httpcan 0.8.1

use super::*;
use actix_web::{body::SizedStream, web::Bytes, HttpResponseBuilder};
use rand::rngs::StdRng;
use rand::{RngExt, SeedableRng};
use std::time::Duration;
use tokio::time::sleep;

#[derive(Deserialize)]
pub struct DripQuery {
    duration: Option<f64>,
    numbytes: Option<usize>,
    code: Option<u16>,
    delay: Option<f64>,
    chunked: Option<bool>,
}

#[derive(Deserialize)]
pub struct BytesQuery {
    seed: Option<u64>,
}

#[derive(Deserialize)]
pub struct StreamBytesQuery {
    seed: Option<u64>,
    chunk_size: Option<usize>,
}

#[derive(Deserialize)]
pub struct RangeQuery {
    chunk_size: Option<usize>,
    duration: Option<f64>,
}

// Helper function to parse Range header - mimics httpbin's __parse_request_range
fn parse_request_range(range_header_value: &str) -> (Option<usize>, Option<usize>) {
    if !range_header_value.starts_with("bytes=") {
        return (None, None);
    }

    let range_part = &range_header_value[6..];

    // Handle multiple ranges (take first one like httpbin)
    let first_range = range_part.split(',').next().unwrap_or(range_part);

    if let Some((start_str, end_str)) = first_range.split_once('-') {
        let first_byte_pos = if start_str.is_empty() {
            None
        } else {
            start_str.parse().ok()
        };

        let last_byte_pos = if end_str.is_empty() {
            None
        } else {
            end_str.parse().ok()
        };

        return (first_byte_pos, last_byte_pos);
    }

    (None, None)
}

// Helper function to get request range - mimics httpbin's get_request_range
fn get_request_range(req: &HttpRequest, upper_bound: usize) -> (usize, usize) {
    let (first_byte_pos, last_byte_pos) = if let Some(range_header) = req.headers().get("Range") {
        if let Ok(range_str) = range_header.to_str() {
            parse_request_range(range_str)
        } else {
            (None, None)
        }
    } else {
        (None, None)
    };

    let (first_byte_pos, last_byte_pos) = match (first_byte_pos, last_byte_pos) {
        (None, None) => {
            // Request full range
            (0, upper_bound - 1)
        }
        (None, Some(suffix_length)) => {
            // Request the last X bytes (suffix-byte-range-spec: "-500")
            let first_pos = upper_bound.saturating_sub(suffix_length);
            (first_pos, upper_bound - 1)
        }
        (Some(start), None) => {
            // Request from X to end
            (start, upper_bound - 1)
        }
        (Some(start), Some(end)) => {
            // Request specific range
            (start, end)
        }
    };

    (first_byte_pos, last_byte_pos)
}

pub async fn uuid_handler(_req: HttpRequest) -> Result<HttpResponse> {
    let uuid = Uuid::new_v4();
    Ok(HttpResponse::Ok().json(json!({
        "uuid": uuid.to_string()
    })))
}

pub async fn base64_handler(_req: HttpRequest, path: web::Path<String>) -> Result<HttpResponse> {
    let encoded_value = path.into_inner();

    match general_purpose::STANDARD.decode(&encoded_value) {
        Ok(decoded_bytes) => match String::from_utf8(decoded_bytes) {
            Ok(decoded_string) => Ok(HttpResponse::Ok()
                .content_type("text/plain; charset=utf-8")
                .body(decoded_string)),
            Err(e) => Ok(HttpResponse::Ok()
                .content_type("application/octet-stream")
                .body(e.into_bytes())),
        },
        Err(_) => Ok(HttpResponse::BadRequest().json(json!({
            "error": "Invalid base64 data"
        }))),
    }
}

/// POST /base64 - decode the base64 request body and return it as text/plain (httpbin #616).
pub async fn base64_post_handler(body: web::Bytes) -> Result<HttpResponse> {
    match general_purpose::STANDARD.decode(&body) {
        Ok(decoded_bytes) => match String::from_utf8(decoded_bytes) {
            Ok(decoded_string) => Ok(HttpResponse::Ok()
                .content_type("text/plain; charset=utf-8")
                .body(decoded_string)),
            Err(e) => Ok(HttpResponse::Ok()
                .content_type("application/octet-stream")
                .body(e.into_bytes())),
        },
        Err(_) => Ok(HttpResponse::BadRequest().json(json!({
            "error": "Invalid base64 data"
        }))),
    }
}

pub async fn bytes_handler(
    _req: HttpRequest,
    path: web::Path<usize>,
    query: web::Query<BytesQuery>,
    config: web::Data<AppConfig>,
) -> Result<HttpResponse> {
    let n = path.into_inner();
    // httpbin #594: reject over-limit requests with a clear error instead of
    // silently truncating, consistent with /range/{numbytes}.
    if n > config.max_bytes {
        return Ok(HttpResponse::NotFound().body(format!(
            "number of bytes must be in the range (0, {}]",
            config.max_bytes
        )));
    }

    // Generate random bytes using the same method as httpbin
    let random_bytes: Vec<u8> = if let Some(seed) = query.seed {
        let mut rng = StdRng::seed_from_u64(seed);
        (0..n).map(|_| rng.random_range(0..=255)).collect()
    } else {
        let mut rng = rand::rng();
        (0..n).map(|_| rng.random_range(0..=255)).collect()
    };

    Ok(HttpResponse::Ok()
        .content_type("application/octet-stream")
        .body(random_bytes))
}

pub async fn stream_bytes_handler(
    _req: HttpRequest,
    path: web::Path<usize>,
    query: web::Query<StreamBytesQuery>,
    config: web::Data<AppConfig>,
) -> Result<HttpResponse> {
    let n = path.into_inner();
    // httpbin #594: reject over-limit requests with a clear error instead of
    // silently truncating, consistent with /range/{numbytes}.
    if n > config.max_bytes {
        return Ok(HttpResponse::NotFound().body(format!(
            "number of bytes must be in the range (0, {}]",
            config.max_bytes
        )));
    }

    // Parse chunk_size parameter
    let chunk_size = query.chunk_size.unwrap_or(10 * 1024).max(1);

    // Initialize RNG with seed if provided
    let seed = query.seed;

    let stream = async_stream::stream! {
        let mut chunks = Vec::new();

        if let Some(seed) = seed {
            let mut rng = StdRng::seed_from_u64(seed);
            for _ in 0..n {
                chunks.push(rng.random_range(0..=255));

                if chunks.len() == chunk_size {
                    yield Ok::<_, actix_web::Error>(Bytes::from(chunks.clone()));
                    chunks.clear();
                }
            }
        } else {
            let mut rng = rand::rng();
            for _ in 0..n {
                chunks.push(rng.random_range(0..=255));

                if chunks.len() == chunk_size {
                    yield Ok::<_, actix_web::Error>(Bytes::from(chunks.clone()));
                    chunks.clear();
                }
            }
        }

        // Yield remaining bytes if any
        if !chunks.is_empty() {
            yield Ok::<_, actix_web::Error>(Bytes::from(chunks));
        }
    };

    Ok(HttpResponse::Ok()
        .content_type("application/octet-stream")
        .streaming(stream))
}

pub async fn stream_handler(
    req: HttpRequest,
    path: web::Path<usize>,
    config: web::Data<AppConfig>,
) -> Result<HttpResponse> {
    let n = path.into_inner();
    let n = n.min(100); // Limit to 100 lines

    // Extract request information similar to httpbin's get_dict("url", "args", "headers", "origin")
    let base_response = extract_get_request_info(&req, &config.exclude_headers);

    let stream = futures_util::stream::iter((0..n).map(move |i| {
        let response = json!({
            "url": base_response.url,
            "args": base_response.args,
            "headers": base_response.headers,
            "origin": base_response.origin,
            "id": i
        });

        // Format as JSON string with newline, matching httpbin's json.dumps(response) + "\n"
        Ok::<_, actix_web::Error>(Bytes::from(format!("{}\n", response)))
    }));

    Ok(HttpResponse::Ok()
        .content_type("application/json")
        .streaming(stream))
}

pub async fn range_handler(
    req: HttpRequest,
    path: web::Path<usize>,
    query: web::Query<RangeQuery>,
    config: web::Data<AppConfig>,
) -> Result<HttpResponse> {
    let numbytes = path.into_inner();

    // Check bounds first like httpbin; the cap is the configured --max-bytes
    // (httpbin #594), consistent with /bytes and /stream-bytes.
    if numbytes == 0 || numbytes > config.max_bytes {
        return Ok(HttpResponse::NotFound()
            .append_header(("ETag", format!("range{}", numbytes)))
            .append_header(("Accept-Ranges", "bytes"))
            .body(format!(
                "number of bytes must be in the range (0, {}]",
                config.max_bytes
            )));
    }

    let chunk_size = query.chunk_size.unwrap_or(10 * 1024).max(1);
    let duration = query.duration.unwrap_or(0.0);

    // Extract range information from headers using httpbin-compatible logic
    let (first_byte_pos, last_byte_pos) = get_request_range(&req, numbytes);

    // Validate range like httpbin
    if first_byte_pos > last_byte_pos || first_byte_pos >= numbytes || last_byte_pos >= numbytes {
        return Ok(HttpResponse::RangeNotSatisfiable()
            .append_header(("ETag", format!("range{}", numbytes)))
            .append_header(("Accept-Ranges", "bytes"))
            .append_header(("Content-Range", format!("bytes */{}", numbytes)))
            .append_header(("Content-Length", "0"))
            .finish());
    }

    let range_length = (last_byte_pos + 1) - first_byte_pos;
    let pause_per_byte = if range_length > 0 {
        Duration::from_secs_f64(duration / range_length as f64)
    } else {
        Duration::ZERO
    };

    // Create streaming response
    let stream = async_stream::stream! {
        let mut chunks = Vec::new();

        for i in first_byte_pos..=last_byte_pos {
            // Use deterministic data generation like httpbin: ord("a") + (i % 26)
            // This ensures consistent data for the same byte position across requests
            chunks.push(b'a' + (i % 26) as u8);

            if chunks.len() == chunk_size || i == last_byte_pos {
                yield Ok::<_, actix_web::Error>(Bytes::from(chunks.clone()));

                // Apply timing delay if specified
                if pause_per_byte.as_nanos() > 0 && !chunks.is_empty() {
                    tokio::time::sleep(pause_per_byte * chunks.len() as u32).await;
                }

                chunks.clear();
            }
        }
    };

    let content_range = format!("bytes {}-{}/{}", first_byte_pos, last_byte_pos, numbytes);

    // Determine status code: 200 for full content, 206 for partial content
    let is_full_content = first_byte_pos == 0 && last_byte_pos == (numbytes - 1);
    let status = if is_full_content {
        StatusCode::OK
    } else {
        StatusCode::PARTIAL_CONTENT
    };

    Ok(HttpResponseBuilder::new(status)
        .content_type("application/octet-stream")
        .append_header(("ETag", format!("range{}", numbytes)))
        .append_header(("Accept-Ranges", "bytes"))
        .append_header(("Content-Length", range_length.to_string()))
        .append_header(("Content-Range", content_range))
        .body(SizedStream::new(range_length as u64, Box::pin(stream))))
}

pub async fn links_handler(
    _req: HttpRequest,
    path: web::Path<(usize, usize)>,
) -> Result<HttpResponse> {
    let (n, offset) = path.into_inner();
    let n = n.clamp(1, 200); // Limit to between 1 and 200 links

    let mut html = String::from("<!DOCTYPE html><html><head><title>Links</title></head><body>");

    for i in 0..n {
        if i == offset {
            html.push_str(&format!("{}<br>", i));
        } else {
            html.push_str(&format!("<a href='/links/{}/{}'>{}</a><br>", n, i, i));
        }
    }

    html.push_str("</body></html>");

    Ok(HttpResponse::Ok().content_type("text/html").body(html))
}

pub async fn links_redirect_handler(
    _req: HttpRequest,
    path: web::Path<usize>,
) -> Result<HttpResponse> {
    let n = path.into_inner();
    Ok(HttpResponse::Found()
        .append_header(("Location", format!("/links/{}/0", n)))
        .body(""))
}

pub async fn drip_handler(
    _req: HttpRequest,
    query: web::Query<DripQuery>,
    config: web::Data<AppConfig>,
) -> Result<HttpResponse> {
    let duration = query.duration.unwrap_or(2.0);
    let numbytes = query.numbytes.unwrap_or(10);
    let code = query.code.unwrap_or(200);
    let delay = query.delay.unwrap_or(0.0);

    // Validate parameters
    if numbytes == 0 {
        return Ok(HttpResponse::BadRequest().json(json!({
            "error": "number of bytes must be positive"
        })));
    }

    // Reject over-limit requests with a clear error instead of silently
    // clamping, consistent with /bytes, /stream-bytes, and /range (httpbin #594).
    if numbytes > config.max_bytes {
        return Ok(HttpResponse::NotFound().json(json!({
            "error": format!("number of bytes must be in the range (0, {}]", config.max_bytes)
        })));
    }

    // Validate status code
    let status = StatusCode::from_u16(code).unwrap_or(StatusCode::OK);

    // Initial delay
    if delay > 0.0 {
        sleep(Duration::from_secs_f64(delay)).await;
    }

    // Calculate pause between bytes
    let pause = if numbytes == 1 {
        Duration::from_secs_f64(duration)
    } else {
        Duration::from_secs_f64(duration / (numbytes as f64 - 1.0))
    };

    // Create streaming response
    let stream = async_stream::stream! {
        for i in 0..numbytes {
            // Yield a single '*' byte
            yield Ok::<_, actix_web::Error>(Bytes::from("*"));

            // Don't pause after the last byte
            if i < numbytes - 1 && pause.as_nanos() > 0 {
                sleep(pause).await;
            }
        }
    };

    let mut builder = HttpResponseBuilder::new(status);
    builder.content_type("application/octet-stream");
    // Chunked transfer-encoding (no Content-Length) when requested (httpbin #479);
    // otherwise SizedStream sets Content-Length.
    let response = if query.chunked.unwrap_or(false) {
        builder.streaming(stream)
    } else {
        builder.body(SizedStream::new(numbytes as u64, Box::pin(stream)))
    };
    Ok(response)
}

pub async fn delay_handler_get(
    req: HttpRequest,
    path: web::Path<f64>,
    config: web::Data<AppConfig>,
) -> Result<HttpResponse> {
    let delay_seconds = path.into_inner().min(10.0); // Max 10 seconds

    sleep(Duration::from_secs_f64(delay_seconds)).await;

    let mut request_info = extract_request_info(&req, None, &config.exclude_headers);
    fix_request_info_url(&req, &mut request_info);
    Ok(HttpResponse::Ok().json(request_info))
}

pub async fn delay_handler(
    req: HttpRequest,
    path: web::Path<f64>,
    body: String,
    config: web::Data<AppConfig>,
) -> Result<HttpResponse> {
    let delay_seconds = path.into_inner().min(10.0); // Max 10 seconds

    sleep(Duration::from_secs_f64(delay_seconds)).await;

    let mut request_info = extract_request_info(&req, Some(&body), &config.exclude_headers);
    fix_request_info_url(&req, &mut request_info);
    Ok(HttpResponse::Ok().json(request_info))
}