//! Conversion of Locust load test used for the Drupal memcache module, from
//! https://github.com/tag1consulting/drupal-loadtest/
//!
//! To run, you must set up the load test environment as described in the above
//! repository, and then run the example. You'll need to set --host and may want
//! to set other command line options as well, starting with:
//!      cargo run --release --example drupal_loadtest --
//!
//! ## License
//!
//! Copyright 2020 Jeremy Andrews
//!
//! Licensed 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 swanling::prelude::*;

use rand::Rng;
use regex::Regex;

fn main() -> Result<(), SwanlingError> {
    SwanlingAttack::initialize()?
        .register_taskset(
            taskset!("AnonBrowsingUser")
                .set_weight(4)?
                .register_task(
                    task!(drupal_loadtest_front_page)
                        .set_weight(15)?
                        .set_name("(Anon) front page"),
                )
                .register_task(
                    task!(drupal_loadtest_node_page)
                        .set_weight(10)?
                        .set_name("(Anon) node page"),
                )
                .register_task(
                    task!(drupal_loadtest_profile_page)
                        .set_weight(3)?
                        .set_name("(Anon) user page"),
                ),
        )
        .register_taskset(
            taskset!("AuthBrowsingUser")
                .set_weight(1)?
                .register_task(
                    task!(drupal_loadtest_login)
                        .set_on_start()
                        .set_name("(Auth) login"),
                )
                .register_task(
                    task!(drupal_loadtest_front_page)
                        .set_weight(15)?
                        .set_name("(Auth) front page"),
                )
                .register_task(
                    task!(drupal_loadtest_node_page)
                        .set_weight(10)?
                        .set_name("(Auth) node page"),
                )
                .register_task(
                    task!(drupal_loadtest_profile_page)
                        .set_weight(3)?
                        .set_name("(Auth) user page"),
                )
                .register_task(
                    task!(drupal_loadtest_post_comment)
                        .set_weight(3)?
                        .set_name("(Auth) comment form"),
                ),
        )
        .execute()?
        .print();

    Ok(())
}

/// View the front page.
async fn drupal_loadtest_front_page(user: &SwanlingUser) -> SwanlingTaskResult {
    let mut swanling = user.get("/").await?;

    match swanling.response {
        Ok(response) => {
            // Copy the headers so we have them for logging if there are errors.
            let headers = &response.headers().clone();
            match response.text().await {
                Ok(t) => {
                    let re = Regex::new(r#"src="(.*?)""#).unwrap();
                    // Collect copy of URLs to run them async
                    let mut urls = Vec::new();
                    for url in re.captures_iter(&t) {
                        if url[1].contains("/misc") || url[1].contains("/themes") {
                            urls.push(url[1].to_string());
                        }
                    }
                    for asset in &urls {
                        let _ = user.get_named(asset, "static asset").await;
                    }
                }
                Err(e) => {
                    // This will automatically get written to the error log if enabled, and will
                    // be displayed to stdout if `-v` is enabled when running the load test.
                    return user.set_failure(
                        &format!("front_page: failed to parse page: {}", e),
                        &mut swanling.request,
                        Some(&headers),
                        None,
                    );
                }
            }
        }
        Err(e) => {
            // This will automatically get written to the error log if enabled, and will
            // be displayed to stdout if `-v` is enabled when running the load test.
            return user.set_failure(
                &format!("front_page: no response from server: {}", e),
                &mut swanling.request,
                None,
                None,
            );
        }
    }

    Ok(())
}

/// View a node from 1 to 10,000, created by preptest.sh.
async fn drupal_loadtest_node_page(user: &SwanlingUser) -> SwanlingTaskResult {
    let nid = rand::thread_rng().gen_range(1..10_000);
    let _swanling = user.get(format!("/node/{}", &nid).as_str()).await?;

    Ok(())
}

/// View a profile from 2 to 5,001, created by preptest.sh.
async fn drupal_loadtest_profile_page(user: &SwanlingUser) -> SwanlingTaskResult {
    let uid = rand::thread_rng().gen_range(2..5_001);
    let _swanling = user.get(format!("/user/{}", &uid).as_str()).await?;

    Ok(())
}

/// Log in.
async fn drupal_loadtest_login(user: &SwanlingUser) -> SwanlingTaskResult {
    let mut swanling = user.get("/user").await?;

    match swanling.response {
        Ok(response) => {
            // Copy the headers so we have them for logging if there are errors.
            let headers = &response.headers().clone();
            match response.text().await {
                Ok(html) => {
                    let re = Regex::new(r#"name="form_build_id" value=['"](.*?)['"]"#).unwrap();
                    let form_build_id = match re.captures(&html) {
                        Some(f) => f,
                        None => {
                            // This will automatically get written to the error log if enabled, and will
                            // be displayed to stdout if `-v` is enabled when running the load test.
                            return user.set_failure(
                                "login: no form_build_id on page: /user page",
                                &mut swanling.request,
                                Some(&headers),
                                Some(&html),
                            );
                        }
                    };

                    // Log the user in.
                    let uid: usize = rand::thread_rng().gen_range(3..5_002);
                    let username = format!("user{}", uid);
                    let params = [
                        ("name", username.as_str()),
                        ("pass", "12345"),
                        ("form_build_id", &form_build_id[1]),
                        ("form_id", "user_login"),
                        ("op", "Log+in"),
                    ];
                    let request_builder = user.swanling_post("/user").await?;
                    let _swanling = user
                        .swanling_send(request_builder.form(&params), None)
                        .await;
                    // @TODO: verify that we actually logged in.
                }
                Err(e) => {
                    // This will automatically get written to the error log if enabled, and will
                    // be displayed to stdout if `-v` is enabled when running the load test.
                    return user.set_failure(
                        &format!("login: unexpected error when loading /user page: {}", e),
                        &mut swanling.request,
                        Some(&headers),
                        None,
                    );
                }
            }
        }
        // Swanling will catch this error.
        Err(e) => {
            // This will automatically get written to the error log if enabled, and will
            // be displayed to stdout if `-v` is enabled when running the load test.
            return user.set_failure(
                &format!("login: no response from server: {}", e),
                &mut swanling.request,
                None,
                None,
            );
        }
    }

    Ok(())
}

/// Post a comment.
async fn drupal_loadtest_post_comment(user: &SwanlingUser) -> SwanlingTaskResult {
    let nid: i32 = rand::thread_rng().gen_range(1..10_000);
    let node_path = format!("node/{}", &nid);
    let comment_path = format!("/comment/reply/{}", &nid);

    let mut swanling = user.get(&node_path).await?;

    match swanling.response {
        Ok(response) => {
            // Copy the headers so we have them for logging if there are errors.
            let headers = &response.headers().clone();
            match response.text().await {
                Ok(html) => {
                    // Extract the form_build_id from the user login form.
                    let re = Regex::new(r#"name="form_build_id" value=['"](.*?)['"]"#).unwrap();
                    let form_build_id = match re.captures(&html) {
                        Some(f) => f,
                        None => {
                            // This will automatically get written to the error log if enabled, and will
                            // be displayed to stdout if `-v` is enabled when running the load test.
                            return user.set_failure(
                                &format!("post_comment: no form_build_id found on {}", &node_path),
                                &mut swanling.request,
                                Some(&headers),
                                Some(&html),
                            );
                        }
                    };

                    let re = Regex::new(r#"name="form_token" value=['"](.*?)['"]"#).unwrap();
                    let form_token = match re.captures(&html) {
                        Some(f) => f,
                        None => {
                            // This will automatically get written to the error log if enabled, and will
                            // be displayed to stdout if `-v` is enabled when running the load test.
                            return user.set_failure(
                                &format!("post_comment: no form_token found on {}", &node_path),
                                &mut swanling.request,
                                Some(&headers),
                                Some(&html),
                            );
                        }
                    };

                    let re = Regex::new(r#"name="form_id" value=['"](.*?)['"]"#).unwrap();
                    let form_id = match re.captures(&html) {
                        Some(f) => f,
                        None => {
                            // This will automatically get written to the error log if enabled, and will
                            // be displayed to stdout if `-v` is enabled when running the load test.
                            return user.set_failure(
                                &format!("post_comment: no form_id found on {}", &node_path),
                                &mut swanling.request,
                                Some(&headers),
                                Some(&html),
                            );
                        }
                    };
                    // Optionally uncomment to log form_id, form_build_id, and form_token, together with
                    // the full body of the page. This is useful when modifying the load test.
                    /*
                    user.log_debug(
                        &format!(
                            "form_id: {}, form_build_id: {}, form_token: {}",
                            &form_id[1], &form_build_id[1], &form_token[1]
                        ),
                        Some(&swanling.request),
                        Some(&headers),
                        Some(&html),
                    );
                    */

                    let comment_body = "this is a test comment body";
                    let params = [
                        ("subject", "this is a test comment subject"),
                        ("comment_body[und][0][value]", &comment_body),
                        ("comment_body[und][0][format]", "filtered_html"),
                        ("form_build_id", &form_build_id[1]),
                        ("form_token", &form_token[1]),
                        ("form_id", &form_id[1]),
                        ("op", "Save"),
                    ];

                    // Post the comment.
                    let request_builder = user.swanling_post(&comment_path).await?;
                    let mut swanling = user
                        .swanling_send(request_builder.form(&params), None)
                        .await?;

                    // Verify that the comment posted.
                    match swanling.response {
                        Ok(response) => {
                            // Copy the headers so we have them for logging if there are errors.
                            let headers = &response.headers().clone();
                            match response.text().await {
                                Ok(html) => {
                                    if !html.contains(&comment_body) {
                                        // This will automatically get written to the error log if enabled, and will
                                        // be displayed to stdout if `-v` is enabled when running the load test.
                                        return user.set_failure(
                                            &format!("post_comment: no comment showed up after posting to {}", &comment_path),
                                            &mut swanling.request,
                                            Some(&headers),
                                            Some(&html),
                                        );
                                    }
                                }
                                Err(e) => {
                                    // This will automatically get written to the error log if enabled, and will
                                    // be displayed to stdout if `-v` is enabled when running the load test.
                                    return user.set_failure(
                                        &format!(
                                            "post_comment: unexpected error when posting to {}: {}",
                                            &comment_path, e
                                        ),
                                        &mut swanling.request,
                                        Some(&headers),
                                        None,
                                    );
                                }
                            }
                        }
                        Err(e) => {
                            // This will automatically get written to the error log if enabled, and will
                            // be displayed to stdout if `-v` is enabled when running the load test.
                            return user.set_failure(
                                &format!(
                                    "post_comment: no response when posting to {}: {}",
                                    &comment_path, e
                                ),
                                &mut swanling.request,
                                None,
                                None,
                            );
                        }
                    }
                }
                Err(e) => {
                    // This will automatically get written to the error log if enabled, and will
                    // be displayed to stdout if `-v` is enabled when running the load test.
                    return user.set_failure(
                        &format!("post_comment: no text when loading {}: {}", &node_path, e),
                        &mut swanling.request,
                        None,
                        None,
                    );
                }
            }
        }
        Err(e) => {
            // This will automatically get written to the error log if enabled, and will
            // be displayed to stdout if `-v` is enabled when running the load test.
            return user.set_failure(
                &format!(
                    "post_comment: no response when loading {}: {}",
                    &node_path, e
                ),
                &mut swanling.request,
                None,
                None,
            );
        }
    }

    Ok(())
}