from flask import Blueprint, Response, render_template, jsonify, url_for
from jinja2 import TemplateNotFound
from html.parser import HTMLParser
import json
import logging
import re
from pathlib import Path

# Strict allowlists for URL-derived values used in path and script operations.
_SAFE_PLUGIN_ID_RE = re.compile(r'^[a-zA-Z0-9_-]{1,64}$')
_SAFE_WEB_UI_FILE_RE = re.compile(r'^[a-zA-Z0-9_-]{1,64}\.html$')
_SAFE_WIDGET_NAME_RE = re.compile(r'^[a-zA-Z0-9_-]{1,64}$')
_SAFE_WIDGET_SCRIPT_RE = re.compile(r'^[a-zA-Z0-9_-]{1,64}\.js$')
from src.web_interface.secret_helpers import mask_secret_fields
from src.plugin_system.schema_manager import plugin_config_defaults, prepare_plugin_config
from src.common.path_safety import resolve_under, safe_path_component
from src.pi5_matrix_support import is_raspberry_pi_5
from web_interface import widget_bundle

logger = logging.getLogger(__name__)

# The managers live on the blueprint object: app.py sets
# pages_v3.config_manager, pages_v3.plugin_manager and the rest.
pages_v3 = Blueprint('pages_v3', __name__)


@pages_v3.route('/assets/widgets.js')
def widgets_bundle():
    """Every widget script in one request (see web_interface/widget_bundle.py).

    The individual files stay served from /static for plugin-loader.js and
    debugging; this saves the Pi ~30 round trips on each first page load.
    Cached as immutable by app.py because the URL carries the version.
    """
    body, version = widget_bundle.build_bundle()
    response = Response(body, mimetype='application/javascript')
    response.headers['X-Widget-Bundle-Version'] = str(version)
    return response


@pages_v3.app_context_processor
def inject_widget_bundle_url():
    """`widgets_bundle_url()` for templates, versioned by file mtime."""
    return {
        'widgets_bundle_url': lambda: url_for(
            'pages_v3.widgets_bundle', v=widget_bundle.bundle_version()
        )
    }


class _SettingsIndexParser(HTMLParser):
    """Extract searchable settings fields from a rendered partial's HTML.

    Captures one entry per ``<div class="form-group" id="setting-…">``: the
    anchor id, ``data-setting-key``, the field's ``<label>`` text, the
    ``.help-tip`` tooltip text (``data-tooltip``), and the nearest preceding
    ``<h3>``/``<h4>`` section heading. Parsing the *rendered* HTML (rather than
    the schema) guarantees the anchor ids match the live DOM exactly, so the
    search index cannot drift from what users actually see.
    """

    def __init__(self, tab, tab_label):
        super().__init__(convert_charrefs=True)
        self.tab = tab
        self.tab_label = tab_label
        self.fields = []
        self._section = ''
        self._field = None
        self._depth = 0            # open-div depth within the current field
        self._in_label = False
        self._label_parts = []
        self._in_heading = False
        self._heading_parts = []

    def handle_starttag(self, tag, attrs):
        a = {k: (v or '') for k, v in attrs}
        classes = a.get('class', '').split()
        # Section headings (only when not already inside a field)
        if tag in ('h3', 'h4') and self._field is None:
            self._in_heading = True
            self._heading_parts = []
        if tag == 'div':
            fid = a.get('id', '')
            if self._field is None and 'form-group' in classes and fid.startswith('setting-'):
                self._field = {
                    'anchorId': fid,
                    'key': a.get('data-setting-key', '') or fid[len('setting-'):],
                    'label': '',
                    'help': '',
                    'section': self._section,
                    'tab': self.tab,
                    'tabLabel': self.tab_label,
                }
                self._depth = 1
                return
            if self._field is not None:
                self._depth += 1
        if self._field is not None:
            if tag == 'label' and not self._field['label']:
                self._in_label = True
                self._label_parts = []
            if tag == 'button' and 'help-tip' in classes and not self._field['help']:
                self._field['help'] = a.get('data-tooltip', '')

    def handle_data(self, data):
        if self._in_label:
            self._label_parts.append(data)
        elif self._in_heading:
            self._heading_parts.append(data)

    def handle_endtag(self, tag):
        if tag in ('h3', 'h4') and self._in_heading:
            self._in_heading = False
            self._section = ' '.join(''.join(self._heading_parts).split()).strip()
            return
        if self._field is None:
            return
        if tag == 'label' and self._in_label:
            self._in_label = False
            self._field['label'] = ' '.join(''.join(self._label_parts).split()).strip()
        elif tag == 'div':
            self._depth -= 1
            if self._depth <= 0:
                if self._field['label']:
                    self.fields.append(self._field)
                self._field = None
                self._depth = 0


def _partial_html(loader):
    """Run a partial loader and return its HTML string ('' on error)."""
    try:
        result = loader()
    except Exception:
        logger.warning("search-index: partial render failed", exc_info=True)
        return ''
    if isinstance(result, str):
        return result
    if isinstance(result, tuple):  # loaders return (msg, status) on error
        return ''
    try:
        return result.get_data(as_text=True)
    except Exception:
        return ''


def _extract_settings_fields(html, tab, tab_label):
    parser = _SettingsIndexParser(tab, tab_label)
    parser.feed(html)
    return parser.fields


# Cache the built index keyed on the installed-plugin set. Core labels/tooltips
# are static template text, so only a change in installed plugins invalidates it.
_SEARCH_INDEX_CACHE = {'sig': None, 'fields': None}


@pages_v3.route('/')
def index():
    """Main v3 interface page: the app shell. Every tab loads as a partial."""
    return render_template('v3/base.html')

@pages_v3.route('/partials/<partial_name>')
def load_partial(partial_name):
    """One tab's HTML for HTMX, by the names in _PARTIAL_LOADERS; 404 otherwise."""
    loader = _PARTIAL_LOADERS.get(partial_name)
    if loader is None:
        return "Partial not found", 404
    try:
        return loader()
    except Exception:
        logger.error("Error loading partial %s", partial_name, exc_info=True)
        return "Error loading partial", 500


@pages_v3.route('/partials/plugin-config/<plugin_id>')
def load_plugin_config_partial(plugin_id):
    """Load plugin configuration partial via HTMX - server-side rendered form"""
    try:
        return _load_plugin_config_partial(plugin_id)
    except Exception:
        logger.error("Error loading plugin config partial for %s", plugin_id, exc_info=True)
        return '<div class="text-red-500 p-4">Error loading plugin config; see logs for details</div>', 500


@pages_v3.route('/settings/search-index')
def settings_search_index():
    """Return a flat JSON index of every searchable setting (core + plugin).

    Powers the web UI's global settings search. Built by rendering the settings
    partials server-side and extracting field metadata, then cached per
    installed-plugin set so it is off the display's hot path.
    """
    # Core settings tabs: (activeTab value, human label, loader).
    core_tabs = [
        ('general', 'General', _load_general_partial),
        ('display', 'Display', _load_display_partial),
        ('durations', 'Durations', _load_durations_partial),
        ('schedule', 'Schedule', _load_schedule_partial),
        ('wifi', 'WiFi', _load_wifi_partial),
    ]
    try:
        plugin_ids = []
        if pages_v3.plugin_manager:
            try:
                pages_v3.plugin_manager.discover_plugins()
                plugin_ids = sorted(
                    pi.get('id') for pi in pages_v3.plugin_manager.get_all_plugin_info()
                    if pi.get('id')
                )
            except Exception:
                logger.warning("search-index: could not enumerate plugins", exc_info=True)

        sig = tuple(plugin_ids)
        if _SEARCH_INDEX_CACHE['sig'] == sig and _SEARCH_INDEX_CACHE['fields'] is not None:
            return jsonify({'fields': _SEARCH_INDEX_CACHE['fields']})

        fields = []
        for tab, label, loader in core_tabs:
            fields.extend(_extract_settings_fields(_partial_html(loader), tab, label))

        for pid in plugin_ids:
            info = pages_v3.plugin_manager.get_plugin_info(pid) or {}
            label = info.get('name', pid)
            html = _partial_html(lambda pid=pid: _load_plugin_config_partial(pid))
            fields.extend(_extract_settings_fields(html, pid, label))

        _SEARCH_INDEX_CACHE['sig'] = sig
        _SEARCH_INDEX_CACHE['fields'] = fields
        return jsonify({'fields': fields})
    except Exception:
        logger.error("Error building settings search index", exc_info=True)
        return jsonify({'fields': []}), 500


@pages_v3.route('/plugin-ui/<plugin_id>/web-ui/<path:filename>')
def serve_plugin_web_ui(plugin_id, filename):
    """Serve a plugin's web_ui/ HTML fragment as a standalone page.

    Wraps the fragment with a minimal HTML page that injects window.PLUGIN_ID
    and loads Tailwind CSS so the fragment runs correctly inside the iframe
    that plugin_config.html embeds it in.

    That iframe carries no ``sandbox`` attribute, so the fragment runs with
    the interface's own origin. That is deliberate rather than an oversight:
    the fragment is a file from an installed plugin, and an installed plugin
    already runs Python on the device. The trust boundary is plugin install,
    not this route. It is worth knowing when reading the code, which is why
    it says so here instead of claiming a sandbox that is not there.
    """
    # Validate URL-derived values against strict allowlists before any path or
    # script operations.
    if not _SAFE_PLUGIN_ID_RE.match(plugin_id):
        return 'Invalid plugin ID', 400, {'Content-Type': 'text/plain'}
    if not _SAFE_WEB_UI_FILE_RE.match(filename):
        return 'Invalid filename', 400, {'Content-Type': 'text/plain'}

    # The allowlists above already forbid a separator, but the value that gets
    # joined has to be the checked one, not the argument -- see
    # src/common/path_safety.py. safe_path_component rejects rather than
    # truncates, so these cannot disagree.
    safe_id = safe_path_component(plugin_id)
    safe_fn = safe_path_component(filename)
    if not safe_id or not safe_fn:
        return 'Invalid path component', 400, {'Content-Type': 'text/plain'}

    if not pages_v3.plugin_manager:
        return 'Plugin manager not available', 503, {'Content-Type': 'text/plain'}

    try:
        web_ui_path = resolve_under(_plugin_dir_for(safe_id) / 'web_ui', safe_fn)
        if web_ui_path is None:
            return 'Forbidden', 403, {'Content-Type': 'text/plain'}

        if not web_ui_path.exists():
            return 'Not found', 404, {'Content-Type': 'text/plain'}

        fragment = web_ui_path.read_text(encoding='utf-8')

        # json.dumps wraps the value in quotes.  Replace HTML meta-chars with
        # their JS Unicode escape sequences so the value cannot close or escape
        # the enclosing <script> tag.
        # r'<' is the 6-char literal string <, which JavaScript
        # interprets as <.  This is the standard JSON-in-HTML hardening pattern.
        safe_plugin_id_js = (
            json.dumps(safe_id)
            .replace('<', '\\u003c')
            .replace('>', '\\u003e')
            .replace('&', '\\u0026')
        )

        page = (
            '<!DOCTYPE html>\n'
            '<html lang="en">\n'
            '<head>\n'
            '<meta charset="UTF-8">\n'
            '<meta name="viewport" content="width=device-width,initial-scale=1">\n'
            '<script>\n'
            # Inject plugin context before the fragment runs.
            # plugin_id is validated to [a-zA-Z0-9_-] above, so this is safe,
            # but we also Unicode-escape HTML meta-chars as defence in depth.
            f'  window.PLUGIN_ID = {safe_plugin_id_js};\n'
            '</script>\n'
            # Tailwind v2 CDN — same version used by the parent LEDMatrix UI
            '<link rel="stylesheet" '
            'href="https://cdnjs.cloudflare.com/ajax/libs/tailwindcss/2.2.19/tailwind.min.css" '
            'crossorigin="anonymous">\n'
            '<style>body{margin:0;padding:0;background:#fff;}</style>\n'
            '</head>\n'
            '<body>\n'
            + fragment +
            '\n</body>\n</html>'
        )
        return page, 200, {'Content-Type': 'text/html; charset=utf-8'}

    except ValueError:
        return 'Forbidden', 403, {'Content-Type': 'text/plain'}
    except Exception:
        logger.error('Error serving plugin web_ui %s/%s', plugin_id, filename, exc_info=True)
        return 'Error serving file', 500, {'Content-Type': 'text/plain'}


def _resolved_plugin_dir(plugin_id):
    """The plugin manager's answer for where ``plugin_id`` lives, or None.

    Its discovery map is authoritative (a plugin whose directory name is not
    its id is found there), and it refuses anything that is not one plain
    path segment. See src/plugin_system/plugin_dirs.py.
    """
    found = pages_v3.plugin_manager.get_plugin_directory(plugin_id)
    if isinstance(found, (str, Path)) and Path(found).exists():
        return Path(found)
    return None


def _plugin_dir_for(safe_id):
    """A sanitised plugin id's directory, which may not exist.

    The plugin manager's resolver first; otherwise contained under the
    configured plugins directory, with PluginManager's ``ledmatrix-`` prefix
    fallback. Raises ValueError for an id that would leave it; the routes
    answer that with a 403.
    """
    resolved = _resolved_plugin_dir(safe_id)
    if resolved is not None:
        return resolved

    plugins_base = Path(pages_v3.plugin_manager.plugins_dir).resolve()
    plugin_dir = resolve_under(plugins_base, safe_id)
    if plugin_dir is None:
        raise ValueError('plugin id escapes the plugins directory')

    if not plugin_dir.exists():
        alt = resolve_under(plugins_base, f'ledmatrix-{safe_id}')
        if alt is not None:
            plugin_dir = alt
    return plugin_dir


def _declared_widget_script(plugin_dir, widget_name):
    """The script filename a plugin's manifest declares for ``widget_name``.

    The manifest is the allowlist: only a widget the plugin actually declares
    can be served, so this route never exposes arbitrary files under the
    plugin directory even though the directory itself is attacker-influenced
    (plugins are user-installed). Returns None when the widget is not
    declared, the manifest is unreadable, or the declared script name is not
    a plain ``<name>.js`` basename.
    """
    manifest_path = plugin_dir / 'manifest.json'
    try:
        with open(manifest_path, 'r', encoding='utf-8') as f:
            manifest = json.load(f)
    except (OSError, ValueError):
        return None
    if not isinstance(manifest, dict):
        return None

    for entry in manifest.get('widgets') or ():
        if not isinstance(entry, dict):
            continue
        if entry.get('name') != widget_name:
            continue
        script = entry.get('script') or f'{widget_name}.js'
        if not isinstance(script, str) or not _SAFE_WIDGET_SCRIPT_RE.match(script):
            return None
        return script
    return None


@pages_v3.route('/static/plugin-widgets/<plugin_id>/<widget_name>.js')
def serve_plugin_widget(plugin_id, widget_name):
    """Serve a plugin-declared widget script from its ``widgets/`` directory.

    This is the server half of ``LEDMatrixWidgets.loadPluginWidget`` (see
    static/v3/js/widgets/plugin-loader.js), which fetches exactly this path.
    The loader uses a dynamic ``import()``, so the response must carry a
    JavaScript MIME type or the browser refuses the module.

    The route is deliberately narrower than the plugin directory: a script is
    served only when the plugin's own manifest declares a widget by that name,
    so installing a plugin does not publish everything it ships.
    """
    if not _SAFE_PLUGIN_ID_RE.match(plugin_id):
        return 'Invalid plugin ID', 400, {'Content-Type': 'text/plain'}
    if not _SAFE_WIDGET_NAME_RE.match(widget_name):
        return 'Invalid widget name', 400, {'Content-Type': 'text/plain'}

    # safe_path_component is this codebase's sanitiser (src/common/
    # path_safety.py): it rejects rather than mangles, so a name that is not
    # a plain path component never reaches the filesystem.
    safe_id = safe_path_component(plugin_id)
    safe_widget = safe_path_component(widget_name)
    if not safe_id or not safe_widget:
        return 'Invalid path component', 400, {'Content-Type': 'text/plain'}

    if not pages_v3.plugin_manager:
        return 'Plugin manager not available', 503, {'Content-Type': 'text/plain'}

    try:
        plugin_dir = _plugin_dir_for(safe_id)
        if not plugin_dir.exists():
            return 'Not found', 404, {'Content-Type': 'text/plain'}

        script = _declared_widget_script(plugin_dir, safe_widget)
        if script is None:
            # Undeclared is a 404 rather than a 403: whether a plugin happens
            # to ship an undeclared file is not something to confirm.
            return 'Not found', 404, {'Content-Type': 'text/plain'}

        # Contain widgets/ itself first: a symlinked widgets directory would
        # otherwise become the base the script is checked against.
        widgets_dir = resolve_under(plugin_dir, 'widgets')
        if widgets_dir is None:
            return 'Not found', 404, {'Content-Type': 'text/plain'}
        # The script name comes from the plugin's manifest, not the request,
        # so it gets the same containment treatment the URL parts got.
        script_path = resolve_under(widgets_dir, script)
        if script_path is None or not script_path.is_file():
            return 'Not found', 404, {'Content-Type': 'text/plain'}

        body = script_path.read_text(encoding='utf-8')
        return body, 200, {
            'Content-Type': 'text/javascript; charset=utf-8',
            # Plugin updates replace this file in place; revalidate so a
            # stale widget cannot outlive the plugin version that shipped it.
            'Cache-Control': 'no-cache',
        }

    except ValueError:
        return 'Forbidden', 403, {'Content-Type': 'text/plain'}
    except Exception:
        logger.error('Error serving plugin widget %s/%s', plugin_id, widget_name,
                     exc_info=True)
        return 'Error serving file', 500, {'Content-Type': 'text/plain'}


def _load_overview_partial():
    """Load overview partial with system stats"""
    if pages_v3.config_manager:
        main_config = pages_v3.config_manager.load_config()
        # This would be populated with real system stats via SSE
        return render_template('v3/partials/overview.html',
                             main_config=main_config)

def _load_general_partial():
    """Load general settings partial"""
    if pages_v3.config_manager:
        main_config = pages_v3.config_manager.load_config()
        try:
            from web_interface.auto_update import describe_status
            auto_update_status = describe_status(main_config)
        except Exception:
            logger.debug("Could not read auto-update status", exc_info=True)
            auto_update_status = None
        return render_template('v3/partials/general.html',
                             main_config=main_config,
                             auto_update_status=auto_update_status,
                             web_login=_web_login_state())


def _web_login_state():
    """What the General tab's Security section shows; None hides it.

    None when the app has no login store (a bare test app), so the section
    only appears where it can work. Never includes a hash.
    """
    from web_interface import auth as web_auth
    store = web_auth.get_store()
    if store is None:
        return None
    return {
        'enabled': store.is_enabled(),
        'tokens': store.list_tokens(),
        'min_length': web_auth.MIN_PASSWORD_LENGTH,
    }

def _load_display_partial():
    """Load display settings partial"""
    if pages_v3.config_manager:
        main_config = pages_v3.config_manager.load_config()
        return render_template('v3/partials/display.html',
                             main_config=main_config,
                             is_pi5=is_raspberry_pi_5())

def _plugin_default_duration(plugin_id, plugin_config):
    """Seconds a plugin shows each screen when the Rotation page sets none.

    Mirrors BasePlugin.get_display_duration's config fallback: the plugin's
    display_duration, else its schema default, else 15.
    """
    def _valid(v):
        return isinstance(v, (int, float)) and not isinstance(v, bool) and v > 0

    value = plugin_config.get('display_duration')
    if not _valid(value):
        schema = None
        schema_mgr = getattr(pages_v3, 'schema_manager', None)
        if schema_mgr is not None:
            try:
                schema = schema_mgr.load_schema(plugin_id)
            except Exception:
                logger.debug("durations: no schema for %s", plugin_id, exc_info=True)
        value = plugin_config_defaults(schema if isinstance(schema, dict) else None).get(
            'display_duration')
        if not _valid(value):
            value = 15
    return int(value) if float(value).is_integer() else value


def _load_durations_partial():
    """Load rotation & durations partial.

    Builds one duration entry per display mode of every enabled plugin. A mode
    with a value saved in display.display_durations shows it; the rest are
    blank, with the plugin's own duration as the placeholder, because a saved
    value overrides the plugin (see DisplayController._get_display_duration).
    Pre-filling every mode would pin them all on the first save.
    """
    if pages_v3.config_manager:
        main_config = pages_v3.config_manager.load_config()
        duration_groups = []
        covered_keys = set()
        if pages_v3.plugin_manager:
            try:
                pages_v3.plugin_manager.discover_plugins()
                saved = (main_config.get('display', {}) or {}).get('display_durations', {}) or {}
                infos = sorted(pages_v3.plugin_manager.get_all_plugin_info(),
                               key=lambda i: (i.get('name') or i.get('id') or '').lower())
                for info in infos:
                    pid = info.get('id')
                    if not pid or not (main_config.get(pid, {}) or {}).get('enabled', False):
                        continue
                    modes = pages_v3.plugin_manager.get_plugin_display_modes(pid) or [pid]
                    covered_keys.update(modes)
                    default = _plugin_default_duration(pid, main_config.get(pid, {}) or {})
                    duration_groups.append({
                        'plugin_id': pid,
                        'plugin_name': info.get('name') or pid,
                        'modes': [{'key': m, 'value': saved.get(m, ''), 'default': default}
                                  for m in modes],
                    })
                # Saved keys not owned by any enabled plugin (disabled or
                # uninstalled plugins) stay visible rather than vanishing.
                leftovers = [{'key': k, 'value': v} for k, v in saved.items()
                             if k not in covered_keys]
                if leftovers:
                    duration_groups.append({
                        'plugin_id': '',
                        'plugin_name': 'Other saved entries',
                        'modes': leftovers,
                    })
            except Exception:
                logger.warning("durations: could not enumerate plugin modes", exc_info=True)
        return render_template('v3/partials/durations.html',
                             main_config=main_config,
                             duration_groups=duration_groups)

def _load_schedule_partial():
    """Load schedule settings partial"""
    if pages_v3.config_manager:
        main_config = pages_v3.config_manager.load_config()
        schedule_config = main_config.get('schedule', {})
        dim_schedule_config = main_config.get('dim_schedule', {})
        # Get normal brightness for display in dim schedule UI
        normal_brightness = main_config.get('display', {}).get('hardware', {}).get('brightness', 90)
        return render_template('v3/partials/schedule.html',
                             schedule_config=schedule_config,
                             dim_schedule_config=dim_schedule_config,
                             normal_brightness=normal_brightness)


def _load_plugins_partial():
    """Load plugins management partial"""
    # plugins.html takes no plugin data: plugins_manager.js fetches the list
    # from /api/v3/plugins/installed. Building it here read every manifest on
    # disk on each Plugins-tab load for nothing.
    return render_template('v3/partials/plugins.html')

def _load_fonts_partial():
    """Load fonts management partial"""
    # The page fetches its font data from /api/v3/fonts/* itself.
    return render_template('v3/partials/fonts.html')

def _load_logs_partial():
    """Load logs viewer partial"""
    return render_template('v3/partials/logs.html')

def _load_raw_json_partial():
    """Load raw JSON editor partial"""
    if pages_v3.config_manager:
        main_config_data = pages_v3.config_manager.get_raw_file_content('main')
        # The web login section (password and token hashes) is managed in
        # General > Security, never in this editor; its save keeps it.
        from web_interface.auth import strip_auth_section
        secrets_config_data = strip_auth_section(
            pages_v3.config_manager.get_raw_file_content('secrets'))
        main_config_json = json.dumps(main_config_data, indent=4)
        secrets_config_json = json.dumps(secrets_config_data, indent=4)

        return render_template('v3/partials/raw_json.html',
                             main_config_json=main_config_json,
                             secrets_config_json=secrets_config_json,
                             main_config_path=pages_v3.config_manager.get_config_path(),
                             secrets_config_path=pages_v3.config_manager.get_secrets_path())

def _load_backup_restore_partial():
    """Load backup & restore partial."""
    return render_template('v3/partials/backup_restore.html')

@pages_v3.route('/setup')
def captive_setup():
    """Lightweight captive portal setup page — self-contained, no frameworks."""
    return render_template('v3/captive_setup.html')

def _load_wifi_partial():
    """Load WiFi setup partial"""
    return render_template('v3/partials/wifi.html')

def _load_cache_partial():
    """Load cache management partial"""
    return render_template('v3/partials/cache.html')

def _load_operation_history_partial():
    """Load operation history partial"""
    return render_template('v3/partials/operation_history.html')


def _load_tools_partial():
    """Load tools/utilities partial."""
    try:
        return render_template('v3/partials/tools.html')
    except TemplateNotFound:
        logger.error("[Pages V3][Tools] Template not found: v3/partials/tools.html", exc_info=True)
        return "[Pages V3][Tools] Template is missing.", 500
    except OSError as exc:
        logger.error("[Pages V3][Tools] I/O error loading tools partial: %s", exc, exc_info=True)
        return "[Pages V3][Tools] Failed to load due to a file system error. Check logs.", 500


_PARTIAL_LOADERS = {
    'overview': _load_overview_partial,
    'general': _load_general_partial,
    'display': _load_display_partial,
    'durations': _load_durations_partial,
    'schedule': _load_schedule_partial,
    'plugins': _load_plugins_partial,
    'fonts': _load_fonts_partial,
    'logs': _load_logs_partial,
    'raw-json': _load_raw_json_partial,
    'backup-restore': _load_backup_restore_partial,
    'wifi': _load_wifi_partial,
    'cache': _load_cache_partial,
    'operation-history': _load_operation_history_partial,
    'tools': _load_tools_partial,
}


def _load_plugin_config_partial(plugin_id):
    """
    Load plugin configuration partial - server-side rendered form.
    This replaces the client-side generateConfigForm() JavaScript.
    """
    # Refuse an id that is not a plain directory name, rather than quietly
    # basename-ing it down to one: "../weather" used to become "weather" and
    # render a partial the caller never asked for.
    plugin_id = safe_path_component(plugin_id)
    if not plugin_id or not re.match(r'^[a-zA-Z0-9][a-zA-Z0-9._\-:]*$', plugin_id):
        return '<div class="text-red-500 p-4">Invalid plugin ID</div>', 400

    try:
        if not pages_v3.plugin_manager:
            return '<div class="text-red-500 p-4">Plugin manager not available</div>', 500

        # Handle starlark app config (starlark:<app_id>)
        if plugin_id.startswith('starlark:'):
            return _load_starlark_config_partial(plugin_id[len('starlark:'):])

        # Resolve and validate all plugin paths against the plugins base directory
        _plugins_base = Path(pages_v3.plugin_manager.plugins_dir).resolve()
        _plugin_dir = resolve_under(_plugins_base, plugin_id)
        if _plugin_dir is None:
            return '<div class="text-red-500 p-4">Invalid plugin ID</div>', 400

        # Try to get plugin info first
        plugin_info = pages_v3.plugin_manager.get_plugin_info(plugin_id)

        # If not found, re-discover plugins (handles plugins added after startup)
        if not plugin_info:
            pages_v3.plugin_manager.discover_plugins()
            plugin_info = pages_v3.plugin_manager.get_plugin_info(plugin_id)

        if not plugin_info:
            return '<div class="text-red-500 p-4">Plugin not found</div>', 404

        # The containment check above only validates the id. The files are
        # read from wherever the plugin manager says the plugin lives, which
        # for one installed as ledmatrix-<id> is not plugins_dir/<id>.
        _plugin_dir = _resolved_plugin_dir(plugin_id) or _plugin_dir

        # Get plugin instance (may be None if not loaded)
        plugin_instance = pages_v3.plugin_manager.get_plugin(plugin_id)

        # Get plugin configuration from config file
        config = {}
        if pages_v3.config_manager:
            full_config = pages_v3.config_manager.load_config()
            config = full_config.get(plugin_id, {})

        # Load uploaded images from metadata file if images field exists in schema
        schema_path_temp = resolve_under(_plugin_dir, "config_schema.json")
        if schema_path_temp is not None and schema_path_temp.exists():
            try:
                with open(schema_path_temp, 'r', encoding='utf-8') as f:
                    temp_schema = json.load(f)
                    if (temp_schema.get('properties', {}).get('images', {}).get('x-widget') == 'file-upload' or
                        temp_schema.get('properties', {}).get('images', {}).get('x_widget') == 'file-upload'):
                        _assets_base = (Path(__file__).parent.parent.parent / 'assets' / 'plugins').resolve()
                        metadata_file = resolve_under(
                            _assets_base, plugin_id, 'uploads', '.metadata.json'
                        )
                        if metadata_file and metadata_file.exists():
                            try:
                                with open(metadata_file, 'r', encoding='utf-8') as mf:
                                    metadata = json.load(mf)
                                    images_from_metadata = list(metadata.values())
                                    if not config.get('images') or len(config.get('images', [])) == 0:
                                        config['images'] = images_from_metadata
                                    else:
                                        config_image_ids = {img.get('id') for img in config.get('images', []) if img.get('id')}
                                        new_images = [img for img in images_from_metadata if img.get('id') not in config_image_ids]
                                        if new_images:
                                            config['images'] = config.get('images', []) + new_images
                            except Exception as e:
                                logger.warning("Could not load plugin upload metadata: %s", e)
            except Exception as e:  # nosec B110 - metadata pre-load is optional; schema loads fully below
                logger.debug("Metadata pre-load skipped for plugin %s: %s", plugin_id, e)

        # Get plugin schema.
        #
        # Through SchemaManager, not a raw json.load, because that is what
        # the save route uses (api_v3.save_plugin_config) -- and the two
        # disagreeing is not academic. SchemaManager applies
        # expand_style_elements, which turns a compact
        # customization.x-style-elements declaration into the per-element
        # blocks this form renders. Reading the file directly meant a plugin
        # using that form (of-the-day ships one) had a customization section
        # that rendered nothing at all, while saving still validated against
        # the expanded shape.
        #
        # use_cache=False matches the save route: a plugin's schema changes
        # on disk during development, and a cached copy would keep serving
        # the old form.
        #
        # The raw read stays as a fallback for callers that never set a
        # schema_manager (several tests, and any embedder of this blueprint).
        schema = {}
        schema_mgr = getattr(pages_v3, 'schema_manager', None)
        if schema_mgr is not None:
            try:
                schema = schema_mgr.load_schema(plugin_id, use_cache=False) or {}
            except Exception as e:
                logger.warning("SchemaManager could not load schema for %s: %s",
                               plugin_id, e)
        if not schema:
            # resolve_under keeps the containment guard main added here; the
            # SchemaManager path above does its own.
            schema_path = resolve_under(_plugin_dir, "config_schema.json")
            if schema_path is not None and schema_path.exists():
                try:
                    with open(schema_path, 'r', encoding='utf-8') as f:
                        schema = json.load(f)
                except Exception as e:
                    logger.warning("Could not load schema for plugin: %s", e)

        # Get web UI actions from plugin manifest
        web_ui_actions = []
        manifest_path = resolve_under(_plugin_dir, "manifest.json")
        if manifest_path is not None and manifest_path.exists():
            try:
                with open(manifest_path, 'r', encoding='utf-8') as f:
                    manifest = json.load(f)
                    web_ui_actions = manifest.get('web_ui_actions', [])
            except Exception as e:
                logger.warning("Could not load manifest for plugin: %s", e)
        
        schema_properties = schema.get('properties') if isinstance(schema, dict) else None
        if not isinstance(schema_properties, dict):
            return '<div class="text-red-500 p-4">Error loading plugin config securely: schema unavailable.</div>', 500

        # Fill in schema defaults for keys the saved config doesn't have yet,
        # as GET /api/v3/plugins/config does. Without this, an option added in
        # a plugin update (geochron 1.2.0's show_date, default true) renders
        # as an unchecked box, and because the save treats every drawn but
        # unposted checkbox as false, the first save turns it off for good.
        try:
            defaults = plugin_config_defaults(schema)
            if schema_mgr is not None:
                defaults = schema_mgr.apply_device_location(defaults)
            config = prepare_plugin_config(config, schema, defaults)
        except Exception as e:
            logger.warning("Could not merge schema defaults for %s: %s", plugin_id, e)

        # Mask secret fields before rendering template (fail closed — never
        # leak secrets). After the merge, so a secret's default is masked too.
        config = mask_secret_fields(config, schema_properties)

        # Determine enabled status
        enabled = config.get('enabled', True)
        if plugin_instance:
            enabled = plugin_instance.enabled

        # Build plugin data for template
        plugin_data = {
            'id': plugin_id,
            'name': plugin_info.get('name', plugin_id),
            'author': plugin_info.get('author', 'Unknown'),
            'version': plugin_info.get('version', ''),
            'description': plugin_info.get('description', ''),
            'category': plugin_info.get('category', 'General'),
            'tags': plugin_info.get('tags', []),
            'enabled': enabled,
            'last_commit': plugin_info.get('last_commit') or plugin_info.get('last_commit_sha', ''),
            'branch': plugin_info.get('branch', ''),
        }
        
        return render_template(
            'v3/partials/plugin_config.html',
            plugin=plugin_data,
            config=config,
            schema=schema,
            web_ui_actions=web_ui_actions
        )
        
    except Exception:
        logger.error("Error loading plugin config partial for %s", plugin_id, exc_info=True)
        return '<div class="text-red-500 p-4">Error loading plugin config; see logs for details</div>', 500


def _load_starlark_config_partial(app_id):
    """Load configuration partial for a Starlark app."""
    # Refuse an id that is not a plain directory name rather than basename-ing
    # it down to one -- see _load_plugin_config_partial for why.
    app_id = safe_path_component(app_id)
    if not app_id or not re.match(r'^[a-zA-Z0-9][a-zA-Z0-9_\-]*$', app_id):
        return '<div class="text-red-500 p-4">Invalid app ID</div>', 400

    try:
        starlark_plugin = pages_v3.plugin_manager.get_plugin('starlark-apps') if pages_v3.plugin_manager else None

        if starlark_plugin and hasattr(starlark_plugin, 'apps'):
            app = starlark_plugin.apps.get(app_id)
            if not app:
                return '<div class="text-red-500 p-4">Starlark app not found</div>', 404
            return render_template(
                'v3/partials/starlark_config.html',
                app_id=app_id,
                app_name=app.manifest.get('name', app_id),
                app_enabled=app.is_enabled(),
                render_interval=app.get_render_interval(),
                display_duration=app.get_display_duration(),
                config=app.config,
                schema=app.schema,
                has_frames=app.frames is not None,
                frame_count=len(app.frames) if app.frames else 0,
                last_render_time=app.last_render_time,
            )

        # Standalone: read from manifest file
        starlark_base = (Path(__file__).resolve().parent.parent.parent / 'starlark-apps').resolve()
        manifest_file = starlark_base / 'manifest.json'
        if not manifest_file.exists():
            return '<div class="text-red-500 p-4">Starlark app not found</div>', 404

        with open(manifest_file, 'r') as f:
            manifest = json.load(f)

        app_data = manifest.get('apps', {}).get(app_id)
        if not app_data:
            return '<div class="text-red-500 p-4">Starlark app not found</div>', 404

        # Load schema from schema.json if it exists — validate path stays within starlark_base
        schema = None
        schema_file = resolve_under(starlark_base, app_id, 'schema.json')
        if schema_file and schema_file.exists():
            try:
                with open(schema_file, 'r') as f:
                    schema = json.load(f)
            except (OSError, json.JSONDecodeError) as e:
                logger.warning("Could not load starlark schema for app: %s", e)

        # Load config from config.json if it exists — validate path stays within starlark_base
        config = {}
        config_file = resolve_under(starlark_base, app_id, 'config.json')
        if config_file and config_file.exists():
            try:
                with open(config_file, 'r') as f:
                    config = json.load(f)
            except (OSError, json.JSONDecodeError) as e:
                logger.warning("Could not load starlark config for app: %s", e)

        return render_template(
            'v3/partials/starlark_config.html',
            app_id=app_id,
            app_name=app_data.get('name', app_id),
            app_enabled=app_data.get('enabled', True),
            render_interval=app_data.get('render_interval', 300),
            display_duration=app_data.get('display_duration', 15),
            config=config,
            schema=schema,
            has_frames=False,
            frame_count=0,
            last_render_time=None,
        )

    except Exception:
        logger.error("[Pages V3] Error loading starlark config for app", exc_info=True)
        return '<div class="text-red-500 p-4">Error loading starlark config; see logs for details</div>', 500