//! The user dashboard's Support panel, described.
//!
//! Third of the tier-1 batch (wiki `mnw-server-conversion-plan`, "The S4 tab
//! inventory"): 63 lines, one form, no `data-action`, no `<details>`, and
//! nothing in `static/` or `frontend/src` reaches for any id it writes.
//!
//! A fill rather than a mounted screen, following [`super::user_projects`]:
//! `dashboard_tab_support` is the Askama handler and stays, and this is what it
//! answers. Unlike Projects there is no ETag to preserve here; the reason is
//! the other one, which is that Support is one of the four panels the dashboard
//! page can render inline, so it needs a [`fill`] either way and a mounted
//! screen would leave the inline path with nothing to call.
//!
//! # It closes part of `736f45a5`, and that is the point worth recording
//!
//! The template's submit button carried `<span id="support-spinner"
//! class="htmx-indicator"> ...</span>`, and the form carried
//! `hx-indicator="#support-spinner"` to drive it. Both are gone:
//! [`Action::awaiting`] says the same thing in one word, the renderer draws the
//! wait and locks the control, and no screen has to spell an indicator or
//! invent an id for one.
//!
//! That is three of the 122 spelling sites `736f45a5` counted (one
//! `htmx-indicator`, one `hx-indicator`, one `id="...spinner"`). The task
//! predicted the conversions would take them for free and this is one
//! conversion doing it.
//!
//! # What the description says that the markup did not
//!
//! The category `<select>` opened with `<option value="" disabled selected>`, a
//! markup idiom for "nothing chosen yet" that a description says by the field
//! simply having no value. Six real options remain, and a renderer that is not
//! a browser no longer has to know that one of the seven was a placeholder.
//!
//! The response-times block stays prose. It is three durations and a mailto,
//! not a set of things with addresses, so it is [`Node::rich`] carrying the
//! source rather than a described list: a terminal renders the same three lines
//! without being handed `<ul>`.

use makeover_layout as layout;
use quasi_router::screen::{Choice, Field};
use quasi_router::{Action, Node, RegionKind, Slot};
use quasi_webview::Webview;

/// The region the answer replaces, keeping the id the page already used.
pub const REGION: &str = "user-support";

/// Where a ticket goes.
const TICKET: &str = "/api/support/ticket";

/// The region the answer lands in, which the form aims at and the page leaves
/// empty until something is submitted.
const RESULT: &str = "support-result";

/// The panel as the route answers it: the region, carrying its own id.
#[must_use]
pub fn fragment(email: &str) -> String {
    use quasi_axum::Serves as _;

    let mut slot = Slot::new(REGION, RegionKind::Pane);
    for node in body(email) {
        slot = slot.with(node);
    }
    Webview::new().fragment(&Node::Region(slot))
}

/// The panel's contents as the page embeds them, without a region wrapper.
#[must_use]
pub fn fill(email: &str) -> String {
    use quasi_axum::Serves as _;

    let mut out = String::new();
    for node in body(email) {
        out.push_str(&Webview::new().fragment(&node));
    }
    out
}

/// The panel's contents, in order.
fn body(email: &str) -> Vec<Node> {
    vec![
        Node::section("Support"),
        Node::text(
            "Every response is from a real person. We will never use AI to handle your questions.",
        ),
        Node::text(format!(
            "We monitor the platform proactively and may have already opened a ticket for your \
             issue. Check your email at {email} before submitting."
        )),
        ticket_form(),
        // Where the answer lands. Named by the form's own action, and empty
        // until something is submitted.
        Node::Region(Slot::new(RESULT, RegionKind::Pane)),
        response_times(),
    ]
}

/// The ticket form.
fn ticket_form() -> Node {
    Node::Form {
        // `awaiting` is the whole of what `hx-indicator="#support-spinner"` and
        // the span it pointed at were doing. See the module header.
        action: Action::post(TICKET).awaiting(),
        submit: "Submit".into(),
        fields: vec![
            Field::select("category", "Category", categories()).required(),
            length(
                placeholder(
                    Field::new(layout::FieldKind::Text, "subject", "Subject").required(),
                    "Brief description of the issue",
                ),
                200,
            ),
            length(
                placeholder(
                    Field::new(layout::FieldKind::Textarea, "message", "Message").required(),
                    "What happened? What did you expect? Include any relevant details.",
                ),
                5000,
            ),
        ],
    }
}

/// What a ticket can be about.
///
/// The template's seventh option was `value=""`, disabled and selected: the
/// markup spelling of "nothing chosen yet". A field with no value says it, so
/// only the six real categories are here.
fn categories() -> Vec<Choice> {
    [
        ("bug", "Bug report"),
        ("billing", "Billing or payments"),
        ("account", "Account access"),
        ("content", "Content or uploads"),
        ("security", "Security concern"),
        ("other", "Other"),
    ]
    .into_iter()
    .map(|(value, label)| Choice::new(value, label))
    .collect()
}

/// How long an answer takes, and the way round the queue for a security issue.
fn response_times() -> Node {
    super::own_prose(
        "Response times:\n\n\
         - Security issues: same day\n\
         - Billing and account access: 24 hours\n\
         - Everything else: 1-2 business days\n\n\
         For urgent security issues, email <security@makenot.work> directly.",
    )
}

/// Set a field's placeholder. A plain field assignment, since `Field` has no
/// builder for it and the field is public.
fn placeholder(mut field: Field, text: &str) -> Field {
    field.placeholder = Some(text.to_owned());
    field
}

/// Cap what a field accepts, matching the template's `maxlength`.
///
/// Kept rather than dropped: it is the same limit the API validates against, and
/// a form that lets a reader type 6000 characters before refusing them is worse
/// than one that stops at 5000.
fn length(mut field: Field, max: u32) -> Field {
    field.max_length = Some(max);
    field
}

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

    fn render() -> String {
        let mut out = String::new();
        for node in &body("ada@example.com") {
            out.push_str(&Webview::new().fragment(node));
        }
        out
    }

    #[test]
    fn the_form_addresses_a_route_the_api_answers() {
        // The S3 failure class: a control addressing a route registered nowhere
        // renders fine and answers 404 when pressed.
        let api = include_str!("../routes/api/mod.rs");
        assert!(api.contains(TICKET), "registered route");
    }

    #[test]
    fn the_readers_own_address_is_shown_and_escaped() {
        let html = render();
        assert!(html.contains("ada@example.com"), "{html}");

        let mut out = String::new();
        for node in &body("<script>x()</script>") {
            out.push_str(&Webview::new().fragment(node));
        }
        assert!(!out.contains("<script>x()"), "{out}");
    }

    #[test]
    fn every_category_is_offered_and_the_placeholder_option_is_not() {
        let html = render();

        for label in [
            "Bug report",
            "Billing or payments",
            "Account access",
            "Content or uploads",
            "Security concern",
            "Other",
        ] {
            assert!(html.contains(label), "missing {label}: {html}");
        }
        // The template's disabled `value=""` seventh option.
        assert!(!html.contains("Select a category"), "{html}");
    }

    #[test]
    fn the_wait_is_said_once_and_no_spinner_is_spelled() {
        let html = render();

        // What `736f45a5` is counting. None of the three spellings survive.
        assert!(!html.contains("htmx-indicator"), "{html}");
        assert!(!html.contains("hx-indicator"), "{html}");
        assert!(!html.contains("spinner"), "{html}");
    }

    #[test]
    fn both_free_text_fields_carry_the_limit_the_api_validates() {
        let html = render();
        assert!(html.contains("maxlength=\"200\""), "{html}");
        assert!(html.contains("maxlength=\"5000\""), "{html}");
    }

    #[test]
    fn the_answer_has_somewhere_to_land() {
        let html = render();
        assert!(html.contains(&format!("id=\"{RESULT}\"")), "{html}");
    }

    #[test]
    fn the_inline_fill_carries_no_region_because_the_strip_draws_one() {
        let inline = fill("ada@example.com");
        assert!(!inline.contains(&format!("id=\"{REGION}\"")), "{inline}");
        assert!(inline.contains("Support"), "{inline}");
    }
}