use std::convert::TryFrom;
use virt::{domain::{Domain, DomainState}};
use serde::{Serialize, Deserialize};

use crate::errors::Error;

/**
 * Defines the amount of memory a planet has
 */
#[derive(Debug, Serialize, Deserialize)]
pub struct Memory(pub u64);

impl From<u64> for Memory {
    fn from(u: u64) -> Self {
        Self(u)
    }
}

/**
 * Defines the number of vCPUs a planet has
 */
#[derive(Debug, Serialize, Deserialize)]
pub struct CpuCount(pub u64);

impl From<u64> for CpuCount {
    fn from(u: u64) -> Self {
        Self(u)
    }
}

/**
 * Represents a virtual machine, that's active on some server
 *
 * In keeping with the theme, it's named [Planet] :)
 *
 * There is a private `domain` field that contains a reference to the actual domain. This will not
 * be (de)serialized, and, if needed across a network, should be recreated from the `host` and
 * `uuid` attributes using [virt::domain::lookup_from_uuid_string]
 */
#[derive(Debug, Serialize, Deserialize)]
pub struct Planet {
    /// The reference name of the machine
    pub name: String,

    /// The physical machine where this one lives
    pub host: String,

    /// The UUID
    pub uuid: String,

    /// The network address where this machine can be reached
    pub addr: Option<String>,

    /// The amount of RAM (in MB) assigned to this machine
    pub mem: Memory,

    /// The amount of vCPUs assigned to this machine
    pub cpu_count: CpuCount,

    #[serde(skip)]
    domain: Option<Domain>,
}

impl PartialEq for Planet {
    fn eq(&self, other: &Self) -> bool {
        self.uuid == other.uuid
    }
}

impl TryFrom<Domain> for Planet {
    type Error = Error;

    fn try_from(d: Domain) -> Result<Self, Self::Error> {
        let c = d.get_connect()?;

        // This... feels wrong
        //
        // I know it probably works
        //
        // Based on code by Cadey in waifud
        let addr: Option<String> = if d.is_active()? {
            let mut addr: Vec<String> = d
                .interface_addresses(virt::domain::VIR_DOMAIN_INTERFACE_ADDRESSES_SRC_LEASE, 0)?
                .into_iter()
                .map(|iface| iface.addrs.clone())
                .filter(|addrs| addrs.get(0).is_some())
                .map(|addrs| addrs.get(0).unwrap().clone().addr)
                .collect();

            if addr.get(0).is_none() {
                Some(String::from("localhost"))
            } else {
                Some(addr.swap_remove(0))
            }
        } else {
            None
        };

        Ok(Self {
            name: d.get_name()?,
            host: c.get_hostname()?,
            addr,
            uuid: d.get_uuid_string()?,
            mem: d.get_max_memory()?.into(),
            cpu_count: d.get_max_vcpus()?.into(),
            domain: Some(d),
        })
    }
}


impl TryFrom<&Domain> for Planet {
    type Error = Error;

    fn try_from(d: &Domain) -> Result<Self, Self::Error> {
        let c = d.get_connect()?;

        // This... feels wrong
        //
        // I know it probably works
        //
        // Based on code by Cadey in waifud
        let addr: Option<String> = if d.is_active()? {
            let mut addr: Vec<String> = d
                .interface_addresses(virt::domain::VIR_DOMAIN_INTERFACE_ADDRESSES_SRC_LEASE, 0)?
                .into_iter()
                .map(|iface| iface.addrs.clone())
                .filter(|addrs| addrs.get(0).is_some())
                .map(|addrs| addrs.get(0).unwrap().clone().addr)
                .collect();

            if addr.get(0).is_none() {
                Some(String::from("localhost"))
            } else {
                Some(addr.swap_remove(0))
            }
        } else {
            None
        };

        Ok(Self {
            name: d.get_name()?,
            host: c.get_hostname()?,
            addr,
            uuid: d.get_uuid_string()?,
            mem: d.get_max_memory()?.into(),
            cpu_count: d.get_max_vcpus()?.into(),
            domain: Some(*d),
        })
    }
}

#[repr(u32)]
#[derive(Serialize, Deserialize)]
pub enum Health {
    Unknown = 0,
    Running = 1,
    Blocked = 2,
    Paused  = 3,
    ShuttingDown = 4,
    ShutDown = 5,
    Crashed = 6,
    GuestSuspended = 7
}

impl Planet {
    fn get_status(&self) -> Result<Health, Error> {
        let d = match self.domain {
            Some(d) => d,
            None => {
                return Err(Error::Other(String::from("No domain connection found")));
            }
        };

        let state = d.get_state()?;

        Ok(state.0 as Health)
    }
}