// Copyright (c) 2026 Volkov Pavel | DevITWay
// SPDX-License-Identifier: MIT

use crate::activity_log::{ActionType, ActivityEntry};
use crate::audit::AuditEntry;
use crate::config::basic_auth_header;
use crate::AppState;
use axum::{
    body::Bytes,
    extract::{Path, State},
    http::{header, StatusCode},
    response::{IntoResponse, Response},
    routing::{get, put},
    Router,
};
use std::sync::Arc;
use std::time::Duration;

pub fn routes() -> Router<Arc<AppState>> {
    Router::new()
        .route("/maven2/{*path}", get(download))
        .route("/maven2/{*path}", put(upload))
}

async fn download(State(state): State<Arc<AppState>>, Path(path): Path<String>) -> Response {
    let key = format!("maven/{}", path);

    let artifact_name = path
        .split('/')
        .rev()
        .take(3)
        .collect::<Vec<_>>()
        .into_iter()
        .rev()
        .collect::<Vec<_>>()
        .join("/");

    if let Ok(data) = state.storage.get(&key).await {
        state.metrics.record_download("maven");
        state.metrics.record_cache_hit();
        state.activity.push(ActivityEntry::new(
            ActionType::CacheHit,
            artifact_name,
            "maven",
            "CACHE",
        ));
        state
            .audit
            .log(AuditEntry::new("cache_hit", "api", "", "maven", ""));
        return with_content_type(&path, data).into_response();
    }

    for proxy in &state.config.maven.proxies {
        let url = format!("{}/{}", proxy.url().trim_end_matches('/'), path);

        match fetch_from_proxy(
            &state.http_client,
            &url,
            state.config.maven.proxy_timeout,
            proxy.auth(),
        )
        .await
        {
            Ok(data) => {
                state.metrics.record_download("maven");
                state.metrics.record_cache_miss();
                state.activity.push(ActivityEntry::new(
                    ActionType::ProxyFetch,
                    artifact_name,
                    "maven",
                    "PROXY",
                ));
                state
                    .audit
                    .log(AuditEntry::new("proxy_fetch", "api", "", "maven", ""));

                let storage = state.storage.clone();
                let key_clone = key.clone();
                let data_clone = data.clone();
                tokio::spawn(async move {
                    let _ = storage.put(&key_clone, &data_clone).await;
                });

                state.repo_index.invalidate("maven");

                return with_content_type(&path, data.into()).into_response();
            }
            Err(_) => continue,
        }
    }

    StatusCode::NOT_FOUND.into_response()
}

async fn upload(
    State(state): State<Arc<AppState>>,
    Path(path): Path<String>,
    body: Bytes,
) -> StatusCode {
    let key = format!("maven/{}", path);

    let artifact_name = path
        .split('/')
        .rev()
        .take(3)
        .collect::<Vec<_>>()
        .into_iter()
        .rev()
        .collect::<Vec<_>>()
        .join("/");

    match state.storage.put(&key, &body).await {
        Ok(()) => {
            state.metrics.record_upload("maven");
            state.activity.push(ActivityEntry::new(
                ActionType::Push,
                artifact_name,
                "maven",
                "LOCAL",
            ));
            state
                .audit
                .log(AuditEntry::new("push", "api", "", "maven", ""));
            state.repo_index.invalidate("maven");
            StatusCode::CREATED
        }
        Err(_) => StatusCode::INTERNAL_SERVER_ERROR,
    }
}

async fn fetch_from_proxy(
    client: &reqwest::Client,
    url: &str,
    timeout_secs: u64,
    auth: Option<&str>,
) -> Result<Vec<u8>, ()> {
    let mut request = client.get(url).timeout(Duration::from_secs(timeout_secs));
    if let Some(credentials) = auth {
        request = request.header("Authorization", basic_auth_header(credentials));
    }
    let response = request.send().await.map_err(|_| ())?;

    if !response.status().is_success() {
        return Err(());
    }

    response.bytes().await.map(|b| b.to_vec()).map_err(|_| ())
}

fn with_content_type(
    path: &str,
    data: Bytes,
) -> (StatusCode, [(header::HeaderName, &'static str); 1], Bytes) {
    let content_type = if path.ends_with(".pom") {
        "application/xml"
    } else if path.ends_with(".jar") {
        "application/java-archive"
    } else if path.ends_with(".xml") {
        "application/xml"
    } else if path.ends_with(".sha1") || path.ends_with(".md5") {
        "text/plain"
    } else {
        "application/octet-stream"
    };

    (StatusCode::OK, [(header::CONTENT_TYPE, content_type)], data)
}