from flask import Flask, render_template, request, redirect, url_for
from urllib.parse import urlencode
import datetime
import json
import os

app = Flask(__name__)

# Parameter mapping for URL compression
PARAM_MAP = {
    # Long -> Short
    'title': 't',
    'target': 'dt',
    'scheme': 's', 
    'accent': 'a',
    'radius': 'r',
    'shadow': 'sh',
    'font': 'f',
    'millis': 'm',
    'rounded_unit': 'ru',
    'bg': 'bg',
    'fg': 'fg',
    'lang': 'l'
}

# Short -> Long (reverse mapping)
REVERSE_PARAM_MAP = {v: k for k, v in PARAM_MAP.items()}

def normalize_params(params_dict):
    """Convert short parameter names to long ones for internal use"""
    normalized = {}
    for key, value in params_dict.items():
        # Convert short to long if it exists in reverse map, otherwise keep original
        long_key = REVERSE_PARAM_MAP.get(key, key)
        normalized[long_key] = value
    return normalized

def compress_params(params_dict):
    """Convert long parameter names to short ones for URLs"""
    compressed = {}
    for key, value in params_dict.items():
        # Convert long to short if it exists in map, otherwise keep original
        short_key = PARAM_MAP.get(key, key)
        compressed[short_key] = value
    return compressed

def get_param(args, key, default=None):
    """Get parameter value checking both long and short names"""
    # Try long name first
    value = args.get(key, None)
    if value is not None:
        return value
    
    # Try short name
    short_key = PARAM_MAP.get(key)
    if short_key:
        value = args.get(short_key, None)
        if value is not None:
            return value
    
    return default

# Load translations
translations = {}
translations_dir = os.path.join(app.root_path, 'translations')
for filename in os.listdir(translations_dir):
    if filename.endswith('.json'):
        lang_code = filename[:-5]  # Remove .json extension
        with open(os.path.join(translations_dir, filename), 'r', encoding='utf-8') as f:
            translations[lang_code] = json.load(f)

def get_translation(lang, key, fallback_lang='en'):
    """Get translation for a key in specified language, fallback to English if not found"""
    keys = key.split('.')
    
    # Try specified language first
    current = translations.get(lang, {})
    for k in keys:
        if k in current:
            current = current[k]
        else:
            break
    else:
        return current
    
    # Fallback to English
    current = translations.get(fallback_lang, {})
    for k in keys:
        if k in current:
            current = current[k]
        else:
            return key  # Return key if not found
    return current

def coerce_bool(val, default=False):
    if val is None:
        return default
    s = str(val).lower()
    return s in ("1","true","yes","y","on")

@app.template_filter("default_if_none")
def default_if_none(value, default):
    return default if value is None or value == "" else value

@app.template_filter("translate")
def translate_filter(key, lang='en'):
    return get_translation(lang, key)

@app.template_filter("url_with_lang")
def url_with_lang_filter(query_string, new_lang):
    """Build clean URL with new language parameter using compressed format"""
    from urllib.parse import parse_qs, urlencode
    
    # Parse existing query string
    if query_string:
        params = parse_qs(query_string)
        # Flatten the parameters (parse_qs creates lists)
        flat_params = {k: v[0] if v else '' for k, v in params.items() if v}
        # Normalize to long parameter names first
        normalized = normalize_params(flat_params)
        # Remove any existing lang parameters
        normalized.pop('lang', None)
    else:
        normalized = {}
    
    # Add new language
    normalized['lang'] = new_lang
    
    # Convert back to compressed format
    compressed = compress_params(normalized)
    
    # Build clean query string
    return '?' + urlencode(compressed) if compressed else f'?{PARAM_MAP.get("lang", "lang")}={new_lang}'

@app.route("/")
def index():
    # Prefill from query if present, so users can tweak and regenerate
    q = request.args
    lang = get_param(q, "lang", "en")
    context = {
        "title": get_param(q, "title", get_translation(lang, "form.countdown_title_placeholder")),
        "target": get_param(q, "target", ""),
        "scheme": get_param(q, "scheme", "dark"),
        "accent": get_param(q, "accent", "#8b5cf6"),  # violet-500
        "radius": get_param(q, "radius", "16"),
        "shadow": get_param(q, "shadow", "lg"),
        "font": get_param(q, "font", "system-ui"),
        "show_millis": coerce_bool(get_param(q, "millis"), False),
        "rounded_unit": get_param(q, "rounded_unit", "none"),  # none, minutes, hours, days
        "bg": get_param(q, "bg", "#0b0b10"),
        "fg": get_param(q, "fg", "#e5e7eb"),
        "lang": lang,
        "t": lambda key: get_translation(lang, key)
    }
    return render_template("index.html", **context)

@app.route("/preview", methods=["POST"])
def preview():
    data = request.form.to_dict(flat=True)
    # Convert to compressed parameters
    compressed_data = compress_params(data)
    # Build query string and redirect to /countdown
    return redirect(url_for("countdown") + "?" + urlencode(compressed_data))

@app.route("/countdown")
def countdown():
    q = request.args
    lang = get_param(q, "lang", "en")
    # Provide sane defaults if not supplied
    params = {
        "title": get_param(q, "title", get_translation(lang, "form.countdown_title_placeholder")),
        "target": get_param(q, "target", ""),
        "scheme": get_param(q, "scheme", "dark"),
        "accent": get_param(q, "accent", "#8b5cf6"),
        "radius": get_param(q, "radius", "16"),
        "shadow": get_param(q, "shadow", "lg"),
        "font": get_param(q, "font", "system-ui"),
        "millis": get_param(q, "millis", "0"),
        "rounded_unit": get_param(q, "rounded_unit", "none"),
        "bg": get_param(q, "bg", "#0b0b10"),
        "fg": get_param(q, "fg", "#e5e7eb"),
        "lang": lang,
        "t": lambda key: get_translation(lang, key)
    }
    # If no target specified, bounce user to setup screen
    if not params["target"]:
        # Pass lang as short parameter when redirecting
        lang_param = PARAM_MAP.get("lang", "lang")
        return redirect(url_for("index") + f"?{lang_param}={lang}")
    return render_template("countdown.html", **params)

if __name__ == "__main__":
    # Helpful for local dev
    app.run(debug=True, host="0.0.0.0", port=5000)