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// 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.

use std::fmt::Debug;

use serde::Deserialize;
use serde::Serialize;

use super::D1_SCHEME;
use super::backend::D1Builder;

/// Config for [Cloudflare D1](https://developers.cloudflare.com/d1) backend support.
#[derive(Default, Serialize, Deserialize, Clone, PartialEq, Eq)]
#[serde(default)]
#[non_exhaustive]
pub struct D1Config {
    /// Set the token of cloudflare api.
    pub token: Option<String>,
    /// Set the account id of cloudflare api.
    pub account_id: Option<String>,
    /// Set the database id of cloudflare api.
    pub database_id: Option<String>,

    /// Set the working directory of OpenDAL.
    pub root: Option<String>,
    /// Set the table of D1 Database.
    pub table: Option<String>,
    /// Set the key field of D1 Database.
    pub key_field: Option<String>,
    /// Set the value field of D1 Database.
    pub value_field: Option<String>,
}

impl Debug for D1Config {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        f.debug_struct("D1Config")
            .field("root", &self.root)
            .field("table", &self.table)
            .field("key_field", &self.key_field)
            .field("value_field", &self.value_field)
            .finish_non_exhaustive()
    }
}

impl opendal_core::Configurator for D1Config {
    type Builder = D1Builder;

    fn from_uri(uri: &opendal_core::OperatorUri) -> opendal_core::Result<Self> {
        let account_id = uri.name().ok_or_else(|| {
            opendal_core::Error::new(
                opendal_core::ErrorKind::ConfigInvalid,
                "uri host must contain account id",
            )
            .with_context("service", D1_SCHEME)
        })?;

        let database_and_root = uri.root().ok_or_else(|| {
            opendal_core::Error::new(
                opendal_core::ErrorKind::ConfigInvalid,
                "uri path must contain database id",
            )
            .with_context("service", D1_SCHEME)
        })?;

        let mut segments = database_and_root.splitn(2, '/');
        let database_id = segments.next().filter(|s| !s.is_empty()).ok_or_else(|| {
            opendal_core::Error::new(
                opendal_core::ErrorKind::ConfigInvalid,
                "database id is required in uri path",
            )
            .with_context("service", D1_SCHEME)
        })?;

        let mut map = uri.options().clone();
        map.insert("account_id".to_string(), account_id.to_string());
        map.insert("database_id".to_string(), database_id.to_string());

        if let Some(rest) = segments.next() {
            if !rest.is_empty() {
                map.insert("root".to_string(), rest.to_string());
            }
        }

        Self::from_iter(map)
    }

    fn into_builder(self) -> Self::Builder {
        D1Builder { config: self }
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use opendal_core::Configurator;
    use opendal_core::OperatorUri;

    #[test]
    fn from_uri_sets_account_database_and_root() {
        let uri =
            OperatorUri::new("d1://acc123/db456/cache", Vec::<(String, String)>::new()).unwrap();

        let cfg = D1Config::from_uri(&uri).unwrap();
        assert_eq!(cfg.account_id.as_deref(), Some("acc123"));
        assert_eq!(cfg.database_id.as_deref(), Some("db456"));
        assert_eq!(cfg.root.as_deref(), Some("cache"));
    }
}
