use crate::domain::{self, acme, checker, config};
use crate::error::{MapUnexpected, ToUnexpected};
use crate::{error, origin};

use std::{future, pin, sync};

#[derive(thiserror::Error, Debug)]
pub enum GetConfigError {
    #[error("not found")]
    NotFound,

    #[error(transparent)]
    Unexpected(#[from] error::Unexpected),
}

impl From<config::GetError> for GetConfigError {
    fn from(e: config::GetError) -> GetConfigError {
        match e {
            config::GetError::NotFound => GetConfigError::NotFound,
            config::GetError::Unexpected(e) => GetConfigError::Unexpected(e),
        }
    }
}

#[derive(thiserror::Error, Debug)]
pub enum GetOriginError {
    #[error("not found")]
    NotFound,

    #[error(transparent)]
    Unexpected(#[from] error::Unexpected),
}

impl From<config::GetError> for GetOriginError {
    fn from(e: config::GetError) -> GetOriginError {
        match e {
            config::GetError::NotFound => GetOriginError::NotFound,
            config::GetError::Unexpected(e) => GetOriginError::Unexpected(e),
        }
    }
}

#[derive(thiserror::Error, Debug)]
pub enum SyncError {
    #[error("not found")]
    NotFound,

    #[error("already in progress")]
    AlreadyInProgress,

    #[error(transparent)]
    Unexpected(#[from] error::Unexpected),
}

impl From<config::GetError> for SyncError {
    fn from(e: config::GetError) -> SyncError {
        match e {
            config::GetError::NotFound => SyncError::NotFound,
            config::GetError::Unexpected(e) => SyncError::Unexpected(e),
        }
    }
}

#[derive(thiserror::Error, Debug)]
pub enum SyncWithConfigError {
    #[error("invalid url")]
    InvalidURL,

    #[error("invalid branch name")]
    InvalidBranchName,

    #[error("already in progress")]
    AlreadyInProgress,

    #[error("target A/AAAA not set")]
    TargetANotSet,

    #[error("challenge token not set")]
    ChallengeTokenNotSet,

    #[error(transparent)]
    Unexpected(#[from] error::Unexpected),
}

impl From<origin::store::SyncError> for SyncWithConfigError {
    fn from(e: origin::store::SyncError) -> SyncWithConfigError {
        match e {
            origin::store::SyncError::InvalidURL => SyncWithConfigError::InvalidURL,
            origin::store::SyncError::InvalidBranchName => SyncWithConfigError::InvalidBranchName,
            origin::store::SyncError::AlreadyInProgress => SyncWithConfigError::AlreadyInProgress,
            origin::store::SyncError::Unexpected(e) => SyncWithConfigError::Unexpected(e),
        }
    }
}

impl From<checker::CheckDomainError> for SyncWithConfigError {
    fn from(e: checker::CheckDomainError) -> SyncWithConfigError {
        match e {
            checker::CheckDomainError::TargetANotSet => SyncWithConfigError::TargetANotSet,
            checker::CheckDomainError::ChallengeTokenNotSet => {
                SyncWithConfigError::ChallengeTokenNotSet
            }
            checker::CheckDomainError::Unexpected(e) => SyncWithConfigError::Unexpected(e),
        }
    }
}

impl From<config::SetError> for SyncWithConfigError {
    fn from(e: config::SetError) -> SyncWithConfigError {
        match e {
            config::SetError::Unexpected(e) => SyncWithConfigError::Unexpected(e),
        }
    }
}

pub type GetAcmeHttp01ChallengeKeyError = acme::manager::GetHttp01ChallengeKeyError;

pub type AllDomainsResult<T> = config::AllDomainsResult<T>;

#[mockall::automock(
    type Origin=origin::MockOrigin;
    type SyncWithConfigFuture=future::Ready<Result<(), SyncWithConfigError>>;
    type SyncAllOriginsErrorsIter=Vec<(Option<origin::Descr>,error::Unexpected)>;
)]
pub trait Manager {
    type Origin<'mgr>: origin::Origin + 'mgr
    where
        Self: 'mgr;

    type SyncWithConfigFuture<'mgr>: future::Future<Output = Result<(), SyncWithConfigError>>
        + Send
        + Unpin
        + 'mgr
    where
        Self: 'mgr;

    type SyncAllOriginsErrorsIter<'mgr>: IntoIterator<Item = (Option<origin::Descr>, error::Unexpected)>
        + 'mgr
    where
        Self: 'mgr;

    fn get_config(&self, domain: &domain::Name) -> Result<config::Config, GetConfigError>;

    fn get_origin(&self, domain: &domain::Name) -> Result<Self::Origin<'_>, GetOriginError>;

    fn sync_with_config(
        &self,
        domain: domain::Name,
        config: config::Config,
    ) -> Self::SyncWithConfigFuture<'_>;

    fn sync_all_origins(&self) -> Result<Self::SyncAllOriginsErrorsIter<'_>, error::Unexpected>;

    fn get_acme_http01_challenge_key(
        &self,
        token: &str,
    ) -> Result<String, GetAcmeHttp01ChallengeKeyError>;

    fn all_domains(&self) -> AllDomainsResult<Vec<AllDomainsResult<domain::Name>>>;
}

pub trait BoxedManager: Manager + Send + Sync + Clone {}

struct ManagerImpl<OriginStore, DomainConfigStore, AcmeManager>
where
    OriginStore: origin::store::BoxedStore,
    DomainConfigStore: config::BoxedStore,
    AcmeManager: acme::manager::BoxedManager,
{
    origin_store: OriginStore,
    domain_config_store: DomainConfigStore,
    domain_checker: checker::DNSChecker,
    acme_manager: Option<AcmeManager>,
}

pub fn new<OriginStore, DomainConfigStore, AcmeManager>(
    origin_store: OriginStore,
    domain_config_store: DomainConfigStore,
    domain_checker: checker::DNSChecker,
    acme_manager: Option<AcmeManager>,
) -> impl BoxedManager
where
    OriginStore: origin::store::BoxedStore,
    DomainConfigStore: config::BoxedStore,
    AcmeManager: acme::manager::BoxedManager,
{
    sync::Arc::new(ManagerImpl {
        origin_store,
        domain_config_store,
        domain_checker,
        acme_manager,
    })
}

impl<OriginStore, DomainConfigStore, AcmeManager> BoxedManager
    for sync::Arc<ManagerImpl<OriginStore, DomainConfigStore, AcmeManager>>
where
    OriginStore: origin::store::BoxedStore,
    DomainConfigStore: config::BoxedStore,
    AcmeManager: acme::manager::BoxedManager,
{
}

impl<OriginStore, DomainConfigStore, AcmeManager> Manager
    for sync::Arc<ManagerImpl<OriginStore, DomainConfigStore, AcmeManager>>
where
    OriginStore: origin::store::BoxedStore,
    DomainConfigStore: config::BoxedStore,
    AcmeManager: acme::manager::BoxedManager,
{
    type Origin<'mgr> = OriginStore::Origin<'mgr>
        where Self: 'mgr;

    type SyncWithConfigFuture<'mgr> = pin::Pin<Box<dyn future::Future<Output = Result<(), SyncWithConfigError>> + Send + 'mgr>>
        where Self: 'mgr;

    type SyncAllOriginsErrorsIter<'mgr> = Box<dyn Iterator<Item = (Option<origin::Descr>, error::Unexpected)> + 'mgr>
        where Self: 'mgr;

    fn get_config(&self, domain: &domain::Name) -> Result<config::Config, GetConfigError> {
        Ok(self.domain_config_store.get(domain)?)
    }

    fn get_origin(&self, domain: &domain::Name) -> Result<Self::Origin<'_>, GetOriginError> {
        let config = self.domain_config_store.get(domain)?;
        let origin = self
            .origin_store
            .get(config.origin_descr)
            // if there's a config there should be an origin, any error here is unexpected
            .map_unexpected()?;
        Ok(origin)
    }

    fn sync_with_config(
        &self,
        domain: domain::Name,
        config: config::Config,
    ) -> Self::SyncWithConfigFuture<'_> {
        Box::pin(async move {
            let config_hash = config.hash().map_unexpected()?;

            self.domain_checker
                .check_domain(&domain, &config_hash)
                .await?;

            self.origin_store
                .sync(config.origin_descr.clone(), origin::store::Limits {})?;

            self.domain_config_store.set(&domain, &config)?;

            if let Some(ref acme_manager) = self.acme_manager {
                acme_manager.sync_domain(domain.clone()).await?;
            }

            Ok(())
        })
    }

    fn sync_all_origins(&self) -> Result<Self::SyncAllOriginsErrorsIter<'_>, error::Unexpected> {
        let iter = self.origin_store.all_descrs().map_unexpected()?.into_iter();

        Ok(Box::from(iter.filter_map(|descr| {
            if let Err(err) = descr {
                return Some((None, err.to_unexpected()));
            }

            let descr = descr.unwrap();

            if let Err(err) = self
                .origin_store
                .sync(descr.clone(), origin::store::Limits {})
            {
                return Some((Some(descr), err.to_unexpected()));
            }

            None
        })))
    }

    fn get_acme_http01_challenge_key(
        &self,
        token: &str,
    ) -> Result<String, GetAcmeHttp01ChallengeKeyError> {
        if let Some(ref acme_manager) = self.acme_manager {
            return acme_manager.get_http01_challenge_key(token);
        }

        Err(GetAcmeHttp01ChallengeKeyError::NotFound)
    }

    fn all_domains(&self) -> AllDomainsResult<Vec<AllDomainsResult<domain::Name>>> {
        self.domain_config_store.all_domains()
    }
}