import base64
import os
from urllib import request
from pathlib import Path

import streamlit as st


def _icon_data_uri(filename: str) -> str:
    icon_path = Path(__file__).resolve().parent.parent / "icons" / filename
    if not icon_path.exists():
        return ""
    try:
        encoded = base64.b64encode(icon_path.read_bytes()).decode("ascii")
    except Exception:
        return ""
    return f"data:image/png;base64,{encoded}"


def _build_sidebar_icon_css() -> str:
    """Use named icons for sidebar items: home/prob/batch/molecule/manual/ai."""
    fallback = {
        1: "🏠",
        2: "🔎",
        3: "📦",
        4: "🧬",
        5: "⚙️",
        6: "🧠",
        7: "✨",
        8: "💬",
    }
    icon_name = {
        1: "home1.png",
        2: "probe1.png",
        3: "batch1.png",
        4: "molecule1.png",
        5: "manual1.png",
        6: "ai1.png",
        7: "rnn1.png",
        8: "feedback.png",
    }
    rules = [
        '[data-testid="stSidebarNav"] ul li a { position: relative; padding-left: 3.9rem !important; }',
        '[data-testid="stSidebarNav"] ul li a::before { content: ""; position: absolute; left: 10px; top: 50%; transform: translateY(-50%); width: 46px; height: 46px; background-size: contain; background-repeat: no-repeat; background-position: center; }',
    ]
    for idx in range(1, 9):
        uri = _icon_data_uri(icon_name[idx])
        if uri:
            rules.append(
                '[data-testid="stSidebarNav"] ul li:nth-of-type(%d) a::before { content: ""; background-image: url("%s"); }'
                % (idx, uri)
            )
        else:
            emoji = fallback[idx]
            rules.append(
                '[data-testid="stSidebarNav"] ul li:nth-of-type(%d) a::before { content: "%s "; background-image: none; width: auto; height: auto; }'
                % (idx, emoji)
            )
    return "\n".join(rules)


def _log_visit_once_per_session() -> None:
    if st.session_state.get("_visit_logged"):
        return
    webhook_url = os.getenv("FEEDBACK_WEBHOOK_URL", "").strip()
    webhook_token = os.getenv("FEEDBACK_WEBHOOK_TOKEN", "").strip()
    if not webhook_url:
        return
    endpoint = webhook_url
    sep = "&" if "?" in webhook_url else "?"
    endpoint = f"{webhook_url}{sep}event=visit"
    if webhook_token:
        endpoint = f"{endpoint}&token={webhook_token}"
    try:
        with request.urlopen(endpoint, timeout=10):
            pass
    except Exception:
        pass
    st.session_state["_visit_logged"] = True


def apply_global_style() -> None:
    _log_visit_once_per_session()
    icon_css = _build_sidebar_icon_css()

    css = """
    <style>
    [data-testid="stSidebarNav"] ul li a {
        font-size: 1.2rem !important;
        font-weight: 600 !important;
        border-radius: 12px !important;
        padding: 0.42rem 0.65rem !important;
        margin-bottom: 0.38rem !important;
    }

    [data-testid="stSidebarNav"] ul li a span {
        font-size: 1.2rem !important;
        font-weight: 600 !important;
    }

    [data-testid="stSidebarNav"] ul li a[aria-current="page"] {
        background-color: rgba(44, 123, 29, 0.24) !important;
    }

    [data-testid="stSidebarNav"] ul li a[aria-current="page"] span {
        color: #1f3f7a !important;
        font-weight: 700 !important;
    }

    __ICON_CSS__
    </style>
    """
    st.markdown(css.replace("__ICON_CSS__", icon_css), unsafe_allow_html=True)