use argon2::{
    Algorithm, Argon2, Params, PasswordHasher, Version,
    password_hash::{SaltString, rand_core::OsRng},
};
use fake::{Fake, faker::internet::en::SafeEmail};
use linkify::{Link, LinkFinder};
use once_cell::sync::Lazy;
use sqlx::{Connection, Executor, PgConnection, PgPool};
use uuid::Uuid;
use wiremock::{
    Mock, MockBuilder, MockServer, ResponseTemplate,
    matchers::{method, path},
};
use zero2prod::{
    configuration::{DatabaseSettings, get_configuration},
    email_client::EmailClient,
    issue_delivery_worker::{ExecutionOutcome, try_execute_task},
    startup::Application,
    telemetry::init_subscriber,
};

static TRACING: Lazy<()> = Lazy::new(|| {
    if std::env::var("TEST_LOG").is_ok() {
        init_subscriber(std::io::stdout);
    } else {
        init_subscriber(std::io::sink);
    }
});

pub struct ConfirmationLinks {
    pub html: reqwest::Url,
    pub text: reqwest::Url,
}

pub struct TestUser {
    pub user_id: Uuid,
    pub username: String,
    pub password: String,
}

impl TestUser {
    pub fn generate() -> Self {
        Self {
            user_id: Uuid::new_v4(),
            username: Uuid::new_v4().to_string(),
            password: Uuid::new_v4().to_string(),
        }
    }

    pub async fn store(&self, connection_pool: &PgPool) {
        let salt = SaltString::generate(&mut OsRng);
        let password_hash = Argon2::new(
            Algorithm::Argon2id,
            Version::V0x13,
            Params::new(1500, 2, 1, None).unwrap(),
        )
        .hash_password(self.password.as_bytes(), &salt)
        .unwrap()
        .to_string();
        sqlx::query!(
            "INSERT INTO users (user_id, username, password_hash) VALUES ($1, $2, $3)",
            self.user_id,
            self.username,
            password_hash
        )
        .execute(connection_pool)
        .await
        .expect("Failed to create test user");
    }
}

pub struct TestApp {
    pub address: String,
    pub connection_pool: PgPool,
    pub email_server: wiremock::MockServer,
    pub port: u16,
    pub test_user: TestUser,
    pub api_client: reqwest::Client,
    pub email_client: EmailClient,
}

impl TestApp {
    pub async fn spawn() -> Self {
        Lazy::force(&TRACING);

        let email_server = MockServer::start().await;
        let configuration = {
            let mut c = get_configuration().expect("Failed to read configuration");
            c.database.database_name = Uuid::new_v4().to_string();
            c.application.port = 0;
            c.email_client.base_url = email_server.uri();
            c
        };
        let local_addr = configuration.application.host.clone();
        let connection_pool = configure_database(&configuration.database).await;
        let email_client = EmailClient::build(configuration.email_client.clone()).unwrap();
        let application = Application::build(configuration)
            .await
            .expect("Failed to build application");
        let port = application.port();
        let address = format!("http://{}:{}", local_addr, port);
        let test_user = TestUser::generate();
        test_user.store(&connection_pool).await;
        let api_client = reqwest::Client::builder()
            .redirect(reqwest::redirect::Policy::none())
            .cookie_store(true)
            .build()
            .unwrap();
        let app = TestApp {
            address,
            connection_pool,
            email_server,
            port,
            test_user,
            api_client,
            email_client,
        };

        tokio::spawn(application.run_until_stopped());

        app
    }

    pub async fn create_unconfirmed_subscriber(&self) -> ConfirmationLinks {
        let email: String = SafeEmail().fake();
        let body = format!("email={email}");

        let _mock_guard = when_sending_an_email()
            .respond_with(ResponseTemplate::new(200))
            .named("Create unconfirmed subscriber")
            .expect(1)
            .mount_as_scoped(&self.email_server)
            .await;

        self.post_subscriptions(body)
            .await
            .error_for_status()
            .unwrap();

        let email_request = &self
            .email_server
            .received_requests()
            .await
            .unwrap()
            .pop()
            .unwrap();

        self.get_confirmation_links(email_request)
    }

    pub async fn create_confirmed_subscriber(&self) {
        let confirmation_links = self.create_unconfirmed_subscriber().await;
        reqwest::get(confirmation_links.html)
            .await
            .unwrap()
            .error_for_status()
            .unwrap();
    }

    pub async fn dispatch_all_pending_emails(&self) {
        loop {
            if let ExecutionOutcome::EmptyQueue =
                try_execute_task(&self.connection_pool, &self.email_client)
                    .await
                    .unwrap()
            {
                break;
            }
        }
    }

    pub fn get_unsubscribe_links(&self, request: &wiremock::Request) -> ConfirmationLinks {
        let body: serde_json::Value = serde_json::from_slice(&request.body).unwrap();
        let get_link = |s: &str| {
            let links = get_links(s);
            assert!(!links.is_empty());
            let mut confirmation_link =
                reqwest::Url::parse(links.last().unwrap().as_str()).unwrap();
            assert_eq!(confirmation_link.host_str().unwrap(), "127.0.0.1");
            confirmation_link.set_port(Some(self.port)).unwrap();
            confirmation_link
        };

        let html = get_link(body["html"].as_str().unwrap());
        let text = get_link(body["text"].as_str().unwrap());
        ConfirmationLinks { html, text }
    }

    pub fn get_confirmation_links(&self, request: &wiremock::Request) -> ConfirmationLinks {
        let body: serde_json::Value = serde_json::from_slice(&request.body).unwrap();
        let get_link = |s: &str| {
            let links = get_links(s);
            assert_eq!(links.len(), 1);
            let mut confirmation_link = reqwest::Url::parse(links[0].as_str()).unwrap();
            assert_eq!(confirmation_link.host_str().unwrap(), "127.0.0.1");
            confirmation_link.set_port(Some(self.port)).unwrap();
            confirmation_link
        };

        let html = get_link(body["html"].as_str().unwrap());
        let text = get_link(body["text"].as_str().unwrap());
        ConfirmationLinks { html, text }
    }

    pub async fn get_unsubscribe_confirm(&self, unsubscribe_token: &str) -> reqwest::Response {
        self.api_client
            .get(format!(
                "{}/unsubscribe/confirm?token={}",
                &self.address, unsubscribe_token
            ))
            .send()
            .await
            .expect("Failed to execute request")
    }

    pub async fn get_admin_dashboard(&self) -> reqwest::Response {
        self.api_client
            .get(format!("{}/admin/dashboard", &self.address))
            .send()
            .await
            .expect("Failed to execute request")
    }

    pub async fn get_admin_dashboard_html(&self) -> String {
        self.get_admin_dashboard().await.text().await.unwrap()
    }

    pub async fn post_subscriptions(&self, body: String) -> reqwest::Response {
        self.api_client
            .post(format!("{}/subscriptions", self.address))
            .header("Content-Type", "application/x-www-form-urlencoded")
            .body(body)
            .send()
            .await
            .expect("Failed to execute request")
    }

    pub async fn post_newsletters<Body>(&self, body: &Body) -> reqwest::Response
    where
        Body: serde::Serialize,
    {
        self.api_client
            .post(format!("{}/admin/newsletters", self.address))
            .form(body)
            .send()
            .await
            .expect("Failed to execute request")
    }

    pub async fn post_login<Body>(&self, body: &Body) -> reqwest::Response
    where
        Body: serde::Serialize,
    {
        self.api_client
            .post(format!("{}/login", self.address))
            .form(body)
            .send()
            .await
            .expect("Failed to execute request")
    }

    pub async fn admin_login(&self) {
        let login_body = serde_json::json!({
            "username": self.test_user.username,
            "password": self.test_user.password
        });
        self.post_login(&login_body).await;
    }

    pub async fn post_logout(&self) -> reqwest::Response {
        self.api_client
            .post(format!("{}/admin/logout", self.address))
            .send()
            .await
            .expect("Failed to execute request")
    }

    pub async fn post_change_password<Body>(&self, body: &Body) -> reqwest::Response
    where
        Body: serde::Serialize,
    {
        self.api_client
            .post(format!("{}/admin/password", self.address))
            .form(body)
            .send()
            .await
            .expect("Failed to execute request")
    }

    pub async fn post_create_post<Body>(&self, body: &Body) -> reqwest::Response
    where
        Body: serde::Serialize,
    {
        self.api_client
            .post(format!("{}/admin/posts", self.address))
            .form(body)
            .send()
            .await
            .expect("Failed to execute request")
    }

    pub async fn post_unsubscribe<Body>(&self, body: &Body) -> reqwest::Response
    where
        Body: serde::Serialize,
    {
        self.api_client
            .post(format!("{}/unsubscribe", self.address))
            .form(body)
            .send()
            .await
            .expect("Failed to execute request")
    }
}

async fn configure_database(config: &DatabaseSettings) -> PgPool {
    let mut connection = PgConnection::connect_with(&config.without_db())
        .await
        .expect("Failed to connect to Postgres");
    connection
        .execute(format!(r#"CREATE DATABASE "{}";"#, config.database_name).as_ref())
        .await
        .expect("Failed to create the database");

    let connection_pool = PgPool::connect_with(config.with_db())
        .await
        .expect("Failed to connect to Postgres");
    sqlx::migrate!("./migrations")
        .run(&connection_pool)
        .await
        .expect("Failed to migrate the database");

    connection_pool
}

pub fn assert_is_redirect_to(response: &reqwest::Response, location: &str) {
    assert!(
        response.status().as_u16() == 303
            || response.status().as_u16() == 200
                && response.headers().get("hx-redirect").unwrap() == location
    );
}

pub fn when_sending_an_email() -> MockBuilder {
    Mock::given(path("/email")).and(method("POST"))
}

pub fn fake_newsletter_body() -> serde_json::Value {
    serde_json::json!({
        "title": "Newsletter title",
        "text": "Newsletter body as plain text",
        "html": "<p>Newsletter body as HTML</p>",
        "idempotency_key": Uuid::new_v4().to_string(),

    })
}

pub fn fake_post_body() -> serde_json::Value {
    serde_json::json!({
        "title": "Post title",
        "content": "Post content",
        "idempotency_key": Uuid::new_v4().to_string(),

    })
}

pub fn get_links(s: &'_ str) -> Vec<Link<'_>> {
    LinkFinder::new()
        .links(s)
        .filter(|l| *l.kind() == linkify::LinkKind::Url)
        .collect()
}