use anyhow::{Context, Result};
use tracing::info;

use crate::tollgate::TollGateConfig;
use crate::Router;

/// Create a dedicated pay-as-you-go WiFi interface for TollGate.
///
/// Adds a new `wifi-iface` section on the first detected radio, sets the SSID,
/// marks it as an open network, and ties it to a TollGate firewall zone.
pub fn provision_ssid(router: &Router, cfg: &TollGateConfig) -> Result<()> {
    let radio = detect_radio(router).context("detect WiFi radio")?;
    info!("[{}] Using radio {} for TollGate SSID", router.host, radio);

    // Add a new wifi-iface section; uci add returns the section name (e.g. "cfg123456").
    let section = router.uci_add("wireless", "wifi-iface")?;

    router.uci_apply(
        "wireless",
        &[
            (&format!("wireless.{}.device", section), &radio),
            (&format!("wireless.{}.mode", section), "ap"),
            (&format!("wireless.{}.ssid", section), &cfg.ssid),
            (&format!("wireless.{}.encryption", section), "none"),
            (&format!("wireless.{}.network", section), "tollgate"),
            // Disable 802.11r/k/v — unnecessary for transient pay-as-you-go clients.
            (&format!("wireless.{}.ieee80211r", section), "0"),
        ],
    )?;

    provision_network(router)?;
    provision_firewall(router)?;

    Ok(())
}

/// Add a `tollgate` network interface (isolated LAN for TollGate clients).
fn provision_network(router: &Router) -> Result<()> {
    router.uci_apply(
        "network",
        &[
            ("network.tollgate", "interface"),
            ("network.tollgate.proto", "static"),
            ("network.tollgate.ipaddr", "192.168.99.1"),
            ("network.tollgate.netmask", "255.255.255.0"),
        ],
    )?;

    // Enable DHCP for the tollgate interface.
    router.uci_apply(
        "dhcp",
        &[
            ("dhcp.tollgate", "dhcp"),
            ("dhcp.tollgate.interface", "tollgate"),
            ("dhcp.tollgate.start", "100"),
            ("dhcp.tollgate.limit", "150"),
            ("dhcp.tollgate.leasetime", "5m"),
        ],
    )?;

    Ok(())
}

/// Add firewall zone for the tollgate interface.
///
/// TollGate itself gates forwarding via iptables; the firewall zone isolates
/// tollgate clients from other LAN segments.
fn provision_firewall(router: &Router) -> Result<()> {
    // Zone
    router.uci_apply(
        "firewall",
        &[
            ("firewall.tollgate_zone", "zone"),
            ("firewall.tollgate_zone.name", "tollgate"),
            ("firewall.tollgate_zone.network", "tollgate"),
            ("firewall.tollgate_zone.input", "ACCEPT"),
            ("firewall.tollgate_zone.output", "ACCEPT"),
            ("firewall.tollgate_zone.forward", "REJECT"),
        ],
    )?;

    // Forwarding rule: tollgate → wan (TollGate manages which clients can forward)
    router.uci_apply(
        "firewall",
        &[
            ("firewall.tollgate_fwd", "forwarding"),
            ("firewall.tollgate_fwd.src", "tollgate"),
            ("firewall.tollgate_fwd.dest", "wan"),
        ],
    )?;

    Ok(())
}

/// Return the first available wireless radio device name (e.g. "radio0").
fn detect_radio(router: &Router) -> Result<String> {
    let out = router.run_ok("uci show wireless | grep -o 'wireless\\.radio[0-9]*\\.type' | head -1")?;
    // Extract "radioN" from "wireless.radioN.type"
    let radio = out
        .trim()
        .split('.')
        .nth(1)
        .unwrap_or("radio0")
        .to_string();
    Ok(radio)
}