use std::str::FromStr;

use axum::{
    extract::{Path, State},
    response::IntoResponse,
    Json,
};
use axum_extra::{headers::Authorization, routing::Resource, TypedHeader};
use serde::{Deserialize, Serialize};
use sqlx::FromRow;
use time::OffsetDateTime;
use uuid::Uuid;

use crate::{auth::AccessClaims, state::AppState};

use super::error::Error;

pub fn router() -> Resource<AppState> {
    Resource::named("users").create(create).show(show)
}

#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize, FromRow)]
#[serde(rename_all = "camelCase")]
pub struct UserSchema {
    pub uuid: Uuid,
    pub name: String,
    pub email: String,
    pub session_epoch: OffsetDateTime,
    pub created_at: OffsetDateTime,
    pub updated_at: OffsetDateTime,
}

impl Default for UserSchema {
    fn default() -> Self {
        let now = time::OffsetDateTime::now_utc();
        Self {
            uuid: Default::default(),
            name: Default::default(),
            email: Default::default(),
            session_epoch: now,
            created_at: now,
            updated_at: now,
        }
    }
}

#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
pub struct RegisterSchema {
    pub name: String,
    pub email: String,
    pub password: String,
}

pub async fn create(
    State(state): State<AppState>,
    Json(RegisterSchema {
        name,
        email,
        password,
    }): Json<RegisterSchema>,
) -> impl IntoResponse {
    email_address::EmailAddress::from_str(&email)?;

    let exists: Option<bool> =
        sqlx::query_scalar("SELECT EXISTS(SELECT 1 FROM users WHERE email = $1 LIMIT 1)")
            .bind(email.to_ascii_lowercase())
            .fetch_one(&state.pool)
            .await?;

    if exists.is_some_and(|b| b) {
        return Err(Error::EmailExists);
    }

    let mut transaction = state.pool.begin().await?;

    let user = sqlx::query_as!(
        UserSchema,
        "INSERT INTO users (name,email) VALUES ($1, $2) RETURNING *",
        name,
        email.to_ascii_lowercase(),
    )
    .fetch_one(&mut *transaction)
    .await?;

    let (parts, _) = crate::auth::create(
        State(state),
        TypedHeader(Authorization::basic(&user.uuid.to_string(), &password)),
    )
    .await?
    .into_response()
    .into_parts();

    transaction.commit().await?;
    Ok((parts, Json(user)))
}

pub async fn show(
    Path(uuid): Path<Uuid>,
    State(state): State<AppState>,
    AccessClaims { sub, .. }: AccessClaims,
) -> Result<impl IntoResponse, Error> {
    if uuid != sub {
        return Err(Error::InvalidToken);
    }

    sqlx::query_as!(
        UserSchema,
        "SELECT * FROM users WHERE uuid = $1 LIMIT 1",
        sub
    )
    .fetch_optional(&state.pool)
    .await?
    .ok_or_else(|| Error::UserNotFound)
    .map(Json)
}

#[cfg(test)]
mod tests {
    use super::*;

    use axum::{
        body::Body,
        http::{
            header::{CONTENT_TYPE, COOKIE},
            HeaderValue, Request, StatusCode,
        },
        Router,
    };

    use http_body_util::BodyExt;
    use sqlx::PgPool;
    use tower::ServiceExt;

    use crate::{
        auth::AccessClaims,
        tests::{setup_test_env, TestResult},
    };

    const UUID: uuid::Uuid = uuid::uuid!("4c14f795-86f0-4361-a02f-0edb966fb145");

    #[sqlx::test(fixtures(path = "../../fixtures", scripts("users")))]
    async fn test_uuid_ok(pool: PgPool) -> TestResult {
        setup_test_env();

        let router = Router::new().merge(router()).with_state(AppState { pool });

        let user = UserSchema {
            uuid: UUID,
            name: "Arthur Dent".to_string(),
            email: "adent@earth.sol".to_string(),
            ..Default::default()
        };

        let request = Request::builder()
            .uri(format!("/users/{UUID}"))
            .header(COOKIE, HeaderValue::try_from(AccessClaims::new(UUID))?)
            .body(Body::empty())?;

        let response = router.oneshot(request).await?;

        assert_eq!(StatusCode::OK, response.status());

        let body_bytes = response.into_body().collect().await?.to_bytes();
        let UserSchema {
            uuid, name, email, ..
        } = serde_json::from_slice(&body_bytes)?;

        assert_eq!(user.uuid, uuid);
        assert_eq!(user.name, name);
        assert_eq!(user.email, email);

        Ok(())
    }

    #[sqlx::test]
    async fn test_uuid_not_found(pool: PgPool) -> TestResult {
        setup_test_env();

        let router = Router::new().merge(router()).with_state(AppState { pool });

        let request = Request::builder()
            .uri(format!("/users/{UUID}"))
            .header(COOKIE, HeaderValue::try_from(AccessClaims::new(UUID))?)
            .body(Body::empty())?;

        let response = router.oneshot(request).await?;

        assert_eq!(StatusCode::NOT_FOUND, response.status());

        Ok(())
    }

    #[sqlx::test]
    async fn test_unauthorized_invalid_token_signature(pool: PgPool) -> TestResult {
        setup_test_env();

        let router = Router::new().merge(router()).with_state(AppState { pool });

        let request = Request::builder()
            .uri(format!("/users/{UUID}"))
            .header(
                COOKIE,
                HeaderValue::try_from(AccessClaims::new(uuid::Uuid::new_v4()))?,
            )
            .body(Body::empty())?;

        let response = router.oneshot(request).await?;

        assert_eq!(StatusCode::UNAUTHORIZED, response.status());

        Ok(())
    }

    #[sqlx::test]
    async fn test_unauthorized_invalid_token_format(pool: PgPool) -> TestResult {
        setup_test_env();

        let router = Router::new().merge(router()).with_state(AppState { pool });

        let request = Request::builder()
            .uri(format!("/users/{UUID}"))
            .header(COOKIE, "token=sadfasdfsdfs")
            .body(Body::empty())?;

        let response = router.oneshot(request).await?;

        assert_eq!(StatusCode::UNPROCESSABLE_ENTITY, response.status());

        Ok(())
    }

    #[sqlx::test]
    async fn test_unauthorized_missing_token(pool: PgPool) -> TestResult {
        setup_test_env();

        let router = Router::new().merge(router()).with_state(AppState { pool });

        let request = Request::builder()
            .uri(format!("/users/{UUID}"))
            .body(Body::empty())?;

        let response = router.oneshot(request).await?;

        assert_eq!(StatusCode::UNAUTHORIZED, response.status());

        Ok(())
    }

    #[sqlx::test]
    async fn test_create_created(pool: PgPool) -> TestResult {
        setup_test_env();

        let router = Router::new().merge(router()).with_state(AppState { pool });

        let user = RegisterSchema {
            name: "Arthur Dent".to_string(),
            email: "adent@earth.sol".to_string(),
            password: "solongandthanksforallthefish".to_string(),
        };

        let request = Request::builder()
            .uri("/users")
            .method("POST")
            .header(CONTENT_TYPE, mime::APPLICATION_JSON.as_ref())
            .body(Body::from(serde_json::to_vec(&user)?))?;

        let response = router.oneshot(request).await?;

        assert_eq!(StatusCode::CREATED, response.status());

        let body_bytes = response.into_body().collect().await?.to_bytes();
        let UserSchema { name, email, .. } = serde_json::from_slice(&body_bytes)?;

        assert_eq!(user.name, name);
        assert_eq!(user.email, email);

        Ok(())
    }

    #[sqlx::test(fixtures(path = "../../fixtures", scripts("users")))]
    async fn test_create_conflict(pool: PgPool) -> TestResult {
        setup_test_env();

        let router = Router::new().merge(router()).with_state(AppState { pool });

        let user = RegisterSchema {
            name: "Arthur Dent".to_string(),
            email: "adent@earth.sol".to_string(),
            password: "solongandthanksforallthefish".to_string(),
        };

        let request = Request::builder()
            .uri("/users")
            .method("POST")
            .header(CONTENT_TYPE, mime::APPLICATION_JSON.as_ref())
            .body(Body::from(serde_json::to_vec(&user)?))?;

        let response = router.oneshot(request).await?;

        assert_eq!(StatusCode::CONFLICT, response.status());

        Ok(())
    }
}