// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements.  See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership.  The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License.  You may obtain a copy of the License at
//
//   http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied.  See the License for the
// specific language governing permissions and limitations
// under the License.

//! An object store implementation for Google Cloud Storage
//!
//! ## Multipart uploads
//!
//! [Multipart uploads](https://cloud.google.com/storage/docs/multipart-uploads)
//! can be initiated with the [ObjectStore::put_multipart] method. If neither
//! [`MultipartUpload::complete`] nor [`MultipartUpload::abort`] is invoked, you may
//! have parts uploaded to GCS but not used, that you will be charged for. It is recommended
//! you configure a [lifecycle rule] to abort incomplete multipart uploads after a certain
//! period of time to avoid being charged for storing partial uploads.
//!
//! ## Using HTTP/2
//!
//! Google Cloud Storage supports both HTTP/2 and HTTP/1. HTTP/1 is used by default
//! because it allows much higher throughput in our benchmarks (see
//! [#5194](https://github.com/apache/arrow-rs/issues/5194)). HTTP/2 can be
//! enabled by setting [crate::ClientConfigKey::Http1Only] to false.
//!
//! [lifecycle rule]: https://cloud.google.com/storage/docs/lifecycle#abort-mpu
use std::sync::Arc;
use std::time::Duration;

use crate::client::CredentialProvider;
use crate::gcp::credential::GCSAuthorizer;
use crate::signer::Signer;
use crate::{
    multipart::PartId, path::Path, GetOptions, GetResult, ListResult, MultipartId, MultipartUpload,
    ObjectMeta, ObjectStore, PutMultipartOpts, PutOptions, PutPayload, PutResult, Result,
    UploadPart,
};
use async_trait::async_trait;
use client::GoogleCloudStorageClient;
use futures::stream::BoxStream;
use hyper::Method;
use url::Url;

use crate::client::get::GetClientExt;
use crate::client::list::ListClientExt;
use crate::client::parts::Parts;
use crate::multipart::MultipartStore;
pub use builder::{GoogleCloudStorageBuilder, GoogleConfigKey};
pub use credential::{GcpCredential, GcpSigningCredential, ServiceAccountKey};

mod builder;
mod client;
mod credential;

const STORE: &str = "GCS";

/// [`CredentialProvider`] for [`GoogleCloudStorage`]
pub type GcpCredentialProvider = Arc<dyn CredentialProvider<Credential = GcpCredential>>;

/// [`GcpSigningCredential`] for [`GoogleCloudStorage`]
pub type GcpSigningCredentialProvider =
    Arc<dyn CredentialProvider<Credential = GcpSigningCredential>>;

/// Interface for [Google Cloud Storage](https://cloud.google.com/storage/).
#[derive(Debug)]
pub struct GoogleCloudStorage {
    client: Arc<GoogleCloudStorageClient>,
}

impl std::fmt::Display for GoogleCloudStorage {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        write!(
            f,
            "GoogleCloudStorage({})",
            self.client.config().bucket_name
        )
    }
}

impl GoogleCloudStorage {
    /// Returns the [`GcpCredentialProvider`] used by [`GoogleCloudStorage`]
    pub fn credentials(&self) -> &GcpCredentialProvider {
        &self.client.config().credentials
    }

    /// Returns the [`GcpSigningCredentialProvider`] used by [`GoogleCloudStorage`]
    pub fn signing_credentials(&self) -> &GcpSigningCredentialProvider {
        &self.client.config().signing_credentials
    }
}

#[derive(Debug)]
struct GCSMultipartUpload {
    state: Arc<UploadState>,
    part_idx: usize,
}

#[derive(Debug)]
struct UploadState {
    client: Arc<GoogleCloudStorageClient>,
    path: Path,
    multipart_id: MultipartId,
    parts: Parts,
}

#[async_trait]
impl MultipartUpload for GCSMultipartUpload {
    fn put_part(&mut self, payload: PutPayload) -> UploadPart {
        let idx = self.part_idx;
        self.part_idx += 1;
        let state = Arc::clone(&self.state);
        Box::pin(async move {
            let part = state
                .client
                .put_part(&state.path, &state.multipart_id, idx, payload)
                .await?;
            state.parts.put(idx, part);
            Ok(())
        })
    }

    async fn complete(&mut self) -> Result<PutResult> {
        let parts = self.state.parts.finish(self.part_idx)?;

        self.state
            .client
            .multipart_complete(&self.state.path, &self.state.multipart_id, parts)
            .await
    }

    async fn abort(&mut self) -> Result<()> {
        self.state
            .client
            .multipart_cleanup(&self.state.path, &self.state.multipart_id)
            .await
    }
}

#[async_trait]
impl ObjectStore for GoogleCloudStorage {
    async fn put_opts(
        &self,
        location: &Path,
        payload: PutPayload,
        opts: PutOptions,
    ) -> Result<PutResult> {
        self.client.put(location, payload, opts).await
    }

    async fn put_multipart_opts(
        &self,
        location: &Path,
        opts: PutMultipartOpts,
    ) -> Result<Box<dyn MultipartUpload>> {
        let upload_id = self.client.multipart_initiate(location, opts).await?;

        Ok(Box::new(GCSMultipartUpload {
            part_idx: 0,
            state: Arc::new(UploadState {
                client: Arc::clone(&self.client),
                path: location.clone(),
                multipart_id: upload_id.clone(),
                parts: Default::default(),
            }),
        }))
    }

    async fn get_opts(&self, location: &Path, options: GetOptions) -> Result<GetResult> {
        self.client.get_opts(location, options).await
    }

    async fn delete(&self, location: &Path) -> Result<()> {
        self.client.delete_request(location).await
    }

    fn list(&self, prefix: Option<&Path>) -> BoxStream<'_, Result<ObjectMeta>> {
        self.client.list(prefix)
    }

    fn list_with_offset(
        &self,
        prefix: Option<&Path>,
        offset: &Path,
    ) -> BoxStream<'_, Result<ObjectMeta>> {
        self.client.list_with_offset(prefix, offset)
    }

    async fn list_with_delimiter(&self, prefix: Option<&Path>) -> Result<ListResult> {
        self.client.list_with_delimiter(prefix).await
    }

    async fn copy(&self, from: &Path, to: &Path) -> Result<()> {
        self.client.copy_request(from, to, false).await
    }

    async fn copy_if_not_exists(&self, from: &Path, to: &Path) -> Result<()> {
        self.client.copy_request(from, to, true).await
    }
}

#[async_trait]
impl MultipartStore for GoogleCloudStorage {
    async fn create_multipart(&self, path: &Path) -> Result<MultipartId> {
        self.client
            .multipart_initiate(path, PutMultipartOpts::default())
            .await
    }

    async fn put_part(
        &self,
        path: &Path,
        id: &MultipartId,
        part_idx: usize,
        payload: PutPayload,
    ) -> Result<PartId> {
        self.client.put_part(path, id, part_idx, payload).await
    }

    async fn complete_multipart(
        &self,
        path: &Path,
        id: &MultipartId,
        parts: Vec<PartId>,
    ) -> Result<PutResult> {
        self.client.multipart_complete(path, id, parts).await
    }

    async fn abort_multipart(&self, path: &Path, id: &MultipartId) -> Result<()> {
        self.client.multipart_cleanup(path, id).await
    }
}

#[async_trait]
impl Signer for GoogleCloudStorage {
    async fn signed_url(&self, method: Method, path: &Path, expires_in: Duration) -> Result<Url> {
        if expires_in.as_secs() > 604800 {
            return Err(crate::Error::Generic {
                store: STORE,
                source: "Expiration Time can't be longer than 604800 seconds (7 days).".into(),
            });
        }

        let config = self.client.config();
        let path_url = config.path_url(path);
        let mut url = Url::parse(&path_url).map_err(|e| crate::Error::Generic {
            store: STORE,
            source: format!("Unable to parse url {path_url}: {e}").into(),
        })?;

        let signing_credentials = self.signing_credentials().get_credential().await?;
        let authorizer = GCSAuthorizer::new(signing_credentials);

        authorizer
            .sign(method, &mut url, expires_in, &self.client)
            .await?;

        Ok(url)
    }
}

#[cfg(test)]
mod test {

    use credential::DEFAULT_GCS_BASE_URL;

    use crate::integration::*;
    use crate::tests::*;

    use super::*;

    const NON_EXISTENT_NAME: &str = "nonexistentname";

    #[tokio::test]
    async fn gcs_test() {
        maybe_skip_integration!();
        let integration = GoogleCloudStorageBuilder::from_env().build().unwrap();

        put_get_delete_list(&integration).await;
        list_uses_directories_correctly(&integration).await;
        list_with_delimiter(&integration).await;
        rename_and_copy(&integration).await;
        if integration.client.config().base_url == DEFAULT_GCS_BASE_URL {
            // Fake GCS server doesn't currently honor ifGenerationMatch
            // https://github.com/fsouza/fake-gcs-server/issues/994
            copy_if_not_exists(&integration).await;
            // Fake GCS server does not yet implement XML Multipart uploads
            // https://github.com/fsouza/fake-gcs-server/issues/852
            stream_get(&integration).await;
            multipart(&integration, &integration).await;
            // Fake GCS server doesn't currently honor preconditions
            get_opts(&integration).await;
            put_opts(&integration, true).await;
            // Fake GCS server doesn't currently support attributes
            put_get_attributes(&integration).await;
        }
    }

    #[tokio::test]
    #[ignore]
    async fn gcs_test_sign() {
        maybe_skip_integration!();
        let integration = GoogleCloudStorageBuilder::from_env().build().unwrap();

        let client = reqwest::Client::new();

        let path = Path::from("test_sign");
        let url = integration
            .signed_url(Method::PUT, &path, Duration::from_secs(3600))
            .await
            .unwrap();
        println!("PUT {url}");

        let resp = client.put(url).body("data").send().await.unwrap();
        resp.error_for_status().unwrap();

        let url = integration
            .signed_url(Method::GET, &path, Duration::from_secs(3600))
            .await
            .unwrap();
        println!("GET {url}");

        let resp = client.get(url).send().await.unwrap();
        let resp = resp.error_for_status().unwrap();
        let data = resp.bytes().await.unwrap();
        assert_eq!(data.as_ref(), b"data");
    }

    #[tokio::test]
    async fn gcs_test_get_nonexistent_location() {
        maybe_skip_integration!();
        let integration = GoogleCloudStorageBuilder::from_env().build().unwrap();

        let location = Path::from_iter([NON_EXISTENT_NAME]);

        let err = integration.get(&location).await.unwrap_err();

        assert!(
            matches!(err, crate::Error::NotFound { .. }),
            "unexpected error type: {err}"
        );
    }

    #[tokio::test]
    async fn gcs_test_get_nonexistent_bucket() {
        maybe_skip_integration!();
        let config = GoogleCloudStorageBuilder::from_env();
        let integration = config.with_bucket_name(NON_EXISTENT_NAME).build().unwrap();

        let location = Path::from_iter([NON_EXISTENT_NAME]);

        let err = get_nonexistent_object(&integration, Some(location))
            .await
            .unwrap_err();

        assert!(
            matches!(err, crate::Error::NotFound { .. }),
            "unexpected error type: {err}"
        );
    }

    #[tokio::test]
    async fn gcs_test_delete_nonexistent_location() {
        maybe_skip_integration!();
        let integration = GoogleCloudStorageBuilder::from_env().build().unwrap();

        let location = Path::from_iter([NON_EXISTENT_NAME]);

        let err = integration.delete(&location).await.unwrap_err();
        assert!(
            matches!(err, crate::Error::NotFound { .. }),
            "unexpected error type: {err}"
        );
    }

    #[tokio::test]
    async fn gcs_test_delete_nonexistent_bucket() {
        maybe_skip_integration!();
        let config = GoogleCloudStorageBuilder::from_env();
        let integration = config.with_bucket_name(NON_EXISTENT_NAME).build().unwrap();

        let location = Path::from_iter([NON_EXISTENT_NAME]);

        let err = integration.delete(&location).await.unwrap_err();
        assert!(
            matches!(err, crate::Error::NotFound { .. }),
            "unexpected error type: {err}"
        );
    }

    #[tokio::test]
    async fn gcs_test_put_nonexistent_bucket() {
        maybe_skip_integration!();
        let config = GoogleCloudStorageBuilder::from_env();
        let integration = config.with_bucket_name(NON_EXISTENT_NAME).build().unwrap();

        let location = Path::from_iter([NON_EXISTENT_NAME]);
        let data = PutPayload::from("arbitrary data");

        let err = integration
            .put(&location, data)
            .await
            .unwrap_err()
            .to_string();
        assert!(
            err.contains("Client error with status 404 Not Found"),
            "{}",
            err
        )
    }
}