use crate::NetworkDomainPermissions;
use crate::NetworkProxyConfig;
use crate::NetworkUnixSocketPermission;
use crate::NetworkUnixSocketPermissions;
use serde::Deserialize;
use serde::Serialize;

/// Managed proxy requirements supplied by the owner of one execution environment.
///
/// The owner can require proxy routing without granting direct network access.
/// Listeners, network mode, MITM, and credentials remain controller-owned.
#[derive(Clone, Debug, Deserialize, Eq, PartialEq, Serialize)]
#[serde(rename_all = "camelCase")]
pub struct EnvironmentNetworkPolicy {
    /// Requires managed proxy routing even when direct network access is restricted.
    /// False or omission leaves activation to the controller and command permissions.
    #[serde(default, skip_serializing_if = "std::ops::Not::not")]
    pub requires_proxy: bool,
    pub domains: Option<NetworkDomainPermissions>,
    /// Managed host selectors inherited by every execution in this environment.
    #[serde(default, skip_serializing_if = "Vec::is_empty")]
    pub review_domains: Vec<String>,
    pub unix_sockets: Option<NetworkUnixSocketPermissions>,
    pub allow_upstream_proxy: bool,
    pub dangerously_allow_all_unix_sockets: bool,
    /// Omission inherits local-binding policy; an explicit false remains a restriction.
    pub allow_local_binding: Option<bool>,
    pub managed_allowed_domains_only: bool,
}

impl EnvironmentNetworkPolicy {
    /// Captures proxy activation and traffic restrictions without controller runtime settings.
    pub fn from_config(config: &NetworkProxyConfig, managed_allowed_domains_only: bool) -> Self {
        Self {
            requires_proxy: config.enabled,
            domains: config.domains.clone(),
            review_domains: config.review_domains.clone(),
            unix_sockets: config.unix_sockets.clone(),
            allow_upstream_proxy: config.allow_upstream_proxy,
            dangerously_allow_all_unix_sockets: config
                .dangerously_allow_all_unix_sockets
                .unwrap_or(false),
            allow_local_binding: config.allow_local_binding,
            managed_allowed_domains_only,
        }
    }

    /// Applies attachment-owned traffic settings while preserving inherited denials and proxy setup.
    pub fn apply_to(&self, config: &mut NetworkProxyConfig) {
        // Neither owner nor controller may remove the other's review selectors.
        for pattern in &self.review_domains {
            if !config
                .review_domains
                .iter()
                .any(|existing| existing.eq_ignore_ascii_case(pattern))
            {
                config.review_domains.push(pattern.clone());
            }
        }
        // Use the owner's domain rules without dropping controller denials.
        let inherited_denials = config.denied_domains().unwrap_or_default();
        config.domains.clone_from(&self.domains);
        for domain in inherited_denials {
            config.upsert_domain_permission(
                domain,
                crate::NetworkDomainPermission::Deny,
                crate::normalize_host,
            );
        }
        // An omitted controller policy leaves socket permissions to the attachment;
        // an explicitly empty socket map still supplies a restrictive ceiling.
        let inherited_allow_all = config
            .dangerously_allow_all_unix_sockets
            .unwrap_or(config.unix_sockets.is_none());
        let inherited_sockets = config.unix_sockets.take().unwrap_or_default();
        let mut effective_sockets = self.unix_sockets.clone().unwrap_or_default();

        // "Allow all" cannot override a socket denied by either policy.
        let inherited_permits_all = inherited_allow_all
            && !inherited_sockets
                .entries
                .values()
                .any(|permission| matches!(permission, NetworkUnixSocketPermission::Deny));
        let owner_permits_all = self.dangerously_allow_all_unix_sockets
            && !effective_sockets
                .entries
                .values()
                .any(|permission| matches!(permission, NetworkUnixSocketPermission::Deny));

        // Keep shared socket grants; controller denials always take priority.
        effective_sockets.entries.retain(|path, permission| {
            matches!(permission, NetworkUnixSocketPermission::Deny)
                || inherited_permits_all
                || matches!(
                    inherited_sockets.entries.get(path),
                    Some(NetworkUnixSocketPermission::Allow)
                )
        });
        for (path, permission) in inherited_sockets.entries {
            if owner_permits_all || matches!(permission, NetworkUnixSocketPermission::Deny) {
                effective_sockets.entries.insert(path, permission);
            }
        }

        // Socket and upstream-proxy permissions require both controller and owner grants.
        config.unix_sockets = (!effective_sockets.entries.is_empty()).then_some(effective_sockets);
        config.dangerously_allow_all_unix_sockets =
            Some(inherited_permits_all && owner_permits_all);
        config.allow_upstream_proxy &= self.allow_upstream_proxy;
        // Either explicit denial wins; defer unresolved defaults to the executor.
        config.allow_local_binding = match (config.allow_local_binding, self.allow_local_binding) {
            (Some(controller), Some(owner)) => Some(controller && owner),
            (controller, owner) => controller.or(owner),
        };
    }
}