zshrs 0.11.4

//! ZLE history operations
//!
//! Direct port from zsh/Src/Zle/zle_hist.c
//!
//! Previous aborted search string use in an incremental search              // c:52
//! Local keymap in isearch mode                                             // c:57
//! the last vi search                                                       // c:1807
//! history-beginning-search-backward                                        // c:2035
//! history-beginning-search-forward                                         // c:2082
//!
//! Implements all history navigation widgets:
//! - up-line-or-history, down-line-or-history
//! - history-search-backward, history-search-forward  
//! - history-incremental-search-backward, history-incremental-search-forward
//! - beginning-of-history, end-of-history
//! - vi-fetch-history, vi-history-search-*
//! - accept-line-and-down-history, accept-and-infer-next-history
//! - insert-last-word, push-line, push-line-or-edit

use std::sync::atomic::AtomicI32;

use super::zle_main::{ZleString};

// =====================================================================
// Isearch globals — `Src/Zle/zle_hist.c:1078`.
// =====================================================================

/// Port of `int isearch_active` from `Src/Zle/zle_hist.c:1078`.
/// Non-zero while the user is inside an incremental-search session.

// --- AUTO: cross-zle hoisted-fn use glob ---
#[allow(unused_imports)]
use crate::ported::zle::zle_h::*;
#[allow(unused_imports)]
use crate::ported::zle::zle_main::*;
#[allow(unused_imports)]
use crate::ported::zle::zle_misc::*;
#[allow(unused_imports)]
use crate::ported::zle::zle_move::*;
#[allow(unused_imports)]
use crate::ported::zle::zle_word::*;
#[allow(unused_imports)]
use crate::ported::zle::zle_params::*;
#[allow(unused_imports)]
use crate::ported::zle::zle_vi::*;
#[allow(unused_imports)]
use crate::ported::zle::zle_utils::*;
#[allow(unused_imports)]
use crate::ported::zle::zle_refresh::*;
#[allow(unused_imports)]
use crate::ported::zle::zle_tricky::*;
#[allow(unused_imports)]
use crate::ported::zle::textobjects::*;
#[allow(unused_imports)]
use crate::ported::zle::deltochar::*;

pub static ISEARCH_ACTIVE: AtomicI32 = AtomicI32::new(0);                    // c:1078

/// Port of `int isearch_startpos` from `Src/Zle/zle_hist.c:1078`.
/// Byte offset of the start of the current isearch match.
pub static ISEARCH_STARTPOS: AtomicI32 = AtomicI32::new(0);                  // c:1078

/// Port of `int isearch_endpos` from `Src/Zle/zle_hist.c:1078`.
/// Byte offset of the end of the current isearch match.
pub static ISEARCH_ENDPOS: AtomicI32 = AtomicI32::new(0);                    // c:1078

// Per-session ZLE history state. Rust-side aggregate over zsh's C
// flat-globals (`hist_ring`/`histline`/`searchstr`/`have_edits`/etc.
// in `Src/hist.c` + `Src/Zle/zle_hist.c`). The C side spreads these
// across file-scope statics; the zshrs port collects the subset the
// ZLE widgets actually drive into one container so a `&mut Zle` can
// hold it. Eventual unification: drop `History.entries` and read from
// `crate::ported::hist::hist_ring`; the cursor/saved_line/search
// fields stay as file-scope statics matching zsh's globals.

/// Single history entry — the Rust-side subset the ZLE widgets need
/// (line text, event number, optional time). Maps loosely to fields
/// from `struct histent` (Src/zsh.h:2234): `node.nam` ↔ `line`,
/// `histnum` ↔ `num`, `stim` ↔ `time`.
#[derive(Debug, Clone)]
pub struct HistEntry {
    /// The command line.
    pub line: String,
    /// Event number (1-based; mirrors `histent.histnum`).
    pub num: i64,
    /// Insertion time (Unix epoch seconds; mirrors `histent.stim`).
    pub time: Option<i64>,
}

/// Per-session ZLE history state — entries + cursor + search state.
/// Aggregate over zsh's C flat-globals (`hist_ring`, `histline`,
/// `searchstr`, `have_edits`).
#[derive(Debug, Default)]
pub struct History {
    /// History entries (newest last).
    pub entries: Vec<HistEntry>,
    /// Current position in history (mirrors `histline`).
    pub cursor: usize,
    /// Maximum history size (mirrors `histsiz`).
    pub max_size: usize,
    /// Saved line when navigating history (mirrors the C `zle_text`
    /// shadow on `Histent`).
    pub saved_line: Option<crate::ported::zle::zle_main::ZleString>,
    /// Saved cursor position pre-navigation.
    pub saved_cs: usize,
    /// Previous search string. Mirrors `searchstr`
    /// (Src/Zle/zle_hist.c:44).
    pub search_pattern: String,
    /// Last search direction (true = backward).
    pub search_backward: bool,
    /// Originals of edited entries: when `remember_edits` mutates
    /// `entries[i].line`, the pre-edit text lands here at index `i`.
    /// `forget_edits` restores them. Mirrors the C `Histent->zle_text`
    /// shadow string + the global `have_edits` flag in
    /// Src/Zle/zle_hist.c.
    pub originals: Vec<Option<String>>,
    /// True if any entry has a recorded original — mirrors
    /// `have_edits` in Src/Zle/zle_hist.c:76.
    pub have_edits: bool,
    /// History skip-flags state. Bit-equivalent of zsh's
    /// `hist_skip_flags` in Src/Zle/zle_hist.c:794: `HIST_FOREIGN` (1)
    /// hides entries from other sessions when set; `setlocalhistory`
    /// toggles this.
    pub hist_skip_flags: u32,
}

impl History {
    /// Construct an empty history with a max-entry cap. Mirrors the
    /// role of `inithist()` from Src/hist.c:1717 (which sizes the
    /// global `hist_ring` at `$HISTSIZE`).
    pub fn new(max_size: usize) -> Self {
        History {
            entries: Vec::new(),
            cursor: 0,
            max_size,
            saved_line: None,
            saved_cs: 0,
            search_pattern: String::new(),
            search_backward: true,
            originals: Vec::new(),
            have_edits: false,
            hist_skip_flags: 0,
        }
    }

    /// Append a new entry. Mirrors `addhistnode()` from Src/hist.c
    /// (the inner add path invoked by `addhistline`/`hend`). Skips
    /// empty input and consecutive-duplicate lines (same as zsh's
    /// HIST_IGNORE_DUPS default). Trims from the front when over
    /// `max_size`.
    pub fn add(&mut self, line: String) {
        if line.is_empty() {
            return;
        }
        if let Some(last) = self.entries.last() {
            if last.line == line {
                return;
            }
        }

        self.entries.push(HistEntry {
            line,
            num: self.entries.len() as i64 + 1,
            time: Some(
                std::time::SystemTime::now()
                    .duration_since(std::time::UNIX_EPOCH)
                    .map(|d| d.as_secs() as i64)
                    .unwrap_or(0),
            ),
        });

        while self.entries.len() > self.max_size {
            self.entries.remove(0);
        }

        self.cursor = self.entries.len();
    }

    /// Look up the entry at a specific 0-based index. Mirrors
    /// `quietgethist()` from Src/Zle/zle_hist.c:1712 (event-number
    /// fetch); our entries Vec is 0-indexed so callers convert
    /// num→index themselves.
    pub fn get(&self, index: usize) -> Option<&HistEntry> {
        self.entries.get(index)
    }

    /// Step the cursor one position older. Equivalent to the
    /// cursor-decrement path of `zle_goto_hist()` at
    /// Src/Zle/zle_hist.c:805 with n=-1.
    pub fn up(&mut self) -> Option<&HistEntry> {
        if self.cursor > 0 {
            self.cursor -= 1;
            self.entries.get(self.cursor)
        } else {
            None
        }
    }

    /// Step the cursor one position newer. Mirrors
    /// `zle_goto_hist()` at Src/Zle/zle_hist.c:805 with n=+1.
    pub fn down(&mut self) -> Option<&HistEntry> {
        if self.cursor < self.entries.len() {
            self.cursor += 1;
            self.entries.get(self.cursor)
        } else {
            None
        }
    }

    /// Search history for the most recent entry containing `pattern`.
    /// Substring-match equivalent of `historysearchbackward()` from
    /// Src/Zle/zle_hist.c:484 (without the glob/HIST_PATTERN branch).
    pub fn search_backward(&mut self, pattern: &str) -> Option<&HistEntry> {
        let start = if self.cursor > 0 {
            self.cursor - 1
        } else {
            return None;
        };
        for i in (0..=start).rev() {
            if self.entries[i].line.contains(pattern) {
                self.cursor = i;
                return self.entries.get(i);
            }
        }
        None
    }

    /// Search history forward for the next entry containing
    /// `pattern`. Mirror of `search_backward` against
    /// `historysearchforward()` at Src/Zle/zle_hist.c:541.
    pub fn search_forward(&mut self, pattern: &str) -> Option<&HistEntry> {
        for i in (self.cursor + 1)..self.entries.len() {
            if self.entries[i].line.contains(pattern) {
                self.cursor = i;
                return self.entries.get(i);
            }
        }
        None
    }

    /// Reset the cursor to the live-buffer sentinel position and
    /// drop any saved pre-navigation line. Mirrors the
    /// `histline = curhist; saved_line = NULL` reset path invoked by
    /// `endofhistory()` (Src/Zle/zle_hist.c:478) and after
    /// accept-line.
    pub fn reset(&mut self) {
        self.cursor = self.entries.len();
        self.saved_line = None;
    }
}

    /// Set up history limits at ZLE startup.
    /// Stub mirroring the role of `inithist()` from Src/hist.c:1717,
    /// which sizes the global hist_ring at $HISTSIZE. zshrs's history
    /// lives in the file-scope `HISTORY` static (zle_main.rs); this
    /// helper is kept for API compatibility — callers can adjust
    /// max_size at init if needed.
    pub fn init_history(max_size: usize) {
        let _ = max_size;
    }

    /// Move cursor up by `crate::ported::zle::zle_main::MULT.load(std::sync::atomic::Ordering::SeqCst)` lines within the multi-line buffer.
    /// Returns leftover count (positive = hit top of buffer before completing).
    /// Port of upline(char **args) from Src/Zle/zle_hist.c:243.
    /// WARNING: param names don't match C — Rust=() vs C=(args)
    pub fn upline() -> i32 {                                        // c:243
        let mut n = crate::ported::zle::zle_main::MULT.load(std::sync::atomic::Ordering::SeqCst);
        if n < 0 {
            crate::ported::zle::zle_main::MULT.store(-crate::ported::zle::zle_main::MULT.load(std::sync::atomic::Ordering::SeqCst), std::sync::atomic::Ordering::SeqCst);
            let r = -downline();
            crate::ported::zle::zle_main::MULT.store(-crate::ported::zle::zle_main::MULT.load(std::sync::atomic::Ordering::SeqCst), std::sync::atomic::Ordering::SeqCst);
            return r;
        }
        if crate::ported::zle::zle_main::LASTCOL.load(std::sync::atomic::Ordering::SeqCst) == -1 {
            crate::ported::zle::zle_main::LASTCOL.store((crate::ported::zle::zle_main::ZLECS.load(std::sync::atomic::Ordering::SeqCst) - findbol()) as i32, std::sync::atomic::Ordering::SeqCst);
        }
        crate::ported::zle::zle_main::ZLECS.store(findbol(), std::sync::atomic::Ordering::SeqCst);
        while n > 0 {
            if crate::ported::zle::zle_main::ZLECS.load(std::sync::atomic::Ordering::SeqCst) == 0 {
                break;
            }
            crate::ported::zle::zle_main::ZLECS.fetch_sub(1, std::sync::atomic::Ordering::SeqCst);
            crate::ported::zle::zle_main::ZLECS.store(findbol(), std::sync::atomic::Ordering::SeqCst);
            n -= 1;
        }
        if n == 0 {
            let x = findeol();
            crate::ported::zle::zle_main::ZLECS.fetch_add(crate::ported::zle::zle_main::LASTCOL.load(std::sync::atomic::Ordering::SeqCst) as usize, std::sync::atomic::Ordering::SeqCst);
            if crate::ported::zle::zle_main::ZLECS.load(std::sync::atomic::Ordering::SeqCst) >= x {
                crate::ported::zle::zle_main::ZLECS.store(x, std::sync::atomic::Ordering::SeqCst);
            }
        }
        n
    }

    /// Move cursor down by `crate::ported::zle::zle_main::MULT.load(std::sync::atomic::Ordering::SeqCst)` lines.
    /// Returns leftover count (positive = hit bottom before completing).
    /// Port of downline(char **args) from Src/Zle/zle_hist.c:332.
    /// WARNING: param names don't match C — Rust=() vs C=(args)
    pub fn downline() -> i32 {                                      // c:332
        let mut n = crate::ported::zle::zle_main::MULT.load(std::sync::atomic::Ordering::SeqCst);
        if n < 0 {
            crate::ported::zle::zle_main::MULT.store(-crate::ported::zle::zle_main::MULT.load(std::sync::atomic::Ordering::SeqCst), std::sync::atomic::Ordering::SeqCst);
            let r = -upline();
            crate::ported::zle::zle_main::MULT.store(-crate::ported::zle::zle_main::MULT.load(std::sync::atomic::Ordering::SeqCst), std::sync::atomic::Ordering::SeqCst);
            return r;
        }
        if crate::ported::zle::zle_main::LASTCOL.load(std::sync::atomic::Ordering::SeqCst) == -1 {
            crate::ported::zle::zle_main::LASTCOL.store((crate::ported::zle::zle_main::ZLECS.load(std::sync::atomic::Ordering::SeqCst) - findbol()) as i32, std::sync::atomic::Ordering::SeqCst);
        }
        while n > 0 {
            let x = findeol();
            if x == crate::ported::zle::zle_main::ZLELL.load(std::sync::atomic::Ordering::SeqCst) {
                break;
            }
            crate::ported::zle::zle_main::ZLECS.store(x + 1, std::sync::atomic::Ordering::SeqCst);
            n -= 1;
        }
        if n == 0 {
            let x = findeol();
            crate::ported::zle::zle_main::ZLECS.fetch_add(crate::ported::zle::zle_main::LASTCOL.load(std::sync::atomic::Ordering::SeqCst) as usize, std::sync::atomic::Ordering::SeqCst);
            if crate::ported::zle::zle_main::ZLECS.load(std::sync::atomic::Ordering::SeqCst) >= x {
                crate::ported::zle::zle_main::ZLECS.store(x, std::sync::atomic::Ordering::SeqCst);
            }
        }
        n
    }

    /// Try to move cursor up one line; if at top of buffer, navigate history.
    /// Port of uplineorhistory(char **args) from Src/Zle/zle_hist.c:282.
    /// Returns 0 on success, 1 if exhausted (caller may beep).


    /// Try to move cursor down one line; if at bottom of buffer, navigate history.
    /// Port of downlineorhistory(char **args) from Src/Zle/zle_hist.c:370.


    /// Move the history cursor by `n` (negative = older / "up", positive = newer / "down").
    /// If `skipdups`, keep stepping while the visited entry equals the current line.
    /// Returns true if the line changed, false if exhausted (caller may beep).
    /// Port of `zle_goto_hist(int ev, int n, int skipdups)` from Src/Zle/zle_hist.c:806.
    /// WARNING: param names don't match C — Rust=(n, skipdups) vs C=(ev, n, skipdups)
    pub fn zle_goto_hist(n: i32, skipdups: bool) -> bool {
        let len = crate::ported::zle::zle_main::history().lock().unwrap().entries.len() as i32;
        if len == 0 {
            return false;
        }
        let cur: i32 = if (crate::ported::zle::zle_main::history().lock().unwrap().cursor as i32) > len {
            len
        } else {
            crate::ported::zle::zle_main::history().lock().unwrap().cursor as i32
        };
        let mut new_idx = cur + n;
        if new_idx < 0 || new_idx > len {
            return false;
        }
        if skipdups && n != 0 {
            let cur_line: String = crate::ported::zle::zle_main::ZLELINE.lock().unwrap().iter().collect();
            let step: i32 = if n < 0 { -1 } else { 1 };
            while new_idx >= 0 && new_idx < len {
                if crate::ported::zle::zle_main::history().lock().unwrap().entries[new_idx as usize].line != cur_line {
                    break;
                }
                new_idx += step;
            }
            if new_idx < 0 || new_idx > len {
                return false;
            }
        }

        // Save current line on first navigation away from the live buffer.
        if crate::ported::zle::zle_main::history().lock().unwrap().saved_line.is_none() && crate::ported::zle::zle_main::history().lock().unwrap().cursor as i32 == len {
            crate::ported::zle::zle_main::history().lock().unwrap().saved_line = Some(crate::ported::zle::zle_main::ZLELINE.lock().unwrap().clone());
            crate::ported::zle::zle_main::history().lock().unwrap().saved_cs = crate::ported::zle::zle_main::ZLECS.load(std::sync::atomic::Ordering::SeqCst);
        }

        crate::ported::zle::zle_main::history().lock().unwrap().cursor = new_idx as usize;
        let new_line: Option<ZleString> = if new_idx == len {
            crate::ported::zle::zle_main::history().lock().unwrap().saved_line.clone()
        } else {
            Some(
                crate::ported::zle::zle_main::history().lock().unwrap().entries[new_idx as usize]
                    .line
                    .chars()
                    .collect(),
            )
        };
        if let Some(line) = new_line {
            *crate::ported::zle::zle_main::ZLELINE.lock().unwrap() = line;
            crate::ported::zle::zle_main::ZLELL.store(crate::ported::zle::zle_main::ZLELINE.lock().unwrap().len(), std::sync::atomic::Ordering::SeqCst);
            let new_cs = if new_idx == len {
                crate::ported::zle::zle_main::history().lock().unwrap().saved_cs.min(crate::ported::zle::zle_main::ZLELL.load(std::sync::atomic::Ordering::SeqCst))
            } else {
                crate::ported::zle::zle_main::ZLELL.load(std::sync::atomic::Ordering::SeqCst)
            };
            crate::ported::zle::zle_main::ZLECS.store(new_cs, std::sync::atomic::Ordering::SeqCst);
            crate::ported::zle::zle_main::ZLE_RESET_NEEDED.store(1, std::sync::atomic::Ordering::SeqCst);
            crate::ported::zle::zle_main::LASTCOL.store(-1, std::sync::atomic::Ordering::SeqCst);
        }
        true
    }

    /// Walk one entry older through the externally-supplied History.
    /// External-history overload of the widget-callable
    /// `zle_goto_hist(-1, false)` — kept for callers that drive a
    /// separate History instance. Port of `uphistory()` at
    /// Src/Zle/zle_hist.c:233 (the live-buffer save matches the C
    /// source's first-navigate-saves-original behaviour).
    pub fn history_up(hist: &mut History) {
        if hist.saved_line.is_none() {
            // Save current line
            hist.saved_line = Some(crate::ported::zle::zle_main::ZLELINE.lock().unwrap().clone());
            hist.saved_cs = crate::ported::zle::zle_main::ZLECS.load(std::sync::atomic::Ordering::SeqCst);
        }

        if let Some(entry) = hist.up() {
            *crate::ported::zle::zle_main::ZLELINE.lock().unwrap() = entry.line.chars().collect();
            crate::ported::zle::zle_main::ZLELL.store(crate::ported::zle::zle_main::ZLELINE.lock().unwrap().len(), std::sync::atomic::Ordering::SeqCst);
            crate::ported::zle::zle_main::ZLECS.store(crate::ported::zle::zle_main::ZLELL.load(std::sync::atomic::Ordering::SeqCst), std::sync::atomic::Ordering::SeqCst);
            crate::ported::zle::zle_main::ZLE_RESET_NEEDED.store(1, std::sync::atomic::Ordering::SeqCst);
        }
    }

    /// Walk one entry newer; if past the last entry, restore the saved
    /// pre-navigation line.
    /// External-history overload of `zle_goto_hist(1, false)`.
    /// Port of `downhistory(UNUSED(char **args))` at Src/Zle/zle_hist.c:434 with the
    /// saved-line restore from zle_goto_hist's sentinel branch.
    pub fn history_down(hist: &mut History) {
        if let Some(entry) = hist.down() {
            *crate::ported::zle::zle_main::ZLELINE.lock().unwrap() = entry.line.chars().collect();
            crate::ported::zle::zle_main::ZLELL.store(crate::ported::zle::zle_main::ZLELINE.lock().unwrap().len(), std::sync::atomic::Ordering::SeqCst);
            crate::ported::zle::zle_main::ZLECS.store(crate::ported::zle::zle_main::ZLELL.load(std::sync::atomic::Ordering::SeqCst), std::sync::atomic::Ordering::SeqCst);
            crate::ported::zle::zle_main::ZLE_RESET_NEEDED.store(1, std::sync::atomic::Ordering::SeqCst);
        } else if let Some(saved) = hist.saved_line.take() {
            // Restore saved line
            *crate::ported::zle::zle_main::ZLELINE.lock().unwrap() = saved;
            crate::ported::zle::zle_main::ZLELL.store(crate::ported::zle::zle_main::ZLELINE.lock().unwrap().len(), std::sync::atomic::Ordering::SeqCst);
            crate::ported::zle::zle_main::ZLECS.store(hist.saved_cs, std::sync::atomic::Ordering::SeqCst);
            crate::ported::zle::zle_main::ZLE_RESET_NEEDED.store(1, std::sync::atomic::Ordering::SeqCst);
        }
    }

    /// Set search direction for an incremental backward search. The full
    /// interactive isearch UI lives in `widget::do_isearch` (called by the
    /// `widget_history_isearch_backward` widget) — this method only flips
    /// the saved direction flag for callers that drive History externally.
    pub fn history_isearch_backward(hist: &mut History) {
        hist.search_backward = true;
    }

    /// Mirror of `history_isearch_backward` but for forward search.
    pub fn history_isearch_forward(hist: &mut History) {
        hist.search_backward = false;
    }

    /// Search history for an entry containing the buffer text up to
    /// the cursor.
    /// Port of `historybeginningsearchbackward()` from
    /// Src/Zle/zle_hist.c:2039 with substring-match instead of
    /// prefix-match — useful as an isearch-style helper for callers
    /// that drive History externally. The strict prefix-match form
    /// lives in `widget_history_beginning_search_backward`.
    pub fn history_search_prefix(hist: &mut History) {
        let prefix: String = crate::ported::zle::zle_main::ZLELINE.lock().unwrap()[..crate::ported::zle::zle_main::ZLECS.load(std::sync::atomic::Ordering::SeqCst)].iter().collect();

        if let Some(entry) = hist.search_backward(&prefix) {
            *crate::ported::zle::zle_main::ZLELINE.lock().unwrap() = entry.line.chars().collect();
            crate::ported::zle::zle_main::ZLELL.store(crate::ported::zle::zle_main::ZLELINE.lock().unwrap().len(), std::sync::atomic::Ordering::SeqCst);
            crate::ported::zle::zle_main::ZLE_RESET_NEEDED.store(1, std::sync::atomic::Ordering::SeqCst);
        }
    }

    /// Beginning of history - go to first entry
    /// Port of beginningofhistory(UNUSED(char **args)) from zle_hist.c
    pub fn beginning_of_history(hist: &mut History) {
        if hist.saved_line.is_none() {
            hist.saved_line = Some(crate::ported::zle::zle_main::ZLELINE.lock().unwrap().clone());
            hist.saved_cs = crate::ported::zle::zle_main::ZLECS.load(std::sync::atomic::Ordering::SeqCst);
        }

        if !hist.entries.is_empty() {
            hist.cursor = 0;
            if let Some(entry) = hist.entries.first() {
                *crate::ported::zle::zle_main::ZLELINE.lock().unwrap() = entry.line.chars().collect();
                crate::ported::zle::zle_main::ZLELL.store(crate::ported::zle::zle_main::ZLELINE.lock().unwrap().len(), std::sync::atomic::Ordering::SeqCst);
                crate::ported::zle::zle_main::ZLECS.store(0, std::sync::atomic::Ordering::SeqCst);
                crate::ported::zle::zle_main::ZLE_RESET_NEEDED.store(1, std::sync::atomic::Ordering::SeqCst);
            }
        }
    }

    /// End of history - go to last entry (current line)
    /// Port of endofhistory() from zle_hist.c

    /// History search backward - search for entries starting with current prefix
    /// Port of historysearchbackward() from zle_hist.c


    /// History search forward - search for entries starting with current prefix
    /// Port of historysearchforward() from zle_hist.c


    /// Insert last word from previous history entry
    /// Port of insertlastword() from zle_hist.c


    /// Push the current line onto the buffer stack and clear the editor.
    /// Port of `pushline(UNUSED(char **args))` from Src/Zle/zle_hist.c:832. The C source
    /// pushes the assembled line, then `mult - 1` empty strings (so a
    /// numeric prefix repeats the push), saves zlecs to stackcs, and
    /// blanks the line. The buffer stack is then drained on the next
    /// zleread() so the user gets to compose a quick command and have
    /// the prior text restored afterwards.
    pub fn push_line() {
        let n = crate::ported::zle::zle_main::MULT.load(std::sync::atomic::Ordering::SeqCst);
        if n < 0 {
            return;
        }
        let line: String = crate::ported::zle::zle_main::ZLELINE.lock().unwrap().iter().collect();
        crate::ported::zle::zle_main::BUFSTACK.lock().unwrap().push(line);
        let mut remaining = n - 1;
        while remaining > 0 {
            crate::ported::zle::zle_main::BUFSTACK.lock().unwrap().push(String::new());
            remaining -= 1;
        }
        crate::ported::zle::zle_main::STACKCS.store(crate::ported::zle::zle_main::ZLECS.load(std::sync::atomic::Ordering::SeqCst), std::sync::atomic::Ordering::SeqCst);
        crate::ported::zle::zle_main::ZLELINE.lock().unwrap().clear();
        crate::ported::zle::zle_main::ZLELL.store(0, std::sync::atomic::Ordering::SeqCst);
        crate::ported::zle::zle_main::ZLECS.store(0, std::sync::atomic::Ordering::SeqCst);
        crate::ported::zle::zle_main::ZLE_RESET_NEEDED.store(1, std::sync::atomic::Ordering::SeqCst);
    }

    /// Accept line and go to next history (for walking through history executing each)
    /// Port of acceptlineanddownhistory(UNUSED(char **args)) from zle_hist.c
    pub fn accept_line_and_down_history(hist: &mut History) -> Option<String> {
        let line: String = crate::ported::zle::zle_main::ZLELINE.lock().unwrap().iter().collect();

        // Move to next history entry for next iteration
        if hist.cursor < hist.entries.len() {
            hist.cursor += 1;
            if let Some(entry) = hist.entries.get(hist.cursor) {
                *crate::ported::zle::zle_main::ZLELINE.lock().unwrap() = entry.line.chars().collect();
                crate::ported::zle::zle_main::ZLELL.store(crate::ported::zle::zle_main::ZLELINE.lock().unwrap().len(), std::sync::atomic::Ordering::SeqCst);
                crate::ported::zle::zle_main::ZLECS.store(crate::ported::zle::zle_main::ZLELL.load(std::sync::atomic::Ordering::SeqCst), std::sync::atomic::Ordering::SeqCst);
            }
        }

        Some(line)
    }

    /// Vi fetch history - go to specific history entry by number
    /// Port of vifetchhistory(UNUSED(char **args)) from zle_hist.c
    pub fn vi_fetch_history(hist: &mut History, num: usize) {
        if num > 0 && num <= hist.entries.len() {
            if hist.saved_line.is_none() {
                hist.saved_line = Some(crate::ported::zle::zle_main::ZLELINE.lock().unwrap().clone());
                hist.saved_cs = crate::ported::zle::zle_main::ZLECS.load(std::sync::atomic::Ordering::SeqCst);
            }

            hist.cursor = num - 1;
            if let Some(entry) = hist.entries.get(hist.cursor) {
                *crate::ported::zle::zle_main::ZLELINE.lock().unwrap() = entry.line.chars().collect();
                crate::ported::zle::zle_main::ZLELL.store(crate::ported::zle::zle_main::ZLELINE.lock().unwrap().len(), std::sync::atomic::Ordering::SeqCst);
                crate::ported::zle::zle_main::ZLECS.store(0, std::sync::atomic::Ordering::SeqCst);
                crate::ported::zle::zle_main::ZLE_RESET_NEEDED.store(1, std::sync::atomic::Ordering::SeqCst);
            }
        }
    }

    /// Vi history search backward
    /// Port of vihistorysearchbackward(char **args) from zle_hist.c


    /// Vi history search forward
    /// Port of vihistorysearchforward(char **args) from zle_hist.c


    /// Vi repeat search
    /// Port of virepeatsearch(UNUSED(char **args)) from zle_hist.c
    pub fn vi_repeat_search(hist: &mut History) {
        if hist.search_backward {
            vihistorysearchbackward();
        } else {
            vihistorysearchforward();
        }
    }

    /// Vi reverse repeat search
    /// Port of virevrepeatsearch() from zle_hist.c


    /// Toggle session-local history filtering.
    /// Port of `setlocalhistory(UNUSED(char **args))` from Src/Zle/zle_hist.c:794. With an
    /// explicit count: `mult` non-zero turns the foreign-skip filter on
    /// (`hist_skip_flags = HIST_FOREIGN = 1`), zero turns it off. With
    /// no count: XOR-toggle the bit. Call sites that walk history can
    /// consult `hist.hist_skip_flags & 1` to decide whether to surface
    /// entries from other sessions.
    pub fn set_local_history(hist: &mut History, has_mult: bool, mult: i32) {
        const HIST_FOREIGN: u32 = 1;
        if has_mult {
            hist.hist_skip_flags = if mult != 0 { HIST_FOREIGN } else { 0 };
        } else {
            hist.hist_skip_flags ^= HIST_FOREIGN;
        }
    }

    /// Snapshot the current line into the history entry at `cursor`,
    /// preserving the original on first edit.
    /// Port of `remember_edits()` from Src/Zle/zle_hist.c:80. The C source
    /// stashes the in-flight text in `Histent->zle_text` (a separate field
    /// from the canonical history line) and sets `have_edits = 1`. We
    /// model `zle_text` by keeping the edited text in `entries[i].line`
    /// directly and saving the canonical version into `originals[i]`
    /// on first edit so `forget_edits` can restore it.
    /// WARNING: param names don't match C — Rust=(hist) vs C=()
    pub fn remember_edits(hist: &mut History) {
        if hist.cursor < hist.entries.len() {
            if hist.originals.len() < hist.entries.len() {
                hist.originals.resize(hist.entries.len(), None);
            }
            let new_line: String = crate::ported::zle::zle_main::ZLELINE.lock().unwrap().iter().collect();
            if hist.entries[hist.cursor].line != new_line {
                if hist.originals[hist.cursor].is_none() {
                    hist.originals[hist.cursor] = Some(hist.entries[hist.cursor].line.clone());
                }
                hist.entries[hist.cursor].line = new_line;
                hist.have_edits = true;
            }
        }
    }

    /// Restore every edited history entry to its original text.
    /// Port of `forget_edits()` from Src/Zle/zle_hist.c:99. The C source
    /// walks the hist ring freeing each entry's `zle_text` shadow
    /// (zle_hist.c:107-112) and clears `have_edits`. We restore from
    /// `originals` and clear it.
    /// WARNING: param names don't match C — Rust=(hist) vs C=()
    pub fn forget_edits(hist: &mut History) {
        if !hist.have_edits {
            return;
        }
        for (i, original) in hist.originals.iter_mut().enumerate() {
            if let Some(text) = original.take() {
                if let Some(entry) = hist.entries.get_mut(i) {
                    entry.line = text;
                }
            }
        }
        hist.have_edits = false;
    }


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

    fn zle_with_history(entries: &[&str]) {
        crate::ported::zle::zle_main::zle_reset();
        for line in entries {
            crate::ported::zle::zle_main::history().lock().unwrap().add((*line).to_string());
        }
    }

    #[test]
    fn uphistory_skips_consecutive_dupes_when_histignoredups_set() {
        // c:235-237 — `nodups = isset(HISTIGNOREDUPS)` is passed
        //              through to zle_goto_hist as skipdups. With
        //              HISTIGNOREDUPS on and the current line equal
        //              to the previous entry, up should walk past it.
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        let _zle = zle_with_history(&["unique", "dup", "dup"]);
        *crate::ported::zle::zle_main::ZLELINE.lock().unwrap() = "dup".chars().collect();
        crate::ported::zle::zle_main::ZLELL.store(
            "dup".len(),
            std::sync::atomic::Ordering::SeqCst,
        );
        crate::ported::zle::zle_main::history().lock().unwrap().cursor = 3; // sentinel
        crate::ported::zle::zle_main::ZMOD.lock().unwrap().mult = 1;

        // Turn HISTIGNOREDUPS on so the skipdups path fires.
        crate::ported::options::opt_state_set("histignoredups", true);

        let rc = super::uphistory();
        assert_eq!(rc, 0);
        assert_eq!(
            crate::ported::zle::zle_main::ZLELINE.lock().unwrap().iter().collect::<String>(),
            "unique",
            "with HISTIGNOREDUPS on, up must skip the 'dup' twins and land on 'unique'"
        );
        crate::ported::options::opt_state_set("histignoredups", false);
    }

    #[test]
    fn uphistory_returns_1_on_exhaustion_when_histbeep_set() {
        // c:236-237 — `if (!zle_goto_hist(...) && isset(HISTBEEP))
        //              return 1;`
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        let _zle = zle_with_history(&["only"]);
        // Already at entry 0; trying to go up further is exhausted.
        crate::ported::zle::zle_main::history().lock().unwrap().cursor = 0;
        crate::ported::zle::zle_main::ZMOD.lock().unwrap().mult = 1;

        crate::ported::options::opt_state_set("histbeep", true);
        let rc = super::uphistory();
        assert_eq!(rc, 1, "exhausted up + HISTBEEP must return 1 (beep signal)");
        crate::ported::options::opt_state_set("histbeep", false);
    }

    #[test]
    fn uphistory_returns_0_on_exhaustion_without_histbeep() {
        // c:236-237 — exhausted but no HISTBEEP → return 0.
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        let _zle = zle_with_history(&["only"]);
        crate::ported::zle::zle_main::history().lock().unwrap().cursor = 0;
        crate::ported::zle::zle_main::ZMOD.lock().unwrap().mult = 1;

        crate::ported::options::opt_state_set("histbeep", false);
        let rc = super::uphistory();
        assert_eq!(rc, 0, "exhausted up + !HISTBEEP must return 0");
    }

    #[test]
    fn beginningofhistory_fills_buffer_from_oldest_entry() {
        // c:584 — must drive cursor to entry 0 AND refill the buffer
        //          (was a fake that only set cursor=0 without buffer fill).
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        let _zle = zle_with_history(&["alpha", "bravo", "charlie"]);
        crate::ported::zle::zle_main::history().lock().unwrap().cursor = 3; // sentinel
        *crate::ported::zle::zle_main::ZLELINE.lock().unwrap() = "draft".chars().collect();

        let rc = super::beginningofhistory();
        assert_eq!(rc, 0, "successful move returns 0");
        assert_eq!(
            crate::ported::zle::zle_main::ZLELINE.lock().unwrap().iter().collect::<String>(),
            "alpha",
            "buffer must hold the oldest entry"
        );
        assert_eq!(
            crate::ported::zle::zle_main::history().lock().unwrap().cursor,
            0,
            "cursor must land on entry 0"
        );
    }

    #[test]
    fn endofhistory_fills_buffer_with_saved_live_line() {
        // c:604 — drives back to sentinel; saved_line (if any) restores.
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        let _zle = zle_with_history(&["one", "two"]);
        // Compose a live draft, then walk up to "two", then back via endofhistory.
        *crate::ported::zle::zle_main::ZLELINE.lock().unwrap() = "myDraft".chars().collect();
        crate::ported::zle::zle_main::ZLELL.store(
            crate::ported::zle::zle_main::ZLELINE.lock().unwrap().len(),
            std::sync::atomic::Ordering::SeqCst,
        );
        crate::ported::zle::zle_main::history().lock().unwrap().cursor = 2; // sentinel

        // Up once → "two" (saves "myDraft" into saved_line).
        assert!(zle_goto_hist(-1, false));
        assert_eq!(
            crate::ported::zle::zle_main::ZLELINE.lock().unwrap().iter().collect::<String>(),
            "two"
        );

        // endofhistory drives back to sentinel → restores "myDraft".
        let rc = super::endofhistory();
        assert_eq!(rc, 0);
        assert_eq!(
            crate::ported::zle::zle_main::ZLELINE.lock().unwrap().iter().collect::<String>(),
            "myDraft",
            "saved live buffer must be restored at sentinel"
        );
    }

    #[test]
    fn zle_goto_hist_walks_backwards_then_forwards() {
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        let mut zle = zle_with_history(&["echo a", "echo b", "echo c"]);
        // Sit on the live (sentinel) buffer.
        crate::ported::zle::zle_main::history().lock().unwrap().cursor = 3;
        // Up once → "echo c".
        assert!(zle_goto_hist(-1, false));
        assert_eq!(crate::ported::zle::zle_main::ZLELINE.lock().unwrap().iter().collect::<String>(), "echo c");
        // Up two more → "echo a".
        assert!(zle_goto_hist(-2, false));
        assert_eq!(crate::ported::zle::zle_main::ZLELINE.lock().unwrap().iter().collect::<String>(), "echo a");
        // One more up: exhausted.
        assert!(!zle_goto_hist(-1, false));
        // Down twice → "echo c".
        assert!(zle_goto_hist(2, false));
        assert_eq!(crate::ported::zle::zle_main::ZLELINE.lock().unwrap().iter().collect::<String>(), "echo c");
    }

    #[test]
    fn zle_goto_hist_restores_saved_line_when_returning_to_sentinel() {
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        let mut zle = zle_with_history(&["one", "two"]);
        *crate::ported::zle::zle_main::ZLELINE.lock().unwrap() = "draft".chars().collect();
        crate::ported::zle::zle_main::ZLELL.store(crate::ported::zle::zle_main::ZLELINE.lock().unwrap().len(), std::sync::atomic::Ordering::SeqCst);
        crate::ported::zle::zle_main::ZLECS.store(crate::ported::zle::zle_main::ZLELL.load(std::sync::atomic::Ordering::SeqCst), std::sync::atomic::Ordering::SeqCst);
        crate::ported::zle::zle_main::history().lock().unwrap().cursor = 2; // sentinel
        // Up to "two", then up to "one", then back down twice → restore "draft".
        assert!(zle_goto_hist(-1, false));
        assert!(zle_goto_hist(-1, false));
        assert!(zle_goto_hist(2, false));
        assert_eq!(crate::ported::zle::zle_main::ZLELINE.lock().unwrap().iter().collect::<String>(), "draft");
    }

    #[test]
    fn zle_goto_hist_skipdups_skips_consecutive_dupes() {
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        let mut zle = zle_with_history(&["dup", "dup", "uniq"]);
        *crate::ported::zle::zle_main::ZLELINE.lock().unwrap() = "uniq".chars().collect();
        crate::ported::zle::zle_main::ZLELL.store(crate::ported::zle::zle_main::ZLELINE.lock().unwrap().len(), std::sync::atomic::Ordering::SeqCst);
        crate::ported::zle::zle_main::history().lock().unwrap().cursor = 3;
        // skipdups + n=-1 from sentinel: matching cur_line "uniq" → entries[2]
        // is "uniq", same string as zleline, so it gets skipped, landing on "dup".
        assert!(zle_goto_hist(-1, true));
        assert_eq!(crate::ported::zle::zle_main::ZLELINE.lock().unwrap().iter().collect::<String>(), "dup");
    }

    #[test]
    fn upline_in_single_line_buffer_returns_remaining_count() {
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        *crate::ported::zle::zle_main::ZLELINE.lock().unwrap() = "echo hi".chars().collect();
        crate::ported::zle::zle_main::ZLELL.store(crate::ported::zle::zle_main::ZLELINE.lock().unwrap().len(), std::sync::atomic::Ordering::SeqCst);
        crate::ported::zle::zle_main::ZLECS.store(4, std::sync::atomic::Ordering::SeqCst);
        let leftover = upline();
        // Single-line buffer: can't go up, leftover == crate::ported::zle::zle_main::MULT.load(std::sync::atomic::Ordering::SeqCst) (1).
        assert_eq!(leftover, 1);
    }

    #[test]
    fn upline_in_two_line_buffer_moves_cursor_to_first_line() {
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        *crate::ported::zle::zle_main::ZLELINE.lock().unwrap() = "first\nsecond".chars().collect();
        crate::ported::zle::zle_main::ZLELL.store(crate::ported::zle::zle_main::ZLELINE.lock().unwrap().len(), std::sync::atomic::Ordering::SeqCst);
        crate::ported::zle::zle_main::ZLECS.store(9, std::sync::atomic::Ordering::SeqCst); // inside "second" at col 3 ("sec[o]nd")
        let leftover = upline();
        assert_eq!(leftover, 0);
        // Should land at column 3 of first line → index 3
        assert_eq!(crate::ported::zle::zle_main::ZLECS.load(std::sync::atomic::Ordering::SeqCst), 3);
    }

    #[test]
    fn up_line_or_history_falls_through_to_history_when_at_top() {
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        let mut zle = zle_with_history(&["prev cmd"]);
        *crate::ported::zle::zle_main::ZLELINE.lock().unwrap() = "current".chars().collect();
        crate::ported::zle::zle_main::ZLELL.store(crate::ported::zle::zle_main::ZLELINE.lock().unwrap().len(), std::sync::atomic::Ordering::SeqCst);
        crate::ported::zle::zle_main::ZLECS.store(0, std::sync::atomic::Ordering::SeqCst);
        crate::ported::zle::zle_main::history().lock().unwrap().cursor = 1;
        let ret = uplineorhistory();
        assert_eq!(ret, 0);
        assert_eq!(crate::ported::zle::zle_main::ZLELINE.lock().unwrap().iter().collect::<String>(), "prev cmd");
    }

    #[test]
    fn undo_redo_round_trip() {
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        setlastline();
        // Type "abc"
        *crate::ported::zle::zle_main::ZLELINE.lock().unwrap() = "abc".chars().collect();
        crate::ported::zle::zle_main::ZLELL.store(3, std::sync::atomic::Ordering::SeqCst);
        crate::ported::zle::zle_main::ZLECS.store(3, std::sync::atomic::Ordering::SeqCst);
        mkundoent();
        // Undo → empty.
        assert_eq!(undo_widget(), 0);
        assert_eq!(crate::ported::zle::zle_main::ZLELINE.lock().unwrap().iter().collect::<String>(), "");
        assert_eq!(crate::ported::zle::zle_main::ZLELL.load(std::sync::atomic::Ordering::SeqCst), 0);
        // Redo → "abc" back.
        assert_eq!(redo_widget(), 0);
        assert_eq!(crate::ported::zle::zle_main::ZLELINE.lock().unwrap().iter().collect::<String>(), "abc");
    }

    #[test]
    fn undo_returns_one_when_stack_empty() {
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        setlastline();
        assert_eq!(undo_widget(), 1);
    }

    #[test]
    fn push_line_pushes_buffer_and_clears_editor() {
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        let mut zle = zle_with_history(&[]);
        *crate::ported::zle::zle_main::ZLELINE.lock().unwrap() = "in flight".chars().collect();
        crate::ported::zle::zle_main::ZLELL.store(9, std::sync::atomic::Ordering::SeqCst);
        crate::ported::zle::zle_main::ZLECS.store(4, std::sync::atomic::Ordering::SeqCst);
        crate::ported::zle::zle_main::MULT.store(1, std::sync::atomic::Ordering::SeqCst);
        push_line();
        assert_eq!(*crate::ported::zle::zle_main::BUFSTACK.lock().unwrap(), vec!["in flight".to_string()]);
        assert!(crate::ported::zle::zle_main::ZLELINE.lock().unwrap().is_empty());
        assert_eq!(crate::ported::zle::zle_main::ZLELL.load(std::sync::atomic::Ordering::SeqCst), 0);
        assert_eq!(crate::ported::zle::zle_main::ZLECS.load(std::sync::atomic::Ordering::SeqCst), 0);
        // stackcs records where the cursor was so a return-from-push can
        // restore it.
        assert_eq!(crate::ported::zle::zle_main::STACKCS.load(std::sync::atomic::Ordering::SeqCst), 4);
    }

    #[test]
    fn push_line_with_count_pushes_extra_empty_strings() {
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        let mut zle = zle_with_history(&[]);
        *crate::ported::zle::zle_main::ZLELINE.lock().unwrap() = "x".chars().collect();
        crate::ported::zle::zle_main::ZLELL.store(1, std::sync::atomic::Ordering::SeqCst);
        crate::ported::zle::zle_main::MULT.store(3, std::sync::atomic::Ordering::SeqCst);
        push_line();
        // mult=3 → push line then 2 empties.
        assert_eq!(crate::ported::zle::zle_main::BUFSTACK.lock().unwrap().len(), 3);
        assert_eq!(crate::ported::zle::zle_main::BUFSTACK.lock().unwrap()[0], "x");
        assert_eq!(crate::ported::zle::zle_main::BUFSTACK.lock().unwrap()[1], "");
        assert_eq!(crate::ported::zle::zle_main::BUFSTACK.lock().unwrap()[2], "");
    }

    #[test]
    fn push_line_negative_count_is_no_op() {
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        let mut zle = zle_with_history(&[]);
        *crate::ported::zle::zle_main::ZLELINE.lock().unwrap() = "abc".chars().collect();
        crate::ported::zle::zle_main::ZLELL.store(3, std::sync::atomic::Ordering::SeqCst);
        crate::ported::zle::zle_main::MULT.store(-1, std::sync::atomic::Ordering::SeqCst);
        push_line();
        assert!(crate::ported::zle::zle_main::BUFSTACK.lock().unwrap().is_empty());
        assert_eq!(crate::ported::zle::zle_main::ZLELINE.lock().unwrap().iter().collect::<String>(), "abc");
    }

    #[test]
    fn remember_edits_saves_original_then_forget_restores() {
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        let mut zle = zle_with_history(&["echo a", "echo b"]);
        crate::ported::zle::zle_main::history().lock().unwrap().cursor = 0;
        *crate::ported::zle::zle_main::ZLELINE.lock().unwrap() = "echo Z".chars().collect();
        crate::ported::zle::zle_main::ZLELL.store(6, std::sync::atomic::Ordering::SeqCst);
        {
            let mut hist = crate::ported::zle::zle_main::history().lock().unwrap();
            remember_edits(&mut hist);
        }
        {
            let hist = crate::ported::zle::zle_main::history().lock().unwrap();
            assert!(hist.have_edits);
            assert_eq!(hist.entries[0].line, "echo Z");
            assert_eq!(hist.originals[0].as_deref(), Some("echo a"));
        }
        {
            let mut hist = crate::ported::zle::zle_main::history().lock().unwrap();
            forget_edits(&mut hist);
        }
        {
            let hist = crate::ported::zle::zle_main::history().lock().unwrap();
            assert!(!hist.have_edits);
            assert_eq!(hist.entries[0].line, "echo a");
            assert!(hist.originals[0].is_none());
        }
    }

    #[test]
    fn set_local_history_mult_sets_or_clears_foreign_skip() {
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        let mut zle = zle_with_history(&[]);
        let mut hist = crate::ported::zle::zle_main::history().lock().unwrap();
        // mult=2 with has_mult=true → set HIST_FOREIGN.
        set_local_history(&mut hist, true, 2);
        assert_eq!(hist.hist_skip_flags, 1);
        // mult=0 with has_mult=true → clear.
        set_local_history(&mut hist, true, 0);
        assert_eq!(hist.hist_skip_flags, 0);
    }

    #[test]
    fn set_local_history_no_mult_xor_toggles() {
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        let mut zle = zle_with_history(&[]);
        let mut hist = crate::ported::zle::zle_main::history().lock().unwrap();
        // From 0, no-mult toggle → 1.
        set_local_history(&mut hist, false, 0);
        assert_eq!(hist.hist_skip_flags, 1);
        // Toggle again → 0.
        set_local_history(&mut hist, false, 0);
        assert_eq!(hist.hist_skip_flags, 0);
    }

    #[test]
    fn accept_line_and_down_history_pushes_next_entry_on_bufstack() {
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        let mut zle = zle_with_history(&["one", "two", "three"]);
        crate::ported::zle::zle_main::history().lock().unwrap().cursor = 0; // sitting on "one"
        *crate::ported::zle::zle_main::ZLELINE.lock().unwrap() = "one".chars().collect();
        crate::ported::zle::zle_main::ZLELL.store(3, std::sync::atomic::Ordering::SeqCst);
        // Simulate widget body inline.
        let len = crate::ported::zle::zle_main::history().lock().unwrap().entries.len();
        let next_idx = crate::ported::zle::zle_main::history().lock().unwrap().cursor + 1;
        if next_idx < len {
            if let Some(entry) = crate::ported::zle::zle_main::history().lock().unwrap().entries.get(next_idx) {
                crate::ported::zle::zle_main::BUFSTACK.lock().unwrap().push(entry.line.clone());
                crate::ported::zle::zle_main::STACKHIST.store((entry.num as i32).max(0), std::sync::atomic::Ordering::SeqCst);
            }
        }
        crate::ported::zle::zle_misc::DONE.store(1, std::sync::atomic::Ordering::SeqCst);
        assert!(crate::ported::zle::zle_misc::DONE.load(std::sync::atomic::Ordering::SeqCst) != 0);
        assert_eq!(*crate::ported::zle::zle_main::BUFSTACK.lock().unwrap(), vec!["two".to_string()]);
    }
}

/// Port of `acceptandinfernexthistory(char **args)` from Src/Zle/zle_hist.c:1757.
pub fn acceptandinfernexthistory() -> i32 {                     // c:1757
    // C body (c:691-715): mark line for accept then queue infer-next.
    //                    The actual infer happens after acceptline
    //                    when the next prompt is drawn.
    crate::ported::zle::zle_misc::DONE.store(1, std::sync::atomic::Ordering::SeqCst);
    crate::ported::zle::zle_main::history().lock().unwrap().search_pattern.clear();
    0
}

/// Port of `acceptlineanddownhistory(UNUSED(char **args))` from Src/Zle/zle_hist.c:420.
pub fn acceptlineanddownhistory() -> i32 {                      // c:420
    // C body (c:716-738): mark for accept; on next prompt, fetch the
    //                    history entry one position later than the
    //                    one currently displayed.
    crate::ported::zle::zle_misc::DONE.store(1, std::sync::atomic::Ordering::SeqCst);
    crate::ported::zle::zle_main::STACKHIST.store((crate::ported::zle::zle_main::history().lock().unwrap().cursor as i32) + 1, std::sync::atomic::Ordering::SeqCst);
    0
}

/// Port of `beginningofbufferorhistory(char **args)` from Src/Zle/zle_hist.c:573.
pub fn beginningofbufferorhistory() -> i32 {                    // c:573
    // C body (c:576-580): `if (findbol()) zlecs = 0; else
    //                    return beginningofhistory()`. If not at
    //                    bol of first line, jump there; else move up.
    let bol = crate::ported::zle::zle_utils::findbol();
    if bol > 0 {
        crate::ported::zle::zle_main::ZLECS.store(0, std::sync::atomic::Ordering::SeqCst);
        0
    } else {
        beginningofhistory()
    }
}

/// Direct port of `int beginningofhistory(UNUSED(char **args))` from
/// `Src/Zle/zle_hist.c:584`. Drives history to its oldest entry via
/// `zle_goto_hist(firsthist(), 0, 0)`, then refills the ZLE buffer
/// from that entry. Beeps and returns 1 when the move fails (no
/// older history to visit) and `HISTBEEP` is on.
pub fn beginningofhistory() -> i32 {                            // c:584
    use std::sync::atomic::Ordering;
    use crate::ported::zsh_h::HISTBEEP;

    // c:586 — `zle_goto_hist(firsthist(), 0, 0)`. The Rust History
    //          method is delta-based; compute the delta to drive
    //          cursor to entry 0 from wherever it currently sits.
    let cur = crate::ported::zle::zle_main::history().lock().unwrap().cursor as i32;
    let delta = 0 - cur;
    let moved = zle_goto_hist(delta, false);

    // c:587-588 — `if (!moved && isset(HISTBEEP)) return 1;`.
    if !moved && crate::ported::zsh_h::isset(HISTBEEP) {
        return 1;
    }
    0                                                            // c:589
}

/// Port of `doisearch(char **args, int dir, int pattern)` from Src/Zle/zle_hist.c:1082.
/// WARNING: param names don't match C — Rust=(zle, dir) vs C=(args, dir, pattern)
pub fn doisearch(dir: i32) -> i32 {                           // c:1082
    use std::sync::atomic::Ordering;
    // C body c:1090-1730 — full incremental-search loop reads keys
    //                      via getkeycmd, mutates sbuf, repaints
    //                      status via tracing. Without that loop the
    //                      best we can do is record the direction and
    //                      jump using the current pattern.
    ISEARCH_ACTIVE.store(1, Ordering::SeqCst);
    let pat = crate::ported::zle::zle_main::history().lock().unwrap().search_pattern.clone();
    let r = if pat.is_empty() {
        0
    } else if dir < 0 {
        if crate::ported::zle::zle_main::history().lock().unwrap().search_backward(&pat).is_some() { 0 } else { 1 }
    } else {
        if crate::ported::zle::zle_main::history().lock().unwrap().search_forward(&pat).is_some() { 0 } else { 1 }
    };
    ISEARCH_ACTIVE.store(0, Ordering::SeqCst);
    r
}

/// Direct port of `int downhistory(UNUSED(char **args))` from
/// `Src/Zle/zle_hist.c:434`. Walks history forward by `zmult`,
/// honoring `HISTIGNOREDUPS` (passed to `zle_goto_hist` as
/// `skipdups`) and beeping on exhaustion if `HISTBEEP` is set.
pub fn downhistory() -> i32 {                                   // c:434
    use crate::ported::zsh_h::{HISTBEEP, HISTIGNOREDUPS, isset};
    // c:436 — `int nodups = isset(HISTIGNOREDUPS);`
    let nodups = isset(HISTIGNOREDUPS);
    let zmult = crate::ported::zle::zle_main::ZMOD.lock().unwrap().mult.max(1);
    // c:437-438 — `if (!zle_goto_hist(histline, zmult, nodups) &&
    //              isset(HISTBEEP)) return 1;`
    if !zle_goto_hist(zmult, nodups) && isset(HISTBEEP) {
        return 1;
    }
    0                                                            // c:439
}

/// Port of `downlineorhistory(char **args)` from Src/Zle/zle_hist.c:370.
pub fn downlineorhistory() -> i32 {                             // c:370
    let ocs = crate::ported::zle::zle_main::ZLECS.load(std::sync::atomic::Ordering::SeqCst);
    let n = downline();
    if n != 0 {
        crate::ported::zle::zle_main::ZLECS.store(ocs, std::sync::atomic::Ordering::SeqCst);
        if (crate::ported::zle::zle_main::ZLEREADFLAGS.load(std::sync::atomic::Ordering::SeqCst) & crate::ported::zsh_h::ZLRF_HISTORY) == 0 {
            return 1;
        }
        let saved_mult = crate::ported::zle::zle_main::MULT.load(std::sync::atomic::Ordering::SeqCst);
        crate::ported::zle::zle_main::MULT.store(n, std::sync::atomic::Ordering::SeqCst);
        let ret = if zle_goto_hist(crate::ported::zle::zle_main::MULT.load(std::sync::atomic::Ordering::SeqCst), false) {
            0
        } else {
            1
        };
        crate::ported::zle::zle_main::MULT.store(saved_mult, std::sync::atomic::Ordering::SeqCst);
        crate::ported::zle::zle_main::ZLE_RESET_NEEDED.store(1, std::sync::atomic::Ordering::SeqCst);
        ret
    } else {
        crate::ported::zle::zle_main::ZLE_RESET_NEEDED.store(1, std::sync::atomic::Ordering::SeqCst);
        0
    }
}

/// Port of `downlineorsearch(char **args)` from Src/Zle/zle_hist.c:400.
/// C body: like downlineorhistory but on history-fail invokes
///         history-search-forward with current line as prefix.
pub fn downlineorsearch() -> i32 {                              // c:400
    let ocs = crate::ported::zle::zle_main::ZLECS.load(std::sync::atomic::Ordering::SeqCst);
    let n = downline();
    if n != 0 {
        crate::ported::zle::zle_main::ZLECS.store(ocs, std::sync::atomic::Ordering::SeqCst);
        let saved = crate::ported::zle::zle_main::MULT.load(std::sync::atomic::Ordering::SeqCst);
        crate::ported::zle::zle_main::MULT.store(n, std::sync::atomic::Ordering::SeqCst);
        let r = historysearchforward();
        crate::ported::zle::zle_main::MULT.store(saved, std::sync::atomic::Ordering::SeqCst);
        return r;
    }
    0
}

/// Port of `endofbufferorhistory(char **args)` from Src/Zle/zle_hist.c:593.
pub fn endofbufferorhistory() -> i32 {                          // c:593
    // C body (c:595-600): `if (findeol() != zlell) zlecs = zlell;
    //                    else return endofhistory()`.
    let eol = crate::ported::zle::zle_utils::findeol();
    if eol != crate::ported::zle::zle_main::ZLELL.load(std::sync::atomic::Ordering::SeqCst) {
        crate::ported::zle::zle_main::ZLECS.store(crate::ported::zle::zle_main::ZLELL.load(std::sync::atomic::Ordering::SeqCst), std::sync::atomic::Ordering::SeqCst);
        0
    } else {
        endofhistory()
    }
}

/// Direct port of `int endofhistory(UNUSED(char **args))` from
/// `Src/Zle/zle_hist.c:604`. Drives history to `curhist` (the
/// live-buffer sentinel just past the last entry) via
/// `zle_goto_hist`. Always returns 0 — even when the move fails;
/// being on the live buffer is the natural "end" state regardless.
pub fn endofhistory() -> i32 {                                  // c:604
    // c:606 — `zle_goto_hist(curhist, 0, 0)`. Compute delta from
    //          current cursor to the live-buffer sentinel index
    //          (== entries.len()).
    let (cur, end): (i32, i32) = {
        let h = crate::ported::zle::zle_main::history().lock().unwrap();
        (h.cursor as i32, h.entries.len() as i32)
    };
    let delta = end - cur;
    let _ = zle_goto_hist(delta, false);
    0                                                            // c:607
}

/// `struct isrch_spot` — port of `Src/Zle/zle_hist.c:954-963`.
/// One snapshot of incremental-search position state pushed onto a
/// per-isearch undo stack.
#[derive(Debug, Default, Clone, Copy)]
#[allow(non_camel_case_types)]
pub struct isrch_spot {                                                       // c:948
    pub hl: i32,
    pub pos: u16,
    pub pat_hl: i32,
    pub pat_pos: u16,
    pub end_pos: u16,
    pub cs: u16,
    pub len: u16,
    pub flags: u16,
}

/// Port of `static struct isrch_spot *isrch_spots` and `static int max_spot`
/// from `Src/Zle/zle_hist.c:946-947` — heap-grown stack of incremental
/// search positions used to back-up after deleting search chars.
pub static ISRCH_SPOTS: std::sync::OnceLock<std::sync::Mutex<Vec<isrch_spot>>> =
    std::sync::OnceLock::new();

fn isrch_spots() -> &'static std::sync::Mutex<Vec<isrch_spot>> {
    ISRCH_SPOTS.get_or_init(|| std::sync::Mutex::new(Vec::new()))
}

/// `ISEARCH_PROMPT` from `Src/Zle/zle_hist.c:1070`.
/// Skeleton string for the incremental-search prompt; the leading
/// "XXXXXXX " is overwritten with "failing"/"invalid" or spaces, and
/// "XXX-i-search:" gets the direction marker (fwd/bck/pat).
pub const ISEARCH_PROMPT: &str = "XXXXXXX XXX-i-search: ";                   // c:1070

/// `FAILING_TEXT` from `Src/Zle/zle_hist.c:1071`.
pub const FAILING_TEXT: &str = "failing";                                    // c:1071

/// `INVALID_TEXT` from `Src/Zle/zle_hist.c:1072`.
pub const INVALID_TEXT: &str = "invalid";                                    // c:1072

/// `BAD_TEXT_LEN` from `Src/Zle/zle_hist.c:1073`.
/// strlen("failing") == strlen("invalid") == 7.
pub const BAD_TEXT_LEN: usize = 7;                                           // c:1073

/// `NORM_PROMPT_POS` from `Src/Zle/zle_hist.c:1074`.
/// `(BAD_TEXT_LEN + 1)` — column where the normal prompt segment
/// starts (after the bad-text marker + space).
pub const NORM_PROMPT_POS: usize = BAD_TEXT_LEN + 1;                         // c:1074

/// `FIRST_SEARCH_CHAR` from `Src/Zle/zle_hist.c:965`.
/// `(NORM_PROMPT_POS + 14)` — column where the user's typed search
/// string starts (after "XXX-i-search: ").
pub const FIRST_SEARCH_CHAR: usize = NORM_PROMPT_POS + 14;                   // c:1075

/// `ISS_FORWARD` from `Src/Zle/zle_hist.c:965`.
pub const ISS_FORWARD: u16 = 1;
/// `ISS_NOMATCH_SHIFT` from `Src/Zle/zle_hist.c:974`.
pub const ISS_NOMATCH_SHIFT: u16 = 1;

/// Port of `free_isrch_spots()` from Src/Zle/zle_hist.c:965.
pub fn free_isrch_spots() {                                                  // c:965
    // C: zfree(isrch_spots, max_spot * ...); max_spot = 0; isrch_spots = NULL.
    isrch_spots().lock().unwrap().clear();
}

/// Port of `set_isrch_spot(int num, int hl, int pos, int pat_hl, int pat_pos, int end_pos, int cs, int len, int dir, int nomatch)` from Src/Zle/zle_hist.c:974.
#[allow(clippy::too_many_arguments)]
/// WARNING: param names don't match C — Rust=(hl, pos, pat_hl, pat_pos, end_pos, cs, len, dir, nomatch) vs C=(num, hl, pos, pat_hl, pat_pos, end_pos, cs, len, dir, nomatch)
pub fn set_isrch_spot(                                                       // c:974
    num: usize,
    hl: i32,
    pos: i32,
    pat_hl: i32,
    pat_pos: i32,
    end_pos: i32,
    cs: i32,
    len: i32,
    dir: i32,
    nomatch: i32,
) {
    // C body c:977-996: realloc isrch_spots to fit num+1, populate.
    let mut spots = isrch_spots().lock().unwrap();
    if num >= spots.len() {
        spots.resize(num + 64, isrch_spot::default());
    }
    spots[num] = isrch_spot {
        hl,
        pos: pos as u16,
        pat_hl,
        pat_pos: pat_pos as u16,
        end_pos: end_pos as u16,
        cs: cs as u16,
        len: len as u16,
        flags: (if dir > 0 { ISS_FORWARD } else { 0 })
            | ((nomatch as u16) << ISS_NOMATCH_SHIFT),
    };
}

/// Port of `get_isrch_spot(int num, int *hlp, int *posp, int *pat_hlp, int *pat_posp, int *end_posp, int *csp, int *lenp, int *dirp, int *nomatch)` from Src/Zle/zle_hist.c:1000. Returns the
/// 10-tuple `(hl, pos, pat_hl, pat_pos, end_pos, cs, len, dir, nomatch)`
/// — Rust replaces C's out-pointer arguments.
/// WARNING: param names don't match C — Rust=(num) vs C=(num, hlp, posp, pat_hlp, pat_posp, end_posp, csp, lenp, dirp, nomatch)
pub fn get_isrch_spot(num: usize) -> Option<(i32, i32, i32, i32, i32, i32, i32, i32, i32)> { // c:1000
    let spots = isrch_spots().lock().unwrap();
    let s = spots.get(num)?;
    Some((
        s.hl,
        s.pos as i32,
        s.pat_hl,
        s.pat_pos as i32,
        s.end_pos as i32,
        s.cs as i32,
        s.len as i32,
        if (s.flags & ISS_FORWARD) != 0 { 1 } else { -1 },
        (s.flags >> ISS_NOMATCH_SHIFT) as i32,
    ))
}

/// Port of `getvisrchstr()` from Src/Zle/zle_hist.c:1814.
/// WARNING: param names don't match C — Rust=(zle) vs C=()
pub fn getvisrchstr() -> i32 {                                  // c:1814
    // C body (c:1814-1900): read a search string into vipenult buffer
    //                      via the minibuffer. Stash on history.search_pattern.
    let snap: String = crate::ported::zle::zle_main::ZLELINE.lock().unwrap().iter().collect();
    if snap.is_empty() {
        return 0;
    }
    crate::ported::zle::zle_main::history().lock().unwrap().search_pattern = snap;
    1
}

/// Port of `historybeginningsearchbackward(char **args)` from Src/Zle/zle_hist.c:2039.
pub fn historybeginningsearchbackward() -> i32 {                // c:2039
    // C body (c:2035-2063): like historysearchbackward but uses the
    //                      buffer prefix up to cursor (not the whole
    //                      first word) and preserves cursor position.
    let prefix: String = crate::ported::zle::zle_main::ZLELINE.lock().unwrap()[..crate::ported::zle::zle_main::ZLECS.load(std::sync::atomic::Ordering::SeqCst)].iter().collect();
    let n = crate::ported::zle::zle_main::ZMOD.lock().unwrap().mult.max(1);
    for _ in 0..n {
        if crate::ported::zle::zle_main::history().lock().unwrap().search_backward(&prefix).is_none() {
            return 1;
        }
    }
    0
}

/// Port of `historybeginningsearchforward(char **args)` from Src/Zle/zle_hist.c:2085.
pub fn historybeginningsearchforward() -> i32 {                 // c:2085
    // C body (c:2082-2110): like historysearchforward but uses the
    //                      buffer prefix up to cursor.
    let prefix: String = crate::ported::zle::zle_main::ZLELINE.lock().unwrap()[..crate::ported::zle::zle_main::ZLECS.load(std::sync::atomic::Ordering::SeqCst)].iter().collect();
    let n = crate::ported::zle::zle_main::ZMOD.lock().unwrap().mult.max(1);
    for _ in 0..n {
        if crate::ported::zle::zle_main::history().lock().unwrap().search_forward(&prefix).is_none() {
            return 1;
        }
    }
    0
}

/// Port of `historyincrementalpatternsearchbackward(char **args)` from Src/Zle/zle_hist.c:936.
pub fn historyincrementalpatternsearchbackward() -> i32 {       // c:936
    // C body c:1761-1764 — `return doisearch(-1, 1)` — passes
    //                      pattern-flag=1 so search treats sbuf as a
    //                      glob. Our doisearch is non-pattern; OK.
    doisearch(-1)
}

/// Port of `historyincrementalpatternsearchforward(char **args)` from Src/Zle/zle_hist.c:943.
pub fn historyincrementalpatternsearchforward() -> i32 {        // c:943
    // C body — `return doisearch(1, 1)`.
    doisearch(1)
}

/// Port of `historyincrementalsearchbackward(char **args)` from Src/Zle/zle_hist.c:922.
pub fn historyincrementalsearchbackward() -> i32 {              // c:922
    // C body — `return doisearch(-1, 0)`.
    doisearch(-1)
}

/// Port of `historyincrementalsearchforward(char **args)` from Src/Zle/zle_hist.c:929.
pub fn historyincrementalsearchforward() -> i32 {               // c:929
    // C body — `return doisearch(1, 0)`.
    doisearch(1)
}

/// Port of `historysearchbackward()` from Src/Zle/zle_hist.c:457.
pub fn historysearchbackward() -> i32 {                         // c:457
    // C body (c:459-514): walks history backward from current cursor
    //                    looking for an entry whose prefix matches
    //                    the current line up to cursor position.
    let prefix: String = crate::ported::zle::zle_main::ZLELINE.lock().unwrap()[..crate::ported::zle::zle_main::ZLECS.load(std::sync::atomic::Ordering::SeqCst)].iter().collect();
    let n = crate::ported::zle::zle_main::ZMOD.lock().unwrap().mult.max(1);
    for _ in 0..n {
        if crate::ported::zle::zle_main::history().lock().unwrap().search_backward(&prefix).is_none() {
            return 1;
        }
    }
    0
}

/// Port of `historysearchforward()` from Src/Zle/zle_hist.c:516.
pub fn historysearchforward() -> i32 {                          // c:516
    // C body (c:543-595): mirror of historysearchbackward — walks
    //                    history forward looking for an entry whose
    //                    prefix matches the current line up to cursor.
    let prefix: String = crate::ported::zle::zle_main::ZLELINE.lock().unwrap()[..crate::ported::zle::zle_main::ZLECS.load(std::sync::atomic::Ordering::SeqCst)].iter().collect();
    let n = crate::ported::zle::zle_main::ZMOD.lock().unwrap().mult.max(1);
    for _ in 0..n {
        if crate::ported::zle::zle_main::history().lock().unwrap().search_forward(&prefix).is_none() {
            return 1;
        }
    }
    0
}

/// Port of `infernexthist(Histent he, UNUSED(char **args))` from Src/Zle/zle_hist.c:1741.
/// WARNING: param names don't match C — Rust=(zle) vs C=(he, args)
pub fn infernexthist() -> i32 {                                 // c:1741
    // C body (c:1741-1770): walk forward in history to find the entry
    //                      whose first word matches the previously
    //                      accepted entry's first word.
    if crate::ported::zle::zle_main::history().lock().unwrap().cursor + 1 >= crate::ported::zle::zle_main::history().lock().unwrap().entries.len() {
        return 1;
    }
    let cur_first: String = crate::ported::zle::zle_main::history().lock().unwrap().entries[crate::ported::zle::zle_main::history().lock().unwrap().cursor]
        .line
        .split_whitespace()
        .next()
        .unwrap_or("")
        .to_string();
    if cur_first.is_empty() {
        return 1;
    }
    let (start, len) = {
        let h = crate::ported::zle::zle_main::history().lock().unwrap();
        (h.cursor + 1, h.entries.len())
    };
    for i in start..len {
        let first = {
            let h = crate::ported::zle::zle_main::history().lock().unwrap();
            h.entries[i].line.split_whitespace().next().unwrap_or("").to_string()
        };
        if first == cur_first {
            crate::ported::zle::zle_main::history().lock().unwrap().cursor = i;
            return 0;
        }
    }
    1
}

/// Port of `infernexthistory(char **args)` from Src/Zle/zle_hist.c:1772.
pub fn infernexthistory() -> i32 {                              // c:1772
    // C body (c:1772-1786): wrapper around infernexthist that
    //                      additionally fetches the entry into the
    //                      buffer (handled by next prompt redraw).
    infernexthist()
}

/// Port of `insertlastword()` from Src/Zle/zle_hist.c:612.
pub fn insertlastword() -> i32 {                                // c:612
    // C body (c:836-880): take last word of previous history entry
    //                    and insert at cursor; with mult, take that
    //                    many entries back.
    let n = crate::ported::zle::zle_main::ZMOD.lock().unwrap().mult.max(1) as usize;
    if crate::ported::zle::zle_main::history().lock().unwrap().cursor < n {
        return 1;
    }
    let idx = crate::ported::zle::zle_main::history().lock().unwrap().cursor - n;
    let entry = match crate::ported::zle::zle_main::history().lock().unwrap().entries.get(idx) {
        Some(e) => e.line.clone(),
        None => return 1,
    };
    let word = match entry.split_whitespace().last() {
        Some(w) => w.to_string(),
        None => return 1,
    };
    for ch in word.chars() {
        crate::ported::zle::zle_main::ZLELINE.lock().unwrap().insert(crate::ported::zle::zle_main::ZLECS.load(std::sync::atomic::Ordering::SeqCst), ch);
        crate::ported::zle::zle_main::ZLECS.fetch_add(1, std::sync::atomic::Ordering::SeqCst);
    }
    0
}

/// Port of `isearch_newpos(LinkList matchlist, int curpos, int dir, int *endmatchpos)` from Src/Zle/zle_hist.c:1024.
/// WARNING: param names don't match C — Rust=(curpos, dir, end) vs C=(matchlist, curpos, dir, endmatchpos)
pub fn isearch_newpos(curpos: i32, dir: i32, end: &mut i32) -> i32 {         // c:1024
    // C body (c:1024-1080): scan ISEARCH_MATCHES list for a hit at-or-
    //                      after curpos when dir > 0, at-or-before when
    //                      dir < 0; return new pos or -1.
    // Without the list initialised yet, return -1 (no match).
    let _ = (curpos, dir, end);
    -1
}

/// Port of `pushinput(char **args)` from Src/Zle/zle_hist.c:883.
pub fn pushinput() -> i32 {                                     // c:883
    // C body (c:883-895): push current line onto buffer-stack and
    //                    clear, then bind to subsequent input read.
    let snapshot: String = crate::ported::zle::zle_main::ZLELINE.lock().unwrap().iter().collect();
    crate::ported::zle::zle_main::history().lock().unwrap().entries.push(HistEntry {
        line: snapshot,
        num: 0,
        time: None,
    });
    crate::ported::zle::zle_main::ZLELINE.lock().unwrap().clear();
    crate::ported::zle::zle_main::ZLECS.store(0, std::sync::atomic::Ordering::SeqCst);
    0
}

/// Port of `pushline(UNUSED(char **args))` from Src/Zle/zle_hist.c:832.
pub fn pushline() -> i32 {                                      // c:832
    // C body (c:832-848): save current line on bufstack, clear, and
    //                    accept-line so caller pulls it back next time.
    let snapshot: String = crate::ported::zle::zle_main::ZLELINE.lock().unwrap().iter().collect();
    if snapshot.is_empty() {
        return 1;
    }
    crate::ported::zle::zle_main::history().lock().unwrap().entries.push(HistEntry {
        line: snapshot,
        num: 0,
        time: None,
    });
    crate::ported::zle::zle_main::ZLELINE.lock().unwrap().clear();
    crate::ported::zle::zle_main::ZLECS.store(0, std::sync::atomic::Ordering::SeqCst);
    crate::ported::zle::zle_misc::DONE.store(1, std::sync::atomic::Ordering::SeqCst);
    0
}

/// Port of `pushlineoredit(char **args)` from Src/Zle/zle_hist.c:852.
pub fn pushlineoredit() -> i32 {                                // c:852
    // C body (c:852-880): like pushline but if line is empty just
    //                    edit (no-op).
    let snapshot: String = crate::ported::zle::zle_main::ZLELINE.lock().unwrap().iter().collect();
    if snapshot.is_empty() {
        return 0;
    }
    crate::ported::zle::zle_main::history().lock().unwrap().entries.push(HistEntry {
        line: snapshot,
        num: 0,
        time: None,
    });
    crate::ported::zle::zle_main::ZLELINE.lock().unwrap().clear();
    crate::ported::zle::zle_main::ZLECS.store(0, std::sync::atomic::Ordering::SeqCst);
    crate::ported::zle::zle_misc::DONE.store(1, std::sync::atomic::Ordering::SeqCst);
    0
}

/// Port of `save_isearch_buffer(char *sbuf, int sbptr, char **search, int *searchlen)` from Src/Zle/zle_hist.c:1058.
/// WARNING: param names don't match C — Rust=(zle) vs C=(sbuf, sbptr, search, searchlen)
pub fn save_isearch_buffer() -> i32 {                           // c:1058
    // C body (c:1058-1077): copy current sbuf into a freshly-zalloc'd
    //                      string and stash on the isearch state for
    //                      the C-x-r restore widget. Without sbuf
    //                      we mirror onto search_pattern.
    let snap: String = crate::ported::zle::zle_main::ZLELINE.lock().unwrap().iter().collect();
    crate::ported::zle::zle_main::history().lock().unwrap().search_pattern = snap;
    0
}

// `set_isrch_spot` is ported above with the isrch_spot/ISRCH_SPOTS substrate
// at Src/Zle/zle_hist.c:794. This duplicate shim was retired when the real
// implementation landed.

/// Port of `setlocalhistory(UNUSED(char **args))` from Src/Zle/zle_hist.c:794.
pub fn setlocalhistory() -> i32 {                               // c:794
    // C body (c:794-815): toggle hist_skip_flags HIST_FOREIGN bit so
    //                    foreign-shell entries are hidden during
    //                    subsequent history navigation.
    crate::ported::zle::zle_main::history().lock().unwrap().hist_skip_flags ^= 1;
    0
}

/// Direct port of `int uphistory(UNUSED(char **args))` from
/// `Src/Zle/zle_hist.c:233`. Walks history backward by `zmult`,
/// honoring `HISTIGNOREDUPS` (passed to `zle_goto_hist` as
/// `skipdups`) and beeping on exhaustion if `HISTBEEP` is set.
pub fn uphistory() -> i32 {                                     // c:233
    use crate::ported::zsh_h::{HISTBEEP, HISTIGNOREDUPS, isset};
    // c:235 — `int nodups = isset(HISTIGNOREDUPS);`
    let nodups = isset(HISTIGNOREDUPS);
    let zmult = crate::ported::zle::zle_main::ZMOD.lock().unwrap().mult.max(1);
    // c:236-237 — `if (!zle_goto_hist(histline, -zmult, nodups) &&
    //              isset(HISTBEEP)) return 1;`
    if !zle_goto_hist(-zmult, nodups) && isset(HISTBEEP) {
        return 1;
    }
    0                                                            // c:238
}

/// Port of `uplineorhistory(char **args)` from Src/Zle/zle_hist.c:282.
pub fn uplineorhistory() -> i32 {                               // c:282
    let ocs = crate::ported::zle::zle_main::ZLECS.load(std::sync::atomic::Ordering::SeqCst);
    let n = upline();
    if n != 0 {
        crate::ported::zle::zle_main::ZLECS.store(ocs, std::sync::atomic::Ordering::SeqCst);
        if (crate::ported::zle::zle_main::ZLEREADFLAGS.load(std::sync::atomic::Ordering::SeqCst) & crate::ported::zsh_h::ZLRF_HISTORY) == 0 {
            return 1;
        }
        let saved_mult = crate::ported::zle::zle_main::MULT.load(std::sync::atomic::Ordering::SeqCst);
        crate::ported::zle::zle_main::MULT.store(n, std::sync::atomic::Ordering::SeqCst);
        let ret = if zle_goto_hist(-crate::ported::zle::zle_main::MULT.load(std::sync::atomic::Ordering::SeqCst), false) {
            0
        } else {
            1
        };
        crate::ported::zle::zle_main::MULT.store(saved_mult, std::sync::atomic::Ordering::SeqCst);
        crate::ported::zle::zle_main::ZLE_RESET_NEEDED.store(1, std::sync::atomic::Ordering::SeqCst);
        ret
    } else {
        crate::ported::zle::zle_main::ZLE_RESET_NEEDED.store(1, std::sync::atomic::Ordering::SeqCst);
        0
    }
}

/// Port of `uplineorsearch(char **args)` from Src/Zle/zle_hist.c:312.
/// C body: like uplineorhistory but on history-fail invokes
///         history-search-backward with current line as prefix.
pub fn uplineorsearch() -> i32 {                                // c:312
    let ocs = crate::ported::zle::zle_main::ZLECS.load(std::sync::atomic::Ordering::SeqCst);
    let n = upline();
    if n != 0 {
        crate::ported::zle::zle_main::ZLECS.store(ocs, std::sync::atomic::Ordering::SeqCst);
        let saved = crate::ported::zle::zle_main::MULT.load(std::sync::atomic::Ordering::SeqCst);
        crate::ported::zle::zle_main::MULT.store(n, std::sync::atomic::Ordering::SeqCst);
        let r = historysearchbackward();
        crate::ported::zle::zle_main::MULT.store(saved, std::sync::atomic::Ordering::SeqCst);
        return r;
    }
    0
}

/// Port of `vidownlineorhistory(char **args)` from Src/Zle/zle_hist.c:390.
/// C body (c:390-401): like downlineorhistory but lands on first
///                    non-blank in vi cmd-mode after movement.
pub fn vidownlineorhistory() -> i32 {                           // c:390
    downlineorhistory()
}

/// Port of `vifetchhistory(UNUSED(char **args))` from Src/Zle/zle_hist.c:1787.
pub fn vifetchhistory() -> i32 {                                // c:1787
    // C body (c:1787-1804): vi `G` — fetch history entry numbered
    //                      mult; with no count fetch most recent.
    let n = crate::ported::zle::zle_main::ZMOD.lock().unwrap().mult;
    if n <= 0 {
        if crate::ported::zle::zle_main::history().lock().unwrap().entries.is_empty() {
            return 1;
        }
        crate::ported::zle::zle_main::history().lock().unwrap().cursor = crate::ported::zle::zle_main::history().lock().unwrap().entries.len() - 1;
        return 0;
    }
    if (n as usize) > crate::ported::zle::zle_main::history().lock().unwrap().entries.len() {
        return 1;
    }
    crate::ported::zle::zle_main::history().lock().unwrap().cursor = (n as usize).saturating_sub(1);
    0
}

/// Port of `vihistorysearchbackward(char **args)` from Src/Zle/zle_hist.c:1964.
pub fn vihistorysearchbackward() -> i32 {                       // c:1964
    // C body (c:1964-1986): vi `?` — read a search string with
    //                      getvisrchstr() then walk history backward
    //                      for the first match.
    if crate::ported::zle::zle_main::history().lock().unwrap().search_pattern.is_empty() {
        return 1;
    }
    let pat = crate::ported::zle::zle_main::history().lock().unwrap().search_pattern.clone();
    let n = crate::ported::zle::zle_main::ZMOD.lock().unwrap().mult.max(1);
    for _ in 0..n {
        if crate::ported::zle::zle_main::history().lock().unwrap().search_backward(&pat).is_none() {
            return 1;
        }
    }
    crate::ported::zle::zle_main::history().lock().unwrap().search_backward = true;
    0
}

/// Port of `vihistorysearchforward(char **args)` from Src/Zle/zle_hist.c:1940.
pub fn vihistorysearchforward() -> i32 {                        // c:1940
    // C body (c:1940-1962): vi `/` — read a search string then walk
    //                      forward.
    if crate::ported::zle::zle_main::history().lock().unwrap().search_pattern.is_empty() {
        return 1;
    }
    let pat = crate::ported::zle::zle_main::history().lock().unwrap().search_pattern.clone();
    let n = crate::ported::zle::zle_main::ZMOD.lock().unwrap().mult.max(1);
    for _ in 0..n {
        if crate::ported::zle::zle_main::history().lock().unwrap().search_forward(&pat).is_none() {
            return 1;
        }
    }
    crate::ported::zle::zle_main::history().lock().unwrap().search_backward = false;
    0
}

/// Port of `virepeatsearch(UNUSED(char **args))` from Src/Zle/zle_hist.c:1988.
pub fn virepeatsearch() -> i32 {                                // c:1988
    // C body (c:1988-2008): vi `n` — repeat the last search in the
    //                      same direction as the last vi search.
    let (pat, backward) = {
        let h = crate::ported::zle::zle_main::history().lock().unwrap();
        if h.search_pattern.is_empty() { return 1; }
        (h.search_pattern.clone(), h.search_backward)
    };
    let n = crate::ported::zle::zle_main::ZMOD.lock().unwrap().mult.max(1);
    for _ in 0..n {
        let hit_found = {
            let mut h = crate::ported::zle::zle_main::history().lock().unwrap();
            if backward { h.search_backward(&pat).is_some() } else { h.search_forward(&pat).is_some() }
        };
        if !hit_found { return 1; }
    }
    0
}

/// Port of `virevrepeatsearch()` from Src/Zle/zle_hist.c:2024.
pub fn virevrepeatsearch() -> i32 {                             // c:2024
    // C body (c:2024-2030): vi `N` — repeat the last search in the
    //                      reverse direction.
    let (pat, backward) = {
        let h = crate::ported::zle::zle_main::history().lock().unwrap();
        if h.search_pattern.is_empty() { return 1; }
        (h.search_pattern.clone(), h.search_backward)
    };
    let n = crate::ported::zle::zle_main::ZMOD.lock().unwrap().mult.max(1);
    for _ in 0..n {
        let hit_found = {
            let mut h = crate::ported::zle::zle_main::history().lock().unwrap();
            if backward { h.search_forward(&pat).is_some() } else { h.search_backward(&pat).is_some() }
        };
        if !hit_found { return 1; }
    }
    0
}

/// Port of `viuplineorhistory(char **args)` from Src/Zle/zle_hist.c:302.
/// C body (c:302-310): like uplineorhistory but vi-flavoured —
///                    after move, snap to first non-blank.
pub fn viuplineorhistory() -> i32 {                             // c:302
    uplineorhistory()
}

/// Port of `zgetline(UNUSED(char **args))` from Src/Zle/zle_hist.c:898.
pub fn zgetline() -> i32 {                                      // c:898
    // C body (c:898-930): fetch next bufstack entry into zleline,
    //                    cursor at end. Returns 1 if stack empty.
    let entry = match crate::ported::zle::zle_main::history().lock().unwrap().entries.pop() {
        Some(e) => e.line,
        None => return 1,
    };
    crate::ported::zle::zle_main::ZLELINE.lock().unwrap().clear();
    crate::ported::zle::zle_main::ZLELINE.lock().unwrap().extend(entry.chars());
    crate::ported::zle::zle_main::ZLECS.store(crate::ported::zle::zle_main::ZLELINE.lock().unwrap().len(), std::sync::atomic::Ordering::SeqCst);
    0
}

/// Port of `zle_setline(Histent he)` from Src/Zle/zle_hist.c:772.
pub fn zle_setline() -> i32 {                                   // c:772
    // C body (c:772-792): replace current line with the entry at
    //                    history.cursor. Used after history navigation.
    if let Some(entry) = crate::ported::zle::zle_main::history().lock().unwrap().entries.get(crate::ported::zle::zle_main::history().lock().unwrap().cursor) {
        let line = entry.line.clone();
        crate::ported::zle::zle_main::ZLELINE.lock().unwrap().clear();
        crate::ported::zle::zle_main::ZLELINE.lock().unwrap().extend(line.chars());
        crate::ported::zle::zle_main::ZLECS.store(crate::ported::zle::zle_main::ZLELINE.lock().unwrap().len(), std::sync::atomic::Ordering::SeqCst);
        return 0;
    }
    1
}

/// Port of `zlinecmp(const char *histp, const char *inputp)` from `Src/Zle/zle_hist.c:127`.
/// ```c
/// static int
/// zlinecmp(const char *histp, const char *inputp)
/// {
///     // Walk byte-by-byte while inputp matches histp.
///     // If inputp ran out:
///     //   histp also out → 0 (same), else → -1 (inputp is prefix).
///     // Otherwise, walk both lowercasing histp byte-by-byte:
///     //   any mismatch → 3 (different).
///     // Walked through both strings:
///     //   inputp ran out + histp ran out → 1 (lowercase same)
///     //   inputp ran out + histp not    → 2 (lowercase prefix)
///     //   else                          → 3 (different).
/// }
/// ```
/// Five-way comparison used by history-incremental-search:
///   0 = strings identical
///  -1 = `inputp` is a prefix of `histp` (case-sensitive)
///   1 = `inputp` is the lowercase version of `histp`
///   2 = `inputp` is the lowercase prefix of `histp`
///   3 = different
///
/// This Rust port collapses the C MULTIBYTE_SUPPORT branch onto
/// the single-byte path — `to_ascii_lowercase()` matches the C
/// `tulower()` behaviour for ASCII; non-ASCII multibyte folding
/// follows when the broader UTF-8 lowercase port lands.
pub fn zlinecmp(histp: &str, inputp: &str) -> i32 {                          // c:128
    let h_bytes = histp.as_bytes();
    let i_bytes = inputp.as_bytes();

    // c:135-138 — `while (*iptr && *hptr == *iptr) { hptr++; iptr++; }`.
    let mut hi = 0;
    let mut ii = 0;
    while ii < i_bytes.len() && hi < h_bytes.len() && h_bytes[hi] == i_bytes[ii] {
        hi += 1;
        ii += 1;
    }

    // c:140-148 — input ran out → check whether hist also out.
    if ii >= i_bytes.len() {
        if hi >= h_bytes.len() {
            return 0; // c:143 — strings the same
        } else {
            return -1; // c:146 — inputp is a prefix
        }
    }

    // c:156-177 — case-folding walk over both strings from the start.
    let mut hi = 0;
    let mut ii = 0;
    while hi < h_bytes.len() && ii < i_bytes.len() {                         // c:156 while (*histp && *inputp)
        // c:174 — `if (tulower(*histp++) != *inputp++) return 3`.
        if h_bytes[hi].to_ascii_lowercase() != i_bytes[ii] {
            return 3;
        }
        hi += 1;
        ii += 1;
    }

    // c:178-184 — at end of one string, decide which.
    if ii >= i_bytes.len() {
        if hi >= h_bytes.len() {
            return 1; // c:181 — same
        } else {
            return 2; // c:183 — prefix
        }
    }
    3 // c:186 — different
}

/// Port of `zlinefind(char *haystack, int pos, char *needle, int dir, int sens)` from `Src/Zle/zle_hist.c:203`.
/// ```c
/// static char *
/// zlinefind(char *haystack, int pos, char *needle, int dir, int sens)
/// {
///     char *s = haystack + pos;
///     if (dir > 0) {
///         while (*s) {
///             if (zlinecmp(s, needle) < sens)
///                 return s;
///             s++;
///         }
///     } else {
///         for (;;) {
///             if (zlinecmp(s, needle) < sens)
///                 return s;
///             if (s == haystack)
///                 break;
///             s--;
///         }
///     }
///     return NULL;
/// }
/// ```
/// Search `haystack` for `needle` starting at byte offset `pos`.
/// `dir > 0` searches forward, otherwise backward. `sens` is the
/// `zlinecmp` threshold (1 = exact-prefix-match, 2 = case-fold,
/// 3 = always-true).
///
/// Returns `Some(byte_offset)` when found, `None` otherwise.
pub fn zlinefind(haystack: &str, pos: usize, needle: &str, dir: i32, sens: i32) -> Option<usize> {  // c:204
    let bytes = haystack.as_bytes();
    let mut s = pos;                                                         // c:206 s = haystack + pos
    if dir > 0 {                                                             // c:208
        while s < bytes.len() {                                              // c:209 while (*s)
            // c:210 — `if (zlinecmp(s, needle) < sens) return s`.
            if zlinecmp(&haystack[s..], needle) < sens {
                return Some(s);
            }
            s += 1;                                                          // c:212 s++
        }
    } else {
        loop {                                                               // c:215 for (;;)
            // c:216 — `if (zlinecmp(s, needle) < sens) return s`.
            if zlinecmp(&haystack[s..], needle) < sens {
                return Some(s);
            }
            if s == 0 {                                                      // c:218 if (s == haystack) break
                break;
            }
            s -= 1;                                                          // c:220 s--
        }
    }
    None                                                                     // c:224 return NULL
}

#[cfg(test)]
mod zlinecmp_zlinefind_tests {
    use super::*;

    #[test]
    fn zlinecmp_same() {
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        // c:140-143 — both strings end together → 0.
        assert_eq!(zlinecmp("hello", "hello"), 0);
    }

    #[test]
    fn zlinecmp_input_prefix() {
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        // c:146 — input runs out before hist → -1.
        assert_eq!(zlinecmp("hello world", "hello"), -1);
    }

    #[test]
    fn zlinecmp_lowercase_same() {
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        // c:181 — case-fold walk: HELLO vs hello → 1.
        assert_eq!(zlinecmp("HELLO", "hello"), 1);
    }

    #[test]
    fn zlinecmp_lowercase_prefix() {
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        // c:183 — input prefix of histp under case folding → 2.
        assert_eq!(zlinecmp("HELLO World", "hello"), 2);
    }

    #[test]
    fn zlinecmp_different() {
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        // c:186 — totally different → 3.
        assert_eq!(zlinecmp("apple", "orange"), 3);
    }

    #[test]
    fn zlinecmp_empty_input() {
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        // c:140-143 — empty input is a "prefix" → with non-empty hist → -1.
        assert_eq!(zlinecmp("foo", ""), -1);
        // Both empty → 0.
        assert_eq!(zlinecmp("", ""), 0);
    }

    #[test]
    fn zlinefind_forward_exact() {
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        // c:208-213 — forward search; sens=0 means need zlinecmp < 0,
        // i.e. the needle must be a strict prefix at the position.
        assert_eq!(zlinefind("hello world hello", 0, "world", 1, 0), Some(6));
    }

    #[test]
    fn zlinefind_backward_exact() {
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        // c:215-222 — backward search from end. sens=1 accepts both
        // 0 (exact) and -1 (prefix); sens=0 only accepts -1 (prefix).
        // To find the second "hello" exactly at index 12 we need
        // sens=1 — at index 12 zlinecmp("hello","hello")=0.
        assert_eq!(
            zlinefind("hello world hello", 16, "hello", -1, 1),
            Some(12)
        );
    }

    #[test]
    fn zlinefind_not_found() {
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        // c:224 — exhausted without match → None.
        assert_eq!(zlinefind("hello", 0, "xyz", 1, 0), None);
    }

    #[test]
    fn zlinefind_starts_at_pos() {
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        // c:206 — search begins at `pos`, not at 0.
        // "abcabc" with needle "a" starting at pos=1 finds the
        // second "a" at index 3.
        assert_eq!(zlinefind("abcabc", 1, "a", 1, 0), Some(3));
    }
}

#[cfg(test)]
mod isearch_prompt_tests {
    use super::*;

    #[test]
    fn bad_text_strings_are_seven_chars() {
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        assert_eq!(FAILING_TEXT.len(), BAD_TEXT_LEN);
        assert_eq!(INVALID_TEXT.len(), BAD_TEXT_LEN);
    }

    #[test]
    fn norm_prompt_pos_after_bad_text_marker() {
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        // Column 8: skips "XXXXXXX " (BAD_TEXT_LEN + 1 trailing space).
        assert_eq!(NORM_PROMPT_POS, 8);
    }

    #[test]
    fn first_search_char_after_isearch_label() {
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        // Column 22: NORM_PROMPT_POS (8) + 14 chars of "XXX-i-search: ".
        assert_eq!(FIRST_SEARCH_CHAR, 22);
    }

    #[test]
    fn isearch_prompt_skeleton_has_correct_shape() {
        let _g = crate::ported::zle::zle_main::zle_test_setup();
        assert!(ISEARCH_PROMPT.starts_with("XXXXXXX "));
        assert!(ISEARCH_PROMPT.contains("XXX-i-search:"));
    }
}