//! The WAP family: XHTML Mobile Profile, and the `text/html` body derived from it.
//!
//! One crate rather than one per format, because the HTML form is the XHTML-MP
//! bytes with the XML declaration removed, and because WML's deck configuration
//! is shared with nothing outside this family. Splitting them would duplicate the
//! escaper and the markup builder.

mod escape;
mod xhtmlmp;

use itsybitsy_core::Error;
use itsybitsy_core::ir::Doc;
use itsybitsy_core::render::{RenderCtx, Rendered, Renderer};

/// XHTML Mobile Profile, for WAP 2.0 clients: well-formed XML with the prolog.
pub struct XhtmlMp;

impl Renderer for XhtmlMp {
    fn id(&self) -> &'static str {
        "xhtmlmp"
    }

    fn media_type(&self) -> &'static str {
        "application/vnd.wap.xhtml+xml; charset=utf-8"
    }

    fn render(&self, doc: &Doc, ctx: &RenderCtx<'_>) -> Result<Rendered, Error> {
        Ok(Rendered::body(xhtmlmp::document(doc, ctx.title, true).into_bytes()))
    }
}

/// The same markup served as `text/html`, for an ordinary browser.
pub struct Html;

impl Renderer for Html {
    fn id(&self) -> &'static str {
        "html"
    }

    fn media_type(&self) -> &'static str {
        "text/html; charset=utf-8"
    }

    fn render(&self, doc: &Doc, ctx: &RenderCtx<'_>) -> Result<Rendered, Error> {
        Ok(Rendered::body(xhtmlmp::document(doc, ctx.title, false).into_bytes()))
    }
}

#[cfg(test)]
mod tests {
    use itsybitsy_core::config::PageSettings;
    use itsybitsy_core::parse;

    use super::*;

    fn render(renderer: &dyn Renderer, markdown: &str) -> String {
        let doc = parse::markdown(markdown);
        let settings = PageSettings::default();
        let ctx = RenderCtx { url: "/x", title: "The Title", settings: &settings, width: None };
        String::from_utf8(renderer.render(&doc, &ctx).unwrap().body).unwrap()
    }

    fn body(markdown: &str) -> String {
        let out = render(&Html, markdown);
        let start = out.find("<body>\n").unwrap() + "<body>\n".len();
        let end = out.find("</body>").unwrap();
        out[start..end].to_string()
    }

    #[test]
    fn the_html_form_carries_no_xml_declaration() {
        // A browser parsing this as text/html tolerates the declaration as a
        // bogus comment and renders the page, but logs a warning for it.
        let out = render(&Html, "# a\n");
        assert!(!out.starts_with("<?xml"));
        assert!(out.starts_with("<!DOCTYPE html"));
    }

    #[test]
    fn the_xhtml_form_keeps_it_because_wap_clients_need_valid_xml() {
        assert!(render(&XhtmlMp, "# a\n").starts_with("<?xml version=\"1.0\""));
    }

    #[test]
    fn the_two_forms_differ_only_in_that_line() {
        let xml = render(&XhtmlMp, "# a\n\ntext\n");
        let html = render(&Html, "# a\n\ntext\n");
        assert_eq!(&xml[xml.find("<!DOCTYPE").unwrap()..], html);
    }

    #[test]
    fn the_resolved_title_reaches_the_head() {
        assert!(render(&Html, "# ignored\n").contains("<title>The Title</title>"));
    }

    #[test]
    fn blocks_become_their_markup() {
        assert_eq!(body("# a\n"), "<h1>a</h1>\n");
        assert_eq!(body("###### f\n"), "<h6>f</h6>\n");
        assert_eq!(body("text\n"), "<p>text</p>\n");
        assert_eq!(body("---\n"), "<hr/>\n");
        assert_eq!(body("> q\n"), "<blockquote>\n<p>q</p>\n</blockquote>\n");
        assert_eq!(body("```\nx\n```\n"), "<pre>x</pre>\n");
    }

    #[test]
    fn lists_keep_a_single_paragraph_item_inline() {
        assert_eq!(body("- a\n- b\n"), "<ul>\n<li>a</li>\n<li>b</li>\n</ul>\n");
        assert_eq!(body("1. a\n"), "<ol>\n<li>a</li>\n</ol>\n");
    }

    #[test]
    fn inline_markup_becomes_elements() {
        assert_eq!(
            body("a *b* **c** `d`\n"),
            "<p>a <em>b</em> <strong>c</strong> <code>d</code></p>\n"
        );
    }

    #[test]
    fn strikethrough_keeps_its_text_since_the_profile_has_no_element_for_it() {
        assert_eq!(body("~~gone~~\n"), "<p>gone</p>\n");
    }

    #[test]
    fn links_and_images_carry_their_attributes() {
        assert_eq!(body("[label](/x \"T\")\n"), "<p><a href=\"/x\" title=\"T\">label</a></p>\n");
        assert_eq!(body("![alt](/i.png)\n"), "<p><img src=\"/i.png\" alt=\"alt\"/></p>\n");
    }

    #[test]
    fn markup_characters_in_text_are_escaped() {
        assert_eq!(body("a < b & c\n"), "<p>a &lt; b &amp; c</p>\n");
        assert_eq!(body("[x](/a?b=1&c=2)\n"), "<p><a href=\"/a?b=1&amp;c=2\">x</a></p>\n");
    }

    #[test]
    fn tables_become_tables() {
        assert_eq!(
            body("| h |\n| --- |\n| c |\n"),
            "<table>\n<tr><th>h</th></tr>\n<tr><td>c</td></tr>\n</table>\n"
        );
    }

    #[test]
    fn art_keeps_its_label_as_a_title() {
        let doc = Doc {
            blocks: vec![itsybitsy_core::ir::Block::Art {
                alt: "Dragon".into(),
                lines: vec!["/\\".into()],
            }],
            first_h1: None,
        };
        let settings = PageSettings::default();
        let ctx = RenderCtx { url: "/x", title: "T", settings: &settings, width: None };
        let out = String::from_utf8(Html.render(&doc, &ctx).unwrap().body).unwrap();
        assert!(out.contains("<pre title=\"Dragon\">/\\</pre>"), "{out}");
    }

    #[test]
    fn raw_html_is_passed_through_because_it_is_already_the_right_language() {
        assert_eq!(body("<div>x</div>\n"), "<div>x</div>\n");
    }

    #[test]
    fn a_card_divider_emits_nothing() {
        let doc = Doc {
            blocks: vec![itsybitsy_core::ir::Block::CardBreak { title: Some("W".into()) }],
            first_h1: None,
        };
        let settings = PageSettings::default();
        let ctx = RenderCtx { url: "/x", title: "T", settings: &settings, width: None };
        let out = String::from_utf8(Html.render(&doc, &ctx).unwrap().body).unwrap();
        assert!(out.contains("<body>\n</body>"), "{out}");
    }
}