hjkl 0.21.5

use super::*;

// ── LSP diagnostics tests ────────────────────────────────────────────────

/// Build a `textDocument/publishDiagnostics` JSON payload for `file_url`
/// containing one error diagnostic.
#[test]
fn publish_diagnostics_populates_slot_diags() {
    let mut app = App::new(None, false, None, None).unwrap();

    // Give the active slot an absolute file path.
    let path = tmp_path("hjkl_diag_test.rs");
    app.active_mut().filename = Some(path.clone());

    seed_buffer(&mut app, "let x = ();\nlet y = ();");

    let params = pub_diags_params(
        &file_url(&path),
        serde_json::json!([{
            "range": {
                "start": { "line": 0, "character": 4 },
                "end":   { "line": 0, "character": 5 }
            },
            "severity": 1,
            "message": "unused variable",
            "source": "rustc",
            "code": "E0001"
        }]),
    );

    app.handle_publish_diagnostics(params);

    let slot = app.active();
    assert_eq!(slot.lsp_diags.len(), 1);
    let d = &slot.lsp_diags[0];
    assert_eq!(d.start_row, 0);
    assert_eq!(d.start_col, 4);
    assert_eq!(d.end_row, 0);
    assert_eq!(d.end_col, 5);
    assert_eq!(d.severity, DiagSeverity::Error);
    assert_eq!(d.message, "unused variable");
    assert_eq!(d.source.as_deref(), Some("rustc"));
    assert_eq!(d.code.as_deref(), Some("E0001"));

    // Gutter sign must be present for row 0.
    assert!(
        slot.diag_signs_lsp
            .iter()
            .any(|s| s.row == 0 && s.ch == 'E'),
        "expected an 'E' gutter sign for row 0"
    );
}

#[test]
fn publish_diagnostics_replaces_existing() {
    let mut app = App::new(None, false, None, None).unwrap();
    let path = tmp_path("hjkl_diag_replace.rs");
    app.active_mut().filename = Some(path.clone());
    seed_buffer(&mut app, "a\nb\nc");

    // First publish: two diags.
    let params1 = pub_diags_params(
        &file_url(&path),
        serde_json::json!([
            {
                "range": { "start": { "line": 0, "character": 0 }, "end": { "line": 0, "character": 1 } },
                "severity": 1,
                "message": "err A"
            },
            {
                "range": { "start": { "line": 1, "character": 0 }, "end": { "line": 1, "character": 1 } },
                "severity": 2,
                "message": "warn B"
            }
        ]),
    );
    app.handle_publish_diagnostics(params1);
    assert_eq!(app.active().lsp_diags.len(), 2);

    // Second publish: one diag — must replace, not append.
    let params2 = pub_diags_params(
        &file_url(&path),
        serde_json::json!([{
            "range": { "start": { "line": 2, "character": 0 }, "end": { "line": 2, "character": 1 } },
            "severity": 3,
            "message": "info C"
        }]),
    );
    app.handle_publish_diagnostics(params2);

    let slot = app.active();
    assert_eq!(
        slot.lsp_diags.len(),
        1,
        "second publish must replace, not append"
    );
    assert_eq!(slot.lsp_diags[0].message, "info C");
    assert_eq!(slot.lsp_diags[0].severity, DiagSeverity::Info);
    // Old signs must be replaced too.
    assert_eq!(slot.diag_signs_lsp.len(), 1);
    assert_eq!(slot.diag_signs_lsp[0].row, 2);
}

#[test]
fn publish_diagnostics_clears_on_empty() {
    let mut app = App::new(None, false, None, None).unwrap();
    let path = tmp_path("hjkl_diag_clear.rs");
    app.active_mut().filename = Some(path.clone());
    seed_buffer(&mut app, "a");

    let params_with = pub_diags_params(
        &file_url(&path),
        serde_json::json!([{
            "range": { "start": { "line": 0, "character": 0 }, "end": { "line": 0, "character": 1 } },
            "severity": 1,
            "message": "err"
        }]),
    );
    app.handle_publish_diagnostics(params_with);
    assert_eq!(app.active().lsp_diags.len(), 1);

    // Empty diagnostics array clears all diags.
    let params_clear = pub_diags_params(&file_url(&path), serde_json::json!([]));
    app.handle_publish_diagnostics(params_clear);

    let slot = app.active();
    assert!(slot.lsp_diags.is_empty(), "empty publish must clear diags");
    assert!(
        slot.diag_signs_lsp.is_empty(),
        "empty publish must clear gutter signs"
    );
}

#[test]
fn publish_diagnostics_ignores_unknown_uri() {
    let mut app = App::new(None, false, None, None).unwrap();
    let path = tmp_path("hjkl_diag_known.rs");
    app.active_mut().filename = Some(path.clone());
    seed_buffer(&mut app, "a");

    // Params targeting a *different* file — should be silently ignored.
    let unknown_path = tmp_path("hjkl_diag_unknown.rs");
    let params = pub_diags_params(
        &file_url(&unknown_path),
        serde_json::json!([{
            "range": { "start": { "line": 0, "character": 0 }, "end": { "line": 0, "character": 1 } },
            "severity": 1,
            "message": "err"
        }]),
    );
    app.handle_publish_diagnostics(params);

    assert!(
        app.active().lsp_diags.is_empty(),
        "unmatched URI must not populate diags"
    );
}

#[test]
fn lnext_jumps_to_next_diag() {
    let mut app = App::new(None, false, None, None).unwrap();
    let path = tmp_path("hjkl_lnext.rs");
    app.active_mut().filename = Some(path.clone());
    seed_buffer(&mut app, "a\nb\nc\nhello world");

    // Plant diags on rows 1 and 3.
    let params = pub_diags_params(
        &file_url(&path),
        serde_json::json!([
            {
                "range": { "start": { "line": 1, "character": 0 }, "end": { "line": 1, "character": 1 } },
                "severity": 1,
                "message": "first"
            },
            {
                "range": { "start": { "line": 3, "character": 6 }, "end": { "line": 3, "character": 11 } },
                "severity": 2,
                "message": "second"
            }
        ]),
    );
    app.handle_publish_diagnostics(params);

    // Cursor at row 0 — lnext should jump to row 1.
    app.lnext_severity(None);
    let (row, _col) = app.active().editor.cursor();
    assert_eq!(row, 1, "lnext must jump to first diag after cursor");

    // Cursor now at row 1 — lnext should jump to row 3.
    app.lnext_severity(None);
    let (row, col) = app.active().editor.cursor();
    assert_eq!(row, 3);
    assert_eq!(col, 6, "lnext must place cursor at diag start_col");
}

#[test]
fn gg_scrolls_window_viewport_to_top() {
    // Regression: gg moved cursor to (0,0) and the engine called
    // ensure_cursor_in_scrolloff, but the host's keymap-Unbound branch
    // forwarded the key to the engine WITHOUT calling
    // sync_viewport_from_editor — so the focused window's stored
    // top_row stayed at the old position.
    let mut app = App::new(None, false, None, None).unwrap();
    let lines: Vec<String> = (0..100).map(|i| format!("line {i}")).collect();
    seed_buffer(&mut app, &lines.join("\n"));

    // Position cursor + viewport deep in the buffer. The viewport_height
    // atomic must also be set — every vim::step resyncs vp.height from
    // it, so leaving the atomic at 0 would zero the host viewport mid-step
    // and disable scrolloff math.
    app.active_mut().editor.set_viewport_height(20);
    {
        let vp = app.active_mut().editor.host_mut().viewport_mut();
        vp.width = 80;
        vp.height = 20;
        vp.text_width = 80;
        vp.top_row = 60;
    }
    app.active_mut().editor.jump_cursor(70, 0);
    app.sync_viewport_from_editor();
    let fw = app.focused_window();
    assert_eq!(app.windows[fw].as_ref().unwrap().top_row, 60);

    // Drive `gg` through the engine. First `g` sets engine-side pending,
    // second `g` triggers the gg motion (cursor → top + auto-scroll).
    hjkl_vim::handle_key(
        &mut app.active_mut().editor,
        KeyEvent::new(KeyCode::Char('g'), KeyModifiers::NONE),
    );
    hjkl_vim::handle_key(
        &mut app.active_mut().editor,
        KeyEvent::new(KeyCode::Char('g'), KeyModifiers::NONE),
    );
    // The Unbound replay path in event_loop.rs syncs the editor's
    // auto-scrolled viewport back to the focused window.
    app.sync_viewport_from_editor();

    let (row, _col) = app.active().editor.cursor();
    assert_eq!(row, 0, "gg must put cursor at row 0");
    let stored_top = app.windows[fw].as_ref().unwrap().top_row;
    assert!(
        stored_top < 60,
        "gg must scroll window viewport to top, but stored top_row stayed at {stored_top}"
    );
}

#[test]
fn plus_slash_argv_scrolls_window_viewport_to_match() {
    // Regression: +/pat moved the cursor but didn't scroll the viewport,
    // so the rendered viewport stayed at row 0 and the cursor landed
    // off-screen on large files. Fix: App::new calls
    // ensure_cursor_in_scrolloff after the search and seeds the initial
    // window's top_row from the editor viewport.
    use std::io::Write;
    let dir = std::env::temp_dir().join("hjkl_plus_slash_scroll");
    std::fs::create_dir_all(&dir).unwrap();
    let path = dir.join("sample.rs");
    {
        let mut f = std::fs::File::create(&path).unwrap();
        // 100 lines of filler; first `target` match deep at row 80.
        for i in 0..100 {
            if i == 80 {
                writeln!(f, "fn target() {{}}").unwrap();
            } else {
                writeln!(f, "// padding line {i}").unwrap();
            }
        }
    }
    // Set viewport_height atomic via a fake App + apply_viewport_height
    // before the search runs. App::new builds the slot with
    // crossterm::terminal::size() — under tests that may return 0,
    // disabling scrolloff. Pre-set the atomic by dropping in via the
    // test helper.
    // Easier path: build a small file where the first match is on row 5
    // and assert window.top_row > 0 (proxy for "scrolled").
    let mut app = App::new(Some(path.clone()), false, None, Some("target".into())).unwrap();
    let (row, _col) = app.active().editor.cursor();
    assert_eq!(row, 80, "+/target must move cursor to row 80");
    // The window's stored top_row should reflect the editor's scrolled
    // viewport. With crossterm::terminal::size returning 0 in test
    // contexts the scroll math is a no-op, so set the height atomic
    // and re-run ensure_cursor_in_scrolloff to verify the scroll path.
    app.active_mut().editor.set_viewport_height(20);
    {
        let vp = app.active_mut().editor.host_mut().viewport_mut();
        vp.width = 80;
        vp.height = 20;
        vp.text_width = 80;
    }
    app.active_mut().editor.ensure_cursor_in_scrolloff();
    let editor_top = app.active().editor.host().viewport().top_row;
    assert!(
        editor_top > 0,
        "ensure_cursor_in_scrolloff should scroll editor viewport away from row 0; got top_row={editor_top}"
    );
    let _ = std::fs::remove_dir_all(&dir);
}

#[test]
fn slash_search_in_editor_scrolls_window_viewport() {
    // Regression: /pat<CR> in the editor moved the cursor but didn't
    // scroll the focused window's viewport, leaving the cursor
    // off-screen on large files.
    let mut app = App::new(None, false, None, None).unwrap();
    let lines: Vec<String> = (0..100)
        .map(|i| {
            if i == 80 {
                "target".into()
            } else {
                format!("line {i}")
            }
        })
        .collect();
    seed_buffer(&mut app, &lines.join("\n"));
    app.active_mut().editor.set_viewport_height(20);
    {
        let vp = app.active_mut().editor.host_mut().viewport_mut();
        vp.width = 80;
        vp.height = 20;
        vp.text_width = 80;
    }
    let fw = app.focused_window();
    // Cursor at (0,0), window.top_row=0. Run /target<CR>.
    app.commit_search("target");
    let stored_top = app.windows[fw].as_ref().unwrap().top_row;
    assert!(
        stored_top > 0,
        "/target<CR> should scroll the focused window's stored top_row past 0 to reveal the match"
    );
    let (row, _col) = app.active().editor.cursor();
    assert_eq!(row, 80, "/target<CR> should land cursor on row 80");
    // Counter must show 1/1 (cursor on the only match), not 0/1.
    let count = crate::render::search_count(&app);
    assert_eq!(
        count,
        Some((1, 1)),
        "search counter must update after /<CR>"
    );
    // Cursor must respect SCROLLOFF=5: cursor at row 80, height 20, so
    // viewport top_row should be such that screen row is between
    // [margin, height-1-margin] = [5, 14]. Specifically max_bottom=14
    // → top = 80 - 14 = 66.
    let stored_top = app.windows[fw].as_ref().unwrap().top_row;
    let screen_row = 80usize.saturating_sub(stored_top);
    assert!(
        (5..=14).contains(&screen_row),
        "scrolloff=5 violated: screen_row={screen_row} (top={stored_top}, cursor=80, height=20)"
    );
}

#[test]
fn plus_slash_argv_with_realistic_rust_source() {
    // Mirror the user's repro: hjkl +/main on a real-ish rust file.
    use std::io::Write;
    let dir = std::env::temp_dir().join("hjkl_plus_slash_real");
    std::fs::create_dir_all(&dir).unwrap();
    let path = dir.join("sample.rs");
    {
        let mut f = std::fs::File::create(&path).unwrap();
        // Real-ish content. First `main` substring is on row 5 (`fn main`).
        writeln!(f, "//! crate root").unwrap(); // row 0
        writeln!(f).unwrap(); // row 1
        writeln!(f, "use std::path::PathBuf;").unwrap();
        writeln!(f).unwrap();
        writeln!(f, "/// Entry.").unwrap();
        writeln!(f, "fn main() {{").unwrap(); // row 5: first 'main'
        writeln!(f, "    let _ = main_helper();").unwrap(); // row 6: 'main_helper'
        writeln!(f, "}}").unwrap();
        writeln!(f, "fn main_helper() {{}}").unwrap(); // row 8: 'main_helper'
    }
    let app = App::new(Some(path.clone()), false, None, Some("main".into())).unwrap();
    let (row, _col) = app.active().editor.cursor();
    assert_eq!(
        row, 5,
        "+/main on rust source must land on row 5 (first `fn main`), got row {row}"
    );
    let _ = std::fs::remove_dir_all(&dir);
}

#[test]
fn plus_slash_argv_search_lands_on_first_forward_match() {
    // Regression: hjkl +/main file.rs lands cursor on a match in the
    // backward direction (or wraps incorrectly) because the +/<pat>
    // path advanced from cursor=(0,0) and the wrap policy mishandles
    // the at-or-after invariant.
    use std::io::Write;
    let dir = std::env::temp_dir().join("hjkl_plus_slash_test");
    std::fs::create_dir_all(&dir).unwrap();
    let path = dir.join("sample.txt");
    {
        let mut f = std::fs::File::create(&path).unwrap();
        // 3 matches at known rows. First match at row 2.
        writeln!(f, "alpha").unwrap();
        writeln!(f, "beta").unwrap();
        writeln!(f, "main one").unwrap();
        writeln!(f, "delta").unwrap();
        writeln!(f, "main two").unwrap();
        writeln!(f, "main three").unwrap();
    }
    let app = App::new(Some(path.clone()), false, None, Some("main".into())).unwrap();
    let (row, col) = app.active().editor.cursor();
    assert_eq!(
        row, 2,
        "+/main must land on the FIRST forward match (row 2), got row {row}"
    );
    assert_eq!(col, 0);
    let _ = std::fs::remove_dir_all(&dir);
}

#[test]
fn plus_slash_argv_search_with_goto_line_searches_forward() {
    // hjkl +5 +/main file.rs : goto_line first, then search forward.
    use std::io::Write;
    let dir = std::env::temp_dir().join("hjkl_plus_slash_goto_test");
    std::fs::create_dir_all(&dir).unwrap();
    let path = dir.join("sample.txt");
    {
        let mut f = std::fs::File::create(&path).unwrap();
        writeln!(f, "main early").unwrap(); // row 0
        writeln!(f, "two").unwrap();
        writeln!(f, "three").unwrap();
        writeln!(f, "four").unwrap();
        writeln!(f, "five").unwrap(); // goto_line(5) lands here (1-based row 4)
        writeln!(f, "six").unwrap();
        writeln!(f, "main mid").unwrap(); // row 6
        writeln!(f, "main late").unwrap(); // row 7
    }
    // +5 goto_line=5 then +/main forward search. Should land on row 6,
    // NOT wrap back to row 0.
    let app = App::new(Some(path.clone()), false, Some(5), Some("main".into())).unwrap();
    let (row, _col) = app.active().editor.cursor();
    assert_eq!(
        row, 6,
        "+5 +/main must search forward from row 4, landing on row 6"
    );
    let _ = std::fs::remove_dir_all(&dir);
}

#[test]
fn plus_slash_argv_persists_forward_direction_for_n() {
    // Regression: `hjkl +/keyword file` did not call set_last_search,
    // so vim.last_search_forward stayed at its bool default (false).
    // The next `n` then computed forward = false != false = false and
    // jumped BACKWARD as if `?keyword<CR>` had been typed.
    use hjkl_engine::{Input, Key};
    use std::io::Write;
    let dir = std::env::temp_dir().join("hjkl_plus_slash_n_dir");
    std::fs::create_dir_all(&dir).unwrap();
    let path = dir.join("sample.txt");
    {
        let mut f = std::fs::File::create(&path).unwrap();
        writeln!(f, "alpha").unwrap(); // 0
        writeln!(f, "beta").unwrap(); // 1
        writeln!(f, "main one").unwrap(); // 2 — first match
        writeln!(f, "delta").unwrap(); // 3
        writeln!(f, "main two").unwrap(); // 4 — `n` should jump here
        writeln!(f, "main three").unwrap(); // 5
    }
    let mut app = App::new(Some(path.clone()), false, None, Some("main".into())).unwrap();
    let (row0, _) = app.active().editor.cursor();
    assert_eq!(row0, 2, "+/main must land on first match (row 2)");
    // last_search must be persisted so `n` knows the pattern.
    assert_eq!(app.active().editor.last_search(), Some("main"));
    // Drive `n` through the engine vim FSM and assert FORWARD jump.
    let n_input = Input {
        key: Key::Char('n'),
        ..Default::default()
    };
    hjkl_vim::dispatch_input(&mut app.active_mut().editor, n_input);
    let (row1, _) = app.active().editor.cursor();
    assert_eq!(
        row1, 4,
        "after +/main, `n` must advance FORWARD to row 4 (got row {row1}); \
        backward would land on row 0 (no match) or stay/regress"
    );
    let _ = std::fs::remove_dir_all(&dir);
}

#[test]
fn search_count_cursor_on_match_stays_on_match() {
    // Regression: /<pat><CR> from a cursor that's already ON a match used
    // to advance past it (counter 1/3 → 2/3). Vim semantics: /<CR> finds
    // the first match AT-OR-AFTER the cursor — only `n` advances.
    let mut app = App::new(None, false, None, None).unwrap();
    seed_buffer(&mut app, "foo X foo X foo");
    {
        let vp = app.active_mut().editor.host_mut().viewport_mut();
        vp.height = 5;
        vp.top_row = 0;
    }
    // Cursor at (0,0) — exactly on the first 'foo'.
    app.commit_search("foo");
    assert_eq!(
        crate::render::search_count(&app),
        Some((1, 3)),
        "/<pat><CR> from cursor on a match must keep counter at 1/3, \
        not advance to 2/3"
    );
}

#[test]
fn search_count_n_press_increments_by_one() {
    // After /foo<CR> lands on M1, pressing n should advance to M2 (counter 2/3).
    // If counter skips to 3/3, the n-jump is double-stepping.
    let mut app = App::new(None, false, None, None).unwrap();
    seed_buffer(&mut app, "X foo X foo X foo");
    {
        let vp = app.active_mut().editor.host_mut().viewport_mut();
        vp.height = 5;
        vp.top_row = 0;
    }
    app.commit_search("foo");
    assert_eq!(crate::render::search_count(&app), Some((1, 3)));
    // Now drive `n` via the engine.
    app.active_mut().editor.search_advance_forward(true);
    assert_eq!(
        crate::render::search_count(&app),
        Some((2, 3)),
        "n must advance counter from 1/3 to 2/3, not skip"
    );
    app.active_mut().editor.search_advance_forward(true);
    assert_eq!(crate::render::search_count(&app), Some((3, 3)));
}

#[test]
fn search_count_handles_multibyte_chars_before_match() {
    // Regression: search_count compared cursor_col (char index) against
    // m.start() (byte offset). A match on a line with multi-byte chars
    // before it (e.g. an em-dash in a doc comment) had byte > char, so
    // the inequality `(row, byte) <= (row, char)` falsely excluded the
    // match the cursor was sitting on — counter showed 0/N instead of 1/N.
    //
    // Real-world repro: `/main` in apps/hjkl/src/main.rs landed on a
    // line "/// surface them — `main` prints …" with an em-dash and
    // showed [0/6] on commit, then [2/6] after one `n` press.
    let mut app = App::new(None, false, None, None).unwrap();
    // Two matches; first sits behind a multi-byte em-dash.
    seed_buffer(&mut app, "alpha\n/// — main one\nbeta\nmain two");
    {
        let vp = app.active_mut().editor.host_mut().viewport_mut();
        vp.height = 10;
        vp.top_row = 0;
    }
    app.commit_search("main");
    assert_eq!(
        crate::render::search_count(&app),
        Some((1, 2)),
        "/main must land on M1 with counter 1/2, even when M1 sits \
        behind a multi-byte char (em-dash) on its line"
    );
    // n -> M2 -> 2/2.
    app.active_mut().editor.search_advance_forward(true);
    assert_eq!(crate::render::search_count(&app), Some((2, 2)));
}

#[test]
fn search_count_through_full_key_flow() {
    // Regression: simulate the actual key path / -> 'f' -> 'o' -> 'o' -> Enter.
    // Counter must end at 1/3 (or N/3 with N=1), never skipping past 1.
    let mut app = App::new(None, false, None, None).unwrap();
    seed_buffer(&mut app, "X foo X foo X foo");
    {
        let vp = app.active_mut().editor.host_mut().viewport_mut();
        vp.height = 5;
        vp.top_row = 0;
    }
    // Open / prompt.
    app.open_search_prompt(crate::app::SearchDir::Forward);
    // Type 'f' 'o' 'o' through handle_search_field_key.
    for ch in ['f', 'o', 'o'] {
        let key = KeyEvent::new(KeyCode::Char(ch), KeyModifiers::NONE);
        app.handle_search_field_key(key);
    }
    // During typing the counter should be 0/3 (cursor before all matches).
    let count = crate::render::search_count(&app);
    assert_eq!(count, Some((0, 3)), "during typing, counter must be 0/3");
    // Submit.
    let enter = KeyEvent::new(KeyCode::Enter, KeyModifiers::NONE);
    app.handle_search_field_key(enter);
    // After submit the counter must show 1/3, NOT 2/3.
    let count = crate::render::search_count(&app);
    assert_eq!(
        count,
        Some((1, 3)),
        "after / submit, counter must be 1/3 — bug was 2/3"
    );
}

#[test]
fn search_count_after_commit_lands_on_first_match() {
    // Regression: `/<pat><CR>` from a non-match cursor was incrementing
    // the match counter to 2 (skipping 1) because commit_search passed
    // skip_current=true even on the first jump.
    let mut app = App::new(None, false, None, None).unwrap();
    seed_buffer(&mut app, "X foo X foo X foo");
    // Cursor at (0,0), 'X' — before all matches.
    {
        let vp = app.active_mut().editor.host_mut().viewport_mut();
        vp.height = 5;
        vp.top_row = 0;
    }
    // Submit `/foo<CR>` programmatically.
    app.commit_search("foo");
    // Counter should now show 1/3 (first match), not 2/3.
    let count = crate::render::search_count(&app);
    assert_eq!(
        count,
        Some((1, 3)),
        "/{{pat}}<CR> from a non-match cursor must land on match 1, not skip to 2"
    );
}

#[test]
fn lsp_jump_reveals_cursor_in_viewport() {
    // Regression: jump_cursor only sets cursor; without ensure_cursor_in_
    // scrolloff afterwards, the viewport stays parked and the cursor lands
    // off-screen. Plant a diag past the visible area, jump, assert the
    // window's stored top_row scrolled.
    use crate::app::window::WindowId;

    let mut app = App::new(None, false, None, None).unwrap();
    let path = tmp_path("hjkl_jump_scroll.rs");
    app.active_mut().filename = Some(path.clone());

    // 100 lines of content so a row-50 jump is well past any default
    // viewport.
    let lines: Vec<String> = (0..100).map(|i| format!("line {i}")).collect();
    seed_buffer(&mut app, &lines.join("\n"));

    // Set the focused window's viewport height + reset scroll so we can
    // observe whether jump scrolls.
    {
        let vp = app.active_mut().editor.host_mut().viewport_mut();
        vp.height = 20;
        vp.top_row = 0;
    }
    let fw: WindowId = app.focused_window();
    if let Some(w) = app.windows[fw].as_mut() {
        w.top_row = 0;
    }

    // Plant a diagnostic on row 50 and jump to it.
    let params = pub_diags_params(
        &file_url(&path),
        serde_json::json!([{
            "range": { "start": { "line": 50, "character": 0 }, "end": { "line": 50, "character": 1 } },
            "severity": 1,
            "message": "deep"
        }]),
    );
    app.handle_publish_diagnostics(params);
    app.lnext_severity(None);

    // Cursor must be at row 50 AND the viewport must have scrolled past
    // the original top_row=0 so the cursor is visible.
    let (row, _) = app.active().editor.cursor();
    assert_eq!(row, 50);
    let vp_top = app.active().editor.host().viewport().top_row;
    assert!(
        vp_top > 0,
        "viewport top_row stayed at 0 after jump — ensure_cursor_in_scrolloff not called"
    );
    let stored_top = app.windows[fw].as_ref().unwrap().top_row;
    assert!(
        stored_top > 0,
        "focused window's stored top_row stayed at 0 — sync_viewport_from_editor missed the scroll"
    );
}

#[test]
fn lprev_jumps_to_prev_diag_with_wrap() {
    let mut app = App::new(None, false, None, None).unwrap();
    let path = tmp_path("hjkl_lprev.rs");
    app.active_mut().filename = Some(path.clone());
    seed_buffer(&mut app, "a\nb\nc\nd");

    let params = pub_diags_params(
        &file_url(&path),
        serde_json::json!([
            {
                "range": { "start": { "line": 0, "character": 0 }, "end": { "line": 0, "character": 1 } },
                "severity": 1,
                "message": "first"
            },
            {
                "range": { "start": { "line": 2, "character": 1 }, "end": { "line": 2, "character": 2 } },
                "severity": 2,
                "message": "second"
            }
        ]),
    );
    app.handle_publish_diagnostics(params);

    // Cursor at row 0 col 0 — lprev should wrap to the last diag (row 2).
    app.lprev_severity(None);
    let (row, _) = app.active().editor.cursor();
    assert_eq!(row, 2, "lprev from first diag must wrap to last");

    // Cursor now at row 2 — lprev should jump to row 0.
    app.lprev_severity(None);
    let (row, _) = app.active().editor.cursor();
    assert_eq!(row, 0, "lprev must jump to previous diag");
}

#[test]
fn lnext_severity_skips_lower_severity() {
    let mut app = App::new(None, false, None, None).unwrap();
    let path = tmp_path("hjkl_lnext_sev.rs");
    app.active_mut().filename = Some(path.clone());
    seed_buffer(&mut app, "a\nb\nc");

    // Row 1: Warning, Row 2: Error.
    let params = pub_diags_params(
        &file_url(&path),
        serde_json::json!([
            {
                "range": { "start": { "line": 1, "character": 0 }, "end": { "line": 1, "character": 1 } },
                "severity": 2,
                "message": "warn"
            },
            {
                "range": { "start": { "line": 2, "character": 0 }, "end": { "line": 2, "character": 1 } },
                "severity": 1,
                "message": "err"
            }
        ]),
    );
    app.handle_publish_diagnostics(params);

    // Jump to Error-only — must skip Warning on row 1 and land on row 2.
    app.lnext_severity(Some(DiagSeverity::Error));
    let (row, _) = app.active().editor.cursor();
    assert_eq!(row, 2, "lnext with Error filter must skip Warning diags");
}

#[test]
fn lopen_shows_no_diags_message_when_empty() {
    let mut app = App::new(None, false, None, None).unwrap();
    app.open_diag_picker();
    // No diagnostics — picker must not open; status message set.
    assert!(app.picker.is_none(), "picker must not open when no diags");
    let msg = app.status_message.clone().unwrap_or_default();
    assert!(
        msg.contains("no diagnostics"),
        "expected 'no diagnostics', got: {msg}"
    );
}

#[test]
fn lopen_lists_diags_in_picker() {
    let mut app = App::new(None, false, None, None).unwrap();
    let path = tmp_path("hjkl_lopen.rs");
    app.active_mut().filename = Some(path.clone());
    seed_buffer(&mut app, "a\nb");

    let params = pub_diags_params(
        &file_url(&path),
        serde_json::json!([{
            "range": { "start": { "line": 0, "character": 0 }, "end": { "line": 0, "character": 1 } },
            "severity": 1,
            "message": "some error"
        }]),
    );
    app.handle_publish_diagnostics(params);

    app.open_diag_picker();
    assert!(app.picker.is_some(), "picker must open when diags exist");
}

#[test]
fn lsp_info_with_lsp_disabled_sets_status() {
    let mut app = App::new(None, false, None, None).unwrap();
    // self.lsp is None by default — :LspInfo shows the disabled state.
    app.show_lsp_info();
    let popup = app.info_popup.clone().unwrap_or_default();
    assert!(
        popup.contains("LSP: disabled"),
        "expected 'LSP: disabled' message, got: {popup}"
    );
}

#[test]
fn lsp_info_lists_running_servers() {
    let mut app = App::new(None, false, None, None).unwrap();
    // Need an LspManager attached so :LspInfo doesn't show "disabled".
    app.lsp = Some(hjkl_lsp::LspManager::spawn(hjkl_lsp::LspConfig::default()));
    // Manually insert a fake server into lsp_state.
    let key = hjkl_lsp::ServerKey {
        language: "rust".into(),
        root: std::path::PathBuf::from("/tmp/proj"),
    };
    app.lsp_state.insert(
        key,
        LspServerInfo {
            initialized: true,
            capabilities: serde_json::json!({}),
        },
    );

    app.show_lsp_info();
    assert!(
        app.info_popup.is_some(),
        "popup must open when LSP is enabled"
    );
    let popup = app.info_popup.as_ref().unwrap();
    assert!(popup.contains("rust"), "popup must mention server language");
    assert!(
        popup.contains("initialized"),
        "popup must show server state"
    );
    if let Some(mgr) = app.lsp.take() {
        mgr.shutdown();
    }
}

#[test]
fn notify_change_skipped_when_dirty_gen_unchanged() {
    // Without a real LspManager we can't exercise the full path, but we
    // *can* verify that the last_lsp_dirty_gen guard does not reset on
    // repeated calls with no edits: the gen stays the same, so the
    // second call would be a no-op (it would return early). We assert
    // the guard value is set correctly after a manual seed.
    let mut app = App::new(None, false, None, None).unwrap();
    // No LSP manager attached — lsp_notify_change_active returns early.
    // Manually set last_lsp_dirty_gen to simulate a prior send.
    let dg = app.active().editor.buffer().dirty_gen();
    app.active_mut().last_lsp_dirty_gen = Some(dg);

    // Call again — must not panic and must not reset the guard.
    app.lsp_notify_change_active();
    assert_eq!(
        app.active().last_lsp_dirty_gen,
        Some(dg),
        "guard must remain unchanged when no LSP manager"
    );
}

// ── Phase 3: goto + hover tests ────────────────────────────────────────────

#[test]
fn goto_definition_single_jumps_cursor() {
    let mut app = App::new(None, false, None, None).unwrap();
    seed_buffer(&mut app, "line0\nline1\nline2\nline3");
    // Give the active slot a path so the location URI matches.
    let path = tmp_path("hjkl_gd_single.rs");
    app.active_mut().filename = Some(path.clone());
    let uri = file_url(&path);

    let loc = make_location(&uri, 2, 0);
    let result = ok_val(serde_json::to_value(vec![loc]).unwrap());
    let buffer_id = app.active().buffer_id as hjkl_lsp::BufferId;
    app.handle_goto_response(buffer_id, (0, 0), result, "definition");

    // Cursor must have moved to row 2.
    assert_eq!(app.active().editor.buffer().cursor().row, 2);
    assert!(app.picker.is_none(), "single result must not open picker");
}

#[test]
fn goto_definition_empty_sets_status() {
    let mut app = App::new(None, false, None, None).unwrap();
    let result = ok_val(serde_json::Value::Null);
    let buffer_id = app.active().buffer_id as hjkl_lsp::BufferId;
    app.handle_goto_response(buffer_id, (0, 0), result, "definition");

    let msg = app.status_message.as_deref().unwrap_or("");
    assert!(
        msg.contains("no definition found"),
        "expected 'no definition found', got: {msg}"
    );
    assert!(app.picker.is_none());
}

#[test]
fn goto_definition_multi_opens_picker() {
    let mut app = App::new(None, false, None, None).unwrap();
    // Use platform-aware URIs so Windows CI runners don't strip drive letters.
    let locs = vec![
        make_location(&file_url(&tmp_path("hjkl_gd_multi_a.rs")), 0, 0),
        make_location(&file_url(&tmp_path("hjkl_gd_multi_b.rs")), 5, 3),
        make_location(&file_url(&tmp_path("hjkl_gd_multi_c.rs")), 10, 1),
    ];
    let result = ok_val(serde_json::to_value(locs).unwrap());
    let buffer_id = app.active().buffer_id as hjkl_lsp::BufferId;
    app.handle_goto_response(buffer_id, (0, 0), result, "definition");

    assert!(app.picker.is_some(), "multiple results must open picker");
}

#[test]
fn goto_references_always_opens_picker() {
    let mut app = App::new(None, false, None, None).unwrap();
    // Single result — references always opens picker.
    // Use platform-aware URI so Windows CI runners don't strip drive letters.
    let locs = vec![make_location(&file_url(&tmp_path("hjkl_gd_only.rs")), 3, 0)];
    let result = ok_val(serde_json::to_value(locs).unwrap());
    let buffer_id = app.active().buffer_id as hjkl_lsp::BufferId;
    app.handle_references_response(buffer_id, (0, 0), result);

    assert!(app.picker.is_some(), "references must always open picker");
}

#[test]
fn hover_response_sets_info_popup() {
    let mut app = App::new(None, false, None, None).unwrap();
    let hover = lsp_types::Hover {
        contents: lsp_types::HoverContents::Markup(lsp_types::MarkupContent {
            kind: lsp_types::MarkupKind::Markdown,
            value: "**fn** foo() -> i32".to_string(),
        }),
        range: None,
    };
    let result = ok_val(serde_json::to_value(hover).unwrap());
    let buffer_id = app.active().buffer_id as hjkl_lsp::BufferId;
    app.handle_hover_response(buffer_id, (0, 0), result);

    assert!(app.info_popup.is_some(), "hover must set info_popup");
    let popup = app.info_popup.as_ref().unwrap();
    assert!(popup.contains("foo"), "popup must contain function name");
}

#[test]
fn hover_empty_sets_status() {
    let mut app = App::new(None, false, None, None).unwrap();
    let result: Result<serde_json::Value, hjkl_lsp::RpcError> = Ok(serde_json::Value::Null);
    let buffer_id = app.active().buffer_id as hjkl_lsp::BufferId;
    app.handle_hover_response(buffer_id, (0, 0), result);

    let msg = app.status_message.as_deref().unwrap_or("");
    assert!(
        msg.contains("no hover info"),
        "expected 'no hover info', got: {msg}"
    );
    assert!(app.info_popup.is_none());
}

#[test]
fn goto_definition_error_sets_status() {
    let mut app = App::new(None, false, None, None).unwrap();
    let result = err_val("server error");
    let buffer_id = app.active().buffer_id as hjkl_lsp::BufferId;
    app.handle_goto_response(buffer_id, (0, 0), result, "definition");

    let msg = app.status_message.as_deref().unwrap_or("");
    assert!(
        msg.contains("server error"),
        "expected error message, got: {msg}"
    );
}

#[test]
fn k_dispatches_hover() {
    // Without a real LspManager the call returns early with a status hint.
    let mut app = App::new(None, false, None, None).unwrap();
    app.active_mut().filename = Some(tmp_path("k_test.rs"));
    app.lsp_hover();
    assert!(app.info_popup.is_none());
    let msg = app.status_message.as_deref().unwrap_or("");
    assert!(msg.contains("LSP: not enabled"), "got: {msg}");
}

#[test]
fn gd_dispatches_goto_definition() {
    // Without a real LspManager the call returns early (no panic).
    let mut app = App::new(None, false, None, None).unwrap();
    app.active_mut().filename = Some(tmp_path("gd_test.rs"));
    app.lsp_goto_definition();
    // No LSP — nothing pending, no crash.
    assert!(app.lsp_pending.is_empty());
}

#[test]
fn lsp_request_works_with_relative_filename() {
    // Regression: opening hjkl with a relative path like
    // `apps/hjkl/src/main.rs` used to silently fail to attach to the LSP
    // server because url::Url::from_file_path requires absolute paths.
    // The absolutize() helper now joins relative paths against
    // current_dir() before URI conversion.
    let mut app = App::new(None, false, None, None).unwrap();
    let mgr = hjkl_lsp::LspManager::spawn(hjkl_lsp::LspConfig::default());
    app.lsp = Some(mgr);
    app.active_mut().filename = Some(std::path::PathBuf::from("src/main.rs"));
    app.lsp_goto_definition();
    // Request was registered as pending — absolutize made URI conversion
    // succeed even though the buffer's filename is relative.
    assert_eq!(
        app.lsp_pending.len(),
        1,
        "relative-path goto must produce a pending request, not the \
        'no file open' error path"
    );
    if let Some(mgr) = app.lsp.take() {
        mgr.shutdown();
    }
}

// ── Phase 4: completion popup tests ────────────────────────────────────────

#[test]
fn completion_response_opens_popup() {
    let mut app = App::new(None, false, None, None).unwrap();
    // Enter insert mode so the guard passes.
    hjkl_vim::handle_key(&mut app.active_mut().editor, key(KeyCode::Char('i')));
    // Give the buffer a filename so buffer_id matches.
    app.active_mut().filename = Some(std::path::PathBuf::from("/tmp/test.rs"));
    let buffer_id = app.active().buffer_id as hjkl_lsp::BufferId;

    let response_val = synthesize_completion_response(&["foo", "bar", "baz"]);
    app.handle_completion_response(buffer_id, 0, 0, Ok(response_val));

    assert!(app.completion.is_some(), "popup should open");
    let popup = app.completion.as_ref().unwrap();
    assert_eq!(popup.all_items.len(), 3);
    assert_eq!(popup.visible.len(), 3);
}

#[test]
fn completion_response_empty_no_popup() {
    let mut app = App::new(None, false, None, None).unwrap();
    hjkl_vim::handle_key(&mut app.active_mut().editor, key(KeyCode::Char('i')));
    app.active_mut().filename = Some(std::path::PathBuf::from("/tmp/test.rs"));
    let buffer_id = app.active().buffer_id as hjkl_lsp::BufferId;

    // Empty list response.
    let response_val = serde_json::json!([]);
    app.handle_completion_response(buffer_id, 0, 0, Ok(response_val));

    assert!(
        app.completion.is_none(),
        "empty response must not open popup"
    );
    assert!(
        app.status_message
            .as_deref()
            .unwrap_or("")
            .contains("no completions"),
        "status should report no completions"
    );
}

#[test]
fn completion_request_pending_routes_to_handler() {
    let mut app = App::new(None, false, None, None).unwrap();
    // Simulate a pending completion request.
    hjkl_vim::handle_key(&mut app.active_mut().editor, key(KeyCode::Char('i')));
    app.active_mut().filename = Some(std::path::PathBuf::from("/tmp/test.rs"));
    let buffer_id = app.active().buffer_id as hjkl_lsp::BufferId;

    // Insert a fake pending request.
    let req_id = app.lsp_alloc_request_id();
    app.lsp_pending.insert(
        req_id,
        LspPendingRequest::Completion {
            buffer_id,
            anchor_row: 0,
            anchor_col: 0,
        },
    );

    // Simulate receiving a response.
    let response_val = synthesize_completion_response(&["alpha", "beta"]);
    let pending = app.lsp_pending.remove(&req_id).unwrap();
    app.handle_lsp_response(pending, Ok(response_val));

    assert!(
        app.completion.is_some(),
        "response must route to popup opener"
    );
    let popup = app.completion.as_ref().unwrap();
    assert_eq!(popup.all_items.len(), 2);
}

#[test]
fn accept_completion_inserts_selected_item() {
    let mut app = App::new(None, false, None, None).unwrap();
    // Seed buffer with some text and enter insert mode at col 0.
    seed_buffer(&mut app, "fn foo");
    hjkl_vim::handle_key(&mut app.active_mut().editor, key(KeyCode::Char('i')));
    // Open popup anchored at col 0 row 0 with two items.
    let items = vec![make_completion_item("hello"), make_completion_item("world")];
    app.completion = Some(crate::completion::Completion::new(0, 0, items));
    // Select second item.
    app.completion.as_mut().unwrap().selected = 1;

    app.accept_completion();
    app.sync_after_engine_mutation();

    // Popup must be gone.
    assert!(app.completion.is_none());
    // Buffer line should start with "world" (inserted at col 0).
    let line = app.active().editor.buffer().lines()[0].clone();
    assert!(
        line.starts_with("world"),
        "buffer line should start with inserted text, got: {line:?}"
    );
    // Sync footer must have drained dirty + content_edits.
    assert!(
        !app.active_mut().editor.take_dirty(),
        "accept_completion call site must drain dirty via sync_after_engine_mutation"
    );
    assert!(
        app.active_mut().editor.take_content_edits().is_empty(),
        "accept_completion call site must drain content_edits"
    );
}

#[test]
fn dismiss_completion_clears_state() {
    let mut app = App::new(None, false, None, None).unwrap();
    let items = vec![make_completion_item("foo")];
    app.completion = Some(crate::completion::Completion::new(0, 0, items));
    app.pending_ctrl_x = true;

    app.dismiss_completion();

    assert!(app.completion.is_none());
    assert!(!app.pending_ctrl_x);
}

#[test]
fn set_prefix_dismisses_when_filter_empty() {
    // Open popup, set prefix that matches nothing → popup auto-dismisses.
    let items = vec![make_completion_item("alpha"), make_completion_item("beta")];
    let mut popup = crate::completion::Completion::new(0, 0, items);
    popup.set_prefix("xyz");
    assert!(
        popup.is_empty(),
        "popup should be empty after non-matching prefix"
    );
}

// ── Phase 5 LSP tests ────────────────────────────────────────────────────

#[test]
#[allow(clippy::mutable_key_type)]
fn apply_workspace_edit_single_file() {
    let path = std::env::temp_dir().join("hjkl_ws_edit_single.txt");
    std::fs::write(&path, "hello world\n").unwrap();
    let mut app = App::new(Some(path.clone()), false, None, None).unwrap();

    let uri = file_url(&path);
    let edit = make_workspace_edit(&uri, 0, 6, 0, 11, "rust");
    let count = app
        .apply_workspace_edit(edit)
        .expect("apply_workspace_edit failed");
    assert_eq!(count, 1);

    let lines = app.active().editor.buffer().lines();
    assert_eq!(
        lines[0], "hello rust",
        "edit should replace 'world' with 'rust'"
    );
    let _ = std::fs::remove_file(&path);
}

#[test]
#[allow(clippy::mutable_key_type)]
fn apply_workspace_edit_sorts_edits_descending() {
    // Two edits on the same line: first edit at col 0-3, second at col 6-11.
    // If applied in forward order the offsets shift; descending order must give correct result.
    let path = std::env::temp_dir().join("hjkl_ws_edit_sort.txt");
    std::fs::write(&path, "hello world foo\n").unwrap();
    let mut app = App::new(Some(path.clone()), false, None, None).unwrap();

    let url = file_url(&path)
        .parse::<lsp_types::Uri>()
        .expect("valid URI");
    let mut changes = std::collections::HashMap::new();
    changes.insert(
        url,
        vec![
            // Edit 1: replace "hello" (0-5) with "hi"
            lsp_types::TextEdit {
                range: lsp_types::Range {
                    start: lsp_types::Position {
                        line: 0,
                        character: 0,
                    },
                    end: lsp_types::Position {
                        line: 0,
                        character: 5,
                    },
                },
                new_text: "hi".to_string(),
            },
            // Edit 2: replace "world" (6-11) with "earth"
            lsp_types::TextEdit {
                range: lsp_types::Range {
                    start: lsp_types::Position {
                        line: 0,
                        character: 6,
                    },
                    end: lsp_types::Position {
                        line: 0,
                        character: 11,
                    },
                },
                new_text: "earth".to_string(),
            },
        ],
    );
    let edit = lsp_types::WorkspaceEdit {
        changes: Some(changes),
        document_changes: None,
        change_annotations: None,
    };
    app.apply_workspace_edit(edit).expect("apply failed");
    let lines = app.active().editor.buffer().lines();
    assert_eq!(lines[0], "hi earth foo", "both edits must apply correctly");
    let _ = std::fs::remove_file(&path);
}

#[test]
#[allow(clippy::mutable_key_type)]
fn apply_workspace_edit_multi_file() {
    let path_a = std::env::temp_dir().join("hjkl_ws_multi_a.txt");
    let path_b = std::env::temp_dir().join("hjkl_ws_multi_b.txt");
    std::fs::write(&path_a, "file a content\n").unwrap();
    std::fs::write(&path_b, "file b content\n").unwrap();

    let mut app = App::new(Some(path_a.clone()), false, None, None).unwrap();

    let uri_a = file_url(&path_a);
    let uri_b = file_url(&path_b);

    let url_a = uri_a.parse::<lsp_types::Uri>().expect("valid URI a");
    let url_b = uri_b.parse::<lsp_types::Uri>().expect("valid URI b");
    let mut changes = std::collections::HashMap::new();
    changes.insert(
        url_a,
        vec![lsp_types::TextEdit {
            range: lsp_types::Range {
                start: lsp_types::Position {
                    line: 0,
                    character: 7,
                },
                end: lsp_types::Position {
                    line: 0,
                    character: 14,
                },
            },
            new_text: "edited".to_string(),
        }],
    );
    changes.insert(
        url_b,
        vec![lsp_types::TextEdit {
            range: lsp_types::Range {
                start: lsp_types::Position {
                    line: 0,
                    character: 7,
                },
                end: lsp_types::Position {
                    line: 0,
                    character: 14,
                },
            },
            new_text: "changed".to_string(),
        }],
    );

    let edit = lsp_types::WorkspaceEdit {
        changes: Some(changes),
        document_changes: None,
        change_annotations: None,
    };
    let count = app
        .apply_workspace_edit(edit)
        .expect("multi-file apply failed");
    assert_eq!(count, 2, "should affect 2 files");
    let _ = std::fs::remove_file(&path_a);
    let _ = std::fs::remove_file(&path_b);
}

#[test]
fn rename_response_null_sets_status() {
    let mut app = App::new(None, false, None, None).unwrap();
    let pending = LspPendingRequest::Rename {
        buffer_id: 0,
        anchor_row: 0,
        anchor_col: 0,
        new_name: "newName".to_string(),
    };
    app.handle_lsp_response(pending, Ok(serde_json::Value::Null));
    let msg = app.status_message.clone().unwrap_or_default();
    assert!(
        msg.contains("cannot rename"),
        "null rename must set 'cannot rename' status, got: {msg}"
    );
}

#[test]
fn rename_response_applies_workspace_edit() {
    let path = std::env::temp_dir().join("hjkl_rename_apply.txt");
    std::fs::write(&path, "old_name here\n").unwrap();
    let mut app = App::new(Some(path.clone()), false, None, None).unwrap();

    let uri = file_url(&path);
    let edit = make_workspace_edit(&uri, 0, 0, 0, 8, "new_name");
    let val = serde_json::to_value(edit).unwrap();

    let pending = LspPendingRequest::Rename {
        buffer_id: 0,
        anchor_row: 0,
        anchor_col: 0,
        new_name: "new_name".to_string(),
    };
    app.handle_lsp_response(pending, Ok(val));
    let msg = app.status_message.clone().unwrap_or_default();
    assert!(
        msg.contains("renamed"),
        "rename response must set status, got: {msg}"
    );
    let lines = app.active().editor.buffer().lines();
    assert_eq!(lines[0], "new_name here");
    let _ = std::fs::remove_file(&path);
}

#[test]
fn format_response_empty_sets_status() {
    let mut app = App::new(None, false, None, None).unwrap();
    let pending = LspPendingRequest::Format {
        buffer_id: 0,
        range: None,
    };
    // Empty array = no changes.
    app.handle_lsp_response(pending, Ok(serde_json::json!([])));
    let msg = app.status_message.clone().unwrap_or_default();
    assert!(
        msg.contains("no formatting"),
        "empty format response must say 'no formatting changes', got: {msg}"
    );
}

#[test]
fn format_response_applies_text_edits() {
    let path = std::env::temp_dir().join("hjkl_format_apply.txt");
    std::fs::write(&path, "fn foo(){}\n").unwrap();
    let mut app = App::new(Some(path.clone()), false, None, None).unwrap();
    let buf_id = app.active().buffer_id as hjkl_lsp::BufferId;

    // Insert a space at col 9 (after the `{`) → "fn foo(){ }"
    let edits: Vec<lsp_types::TextEdit> = vec![lsp_types::TextEdit {
        range: lsp_types::Range {
            start: lsp_types::Position {
                line: 0,
                character: 9,
            },
            end: lsp_types::Position {
                line: 0,
                character: 9,
            },
        },
        new_text: " ".to_string(),
    }];
    let val = serde_json::to_value(&edits).unwrap();

    let pending = LspPendingRequest::Format {
        buffer_id: buf_id,
        range: None,
    };
    app.handle_lsp_response(pending, Ok(val));
    let msg = app.status_message.clone().unwrap_or_default();
    assert_eq!(msg, "formatted");
    let lines = app.active().editor.buffer().lines();
    // "fn foo(){}" with space inserted at pos 9 → "fn foo(){ }"
    assert_eq!(lines[0], "fn foo(){ }");
    let _ = std::fs::remove_file(&path);
}

#[test]
fn code_action_response_empty_sets_status() {
    let mut app = App::new(None, false, None, None).unwrap();
    let pending = LspPendingRequest::CodeAction {
        buffer_id: 0,
        anchor_row: 0,
        anchor_col: 0,
    };
    app.handle_lsp_response(pending, Ok(serde_json::json!([])));
    let msg = app.status_message.clone().unwrap_or_default();
    assert!(
        msg.contains("no code actions"),
        "empty code actions must say 'no code actions', got: {msg}"
    );
}

#[test]
fn code_action_response_multi_opens_picker() {
    let mut app = App::new(None, false, None, None).unwrap();
    let pending = LspPendingRequest::CodeAction {
        buffer_id: 0,
        anchor_row: 0,
        anchor_col: 0,
    };
    let actions = serde_json::json!([
        {
            "title": "Fix import",
            "kind": "quickfix",
        },
        {
            "title": "Extract method",
            "kind": "refactor",
        },
    ]);
    app.handle_lsp_response(pending, Ok(actions));
    assert!(
        app.picker.is_some(),
        "multiple code actions must open picker"
    );
    assert_eq!(
        app.pending_code_actions.len(),
        2,
        "pending_code_actions must hold both actions"
    );
}

#[test]
fn code_action_response_single_applies_action() {
    let path = std::env::temp_dir().join("hjkl_ca_single.txt");
    std::fs::write(&path, "old content\n").unwrap();
    let mut app = App::new(Some(path.clone()), false, None, None).unwrap();

    let uri = file_url(&path);
    let edit = make_workspace_edit(&uri, 0, 0, 0, 11, "new content");
    let action = lsp_types::CodeAction {
        title: "Replace content".to_string(),
        edit: Some(edit),
        ..Default::default()
    };
    let val =
        serde_json::to_value(vec![lsp_types::CodeActionOrCommand::CodeAction(action)]).unwrap();

    let pending = LspPendingRequest::CodeAction {
        buffer_id: 0,
        anchor_row: 0,
        anchor_col: 0,
    };
    app.handle_lsp_response(pending, Ok(val));
    // Single action: applied directly, no picker.
    assert!(
        app.picker.is_none(),
        "single code action must not open picker"
    );
    let msg = app.status_message.clone().unwrap_or_default();
    assert!(
        msg.contains("files changed"),
        "single action apply must set status, got: {msg}"
    );
    let lines = app.active().editor.buffer().lines();
    assert_eq!(lines[0], "new content");
    let _ = std::fs::remove_file(&path);
}

#[test]
fn lsp_code_actions_includes_overlapping_diags_in_context() {
    // Verify that lsp_code_actions collects diagnostics that overlap the cursor.
    // We set up a slot with diags and check the request would include them.
    // Since we can't intercept the LspManager send, we test the diagnostic
    // overlap logic used by lsp_code_actions separately here.
    let mut app = App::new(None, false, None, None).unwrap();
    seed_buffer(&mut app, "fn foo() {\n    let x = 1;\n}\n");

    // Seed two diagnostics: one overlapping the cursor, one not.
    app.active_mut().lsp_diags = vec![
        LspDiag {
            start_row: 0,
            start_col: 3,
            end_row: 0,
            end_col: 6,
            severity: DiagSeverity::Error,
            message: "overlapping".to_string(),
            source: None,
            code: None,
        },
        LspDiag {
            start_row: 1,
            start_col: 0,
            end_row: 1,
            end_col: 5,
            severity: DiagSeverity::Warning,
            message: "not overlapping".to_string(),
            source: None,
            code: None,
        },
    ];

    // Position cursor at row=0, col=4 (inside the first diag range).
    app.active_mut().editor.jump_cursor(0, 4);

    // Test the overlap logic directly.
    let cursor_row = 0usize;
    let cursor_col = 4usize;
    let diags = &app.active().lsp_diags;
    let overlapping: Vec<_> = diags
        .iter()
        .filter(|d| {
            let after_start = (cursor_row, cursor_col) >= (d.start_row, d.start_col);
            let before_end = cursor_row < d.end_row
                || (cursor_row == d.end_row && cursor_col < d.end_col)
                || (cursor_row == d.start_row && d.start_row == d.end_row);
            after_start && (before_end || cursor_row == d.start_row)
        })
        .collect();

    assert_eq!(
        overlapping.len(),
        1,
        "only the overlapping diag should be included"
    );
    assert_eq!(overlapping[0].message, "overlapping");
}