use actix_web::http::StatusCode;
use actix_web::HttpResponse;
use include_dir::Dir;
use tera::Tera;

fn tera_includedir_walk_folder_inner(collected: &mut Vec<(String, String)>, tera: &mut Tera, dir: &Dir) {
    for f in dir.files() {
        let halves: Vec<_> = f.path().file_name().unwrap().to_str().unwrap().split('.').collect();

        if halves.last().unwrap() != &"tera" {
            debug!("Bad file: {:?}", f);
            continue;
        }

        let name = halves.first().unwrap();
        let content = f.contents_utf8().unwrap();

        let p = f.path().parent().unwrap().join(name);
        let template_path = p.to_str().unwrap();

        debug!("Add template: {}", template_path);
        collected.push((template_path.to_string(), content.to_string()));
    }

    for subdir in dir.dirs() {
        tera_includedir_walk_folder_inner(collected, tera, subdir)
    }
}

pub(crate) trait TeraExt {
    fn add_include_dir_templates(&mut self, dir: &Dir) -> tera::Result<()>;

    fn build_response(&self, template: &str, context: &tera::Context) -> actix_web::Result<HttpResponse> {
        self.build_err_response(StatusCode::OK, template, context)
    }

    fn build_err_response(&self, code: StatusCode, template: &str, context: &tera::Context) -> actix_web::Result<HttpResponse>;
}

impl TeraExt for Tera {
    fn add_include_dir_templates(&mut self, dir: &Dir) -> tera::Result<()> {
        debug!("Walk dir: {:?}", dir.path());
        let mut templates = vec![];
        tera_includedir_walk_folder_inner(&mut templates, self, dir);
        self.add_raw_templates(templates)
    }

    fn build_err_response(&self, code: StatusCode, template: &str, context: &tera::Context) -> actix_web::Result<HttpResponse> {
        let html = self.render(template, context).map_err(|e| {
            actix_web::error::ErrorInternalServerError(e)
        })?;

        Ok(HttpResponse::build(code).body(html))
    }
}