"""
app.py
------
Dash app 進入點。

職責（僅此而已）：
    1. 建立 Dash app 實例
    2. 組裝 AppShell layout
    3. 掛載全域 callback（navbar、主題、MathJax）
    4. 啟動 dev server

Build pipeline（MD → JSON）已移至 build.py。
  - 若希望每次啟動都重建：取消下方 build_if_needed 的 force=True 呼叫
  - 若只想手動重建：直接執行 python build.py --force
"""

import dash
from dash import Dash, html, dcc
from dash import Input, Output, clientside_callback
import dash_mantine_components as dmc
from pathlib import Path

from layout.shell.navbar    import generate_navbar
from layout.shell.header    import generate_header
from layout.shell.main      import generate_main
from layout.shell.footer    import generate_footer
from layout.shell.callbacks import generate_toggle_navbar, switch_light_dark

# 確保頁面 section 切換 callback 在啟動時就被註冊
import layout.page.page_callbacks  # noqa: F401

# 學生登入元件
from student_login import create_student_store, create_login_modal, create_student_badge

# Firebase quiz hooks（答題記錄）
from firebase_quiz_hooks import create_dummy_stores
import firebase_quiz_hooks  # noqa: F401 ← 掛載 callback

# Session 狀態保存（重整後恢復 section、答題、解法）由 assets/session_state.js 處理
from session_state import create_session_stores

# Build pipeline：只在啟動時呼叫，不影響 app 本體邏輯
from build import build_if_needed

BASE_DIR    = Path(__file__).resolve().parent
CONFIG_PATH = BASE_DIR / "paths.json"

import os
if not os.getenv("SPACE_ID"):  # 不在 HF 上才 build
    build_if_needed(CONFIG_PATH, force=False)

# ---------------------------------------------------------------------------
# App 實例
# ---------------------------------------------------------------------------
app = Dash(
    __name__,
    use_pages=True,
    external_stylesheets=dmc.styles.ALL,
    suppress_callback_exceptions=True,
)

# ---------------------------------------------------------------------------
# Callbacks
# ---------------------------------------------------------------------------
generate_toggle_navbar()
switch_light_dark()

# ---------------------------------------------------------------------------
# Layout 元件
# ---------------------------------------------------------------------------
header = generate_header()
navbar = generate_navbar()
main   = generate_main()
footer = generate_footer()

layout = dmc.AppShell(
    id="appshell",
    children=[
        dcc.Store(id="noop-store"),
        html.Div(id="theme-dummy", style={"display": "none"}),

        # ── 學生登入相關 ──
        create_student_store(),       # localStorage 學號 Store
        create_login_modal(),         # 學號輸入 Modal
        *create_dummy_stores(),       # Firebase 虛擬 Store
        *create_session_stores(),     # Session 狀態 Store

        header, navbar, main, footer,
    ],
    header={"height": "4rem"},
    navbar={
        "width": {"xs": 200, "sm": 250, "md": 300, "lg": 300},
        "breakpoint": "sm",
        "collapsed": {"mobile": True, "desktop": False},
    },
    footer={"height": "2rem"},
    padding="lg",
)

app.layout = dmc.MantineProvider(
    id="mantine-provider",
    children=layout,
    defaultColorScheme="light",
)

# ---------------------------------------------------------------------------
# MathJax：每次換頁都重新 typeset
# ---------------------------------------------------------------------------
clientside_callback(
    """
    function(pathname) {
        if (window.MathJax) {
            window.MathJax.typeset();
        }
        return "";
    }
    """,
    Output("noop-store", "data"),
    Input("_pages_location", "pathname"),
)

# ---------------------------------------------------------------------------
# 啟動
# ---------------------------------------------------------------------------
server = app.server  # 給 gunicorn 用：gunicorn app:server

if __name__ == "__main__":
    # app.run(debug=True)
    # 部署時改用：
    app.run(host="0.0.0.0", port=7860, debug=False)