use actix_web::error::ErrorNotFound;
use actix_web::{HttpRequest, HttpResponse, Result, error::ErrorInternalServerError, web};
use log::{error, info, warn};

use super::common::{
    create_file_response_with_analytics, create_vercel_compatible_response, is_vercel_request,
};
use crate::app_state::AppState;
use crate::handlers::serve_file::serve_file;
use crate::lookup::{find_file_by_pattern, get_mime_type};
use crate::s3_utils::{check_file_exists, load_file_from_s3, upload_to_s3};
use crate::thumbnail::parse_file_path;

// Удалена дублирующая функция, используется из common модуля

/// Обработчик для скачивания файла
/// без генерации миниатюр - это делает Vercel Edge API
#[allow(clippy::collapsible_if)]
pub async fn proxy_handler(
    req: HttpRequest,
    requested_res: web::Path<String>,
    state: web::Data<AppState>,
) -> Result<HttpResponse, actix_web::Error> {
    let start_time = std::time::Instant::now();
    info!("GET {} [START]", requested_res);

    let normalized_path = if requested_res.ends_with("/webp") {
        info!("Converting to WebP format: {}", requested_res);
        requested_res.replace("/webp", "")
    } else {
        requested_res.to_string()
    };

    // Парсим GET запрос
    let (base_filename, requested_width, extension) = parse_file_path(&normalized_path);
    let ext = extension.as_str().to_lowercase();
    let filekey = format!("{}.{}", base_filename, &ext);

    info!(
        "Parsed request - base: {}, width: {}, ext: {}",
        base_filename, requested_width, ext
    );

    // Caching handled by Vercel Edge - focus on fast file serving
    let content_type = match get_mime_type(&ext) {
        Some(mime) => mime.to_string(),
        None => match find_file_by_pattern(None, &base_filename).await {
            Ok(Some(found_file)) => {
                if let Some(found_ext) = found_file.split('.').next_back() {
                    get_mime_type(found_ext)
                        .unwrap_or("application/octet-stream")
                        .to_string()
                } else {
                    "application/octet-stream".to_string()
                }
            }
            _ => {
                error!("Unsupported file format for: {}", base_filename);
                return Err(ErrorInternalServerError("Unsupported file format"));
            }
        },
    };

    info!("Content-Type: {}", content_type);

    return match state.get_path(&filekey).await {
        Ok(Some(stored_path)) => {
            warn!("Found stored path in DB: {}", stored_path);
            warn!(
                "Checking Storj path - bucket: {}, path: {}",
                state.bucket, stored_path
            );
            if check_file_exists(&state.storj_client, &state.bucket, &stored_path).await? {
                warn!("File exists in Storj: {}", stored_path);
                // Просто отдаем файл, миниатюры генерирует Vercel Edge API
                serve_file(&stored_path, &state, &req).await
            } else {
                warn!(
                    "Attempting to load from AWS - bucket: {}, path: {}",
                    state.bucket, stored_path
                );

                // Определяем тип медиа из content_type
                let media_type = content_type.split("/").next().unwrap_or("image");

                // Создаем варианты путей с обоими регистрами расширения
                let paths_lower = vec![
                    stored_path.clone(),
                    // format!("production/{}", stored_path),
                    format!("production/{}/{}", media_type, stored_path),
                ];

                // Создаем те же пути, но с оригинальным регистром расширения
                let orig_ext = extension.as_str(); // оригинальное расширение
                let orig_stored_path = format!("{}.{}", base_filename, orig_ext);
                let paths_orig = vec![
                    orig_stored_path.clone(),
                    // format!("production/{}", orig_stored_path),
                    format!("production/{}/{}", media_type, orig_stored_path),
                ];

                // Объединяем все пути для проверки
                let all_paths = paths_lower.into_iter().chain(paths_orig.into_iter());

                for path in all_paths {
                    warn!("Trying AWS path: {}", path);
                    match load_file_from_s3(&state.aws_client, &state.bucket, &path).await {
                        Ok(filedata) => {
                            warn!(
                                "Successfully loaded file from AWS, size: {} bytes",
                                filedata.len()
                            );
                            warn!("Attempting to upload to Storj with key: {}", filekey);

                            if let Err(e) = upload_to_s3(
                                &state.storj_client,
                                &state.bucket,
                                &filekey,
                                filedata.clone(),
                                &content_type,
                            )
                            .await
                            {
                                error!("Failed to upload to Storj: {} - Error: {}", filekey, e);
                            } else {
                                warn!("Successfully uploaded to Storj: {}", filekey);
                            }

                            let elapsed = start_time.elapsed();
                            info!("File served from AWS in {:?}: {}", elapsed, path);

                            // Используем Vercel-совместимый ответ для Vercel запросов
                            if is_vercel_request(&req) {
                                let etag = format!("\"{:x}\"", md5::compute(&filedata));
                                return Ok(create_vercel_compatible_response(
                                    &content_type,
                                    filedata,
                                    &etag,
                                ));
                            } else {
                                return Ok(create_file_response_with_analytics(
                                    &content_type,
                                    filedata,
                                    &req,
                                    &path,
                                ));
                            }
                        }
                        Err(err) => {
                            warn!("Failed to load from AWS path {}: {:?}", path, err);
                            continue;
                        }
                    }
                }

                error!("Failed to load from any AWS path for: {}", stored_path);
                Err(ErrorInternalServerError("Failed to load file from AWS"))
            }
        }
        Ok(None) => {
            warn!("No stored path found in DB for: {}", filekey);
            let ct_parts = content_type.split("/").collect::<Vec<&str>>();

            // Создаем два варианта пути - с оригинальным расширением и с нижним регистром
            let filepath_lower = format!("production/{}/{}.{}", ct_parts[0], base_filename, ext);
            let filepath_orig =
                format!("production/{}/{}.{}", ct_parts[0], base_filename, extension);

            warn!(
                "Looking up files with paths: {} or {} in bucket: {}",
                filepath_lower, filepath_orig, state.bucket
            );

            // Проверяем существование файла с обоими вариантами расширения
            let exists_in_aws_lower =
                check_file_exists(&state.aws_client, &state.bucket, &filepath_lower).await?;
            let exists_in_aws_orig =
                check_file_exists(&state.aws_client, &state.bucket, &filepath_orig).await?;

            let filepath = if exists_in_aws_orig {
                filepath_orig
            } else if exists_in_aws_lower {
                filepath_lower
            } else {
                // Если файл не найден ни с одним из расширений, используем нижний регистр по умолчанию
                filepath_lower
            };

            let exists_in_storj =
                check_file_exists(&state.storj_client, &state.bucket, &filepath).await?;
            warn!("Checking existence in Storj: {}", exists_in_storj);

            if exists_in_storj {
                warn!("file {} exists in storj, serving directly", filepath);
                // Файл существует в Storj, отдаем его напрямую
                return serve_file(&filepath, &state, &req).await;
            } else {
                warn!("file {} does not exist in storj", filepath);
            }

            let exists_in_aws =
                check_file_exists(&state.aws_client, &state.bucket, &filepath).await?;
            warn!("Checking existence in AWS: {}", exists_in_aws);

            if exists_in_aws {
                warn!("File found in AWS, attempting to download: {}", filepath);
                match load_file_from_s3(&state.aws_client, &state.bucket, &filepath).await {
                    Ok(filedata) => {
                        warn!(
                            "Successfully downloaded file from AWS, size: {} bytes",
                            filedata.len()
                        );
                        if let Err(e) = upload_to_s3(
                            &state.storj_client,
                            &state.bucket,
                            &filekey,
                            filedata.clone(),
                            &content_type,
                        )
                        .await
                        {
                            warn!("cannot upload to storj: {}", e);
                        } else {
                            warn!("file {} uploaded to storj", filekey);
                            state.set_path(&filekey, &filepath).await;
                        }
                        let elapsed = start_time.elapsed();
                        info!("File served from AWS in {:?}: {}", elapsed, filepath);

                        // Используем Vercel-совместимый ответ для Vercel запросов
                        if is_vercel_request(&req) {
                            let etag = format!("\"{:x}\"", md5::compute(&filedata));
                            Ok(create_vercel_compatible_response(
                                &content_type,
                                filedata,
                                &etag,
                            ))
                        } else {
                            Ok(create_file_response_with_analytics(
                                &content_type,
                                filedata,
                                &req,
                                &filepath,
                            ))
                        }
                    }
                    Err(e) => {
                        error!("Failed to download from AWS: {} - Error: {}", filepath, e);
                        Err(ErrorInternalServerError(e))
                    }
                }
            } else {
                error!("File not found in either Storj or AWS: {}", filepath);
                Err(ErrorNotFound("file does not exist"))
            }
        }
        Err(e) => {
            let elapsed = start_time.elapsed();
            error!(
                "Database error while getting path: {} in {:?} - Full error: {:?}",
                filekey, elapsed, e
            );
            Err(ErrorInternalServerError(e))
        }
    };
}