use super::BrocadeClient;
use crate::{
    BrocadeInfo, Error, ExecutionMode, InterSwitchLink, InterfaceInfo, MacAddressEntry,
    PortChannelId, PortOperatingMode, parse_brocade_mac_address, shell::BrocadeShell,
};

use async_trait::async_trait;
use harmony_types::switch::{PortDeclaration, PortLocation};
use log::{debug, info};
use regex::Regex;
use std::{collections::HashSet, str::FromStr};

#[derive(Debug)]
pub struct FastIronClient {
    shell: BrocadeShell,
    version: BrocadeInfo,
}

impl FastIronClient {
    pub fn init(mut shell: BrocadeShell, version_info: BrocadeInfo) -> Self {
        shell.before_all(vec!["skip-page-display".into()]);
        shell.after_all(vec!["page".into()]);

        Self {
            shell,
            version: version_info,
        }
    }

    fn parse_mac_entry(&self, line: &str) -> Option<Result<MacAddressEntry, Error>> {
        debug!("[Brocade] Parsing mac address entry: {line}");
        let parts: Vec<&str> = line.split_whitespace().collect();
        if parts.len() < 3 {
            return None;
        }

        let (vlan, mac_address, port) = match parts.len() {
            3 => (
                u16::from_str(parts[0]).ok()?,
                parse_brocade_mac_address(parts[1]).ok()?,
                parts[2].to_string(),
            ),
            _ => (
                1,
                parse_brocade_mac_address(parts[0]).ok()?,
                parts[1].to_string(),
            ),
        };

        let port =
            PortDeclaration::parse(&port).map_err(|e| Error::UnexpectedError(format!("{e}")));

        match port {
            Ok(p) => Some(Ok(MacAddressEntry {
                vlan,
                mac_address,
                port: p,
            })),
            Err(e) => Some(Err(e)),
        }
    }

    fn parse_stack_port_entry(&self, line: &str) -> Option<Result<InterSwitchLink, Error>> {
        debug!("[Brocade] Parsing stack port entry: {line}");
        let parts: Vec<&str> = line.split_whitespace().collect();
        if parts.len() < 10 {
            return None;
        }

        let local_port = PortLocation::from_str(parts[0]).ok()?;

        Some(Ok(InterSwitchLink {
            local_port,
            remote_port: None,
        }))
    }

    fn build_port_channel_commands(
        &self,
        channel_id: PortChannelId,
        channel_name: &str,
        ports: &[PortLocation],
    ) -> Vec<String> {
        let mut commands = vec![
            "configure terminal".to_string(),
            format!("lag {channel_name} static id {channel_id}"),
        ];

        for port in ports {
            commands.push(format!("ports ethernet {port}"));
        }

        commands.push(format!("primary-port {}", ports[0]));
        commands.push("deploy".into());
        commands.push("exit".into());
        commands.push("write memory".into());
        commands.push("exit".into());

        commands
    }
}

#[async_trait]
impl BrocadeClient for FastIronClient {
    async fn version(&self) -> Result<BrocadeInfo, Error> {
        Ok(self.version.clone())
    }

    async fn get_mac_address_table(&self) -> Result<Vec<MacAddressEntry>, Error> {
        info!("[Brocade] Showing MAC address table...");

        let output = self
            .shell
            .run_command("show mac-address", ExecutionMode::Regular)
            .await?;

        output
            .lines()
            .skip(2)
            .filter_map(|line| self.parse_mac_entry(line))
            .collect()
    }

    async fn get_stack_topology(&self) -> Result<Vec<InterSwitchLink>, Error> {
        let output = self
            .shell
            .run_command("show interface stack-ports", crate::ExecutionMode::Regular)
            .await?;

        output
            .lines()
            .skip(1)
            .filter_map(|line| self.parse_stack_port_entry(line))
            .collect()
    }

    async fn get_interfaces(&self) -> Result<Vec<InterfaceInfo>, Error> {
        todo!()
    }

    async fn configure_interfaces(
        &self,
        _interfaces: Vec<(String, PortOperatingMode)>,
    ) -> Result<(), Error> {
        todo!()
    }

    async fn find_available_channel_id(&self) -> Result<PortChannelId, Error> {
        info!("[Brocade] Finding next available channel id...");

        let output = self
            .shell
            .run_command("show lag", ExecutionMode::Regular)
            .await?;
        let re = Regex::new(r"=== LAG .* ID\s+(\d+)").expect("Invalid regex");

        let used_ids: HashSet<u8> = output
            .lines()
            .filter_map(|line| {
                re.captures(line)
                    .and_then(|c| c.get(1))
                    .and_then(|id_match| id_match.as_str().parse().ok())
            })
            .collect();

        let mut next_id: u8 = 1;
        loop {
            if !used_ids.contains(&next_id) {
                break;
            }
            next_id += 1;
        }

        info!("[Brocade] Found channel id: {next_id}");
        Ok(next_id)
    }

    async fn create_port_channel(
        &self,
        channel_id: PortChannelId,
        channel_name: &str,
        ports: &[PortLocation],
    ) -> Result<(), Error> {
        info!(
            "[Brocade] Configuring port-channel '{channel_name} {channel_id}' with ports: {ports:?}"
        );

        let commands = self.build_port_channel_commands(channel_id, channel_name, ports);
        self.shell
            .run_commands(commands, ExecutionMode::Privileged)
            .await?;

        info!("[Brocade] Port-channel '{channel_name}' configured.");
        Ok(())
    }

    async fn clear_port_channel(&self, channel_name: &str) -> Result<(), Error> {
        info!("[Brocade] Clearing port-channel: {channel_name}");

        let commands = vec![
            "configure terminal".to_string(),
            format!("no lag {channel_name}"),
            "write memory".to_string(),
        ];
        self.shell
            .run_commands(commands, ExecutionMode::Privileged)
            .await?;

        info!("[Brocade] Port-channel '{channel_name}' cleared.");
        Ok(())
    }
}