//! A fake Jellyfin server the online repository can actually talk to.
//!
//! # Why this exists
//!
//! Before it, `src-tauri/` contained no HTTP mocking of any kind. Every test of
//! the ~4,800-line online adapter asserted on a *constructed URL string*, and
//! not one exercised a response. That has a specific, recorded cost: a deleted
//! test file re-implemented the URL builders inside its own mock and then
//! asserted against itself, and `online.rs` still carries the comment recording
//! that the production builder meanwhile shipped a `/Videos/{id}/download`
//! endpoint which 404s on real servers — silently breaking every download while
//! the "test" stayed green.
//!
//! So the rule here is: **assert against a response from a mock *server*, never
//! against a mock that re-derives the thing under test.** Nothing in this module
//! may reimplement anything from `endpoints.rs` or `online.rs`.
//!
//! # Two generations
//!
//! [`FakeJellyfin::start`] takes the version string the fake server reports, and
//! the repository it hands back resolves its capabilities from exactly that — the
//! same path production takes. A test that runs against both generations is
//! therefore running the real resolution, not a stubbed one.
//!
//! TRACES: UR-085 | DR-281

use std::sync::Arc;

use serde_json::json;
use wiremock::matchers::{method, path_regex};
use wiremock::{Mock, MockServer, Request, ResponseTemplate};

use super::capabilities::ServerCapabilities;
use super::online::OnlineRepository;
use crate::jellyfin::{HttpClient, HttpConfig};

/// Jellyfin's current stable line, and the line this client was built against.
pub const V12: &str = "12.0.0";
pub const V10_11: &str = "10.11.5";

/// Both live generations. `#[test]`s that care about compatibility iterate this.
///
/// There is no 11 in the middle: Jellyfin dropped the leading `10` from its
/// scheme with 12.0, so what would have been 10.12.0 shipped as `12.0`.
pub const BOTH_GENERATIONS: [&str; 2] = [V10_11, V12];

pub struct FakeJellyfin {
    server: MockServer,
    version: String,
}

impl FakeJellyfin {
    /// Stand up a server reporting `version`, answering any `/Items`-shaped
    /// query with one item and any `/Users/.../Views` with one library.
    ///
    /// The response bodies are deliberately minimal: this module's job is to let
    /// tests observe what the *client* sent, not to re-specify Jellyfin.
    pub async fn start(version: &str) -> Self {
        let server = MockServer::start().await;

        let item = json!({
            "Id": "item-1",
            "Name": "A Film",
            "Type": "Movie",
            "IsFolder": false,
            "ServerId": "srv-1",
        });

        Mock::given(method("GET"))
            .and(path_regex(r".*/Views$"))
            .respond_with(ResponseTemplate::new(200).set_body_json(json!({
                "Items": [{
                    "Id": "lib-1",
                    "Name": "Movies",
                    "Type": "CollectionFolder",
                    "CollectionType": "movies",
                    "IsFolder": true,
                    "ServerId": "srv-1",
                }],
                "TotalRecordCount": 1,
            })))
            .mount(&server)
            .await;

        // Everything else that returns a listing.
        Mock::given(method("GET"))
            .respond_with(ResponseTemplate::new(200).set_body_json(json!({
                "Items": [item],
                "TotalRecordCount": 1,
            })))
            .mount(&server)
            .await;

        Mock::given(method("POST"))
            .respond_with(ResponseTemplate::new(204))
            .mount(&server)
            .await;

        Self {
            server,
            version: version.to_string(),
        }
    }

    /// A repository pointed at this server, with capabilities resolved from the
    /// version it reports — the same resolution production performs.
    pub fn repository(&self) -> OnlineRepository {
        let http = HttpClient::new_allowing_plaintext_for_tests(HttpConfig::default())
            .expect("test http client");

        OnlineRepository::new(
            Arc::new(http),
            self.server.uri(),
            "user-1".to_string(),
            "token-abc".to_string(),
        )
        .with_capabilities(ServerCapabilities::from_reported(&self.version))
    }

    /// Every request the server received, in order.
    pub async fn requests(&self) -> Vec<Request> {
        self.server
            .received_requests()
            .await
            .expect("request recording is enabled")
    }

    /// The single request received, failing loudly if there was not exactly one.
    pub async fn only_request(&self) -> Request {
        let mut received = self.requests().await;
        assert_eq!(
            received.len(),
            1,
            "expected exactly one request, got {}",
            received.len()
        );
        received.remove(0)
    }
}

/// The request target as the server saw it — path plus query.
pub fn target(request: &Request) -> String {
    match request.url.query() {
        Some(q) => format!("{}?{}", request.url.path(), q),
        None => request.url.path().to_string(),
    }
}