use std::collections::BTreeMap as Map;

pub const TAKE_ALL: i16 = -1;

#[derive(Debug, serde::Deserialize, serde::Serialize)]
pub struct Config {
    pub anti_phishing_code: String,

    #[serde(skip_serializing_if = "Option::is_none")]
    pub keymap: Option<String>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub modules: Option<String>,

    #[serde(skip_serializing_if = "Option::is_none")]
    pub resolv_conf: Option<String>,

    #[serde(default)]
    pub vpns: Map<String, String>,

    pub networks: Vec<Network>,

    pub auths: Vec<Auth>,
    #[serde(default)]
    pub ssh: SSHServer,

    #[serde(default)]
    pub pre_lvm_crypt: Vec<CryptDev>,
    #[serde(default)]
    pub lvm: Vec<LvmVG>,
    #[serde(default)]
    pub crypt: Vec<CryptDev>,

    #[serde(skip_serializing_if = "Option::is_none")]
    pub signer_public_key: Option<String>,

    pub bootstrap: Bootstrap,
}

#[derive(Debug, serde::Deserialize, serde::Serialize)]
pub struct Auth {
    pub name: String,
    #[serde(alias = "sshKey")]
    #[serde(skip_serializing_if = "Option::is_none")]
    pub ssh_key: Option<String>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub password: Option<String>,
}

#[derive(Debug, serde::Deserialize, serde::Serialize)]
pub struct Network {
    pub name: String,
    pub interfaces: Vec<NetworkInterface>,
    pub script: String,
}

#[derive(Debug, serde::Deserialize, serde::Serialize)]
pub struct NetworkInterface {
    pub var: String,
    pub n: i16,
    #[serde(skip_serializing_if = "Vec::is_empty")]
    pub regexps: Vec<String>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub filter: Option<UdevFilter>,
}

#[derive(Clone, Debug, serde::Deserialize, serde::Serialize)]
pub struct SSHServer {
    pub listen: String,
    pub user_ca: Option<String>,
}
impl Default for SSHServer {
    fn default() -> Self {
        Self {
            listen: "[::]:22".to_string(),
            user_ca: None,
        }
    }
}

#[derive(Debug, serde::Deserialize, serde::Serialize)]
pub struct LvmVG {
    #[serde(alias = "vg")]
    pub name: String,
    pub pvs: LvmPV,

    #[serde(default)]
    pub defaults: LvmLVDefaults,

    pub lvs: Vec<LvmLV>,
}

#[derive(Debug, Default, serde::Deserialize, serde::Serialize)]
pub struct LvmLVDefaults {
    #[serde(default)]
    pub fs: Filesystem,
    #[serde(default)]
    pub raid: Raid,
}

#[derive(Debug, serde::Deserialize, serde::Serialize)]
#[serde(rename_all = "snake_case")]
pub enum Filesystem {
    Ext4,
    Xfs,
    Btrfs,
    Other(String),
}

impl Filesystem {
    pub fn fstype(&self) -> &str {
        use Filesystem as F;
        match self {
            F::Ext4 => "ext4",
            F::Xfs => "xfs",
            F::Btrfs => "btrfs",
            F::Other(t) => t,
        }
    }
}

impl Default for Filesystem {
    fn default() -> Self {
        Filesystem::Ext4
    }
}

#[derive(Debug, serde::Deserialize, serde::Serialize)]
pub struct LvmLV {
    pub name: String,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub fs: Option<Filesystem>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub raid: Option<Raid>,
    #[serde(flatten)]
    pub size: LvSize,
}

#[derive(Debug, serde::Deserialize, serde::Serialize)]
#[serde(rename_all = "snake_case")]
pub enum LvSize {
    Size(String),
    Extents(String),
}

#[derive(Debug, serde::Deserialize, serde::Serialize)]
pub struct LvmPV {
    pub n: i16,
    #[serde(skip_serializing_if = "Vec::is_empty")]
    pub regexps: Vec<String>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub udev: Option<UdevFilter>,
}

#[derive(Debug, serde::Deserialize, serde::Serialize)]
pub struct CryptDev {
    pub name: String,
    // hit the limit of enum representation here (flatten + enum variant case)
    #[serde(skip_serializing_if = "Option::is_none")]
    pub dev: Option<String>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub prefix: Option<String>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub udev: Option<UdevFilter>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub optional: Option<bool>,
}
impl CryptDev {
    pub fn filter(&self) -> DevFilter<'_> {
        if let Some(dev) = self.dev.as_deref() {
            DevFilter::Dev(dev)
        } else if let Some(prefix) = self.prefix.as_deref() {
            DevFilter::Prefix(prefix)
        } else if let Some(udev) = self.udev.as_ref() {
            DevFilter::Udev(udev)
        } else {
            DevFilter::None
        }
    }

    pub fn optional(&self) -> bool {
        self.optional.unwrap_or_else(|| match self.filter() {
            DevFilter::None => true,
            DevFilter::Dev(_) => false,
            DevFilter::Prefix(_) => true,
            DevFilter::Udev(_) => true,
        })
    }
}

#[test]
fn test_parse_crypt_dev() {
    for s in [
        "name: sys0\ndev: /dev/sda\n",
        "name: crypt-\nprefix: /dev/sd\n",
        "name: crypt-${name}\nudev: !glob [ DEVNAME, /dev/sd* ]\n",
    ] {
        let dev: CryptDev = serde_yaml::from_str(s).unwrap();
        dev.filter();
        dev.optional();
    }
}

pub enum DevFilter<'t> {
    None,
    Dev(&'t str),
    Prefix(&'t str),
    Udev(&'t UdevFilter),
}

#[derive(Debug, serde::Deserialize, serde::Serialize, Clone)]
#[serde(rename_all = "snake_case")]
pub enum UdevFilter {
    Eq(String, String),
    Glob(String, String),
    And(Vec<UdevFilter>),
    Or(Vec<UdevFilter>),
    Not(Box<UdevFilter>),
}

#[derive(Debug, Default, Clone, serde::Deserialize, serde::Serialize)]
pub struct Raid {
    pub mirrors: Option<u8>,
    pub stripes: Option<u8>,
}

#[derive(Debug, serde::Deserialize, serde::Serialize)]
pub struct Bootstrap {
    pub dev: String,
    pub seed: Option<String>,
}