#![allow(missing_docs)]

use std::vec::Vec;
use std::io::{Read, Write};
use std::fs::File;
use std::path::{Path, PathBuf};

#[cfg(feature = "upgrade")]
use semver::Version;

use serde_json;
use sha1;
use hyper::{self, Client};
use hyper::net::HttpsConnector;
use hyper::header::{Authorization, Basic};
use hyper::status::StatusCode;
use hyper_native_tls::NativeTlsClient;

use core::{CliError, LalResult};


/// Artifactory credentials
#[derive(Serialize, Deserialize, Clone)]
pub struct Credentials {
    /// Upload username
    pub username: String,
    /// Upload password
    pub password: String,
}

/// Static Artifactory locations
#[derive(Serialize, Deserialize, Clone, Default)]
pub struct ArtifactoryConfig {
    /// Location of artifactory API master (for API queries)
    pub master: String,
    /// Location of artifactory slave (for fetching artifacts)
    pub slave: String,
    /// Release group name (for API queries)
    pub release: String,
    /// Virtual group (for downloads)
    pub vgroup: String,
    /// Optional publish credentials
    pub credentials: Option<Credentials>,
}


// Need these to query for stored artifacts:
// This query has tons of info, but we only care about the version
// And the version is encoded in children.uri with leading slash
#[derive(Deserialize)]
struct ArtifactoryVersion {
    uri: String, // folder: bool,
}
#[derive(Deserialize)]
struct ArtifactoryStorageResponse {
    children: Vec<ArtifactoryVersion>,
}

// simple request body fetcher
fn hyper_req(url: &str) -> LalResult<String> {
    let client = Client::with_connector(HttpsConnector::new(NativeTlsClient::new().unwrap()));
    let mut res = client.get(url).send()?;
    if res.status != hyper::Ok {
        return Err(CliError::BackendFailure(format!("GET request with {}", res.status)));
    }
    let mut body = String::new();
    res.read_to_string(&mut body)?;
    Ok(body)
}

// simple request downloader
pub fn http_download_to_path(url: &str, save: &PathBuf) -> LalResult<()> {
    debug!("GET {}", url);
    let client = Client::with_connector(HttpsConnector::new(NativeTlsClient::new().unwrap()));
    let mut res = client.get(url).send()?;
    if res.status != hyper::Ok {
        return Err(CliError::BackendFailure(format!("GET request with {}", res.status)));
    }

    if cfg!(feature = "progress") {
        #[cfg(feature = "progress")]
        {
            use indicatif::{ProgressBar, ProgressStyle};
            let total_size = res.headers.get::<hyper::header::ContentLength>().unwrap().0;
            let mut downloaded = 0;
            let mut buffer = [0; 1024 * 64];
            let mut f = File::create(save)?;
            let pb = ProgressBar::new(total_size);
            pb.set_style(ProgressStyle::default_bar()
                             .template("{bar:40.yellow/black} {bytes}/{total_bytes} ({eta})"));

            while downloaded < total_size {
                let read = res.read(&mut buffer)?;
                f.write_all(&buffer[0..read])?;
                downloaded += read as u64;
                pb.set_position(downloaded);
            }
            f.flush()?;
        }
    } else {
        let mut buffer: Vec<u8> = Vec::new();
        res.read_to_end(&mut buffer)?;
        let mut f = File::create(save)?;
        f.write_all(&buffer)?;
    }
    Ok(())
}


/// Query the Artifactory storage api
///
/// This will get, then parse all results as u32s, and return this list.
/// This assumes versoning is done via a single integer.
fn get_storage_versions(uri: &str) -> LalResult<Vec<u32>> {
    debug!("GET {}", uri);

    let resp = hyper_req(uri)
        .map_err(|e| {
            warn!("Failed to GET {}: {}", uri, e);
            CliError::BackendFailure("No version information found on API".into())
        })?;

    trace!("Got body {}", resp);

    let res: ArtifactoryStorageResponse = serde_json::from_str(&resp)?;
    let builds: Vec<u32> = res.children
        .iter()
        .map(|r| r.uri.as_str())
        .map(|r| r.trim_matches('/'))
        .filter_map(|b| b.parse().ok())
        .collect();
    Ok(builds)
}

// artifactory extra headers
header! {(XCheckSumDeploy, "X-Checksum-Deploy") => [String]}
header! {(XCheckSumSha1, "X-Checksum-Sha1") => [String]}

/// Upload a tarball to artifactory
///
/// This is using a http basic auth PUT to artifactory using config credentials.
fn upload_artifact(arti: &ArtifactoryConfig, uri: &str, f: &mut File) -> LalResult<()> {
    if let Some(creds) = arti.credentials.clone() {
        let client = Client::new();

        let mut buffer: Vec<u8> = Vec::new();
        f.read_to_end(&mut buffer)?;

        let full_uri = format!("{}/{}/{}", arti.slave, arti.release, uri);

        let mut sha = sha1::Sha1::new();
        sha.update(&buffer);

        let auth = Authorization(Basic {
                                     username: creds.username,
                                     password: Some(creds.password),
                                 });

        // upload the artifact
        info!("PUT {}", full_uri);
        let resp = client.put(&full_uri[..]).header(auth.clone()).body(&buffer[..]).send()?;
        debug!("resp={:?}", resp);
        let respstr = format!("{} from PUT {}", resp.status, full_uri);
        if resp.status != StatusCode::Created {
            return Err(CliError::UploadFailure(respstr));
        }
        debug!("{}", respstr);

        // do another request to get the hash on artifactory
        // jfrog api does not allow do do both at once - and this also creates the md5 (somehow)
        // this creates ${full_uri}.sha1 and ${full_uri}.md5 (although we just gave it the sha..)
        // This `respsha` can fail if engci-maven becomes inconsistent. NotFound has been seen.
        // And that makes no sense because the above must have returned Created to get here..
        info!("PUT {} (X-Checksum-Sha1)", full_uri);
        let respsha = client
            .put(&full_uri[..])
            .header(XCheckSumDeploy("true".into()))
            .header(XCheckSumSha1(sha.digest().to_string()))
            .header(auth)
            .send()?;
        debug!("respsha={:?}", respsha);
        let respshastr = format!("{} from PUT {} (X-Checksum-Sha1)", respsha.status, full_uri);
        if respsha.status != StatusCode::Created {
            return Err(CliError::UploadFailure(respshastr));
        }
        debug!("{}", respshastr);

        Ok(())
    } else {
        Err(CliError::MissingBackendCredentials)
    }
}

/// Get the maximal version number from the storage api
fn get_storage_as_u32(uri: &str) -> LalResult<u32> {
    if let Some(&latest) = get_storage_versions(uri)?.iter().max() {
        Ok(latest)
    } else {
        Err(CliError::BackendFailure("No version information found on API".into()))
    }
}

// The URL for a component tarball stored in the default artifactory location
fn get_dependency_url_default(art_cfg: &ArtifactoryConfig, name: &str, version: u32) -> String {
    let tar_url = format!("{}/{}/{}/{}/{}.tar.gz",
                          art_cfg.slave,
                          art_cfg.vgroup,
                          name,
                          version.to_string(),
                          name);

    trace!("Inferring tarball location as {}", tar_url);
    tar_url
}

// The URL for a component tarball under the one of the environment trees
fn get_dependency_env_url(
    art_cfg: &ArtifactoryConfig,
    name: &str,
    version: u32,
    env: &str,
) -> String {
    let tar_url = format!("{}/{}/env/{}/{}/{}/{}.tar.gz",
                          art_cfg.slave,
                          art_cfg.vgroup,
                          env,
                          name,
                          version.to_string(),
                          name);

    trace!("Inferring tarball location as {}", tar_url);
    tar_url
}

fn get_dependency_url(
    art_cfg: &ArtifactoryConfig,
    name: &str,
    version: u32,
    env: Option<&str>,
) -> String {
    if let Some(e) = env {
        get_dependency_env_url(art_cfg, name, version, e)
    } else {
        // This is only used by lal export without -e
        get_dependency_url_default(art_cfg, name, version)
    }
}

fn get_dependency_url_latest(
    art_cfg: &ArtifactoryConfig,
    name: &str,
    env: Option<&str>,
) -> LalResult<Component> {
    let url = format!("{}/api/storage/{}/{}",
                      art_cfg.master,
                      art_cfg.release,
                      name);
    let v = get_storage_as_u32(&url)?;

    debug!("Found latest version as {}", v);
    Ok(Component {
           tarball: get_dependency_url(art_cfg, name, v, env),
           version: v,
           name: name.into(),
       })
}

// This queries the API for the default location
// if a default exists, then all our current multi-builds must exist
fn get_latest_versions(
    art_cfg: &ArtifactoryConfig,
    name: &str,
    env: Option<&str>,
) -> LalResult<Vec<u32>> {
    let url = match env {
        Some(e) => {
            format!("{}/api/storage/{}/{}/{}/{}",
                    art_cfg.master,
                    art_cfg.release,
                    "env",
                    e,
                    name)
        }
        None => {
            format!("{}/api/storage/{}/{}",
                    art_cfg.master,
                    art_cfg.release,
                    name)
        }
    };
    get_storage_versions(&url)
}

/// Main entry point for install
fn get_tarball_uri(
    art_cfg: &ArtifactoryConfig,
    name: &str,
    version: Option<u32>,
    env: Option<&str>,
) -> LalResult<Component> {
    if let Some(v) = version {
        Ok(Component {
               tarball: get_dependency_url(art_cfg, name, v, env),
               version: v,
               name: name.into(),
           })
    } else {
        get_dependency_url_latest(art_cfg, name, env)
    }
}

/// Latest lal version - as seen on artifactory
#[cfg(feature = "upgrade")]
pub struct LatestLal {
    /// URL of the latest tarball
    pub url: String,
    /// Semver::Version of the latest tarball
    pub version: Version,
}

/// Entry point for `lal::upgrade`
///
/// This mostly duplicates the behaviour in `get_storage_as_u32`, however,
/// it is parsing the version as a `semver::Version` struct rather than a u32.
/// This is used regardless of your used backend because we want people to use our
/// main release of lal on CME-release on cisco artifactory at the moment.
#[cfg(feature = "upgrade")]
pub fn get_latest_lal_version() -> LalResult<LatestLal> {
    // canonical latest url
    let uri = "https://engci-maven-master.cisco.com/artifactory/api/storage/CME-release/lal";
    debug!("GET {}", uri);
    let resp = hyper_req(uri)
        .map_err(|e| {
            warn!("Failed to GET {}: {}", uri, e);
            CliError::BackendFailure("No version information found on API".into())
        })?;
    trace!("Got body {}", resp);

    let res: ArtifactoryStorageResponse = serde_json::from_str(&resp)?;
    let latest: Option<Version> = res.children
        .iter()
        .map(|r| r.uri.trim_matches('/').to_string())
        .inspect(|v| trace!("Found lal version {}", v))
        .filter_map(|v| Version::parse(&v).ok())
        .max(); // Semver::Version implements an order

    if let Some(l) = latest {
        Ok(LatestLal {
               version: l.clone(),
               url: format!("https://engci-maven.cisco.com/artifactory/CME-group/lal/{}/lal.tar",
                            l),
           })
    } else {
        warn!("Failed to parse version information from artifactory storage api for lal");
        Err(CliError::BackendFailure("No version information found on API".into()))
    }
}

use super::{Backend, Component};

/// Everything we need for Artifactory to implement the Backend trait
pub struct ArtifactoryBackend {
    /// Artifactory config and credentials
    pub config: ArtifactoryConfig,
    /// Cache directory
    pub cache: String,
}

impl ArtifactoryBackend {
    pub fn new(cfg: &ArtifactoryConfig, cache: &str) -> Self {
        // TODO: create hyper clients in here rather than once per download
        ArtifactoryBackend {
            config: cfg.clone(),
            cache: cache.into(),
        }
    }
}

/// Artifact backend trait for `ArtifactoryBackend`
///
/// This is intended to be used by the caching trait `CachedBackend`, but for
/// specific low-level use cases, these methods can be used directly.
impl Backend for ArtifactoryBackend {
    fn get_versions(&self, name: &str, loc: Option<&str>) -> LalResult<Vec<u32>> {
        get_latest_versions(&self.config, name, loc)
    }

    fn get_latest_version(&self, name: &str, loc: Option<&str>) -> LalResult<u32> {
        let latest = get_dependency_url_latest(&self.config, name, loc)?;
        Ok(latest.version)
    }

    fn get_tarball_url(
        &self,
        name: &str,
        version: Option<u32>,
        loc: Option<&str>,
    ) -> LalResult<Component> {
        get_tarball_uri(&self.config, name, version, loc)
    }

    fn upload_artifact_dir(&self, name: &str, version: u32, env: Option<&str>) -> LalResult<()> {
        // this fn basically assumes all the sanity checks have been performed
        // files must exist and lockfile must be sensible
        let artdir = Path::new("./ARTIFACT");
        let tarball = artdir.join(format!("{}.tar.gz", name));
        let lockfile = artdir.join("lockfile.json");

        // uri prefix if specific env upload
        let prefix = env.map(|s| format!("env/{}/", s)).unwrap_or_else(|| "".into());

        let tar_uri = format!("{}{}/{}/{}.tar.gz", prefix, name, version, name);
        let mut tarf = File::open(tarball)?;
        upload_artifact(&self.config, &tar_uri, &mut tarf)?;

        let mut lockf = File::open(lockfile)?;
        let lf_uri = format!("{}{}/{}/lockfile.json", prefix, name, version);
        upload_artifact(&self.config, &lf_uri, &mut lockf)?;
        Ok(())
    }

    fn get_cache_dir(&self) -> String { self.cache.clone() }

    fn raw_download(&self, url: &str, dest: &PathBuf) -> LalResult<()> {
        http_download_to_path(url, dest)
    }
}