sufficiently advanced technology is indistinguishable from magic.", "author": "Arthur C. Clarke", "category": "technology"},

    {"text": "It's not a faith in technology. It's faith in people.", "author": "Steve Jobs", "category": "technology"},

    {"text": "The science of today is the technology of tomorrow.", "author": "Edward Teller", "category": "technology"},

    {"text": "Technology is best when it brings people together.", "author": "Matt Mullenweg", "category": "technology"},

    {"text": "The real danger is not that computers will begin to think like men, but that men will begin to think like computers.", "author": "Sydney J. Harris", "category": "technology"},


    # Programming

    {"text": "First, solve the problem. Then, write the code.", "author": "John Johnson", "category": "programming"},

    {"text": "Programs must be written for people to read, and only incidentally for machines to execute.", "author": "Harold Abelson", "category": "programming"},

    {"text": "Any fool can write code that a computer can understand. Good programmers write code that humans can understand.", "author": "Martin Fowler", "category": "programming"},

    {"text": "The most important property of a program is whether it accomplishes the intention of its user.", "author": "C.A.R. Hoare", "category": "programming"},

    {"text": "Debugging is twice as hard as writing the code in the first place.", "author": "Brian Kernighan", "category": "programming"},

    {"text": "Talk is cheap. Show me the code.", "author": "Linus Torvalds", "category": "programming"},

    {"text": "Clean code always looks like it was written by someone who cares.", "author": "Robert C. Martin", "category": "programming"},

    {"text": "Simplicity is the soul of efficiency.", "author": "Austin Freeman", "category": "programming"},


    # Life

    {"text": "Life is short, and it's up to you to make it sweet.", "author": "Sarah Louise Delany", "category": "life"},

    {"text": "In three words I can sum up everything I've learned about life: it goes on.", "author": "Robert Frost", "category": "life"},

    {"text": "To live is the rarest thing in the world. Most people exist, that is all.", "author": "Oscar Wilde", "category": "life"},

    {"text": "Life is really simple, but we insist on making it complicated.", "author": "Confucius", "category": "life"},

    {"text": "The purpose of life is not to be happy but to be useful.", "author": "Ralph Waldo Emerson", "category": "life"},


    # Courage

    {"text": "You gain strength, courage, and confidence by every experience in which you really stop to look fear in the face.", "author": "Eleanor Roosevelt", "category": "courage"},

    {"text": "Courage is not the absence of fear, but the triumph over it.", "author": "Nelson Mandela", "category": "courage"},

    {"text": "It takes courage to grow up and become who you really are.", "author": "E.E. Cummings", "category": "courage"},

    {"text": "Fortune favors the brave.", "author": "Virgil", "category": "courage"},


    # Learning

    {"text": "Live as if you were to die tomorrow. Learn as if you were to live forever.", "author": "Mahatma Gandhi", "category": "learning"},

    {"text": "An investment in knowledge pays the best interest.", "author": "Benjamin Franklin", "category": "learning"},

    {"text": "Education is the most powerful weapon which you can use to change the world.", "author": "Nelson Mandela", "category": "learning"},

    {"text": "The beautiful thing about learning is that no one can take it away from you.", "author": "B.B. King", "category": "learning"},

    {"text": "Tell me and I forget. Teach me and I remember. Involve me and I learn.", "author": "Benjamin Franklin", "category": "learning"},

]


# ============================================================

# LOAD & SAVE

# ============================================================


def load_quotes():

    if Path(QUOTES_FILE).exists():

        try:

            with open(QUOTES_FILE, "r", encoding="utf-8") as f:

                return json.load(f)

        except:

            pass

    # First run — save built-in quotes

    save_quotes(BUILTIN_QUOTES)

    return BUILTIN_QUOTES



def save_quotes(quotes):

    with open(QUOTES_FILE, "w", encoding="utf-8") as f:

        json.dump(quotes, f, indent=2, ensure_ascii=False)



def load_favorites():

    if Path(FAVORITES_FILE).exists():

        try:

            with open(FAVORITES_FILE, "r", encoding="utf-8") as f:

                return json.load(f)

        except:

            pass

    return []



def save_favorites(favs):

    with open(FAVORITES_FILE, "w", encoding="utf-8") as f:

        json.dump(favs, f, indent=2, ensure_ascii=False)



def load_history():

    if Path(HISTORY_FILE).exists():

        try:

            with open(HISTORY_FILE, "r", encoding="utf-8") as f:

                return json.load(f)

        except:

            pass

    return []



def save_to_history(quote):

    history = load_history()

    history.append({

        "text":     quote["text"],

        "author":   quote["author"],

        "category": quote.get("category", ""),

        "shown_at": datetime.now().strftime("%d-%m-%Y %H:%M:%S"),

    })

    history = history[-100:]

    with open(HISTORY_FILE, "w", encoding="utf-8") as f:

        json.dump(history, f, indent=2, ensure_ascii=False)



# ============================================================

# DISPLAY QUOTE

# ============================================================


def display_quote(quote, show_box=True):

    text     = quote.get("text", "")

    author   = quote.get("author", "Unknown")

    category = quote.get("category", "")


    if show_box:

        width = min(max(len(text) + 6, 50), 65)

        print("\n" + "─" * width)


        # Word-wrap text

        words   = text.split()

        lines   = []

        current = ""

        for word in words:

            if len(current) + len(word) + 1 <= width - 6:

                current = current + " " + word if current else word

            else:

                lines.append(current)

                current = word

        if current:

            lines.append(current)


        for line in lines:

            print(f"  {line}")


        print(f"\n  — {author}")

        if category:

            print(f"  [{category}]")

        print("─" * width)

    else:

        print(f"\n  \"{text}\"")

        print(f"  — {author}")

        if category:

            print(f"  [{category}]")



# ============================================================

# FETCH FROM API

# ============================================================


def fetch_online_quote(tag=None):

    if not REQUESTS_OK:

        return None

    try:

        url  = QUOTES_BY_TAG.format(tag=tag) if tag else QUOTE_API_URL

        resp = requests.get(url, timeout=8)

        resp.raise_for_status()

        data = resp.json()


        # quotable.io returns either a single object or {results: [...]}

        if "results" in data:

            items = data["results"]

            if not items:

                return None

            item = random.choice(items)

        else:

            item = data


        return {

            "text":     item.get("content", ""),

            "author":   item.get("author", "Unknown"),

            "category": tag or "online",

        }

    except Exception as e:

        return None



# ============================================================

# GET RANDOM QUOTE

# ============================================================


def get_random_quote(quotes, category=None):

    pool = quotes

    if category:

        pool = [q for q in quotes if q.get("category", "").lower() == category.lower()]

        if not pool:

            print(f"  No quotes in category '{category}'. Showing random.")

            pool = quotes

    return random.choice(pool) if pool else None



# ============================================================

# QUOTE OF THE DAY

# ============================================================


def quote_of_the_day(quotes):

    """Deterministic quote based on today's date — same quote all day."""

    today_num = int(datetime.now().strftime("%Y%j"))

    idx       = today_num % len(quotes)

    quote     = quotes[idx]


    print("\n" + "="*55)

    print(f"  QUOTE OF THE DAY  —  {datetime.now().strftime('%d %B %Y')}")

    print("="*55)

    display_quote(quote)



# ============================================================

# ADD CUSTOM QUOTE

# ============================================================


def add_quote(quotes):

    print("\n  ADD YOUR OWN QUOTE")

    print("  " + "-"*40)


    text   = input("  Quote text  : ").strip()

    author = input("  Author      : ").strip() or "Unknown"


    # Show categories

    cats = sorted(set(q.get("category", "") for q in quotes if q.get("category")))

    print(f"  Categories  : {', '.join(cats)}")

    category = input("  Category    : ").strip().lower() or "general"


    if not text:

        print("  Quote text is required.")

        return quotes


    quote = {

        "text":     text,

        "author":   author,

        "category": category,

        "custom":   True,

        "added_at": datetime.now().strftime("%d-%m-%Y %H:%M"),

    }

    quotes.append(quote)

    save_quotes(quotes)

    print(f"\n  Quote added! Total quotes: {len(quotes)}")

    return quotes



# ============================================================

# SEARCH QUOTES

# ============================================================


def search_quotes(quotes, keyword):

    keyword = keyword.lower()

    results = [

        q for q in quotes

        if keyword in q["text"].lower()

        or keyword in q["author"].lower()

        or keyword in q.get("category", "").lower()

    ]


    if not results:

        print(f"\n  No quotes found for: '{keyword}'")

        return


    print(f"\n  Found {len(results)} quote(s) for '{keyword}':\n")

    for i, q in enumerate(results[:10], 1):

        print(f"  [{i}] \"{q['text'][:70]}{'...' if len(q['text']) > 70 else ''}\"")

        print(f"       — {q['author']}  [{q.get('category', '')}]\n")


    if len(results) > 10:

        print(f"  ... and {len(results) - 10} more.")



# ============================================================

# FAVORITES

# ============================================================


def add_to_favorites(quote):

    favs = load_favorites()

    if any(f["text"] == quote["text"] for f in favs):

        print("  Already in favorites.")

        return

    favs.append({

        "text":     quote["text"],

        "author":   quote["author"],

        "category": quote.get("category", ""),

        "saved_at": datetime.now().strftime("%d-%m-%Y %H:%M"),

    })

    save_favorites(favs)

    print("  Added to favorites!")



def view_favorites():

    favs = load_favorites()

    if not favs:

        print("\n  No favorites yet.")

        return


    print("\n" + "="*55)

    print(f"  FAVORITE QUOTES  ({len(favs)})")

    print("="*55)

    for i, q in enumerate(favs, 1):

        print(f"\n  [{i}]")

        display_quote(q, show_box=False)


    print("="*55)



def remove_from_favorites():

    favs = load_favorites()

    if not favs:

        print("\n  No favorites to remove.")

        return


    view_favorites()

    try:

        idx = int(input("\n  Enter number to remove: ").strip()) - 1

        if 0 <= idx < len(favs):

            removed = favs.pop(idx)

            save_favorites(favs)

            print(f"  Removed: \"{removed['text'][:50]}...\"")

        else:

            print("  Invalid number.")

    except ValueError:

        print("  Invalid input.")



# ============================================================

# CATEGORY STATS

# ============================================================


def show_stats(quotes):

    total      = len(quotes)

    categories = defaultdict(int)

    authors    = defaultdict(int)

    custom     = sum(1 for q in quotes if q.get("custom"))


    for q in quotes:

        categories[q.get("category", "uncategorized")] += 1

        authors[q.get("author", "Unknown")] += 1


    print("\n" + "="*50)

    print(f"  QUOTE LIBRARY STATS")

    print("="*50)

    print(f"  Total quotes   : {total}")

    print(f"  Custom quotes  : {custom}")

    print(f"  Favorites      : {len(load_favorites())}")

    print(f"  Categories     : {len(categories)}")

    print(f"  Authors        : {len(authors)}")


    print(f"\n  BY CATEGORY:")

    max_count = max(categories.values()) if categories else 1

    for cat, count in sorted(categories.items(), key=lambda x: -x[1]):

        bar = "█" * int((count / max_count) * 20)

        print(f"  {cat:<18} {count:>4}  {bar}")


    print(f"\n  TOP 5 AUTHORS:")

    for author, count in sorted(authors.items(), key=lambda x: -x[1])[:5]:

        print(f"  {author:<30} {count} quote(s)")


    print("="*50)



# ============================================================

# QUOTE SLIDESHOW

# ============================================================


def slideshow(quotes, category=None, count=5):

    """Display N quotes one by one."""

    pool = quotes

    if category:

        pool = [q for q in quotes

                if q.get("category", "").lower() == category.lower()]

        if not pool:

            pool = quotes


    sample = random.sample(pool, min(count, len(pool)))


    print(f"\n  SLIDESHOW  —  {len(sample)} quotes")

    print("  Press Enter for next, 'f' to favorite, 'q' to quit\n")


    for i, quote in enumerate(sample, 1):

        print(f"\n  Quote {i} of {len(sample)}")

        display_quote(quote)

        save_to_history(quote)


        action = input("\n  [Enter=next | f=favorite | q=quit]: ").strip().lower()

        if action == "f":

            add_to_favorites(quote)

        elif action == "q":

            break



# ============================================================

# VIEW HISTORY

# ============================================================


def view_history():

    history = load_history()

    if not history:

        print("\n  No quote history yet.")

        return


    print("\n" + "="*60)

    print(f"  RECENTLY VIEWED QUOTES  (last {min(len(history), 10)})")

    print("="*60)


    for h in reversed(history[-10:]):

        print(f"\n  {h['shown_at']}  [{h.get('category', '')}]")

        print(f"  \"{h['text'][:70]}{'...' if len(h['text']) > 70 else ''}\"")

        print(f"  — {h['author']}")


    print("="*60)



# ============================================================

# MAIN MENU

# ============================================================


def print_menu(quotes):

    cats  = sorted(set(q.get("category", "") for q in quotes if q.get("category")))

    total = len(quotes)

    favs  = len(load_favorites())

    print("\n" + "-"*50)

    print(f"  RANDOM QUOTE GENERATOR  [{total} quotes | ★{favs} favs]")

    print("-"*50)

    print("  1.  Random quote")

    print("  2.  Quote by category")

    print("  3.  Quote of the day")

    print("  4.  Quote slideshow")

    print("  5.  Fetch online quote (API)")

    print("  6.  Search quotes")

    print("  7.  Add your own quote")

    print("  8.  View favorites")

    print("  9.  Remove from favorites")

    print("  10. View history")

    print("  11. Library stats")

    print("  0.  Exit")

    print(f"\n  Categories: {', '.join(cats)}")

    print("-"*50)



def main():

    print("\n" + "="*55)

    print("     RANDOM QUOTE GENERATOR")

    print("="*55)


    quotes = load_quotes()

    print(f"\n  Loaded {len(quotes)} quotes from library.")

    print("  Works offline with built-in quotes.")

    if REQUESTS_OK:

        print("  Online API enabled (quotable.io).")


    while True:

        print_menu(quotes)

        choice = input("  > ").strip()


        if choice == "1":

            quote = get_random_quote(quotes)

            if quote:

                display_quote(quote)

                save_to_history(quote)

                fav = input("\n  Add to favorites? (y/n): ").strip().lower()

                if fav == "y":

                    add_to_favorites(quote)


        elif choice == "2":

            cats = sorted(set(q.get("category", "") for q in quotes if q.get("category")))

            print(f"\n  Available: {', '.join(cats)}")

            cat = input("  Category: ").strip()

            quote = get_random_quote(quotes, cat)

            if quote:

                display_quote(quote)

                save_to_history(quote)

                fav = input("\n  Add to favorites? (y/n): ").strip().lower()

                if fav == "y":

                    add_to_favorites(quote)


        elif choice == "3":

            quote_of_the_day(quotes)


        elif choice == "4":

            cats = sorted(set(q.get("category", "") for q in quotes if q.get("category")))

            print(f"\n  Categories: {', '.join(cats)}")

            cat = input("  Category (Enter=all): ").strip() or None

            try:

                n = int(input("  Number of quotes (default 5): ").strip() or 5)

            except ValueError:

                n = 5

            slideshow(quotes, cat, n)


        elif choice == "5":

            if not REQUESTS_OK:

                print("\n  requests not installed: pip install requests")

            else:

                print("\n  Popular tags: inspirational, life, humor, love, technology")

                tag   = input("  Tag (Enter=random): ").strip() or None

                print("  Fetching...")

                quote = fetch_online_quote(tag)

                if quote:

                    display_quote(quote)

                    save_to_history(quote)

                    # Offer to save to local library

                    save = input("\n  Save to local library? (y/n): ").strip().lower()

                    if save == "y":

                        quotes.append(quote)

                        save_quotes(quotes)

                        print("  Saved!")

                    fav = input("  Add to favorites? (y/n): ").strip().lower()

                    if fav == "y":

                        add_to_favorites(quote)

                else:

                    print("  Could not fetch online quote. Check internet connection.")


        elif choice == "6":

            kw = input("\n  Search keyword: ").strip()

            if kw:

                search_quotes(quotes, kw)


        elif choice == "7":

            quotes = add_quote(quotes)


        elif choice == "8":

            view_favorites()


        elif choice == "9":

            remove_from_favorites()


        elif choice == "10":

            view_history()


        elif choice == "11":

            show_stats(quotes)


        elif choice == "0":

            print("\n  Goodbye! Stay inspired!\n")

            break


        else:

            print("  Invalid choice.")



# ============================================================

# RUN

# ============================================================


if __name__ == "__main__":

    main()

Unit Converter

 


import os

import json

from datetime import datetime

from pathlib import Path

from collections import defaultdict


# ============================================================

# CONVERSION DATA

# ============================================================


CATEGORIES = {


    # ── LENGTH ──────────────────────────────────────────────

    "length": {

        "base":  "meter",

        "units": {

            "meter":      1,

            "kilometer":  1000,

            "centimeter": 0.01,

            "millimeter": 0.001,

            "micrometer": 1e-6,

            "nanometer":  1e-9,

            "mile":       1609.344,

            "yard":       0.9144,

            "foot":       0.3048,

            "inch":       0.0254,

            "nautical mile": 1852,

            "light year": 9.461e15,

        }

    },


    # ── WEIGHT / MASS ────────────────────────────────────────

    "weight": {

        "base":  "kilogram",

        "units": {

            "kilogram":     1,

            "gram":         0.001,

            "milligram":    1e-6,

            "microgram":    1e-9,

            "metric ton":   1000,

            "pound":        0.453592,

            "ounce":        0.0283495,

            "stone":        6.35029,

            "quintal":      100,

            "carat":        0.0002,

        }

    },


    # ── TEMPERATURE ──────────────────────────────────────────

    "temperature": {

        "base":  "celsius",

        "units": {

            "celsius":    None,   # special handling

            "fahrenheit": None,

            "kelvin":     None,

            "rankine":    None,

        }

    },


    # ── VOLUME ───────────────────────────────────────────────

    "volume": {

        "base":  "liter",

        "units": {

            "liter":          1,

            "milliliter":     0.001,

            "cubic meter":    1000,

            "cubic centimeter": 0.001,

            "cubic inch":     0.0163871,

            "cubic foot":     28.3168,

            "gallon (US)":    3.78541,

            "gallon (UK)":    4.54609,

            "quart (US)":     0.946353,

            "pint (US)":      0.473176,

            "cup (US)":       0.236588,

            "fluid ounce":    0.0295735,

            "tablespoon":     0.0147868,

            "teaspoon":       0.00492892,

        }

    },


    # ── SPEED ────────────────────────────────────────────────

    "speed": {

        "base":  "meter/second",

        "units": {

            "meter/second":    1,

            "kilometer/hour":  0.277778,

            "mile/hour":       0.44704,

            "foot/second":     0.3048,

            "knot":            0.514444,

            "mach":            340.29,

            "light speed":     299792458,

        }

    },


    # ── AREA ─────────────────────────────────────────────────

    "area": {

        "base":  "square meter",

        "units": {

            "square meter":      1,

            "square kilometer":  1e6,

            "square centimeter": 1e-4,

            "square millimeter": 1e-6,

            "square mile":       2589988.11,

            "square yard":       0.836127,

            "square foot":       0.092903,

            "square inch":       6.4516e-4,

            "hectare":           10000,

            "acre":              4046.86,

            "cent":              40.4686,    # Indian unit

            "bigha":             2508.38,    # common Indian unit

        }

    },


    # ── TIME ─────────────────────────────────────────────────

    "time": {

        "base":  "second",

        "units": {

            "second":       1,

            "millisecond":  0.001,

            "microsecond":  1e-6,

            "nanosecond":   1e-9,

            "minute":       60,

            "hour":         3600,

            "day":          86400,

            "week":         604800,

            "month":        2628000,   # avg 30.44 days

            "year":         31536000,

            "decade":       315360000,

            "century":      3153600000,

        }

    },


    # ── DATA / STORAGE ───────────────────────────────────────

    "data": {

        "base":  "byte",

        "units": {

            "bit":       0.125,

            "byte":      1,

            "kilobyte":  1024,

            "megabyte":  1024**2,

            "gigabyte":  1024**3,

            "terabyte":  1024**4,

            "petabyte":  1024**5,

            "kibibyte":  1024,

            "mebibyte":  1024**2,

            "gibibyte":  1024**3,

        }

    },


    # ── PRESSURE ─────────────────────────────────────────────

    "pressure": {

        "base":  "pascal",

        "units": {

            "pascal":      1,

            "kilopascal":  1000,

            "megapascal":  1e6,

            "bar":         100000,

            "millibar":    100,

            "atmosphere":  101325,

            "psi":         6894.76,

            "mmHg":        133.322,

            "torr":        133.322,

            "inHg":        3386.39,

        }

    },


    # ── ENERGY ───────────────────────────────────────────────

    "energy": {

        "base":  "joule",

        "units": {

            "joule":          1,

            "kilojoule":      1000,

            "megajoule":      1e6,

            "calorie":        4.184,

            "kilocalorie":    4184,

            "watt-hour":      3600,

            "kilowatt-hour":  3.6e6,

            "electronvolt":   1.602e-19,

            "BTU":            1055.06,

            "therm":          105480400,

            "foot-pound":     1.35582,

        }

    },


    # ── FUEL EFFICIENCY ──────────────────────────────────────

    "fuel": {

        "base":  "km/l",

        "units": {

            "km/l":    1,

            "l/100km": None,   # inverse — special handling

            "mpg (US)": 0.425144,

            "mpg (UK)": 0.354006,

            "miles/l":  1.60934,

        }

    },


}


# ============================================================

# HISTORY FILE

# ============================================================


HISTORY_FILE = "unit_converter_history.json"


def load_history():

    if Path(HISTORY_FILE).exists():

        try:

            with open(HISTORY_FILE, "r") as f:

                return json.load(f)

        except:

            pass

    return []



def save_history(entry):

    history = load_history()

    history.append(entry)

    history = history[-50:]

    with open(HISTORY_FILE, "w") as f:

        json.dump(history, f, indent=2)



# ============================================================

# CONVERSION LOGIC

# ============================================================


def convert_temperature(value, from_unit, to_unit):

    """Special handling for temperature conversions."""

    # Convert to Celsius first

    if from_unit == "celsius":

        celsius = value

    elif from_unit == "fahrenheit":

        celsius = (value - 32) * 5 / 9

    elif from_unit == "kelvin":

        celsius = value - 273.15

    elif from_unit == "rankine":

        celsius = (value - 491.67) * 5 / 9

    else:

        return None


    # Convert from Celsius to target

    if to_unit == "celsius":

        return celsius

    elif to_unit == "fahrenheit":

        return celsius * 9 / 5 + 32

    elif to_unit == "kelvin":

        return celsius + 273.15

    elif to_unit == "rankine":

        return (celsius + 273.15) * 9 / 5

    return None



def convert_fuel(value, from_unit, to_unit):

    """Special handling for fuel efficiency (l/100km is inverse)."""

    # Convert to km/l first

    if from_unit == "l/100km":

        kml = 100 / value if value != 0 else 0

    else:

        factor = CATEGORIES["fuel"]["units"].get(from_unit, 1)

        kml    = value * factor


    # Convert from km/l to target

    if to_unit == "l/100km":

        return 100 / kml if kml != 0 else 0

    else:

        factor = CATEGORIES["fuel"]["units"].get(to_unit, 1)

        return kml / factor



def convert(value, from_unit, to_unit, category):

    """

    Universal conversion function.

    Returns converted value or None.

    """

    from_unit = from_unit.lower().strip()

    to_unit   = to_unit.lower().strip()


    if from_unit == to_unit:

        return value


    cat_data = CATEGORIES.get(category)

    if not cat_data:

        return None


    # Special categories

    if category == "temperature":

        return convert_temperature(value, from_unit, to_unit)

    if category == "fuel":

        return convert_fuel(value, from_unit, to_unit)


    units = cat_data["units"]


    if from_unit not in units or to_unit not in units:

        return None


    # Convert via base unit

    value_in_base = value * units[from_unit]

    result        = value_in_base / units[to_unit]

    return result



# ============================================================

# FORMAT RESULT

# ============================================================


def fmt_result(value):

    """Smart formatting: remove unnecessary decimals."""

    if value is None:

        return "N/A"

    if abs(value) >= 1e12 or (abs(value) < 1e-6 and value != 0):

        return f"{value:.6e}"

    if value == int(value):

        return f"{int(value):,}"

    if abs(value) >= 100:

        return f"{value:,.4f}"

    if abs(value) >= 1:

        return f"{value:.6f}".rstrip("0").rstrip(".")

    return f"{value:.10f}".rstrip("0").rstrip(".")



# ============================================================

# DISPLAY UNIT LIST

# ============================================================


def list_units(category):

    cat_data = CATEGORIES.get(category)

    if not cat_data:

        print(f"  Unknown category: {category}")

        return


    units = list(cat_data["units"].keys())

    print(f"\n  Units in '{category}':")

    print("  " + "-"*40)

    for i, unit in enumerate(units, 1):

        print(f"  {i:>3}. {unit}")

    print("  " + "-"*40)



# ============================================================

# QUICK CONVERT (ALL TO ONE)

# ============================================================


def convert_one_to_all(value, from_unit, category):

    """Show value converted to ALL units in the category."""

    cat_data = CATEGORIES.get(category)

    if not cat_data:

        return


    print(f"\n  {fmt_result(value)} {from_unit}  =")

    print("  " + "-"*45)


    for unit in cat_data["units"].keys():

        if unit == from_unit.lower():

            continue

        result = convert(value, from_unit, unit, category)

        if result is not None:

            print(f"  {fmt_result(result):<20}  {unit}")


    print("  " + "-"*45)



# ============================================================

# INTERACTIVE CONVERSION

# ============================================================


def do_convert(category):

    list_units(category)


    from_unit = input(f"\n  From unit: ").strip().lower()

    to_unit   = input(f"  To unit  : ").strip().lower()


    cat_data = CATEGORIES.get(category, {})

    units    = cat_data.get("units", {})


    # Fuzzy match

    def fuzzy_match(u, unit_list):

        if u in unit_list:

            return u

        matches = [k for k in unit_list if u in k or k in u]

        return matches[0] if matches else None


    from_unit = fuzzy_match(from_unit, units) or from_unit

    to_unit   = fuzzy_match(to_unit, units) or to_unit


    if from_unit not in units:

        print(f"  Unknown unit: {from_unit}")

        return

    if to_unit not in units:

        print(f"  Unknown unit: {to_unit}")

        return


    try:

        value = float(input(f"  Value     : ").strip())

    except ValueError:

        print("  Invalid value.")

        return


    result = convert(value, from_unit, to_unit, category)


    if result is None:

        print("  Conversion failed.")

        return


    print(f"\n  {'='*45}")

    print(f"  {fmt_result(value)} {from_unit}")

    print(f"  =  {fmt_result(result)} {to_unit}")

    print(f"  {'='*45}")


    # Show all option

    show_all = input("\n  Show conversion to ALL units? (y/n): ").strip().lower()

    if show_all == "y":

        convert_one_to_all(value, from_unit, category)


    # Save to history

    save_history({

        "time":     datetime.now().strftime("%d-%m-%Y %H:%M"),

        "category": category,

        "value":    value,

        "from":     from_unit,

        "result":   result,

        "to":       to_unit,

    })



# ============================================================

# QUICK CONVERTER (COMMON PAIRS)

# ============================================================


def quick_convert():

    print("\n  QUICK CONVERSIONS")

    print("  " + "-"*40)


    quick_pairs = [

        ("1",  "km",       "mile",       "length"),

        ("2",  "kg",       "pound",      "weight"),

        ("3",  "celsius",  "fahrenheit", "temperature"),

        ("4",  "liter",    "gallon (US)","volume"),

        ("5",  "meter/second", "km/hour","speed"),

        ("6",  "hectare",  "acre",       "area"),

        ("7",  "gigabyte", "megabyte",   "data"),

        ("8",  "bar",      "psi",        "pressure"),

        ("9",  "kilocalorie","joule",    "energy"),

        ("10", "km/l",     "mpg (US)",   "fuel"),

    ]


    for num, f, t, cat in quick_pairs:

        result = convert(1, f, t, cat)

        print(f"  {num:>3}. 1 {f:<18} = {fmt_result(result)} {t}")


    print("  " + "-"*40)

    print("\n  Enter a number to use that conversion,")

    choice = input("  or press Enter to go back: ").strip()


    if not choice:

        return


    # Find the pair

    selected = None

    for num, f, t, cat in quick_pairs:

        if choice == num:

            selected = (f, t, cat)

            break


    if not selected:

        return


    from_unit, to_unit, category = selected


    try:

        value = float(input(f"\n  Enter value in {from_unit}: ").strip())

    except ValueError:

        print("  Invalid value.")

        return


    result = convert(value, from_unit, to_unit, category)

    print(f"\n  {fmt_result(value)} {from_unit}  =  {fmt_result(result)} {to_unit}")


    save_history({

        "time":     datetime.now().strftime("%d-%m-%Y %H:%M"),

        "category": category,

        "value":    value,

        "from":     from_unit,

        "result":   result,

        "to":       to_unit,

    })



# ============================================================

# SHOW HISTORY

# ============================================================


def show_history():

    history = load_history()

    if not history:

        print("\n  No conversion history yet.")

        return


    print("\n" + "="*65)

    print(f"  CONVERSION HISTORY  (last {len(history)})")

    print("="*65)

    print(f"  {'TIME':<18} {'CAT':<14} {'FROM':<25} TO")

    print("  " + "-"*60)


    for h in reversed(history[-20:]):

        from_str = f"{fmt_result(h['value'])} {h['from']}"

        to_str   = f"{fmt_result(h['result'])} {h['to']}"

        print(f"  {h['time']:<18} {h['category']:<14} "

              f"{from_str:<25} {to_str}")

    print("="*65)



# ============================================================

# MAIN MENU

# ============================================================


def print_menu():

    print("\n" + "-"*50)

    print("  UNIT CONVERTER")

    print("-"*50)

    print("  1.  Length")

    print("  2.  Weight / Mass")

    print("  3.  Temperature")

    print("  4.  Volume")

    print("  5.  Speed")

    print("  6.  Area")

    print("  7.  Time")

    print("  8.  Data / Storage")

    print("  9.  Pressure")

    print("  10. Energy")

    print("  11. Fuel Efficiency")

    print("  12. Quick conversions (common pairs)")

    print("  13. Conversion history")

    print("  0.  Exit")

    print("-"*50)



MENU_MAP = {

    "1":  "length",

    "2":  "weight",

    "3":  "temperature",

    "4":  "volume",

    "5":  "speed",

    "6":  "area",

    "7":  "time",

    "8":  "data",

    "9":  "pressure",

    "10": "energy",

    "11": "fuel",

}



def main():

    print("\n" + "="*55)

    print("     UNIT CONVERTER")

    print("="*55)

    print(f"\n  {len(CATEGORIES)} categories  |  "

          f"{sum(len(v['units']) for v in CATEGORIES.values())}+ units")

    print("  Length, Weight, Temperature, Volume, Speed,")

    print("  Area, Time, Data, Pressure, Energy, Fuel")


    while True:

        print_menu()

        choice = input("  > ").strip()


        if choice in MENU_MAP:

            do_convert(MENU_MAP[choice])


        elif choice == "12":

            quick_convert()


        elif choice == "13":

            show_history()


        elif choice == "0":

            print("\n  Goodbye!\n")

            break


        else:

            print("  Invalid choice.")



# ============================================================

# RUN

# ============================================================


if __name__ == "__main__":

    main()

Contact Book Manager

 import json

import csv

import os

import re

from datetime import datetime

from pathlib import Path


# ============================================================

# CONFIGURATION

# ============================================================


DATA_FILE   = "contacts.json"

BACKUP_FILE = "contacts_backup.json"


# ============================================================

# LOAD & SAVE

# ============================================================


def load_contacts():

    if Path(DATA_FILE).exists():

        try:

            with open(DATA_FILE, "r", encoding="utf-8") as f:

                return json.load(f)

        except:

            pass

    return {"contacts": [], "groups": []}



def save_contacts(data):

    with open(DATA_FILE, "w", encoding="utf-8") as f:

        json.dump(data, f, indent=2, ensure_ascii=False)



def backup_contacts(data):

    with open(BACKUP_FILE, "w", encoding="utf-8") as f:

        json.dump(data, f, indent=2, ensure_ascii=False)

    print(f"  Backup saved: {BACKUP_FILE}")



# ============================================================

# VALIDATION

# ============================================================


def validate_phone(phone):

    """Accept digits, spaces, +, -, (, )"""

    return bool(re.match(r"^[\d\s\+\-\(\)]{7,20}$", phone.strip()))



def validate_email(email):

    return bool(re.match(r"^[\w\.\+\-]+@[\w\-]+\.[a-zA-Z]{2,}$", email.strip()))



# ============================================================

# ADD CONTACT

# ============================================================


def add_contact(data):

    print("\n" + "="*50)

    print("  ADD NEW CONTACT")

    print("="*50)


    # Required

    name = input("  Full Name*    : ").strip()

    if not name:

        print("  Name is required.")

        return


    # Check duplicate

    if any(c["name"].lower() == name.lower() for c in data["contacts"]):

        overwrite = input(f"  '{name}' already exists. Add anyway? (y/n): ").strip().lower()

        if overwrite != "y":

            return


    # Optional fields

    phone = input("  Phone Number  : ").strip()

    if phone and not validate_phone(phone):

        print("  Invalid phone format. Saving as-is.")


    email = input("  Email         : ").strip()

    if email and not validate_email(email):

        print("  Invalid email format. Saving as-is.")


    address   = input("  Address       : ").strip()

    birthday  = input("  Birthday (DD-MM-YYYY): ").strip()

    company   = input("  Company       : ").strip()

    notes     = input("  Notes         : ").strip()


    # Groups

    if data["groups"]:

        print(f"\n  Available groups: {', '.join(data['groups'])}")

    group = input("  Group (or new group name): ").strip()

    if group and group not in data["groups"]:

        data["groups"].append(group)


    contact = {

        "id":         len(data["contacts"]) + 1,

        "name":       name,

        "phone":      phone,

        "email":      email,

        "address":    address,

        "birthday":   birthday,

        "company":    company,

        "notes":      notes,

        "group":      group,

        "favourite":  False,

        "created_at": datetime.now().strftime("%d-%m-%Y %H:%M"),

        "updated_at": datetime.now().strftime("%d-%m-%Y %H:%M"),

    }


    data["contacts"].append(contact)

    save_contacts(data)

    print(f"\n  Contact saved: {name}")



# ============================================================

# VIEW CONTACT

# ============================================================


def view_contact(contact):

    w = 50

    fav = " ★" if contact.get("favourite") else ""

    print("\n" + "="*w)

    print(f"  {contact['name']}{fav}")

    print("="*w)


    fields = [

        ("Phone",    contact.get("phone",    "")),

        ("Email",    contact.get("email",    "")),

        ("Company",  contact.get("company",  "")),

        ("Address",  contact.get("address",  "")),

        ("Birthday", contact.get("birthday", "")),

        ("Group",    contact.get("group",    "")),

        ("Notes",    contact.get("notes",    "")),

        ("Added",    contact.get("created_at", "")),

        ("Updated",  contact.get("updated_at", "")),

    ]

    for label, value in fields:

        if value:

            print(f"  {label:<10}: {value}")


    print("="*w)



# ============================================================

# LIST CONTACTS

# ============================================================


def list_contacts(data, group_filter=None, favourites_only=False,

                  sort_by="name"):

    contacts = data["contacts"]


    if group_filter:

        contacts = [c for c in contacts

                    if c.get("group", "").lower() == group_filter.lower()]

    if favourites_only:

        contacts = [c for c in contacts if c.get("favourite")]


    if not contacts:

        print("\n  No contacts found.")

        return []


    # Sort

    if sort_by == "name":

        contacts = sorted(contacts, key=lambda c: c["name"].lower())

    elif sort_by == "company":

        contacts = sorted(contacts, key=lambda c: c.get("company", "").lower())

    elif sort_by == "group":

        contacts = sorted(contacts, key=lambda c: c.get("group", "").lower())

    elif sort_by == "recent":

        contacts = sorted(contacts, key=lambda c: c.get("updated_at", ""),

                          reverse=True)


    label = ""

    if group_filter:

        label = f"  Group: {group_filter}"

    elif favourites_only:

        label = "  Favourites"


    print("\n" + "="*65)

    print(f"  CONTACTS  ({len(contacts)} total){label}")

    print("="*65)

    print(f"  {'#':<5} {'NAME':<22} {'PHONE':<16} "

          f"{'EMAIL':<22} {'GRP'}")

    print("  " + "-"*60)


    for i, c in enumerate(contacts, 1):

        fav   = "★" if c.get("favourite") else " "

        name  = c["name"][:20]

        phone = c.get("phone", "")[:14]

        email = c.get("email", "")[:20]

        group = c.get("group", "")[:8]

        print(f"  {fav}{i:<4} {name:<22} {phone:<16} "

              f"{email:<22} {group}")


    print("="*65)

    return contacts



# ============================================================

# SEARCH CONTACTS

# ============================================================


def search_contacts(data, query):

    query = query.lower().strip()

    results = []


    for c in data["contacts"]:

        if (query in c["name"].lower()

                or query in c.get("phone", "").lower()

                or query in c.get("email", "").lower()

                or query in c.get("company", "").lower()

                or query in c.get("address", "").lower()

                or query in c.get("notes", "").lower()):

            results.append(c)


    if not results:

        print(f"\n  No contacts found for: '{query}'")

        return []


    print(f"\n  Found {len(results)} result(s) for '{query}':")

    for i, c in enumerate(results, 1):

        fav   = "★" if c.get("favourite") else " "

        phone = c.get("phone", "N/A")

        email = c.get("email", "")

        print(f"  {fav}[{i}] {c['name']}  |  {phone}  |  {email}")


    return results



# ============================================================

# EDIT CONTACT

# ============================================================


def edit_contact(data, contact):

    print(f"\n  Editing: {contact['name']}")

    print("  (Press Enter to keep current value)\n")


    fields = [

        ("name",     "Full Name",    contact.get("name", "")),

        ("phone",    "Phone",        contact.get("phone", "")),

        ("email",    "Email",        contact.get("email", "")),

        ("company",  "Company",      contact.get("company", "")),

        ("address",  "Address",      contact.get("address", "")),

        ("birthday", "Birthday",     contact.get("birthday", "")),

        ("notes",    "Notes",        contact.get("notes", "")),

        ("group",    "Group",        contact.get("group", "")),

    ]


    for key, label, current in fields:

        new_val = input(f"  {label:<12} [{current}]: ").strip()

        if new_val:

            contact[key] = new_val


    # Favourite toggle

    fav = input(f"  Favourite? (y/n) [{'+' if contact.get('favourite') else '-'}]: ").strip().lower()

    if fav == "y":

        contact["favourite"] = True

    elif fav == "n":

        contact["favourite"] = False


    contact["updated_at"] = datetime.now().strftime("%d-%m-%Y %H:%M")


    # Update in data

    for i, c in enumerate(data["contacts"]):

        if c["id"] == contact["id"]:

            data["contacts"][i] = contact

            break


    # Add new group if needed

    if contact["group"] and contact["group"] not in data["groups"]:

        data["groups"].append(contact["group"])


    save_contacts(data)

    print(f"\n  Contact updated: {contact['name']}")



# ============================================================

# DELETE CONTACT

# ============================================================


def delete_contact(data, contact):

    confirm = input(f"\n  Delete '{contact['name']}'? (yes/no): ").strip().lower()

    if confirm == "yes":

        data["contacts"] = [c for c in data["contacts"]

                            if c["id"] != contact["id"]]

        save_contacts(data)

        print(f"  Deleted: {contact['name']}")

    else:

        print("  Cancelled.")



# ============================================================

# BIRTHDAY REMINDERS

# ============================================================


def birthday_reminders(data):

    today     = datetime.today()

    upcoming  = []


    for c in data["contacts"]:

        bday = c.get("birthday", "")

        if not bday:

            continue

        try:

            bday_dt = datetime.strptime(bday, "%d-%m-%Y")

            # This year's birthday

            this_year = bday_dt.replace(year=today.year)

            if this_year < today:

                this_year = bday_dt.replace(year=today.year + 1)

            days_left = (this_year - today).days

            age = today.year - bday_dt.year

            if this_year.year > today.year:

                age -= 1

            upcoming.append((days_left, c["name"], bday, age + 1))

        except:

            continue


    upcoming.sort(key=lambda x: x[0])


    print("\n" + "="*52)

    print("  UPCOMING BIRTHDAYS")

    print("="*52)


    if not upcoming:

        print("  No birthdays found. Add birthdays when creating contacts.")

        return


    for days, name, bday, age in upcoming[:15]:

        if days == 0:

            when = "TODAY!"

        elif days == 1:

            when = "Tomorrow"

        elif days <= 7:

            when = f"In {days} days"

        elif days <= 30:

            when = f"In {days} days"

        else:

            when = f"In {days} days"


        print(f"  {when:<15} {name:<25} {bday}  (turns {age})")


    print("="*52)



# ============================================================

# EXPORT TO CSV

# ============================================================


def export_csv(data, filename=None):

    contacts = data["contacts"]

    if not contacts:

        print("  No contacts to export.")

        return


    if not filename:

        filename = f"contacts_export_{datetime.now().strftime('%Y%m%d_%H%M%S')}.csv"


    fields = ["name", "phone", "email", "company",

              "address", "birthday", "group", "notes"]


    with open(filename, "w", newline="", encoding="utf-8") as f:

        writer = csv.DictWriter(f, fieldnames=fields, extrasaction="ignore")

        writer.writeheader()

        for c in contacts:

            writer.writerow({k: c.get(k, "") for k in fields})


    print(f"\n  Exported {len(contacts)} contact(s) to: {filename}")



# ============================================================

# IMPORT FROM CSV

# ============================================================


def import_csv(data, filename):

    if not Path(filename).exists():

        print(f"  File not found: {filename}")

        return


    imported = 0

    skipped  = 0


    with open(filename, "r", encoding="utf-8", newline="") as f:

        reader = csv.DictReader(f)

        for row in reader:

            name = row.get("name", "").strip()

            if not name:

                skipped += 1

                continue


            # Skip if already exists

            if any(c["name"].lower() == name.lower()

                   for c in data["contacts"]):

                skipped += 1

                continue


            contact = {

                "id":         len(data["contacts"]) + 1,

                "name":       name,

                "phone":      row.get("phone", ""),

                "email":      row.get("email", ""),

                "address":    row.get("address", ""),

                "birthday":   row.get("birthday", ""),

                "company":    row.get("company", ""),

                "notes":      row.get("notes", ""),

                "group":      row.get("group", ""),

                "favourite":  False,

                "created_at": datetime.now().strftime("%d-%m-%Y %H:%M"),

                "updated_at": datetime.now().strftime("%d-%m-%Y %H:%M"),

            }

            data["contacts"].append(contact)


            # Add group

            if contact["group"] and contact["group"] not in data["groups"]:

                data["groups"].append(contact["group"])


            imported += 1


    save_contacts(data)

    print(f"\n  Imported: {imported}  |  Skipped (duplicate/empty): {skipped}")



# ============================================================

# GROUPS

# ============================================================


def manage_groups(data):

    print("\n" + "="*45)

    print("  GROUPS")

    print("="*45)


    if not data["groups"]:

        print("  No groups yet.")

    else:

        for i, g in enumerate(data["groups"], 1):

            count = sum(1 for c in data["contacts"]

                        if c.get("group") == g)

            print(f"  [{i}] {g}  ({count} contacts)")


    print("\n  1. View contacts in a group")

    print("  2. Rename a group")

    print("  3. Delete a group")

    print("  4. Back")


    sub = input("\n  > ").strip()


    if sub == "1":

        group = input("  Group name: ").strip()

        list_contacts(data, group_filter=group)


    elif sub == "2":

        old = input("  Current group name: ").strip()

        new = input("  New group name    : ").strip()

        if old and new:

            for c in data["contacts"]:

                if c.get("group") == old:

                    c["group"] = new

            if old in data["groups"]:

                data["groups"].remove(old)

            if new not in data["groups"]:

                data["groups"].append(new)

            save_contacts(data)

            print(f"  Renamed '{old}' to '{new}'")


    elif sub == "3":

        group = input("  Group to delete: ").strip()

        confirm = input(f"  Delete group '{group}'? Contacts will be ungrouped. (yes/no): ").strip().lower()

        if confirm == "yes":

            for c in data["contacts"]:

                if c.get("group") == group:

                    c["group"] = ""

            if group in data["groups"]:

                data["groups"].remove(group)

            save_contacts(data)

            print(f"  Group deleted: {group}")



# ============================================================

# STATS

# ============================================================


def show_stats(data):

    contacts = data["contacts"]

    total    = len(contacts)


    if not total:

        print("\n  No contacts yet.")

        return


    with_phone  = sum(1 for c in contacts if c.get("phone"))

    with_email  = sum(1 for c in contacts if c.get("email"))

    with_bday   = sum(1 for c in contacts if c.get("birthday"))

    favourites  = sum(1 for c in contacts if c.get("favourite"))


    group_counts = {}

    for c in contacts:

        g = c.get("group") or "Ungrouped"

        group_counts[g] = group_counts.get(g, 0) + 1


    print("\n" + "="*48)

    print("  CONTACT BOOK STATISTICS")

    print("="*48)

    print(f"  Total contacts  : {total}")

    print(f"  With phone      : {with_phone}")

    print(f"  With email      : {with_email}")

    print(f"  With birthday   : {with_bday}")

    print(f"  Favourites      : {favourites}")

    print(f"\n  By group:")

    for g, count in sorted(group_counts.items(), key=lambda x: -x[1]):

        bar = "█" * min(count, 20)

        print(f"  {g:<20} {count:>4}  {bar}")

    print("="*48)



# ============================================================

# SELECT CONTACT HELPER

# ============================================================


def select_contact(data, prompt="  Search contact: "):

    query = input(prompt).strip()

    if not query:

        return None

    results = search_contacts(data, query)

    if not results:

        return None

    if len(results) == 1:

        return results[0]

    try:

        idx = int(input("  Select number: ").strip()) - 1

        if 0 <= idx < len(results):

            return results[idx]

    except ValueError:

        pass

    return None



# ============================================================

# MAIN MENU

# ============================================================


def print_menu(data):

    total = len(data["contacts"])

    favs  = sum(1 for c in data["contacts"] if c.get("favourite"))

    print("\n" + "-"*50)

    print(f"  CONTACT BOOK  [{total} contacts  ★{favs} favourites]")

    print("-"*50)

    print("  1.  Add new contact")

    print("  2.  View all contacts")

    print("  3.  Search contact")

    print("  4.  View contact details")

    print("  5.  Edit contact")

    print("  6.  Delete contact")

    print("  7.  View favourites")

    print("  8.  Birthday reminders")

    print("  9.  Manage groups")

    print("  10. Export to CSV")

    print("  11. Import from CSV")

    print("  12. Statistics")

    print("  13. Backup contacts")

    print("  0.  Exit")

    print("-"*50)



def main():

    print("\n" + "="*55)

    print("     CONTACT BOOK MANAGER")

    print("="*55)


    data = load_contacts()

    if data["contacts"]:

        print(f"\n  Loaded {len(data['contacts'])} contact(s) from {DATA_FILE}")

    else:

        print("\n  No contacts yet. Start by adding one!")


    while True:

        print_menu(data)

        choice = input("  > ").strip()


        if choice == "1":

            add_contact(data)


        elif choice == "2":

            print("\n  Sort by: 1=Name  2=Company  3=Group  4=Recent")

            sort_opt = input("  Sort (default Name): ").strip()

            sort_map = {"1": "name", "2": "company",

                        "3": "group", "4": "recent"}

            sort_by  = sort_map.get(sort_opt, "name")

            list_contacts(data, sort_by=sort_by)


        elif choice == "3":

            query = input("\n  Search: ").strip()

            search_contacts(data, query)


        elif choice == "4":

            contact = select_contact(data)

            if contact:

                view_contact(contact)


        elif choice == "5":

            contact = select_contact(data)

            if contact:

                edit_contact(data, contact)


        elif choice == "6":

            contact = select_contact(data)

            if contact:

                view_contact(contact)

                delete_contact(data, contact)


        elif choice == "7":

            list_contacts(data, favourites_only=True)


        elif choice == "8":

            birthday_reminders(data)


        elif choice == "9":

            manage_groups(data)


        elif choice == "10":

            fname = input("  Output filename (Enter=auto): ").strip() or None

            export_csv(data, fname)


        elif choice == "11":

            fname = input("  CSV file path: ").strip()

            import_csv(data, fname)


        elif choice == "12":

            show_stats(data)


        elif choice == "13":

            backup_contacts(data)


        elif choice == "0":

            print("\n  Goodbye!\n")

            break


        else:

            print("  Invalid choice.")



# ============================================================

# RUN

# ============================================================


if __name__ == "__main__":

    main()