//! Pasting a URL over selected text makes a markdown link; every other paste
//! stays a plain paste.

use notescraft_editor::keys::{self, Edit};

fn applied(text: &str, edit: &Edit) -> String {
    let mut out = String::from(text);
    out.replace_range(edit.range.clone(), &edit.insert);
    out
}

fn link(text: &str, range: std::ops::Range<usize>, pasted: &str) -> Option<String> {
    keys::on_paste_url(text, range, pasted).map(|edit| applied(text, &edit))
}

const URL: &str = "https://example.com";

#[test]
fn a_plain_word_becomes_a_link() {
    let text = "hello world";
    assert_eq!(link(text, 6..11, URL), Some(String::from("hello [world](https://example.com)")));
}

#[test]
fn a_phrase_becomes_a_link() {
    let text = "the quick brown fox";
    assert_eq!(link(text, 4..15, URL), Some(String::from("the [quick brown](https://example.com) fox")));
}

#[test]
fn the_cursor_ends_after_the_closing_paren() {
    let text = "hello world";
    let edit = keys::on_paste_url(text, 6..11, URL).unwrap();
    assert_eq!(edit.sel, 34..34);
    assert_eq!(edit.range, 6..11);
}

#[test]
fn brackets_in_the_selection_are_escaped() {
    let text = "a [b] c";
    assert_eq!(link(text, 0..7, URL), Some(String::from("[a \\[b\\] c](https://example.com)")));
}

#[test]
fn a_wrapped_selection_keeps_its_label() {
    let text = "[label](old)";
    assert_eq!(link(text, 0..12, URL), Some(String::from("[label](https://example.com)")));
    let text = "[label]";
    assert_eq!(link(text, 0..7, URL), Some(String::from("[label](https://example.com)")));
}

#[test]
fn an_angle_bracketed_url_is_unwrapped() {
    let text = "hello world";
    assert_eq!(link(text, 6..11, "<https://example.com>"), Some(String::from("hello [world](https://example.com)")));
}

#[test]
fn other_schemes_are_refused() {
    let text = "hello";
    assert!(link(text, 0..5, "javascript:alert(1)").is_none());
    assert!(link(text, 0..5, "file:///etc/passwd").is_none());
    assert!(link(text, 0..5, "mailto:me@example.com").is_none());
}

#[test]
fn a_url_with_spaces_is_refused() {
    let text = "hello";
    assert!(link(text, 0..5, "https://example.com/a b").is_none());
}

#[test]
fn a_host_without_a_dot_is_refused() {
    let text = "hello";
    assert!(link(text, 0..5, "http://example").is_none());
    assert!(link(text, 0..5, "http://localhost:8080/x").is_some());
}

#[test]
fn the_scheme_is_case_insensitive() {
    let text = "hello";
    assert!(link(text, 0..5, "HTTPS://EXAMPLE.COM").is_some());
}

#[test]
fn a_url_over_2048_bytes_is_refused() {
    let text = "hello";
    let fits = format!("https://example.com/{}", "x".repeat(2028));
    assert_eq!(fits.len(), 2048);
    assert!(link(text, 0..5, &fits).is_some());
    let too_long = format!("https://example.com/{}", "x".repeat(2029));
    assert!(link(text, 0..5, &too_long).is_none());
}

#[test]
fn an_empty_selection_is_refused() {
    let text = "hello world";
    assert!(link(text, 6..6, URL).is_none());
}

#[test]
fn a_selection_inside_a_fenced_block_is_refused() {
    let text = "```rust\nfn main() {}\n```";
    let start = text.find("fn main").unwrap();
    assert!(link(text, start..start + 9, URL).is_none());
}

#[test]
fn a_selection_inside_inline_code_is_refused() {
    let text = "a `code` b";
    let start = text.find("code").unwrap();
    assert!(link(text, start..start + 4, URL).is_none());
}

#[test]
fn a_selection_inside_a_link_is_refused() {
    let text = "[label](https://example.com)";
    let start = text.find("label").unwrap();
    assert!(link(text, start..start + 5, URL).is_none());
}

#[test]
fn a_multi_line_selection_is_refused() {
    let text = "one\ntwo";
    assert!(link(text, 0..7, URL).is_none());
}

#[test]
fn a_selection_over_500_bytes_is_refused() {
    let text = "x".repeat(501);
    assert!(link(&text, 0..501, URL).is_none());
    let text = "x".repeat(500);
    assert!(link(&text, 0..500, URL).is_some());
}

#[test]
fn a_selection_that_is_a_url_pastes_normally() {
    let text = "https://example.com";
    assert!(link(text, 0..19, URL).is_none());
}

#[test]
fn unicode_offsets_are_kept() {
    let text = "caf\u{e9} na\u{ef}ve";
    let start = text.find("na\u{ef}ve").unwrap();
    let (head, tail) = text.split_at_checked(start).unwrap();
    assert_eq!(head, "caf\u{e9} ");
    assert_eq!(tail, "na\u{ef}ve");
    assert_eq!(link(text, start..start + tail.len(), URL), Some(String::from("caf\u{e9} [na\u{ef}ve](https://example.com)")));
}

#[test]
fn a_second_paste_changes_nothing() {
    let text = "hello world";
    let edit = keys::on_paste_url(text, 6..11, URL).unwrap();
    let linked = applied(text, &edit);
    assert_eq!(keys::on_paste_url(text, 6..11, URL), Some(edit.clone()));
    assert!(keys::on_paste_url(&linked, edit.sel.clone(), URL).is_none());
}