/* linenoise.c -- guerrilla line editing library against the idea that a
 * line editing lib needs to be 20,000 lines of C code.
 *
 * You can find the latest source code at:
 *
 *   http://github.com/antirez/linenoise
 *
 * Does a number of crazy assumptions that happen to be true in 99.9999% of
 * the 2010 UNIX computers around.
 *
 * ------------------------------------------------------------------------
 *
 * Copyright (c) 2010-2016, Salvatore Sanfilippo <antirez at gmail dot com>
 * Copyright (c) 2010-2013, Pieter Noordhuis <pcnoordhuis at gmail dot com>
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *  *  Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *  *  Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * ------------------------------------------------------------------------
 *
 * References:
 * - http://invisible-island.net/xterm/ctlseqs/ctlseqs.html
 * - http://www.3waylabs.com/nw/WWW/products/wizcon/vt220.html
 *
 * List of escape sequences used by this program, we do everything just
 * with three sequences. In order to be so cheap we may have some
 * flickering effect with some slow terminal, but the lesser sequences
 * the more compatible.
 *
 * EL (Erase Line)
 *    Sequence: ESC [ n K
 *    Effect: if n is 0 or missing, clear from cursor to end of line
 *    Effect: if n is 1, clear from beginning of line to cursor
 *    Effect: if n is 2, clear entire line
 *
 * CUF (CUrsor Forward)
 *    Sequence: ESC [ n C
 *    Effect: moves cursor forward n chars
 *
 * CUB (CUrsor Backward)
 *    Sequence: ESC [ n D
 *    Effect: moves cursor backward n chars
 *
 * The following is used to get the terminal width if getting
 * the width with the TIOCGWINSZ ioctl fails
 *
 * DSR (Device Status Report)
 *    Sequence: ESC [ 6 n
 *    Effect: reports the current cusor position as ESC [ n ; m R
 *            where n is the row and m is the column
 *
 * When multi line mode is enabled, we also use an additional escape
 * sequence. However multi line editing is disabled by default.
 *
 * CUU (Cursor Up)
 *    Sequence: ESC [ n A
 *    Effect: moves cursor up of n chars.
 *
 * CUD (Cursor Down)
 *    Sequence: ESC [ n B
 *    Effect: moves cursor down of n chars.
 *
 * When linenoiseClearScreen() is called, two additional escape sequences
 * are used in order to clear the screen and position the cursor at home
 * position.
 *
 * CUP (Cursor position)
 *    Sequence: ESC [ H
 *    Effect: moves the cursor to upper left corner
 *
 * ED (Erase display)
 *    Sequence: ESC [ 2 J
 *    Effect: clear the whole screen
 *
 */

#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <ctype.h>
#include <stdint.h>
#include <stdbool.h>
#include <console/utils.h>
#include "console_linenoise.h"

extern void console_internal_error_print(const char *msg);

#define ln_read(buf, cap)   (ls->read ? ls->read(ls->rwctx, buf, cap) : -1)
#define ln_write(text, len) (ls->write ? ls->write(ls->rwctx, text, len) : -1)
#define ln_writez(text) ln_write(text, strlen(text))

void consLnStateInit(struct linenoiseState *ls)
{
    bzero(ls, sizeof(struct linenoiseState));
    ls->mlmode = false;  /* Multi line mode. Default is single line. */
    ls->dumbmode = false; /* Dumb mode where line editing is disabled. Off by default */
    ls->echomode = true; /* Echo (meaningful only in dumb mode) */
    ls->history_max_len = 16;
    ls->history_len = 0;
    ls->allowCtrlDExit = true;
    ls->history = NULL;
    ls->buf = NULL;         /* Edited line buffer. */
    ls->buflen = 0;         /* Edited line buffer size. */
    ls->prompt = NULL;      /* Prompt to display. */
    ls->plen = 0;           /* Prompt length. */
    ls->pos = 0;            /* Current cursor position. */
    ls->oldpos = 0;         /* Previous refresh cursor position. */
    ls->len = 0;            /* Current edited line length. */
    ls->cols = 0;           /* Number of columns in terminal. */
    ls->maxrows = 0;        /* Maximum num of rows used so far (multiline mode) */
    ls->history_index = 0;  /* The history index we are currently editing. */
    ls->rwctx = NULL;
    ls->read = NULL;
    ls->write = NULL;
}

enum KEY_ACTION {
    KEY_NULL = 0,        /* NULL */
    CTRL_A = 1,         /* Ctrl+a */
    CTRL_B = 2,         /* Ctrl-b */
    CTRL_C = 3,         /* Ctrl-c */
    CTRL_D = 4,         /* Ctrl-d */
    CTRL_E = 5,         /* Ctrl-e */
    CTRL_F = 6,         /* Ctrl-f */
    CTRL_H = 8,         /* Ctrl-h */
    TAB = 9,            /* Tab */
    CTRL_K = 11,        /* Ctrl+k */
    CTRL_L = 12,        /* Ctrl+l */
    ENTER = 10,         /* Enter */
    RETURN = 13,         /* LF */
    CTRL_N = 14,        /* Ctrl-n */
    CTRL_P = 16,        /* Ctrl-p */
    CTRL_T = 20,        /* Ctrl-t */
    CTRL_U = 21,        /* Ctrl+u */
    CTRL_W = 23,        /* Ctrl+w */
    ESC = 27,           /* Escape */
    BACKSPACE = 127    /* Backspace */
};

static void refreshLine(struct linenoiseState *ls);

/* ======================= Low level terminal handling ====================== */

/* Try to get the number of columns in the current terminal, or assume 80
 * if it fails. */
static inline int getColumns()
{
    return 80;
}

/* Clear the screen. Used to handle ctrl+l */
void consLnClearScreen(struct linenoiseState *ls)
{
    ln_writez("\x1b[H\x1b[2J");
}

/* Beep, used for completion when there is nothing to complete or when all
 * the choices were already shown. */
static void linenoiseBeep(struct linenoiseState *ls)
{
    ln_write("\x07", 1);
}

/* ============================== Completion ================================ */

/* Free a list of completion option populated by linenoiseAddCompletion(). */
static void freeCompletions(linenoiseCompletions *lc)
{
    size_t i;
    for (i = 0; i < lc->len; i++) {
        console_free(lc->cvec[i]);
    }

    if (lc->cvec != NULL) {
        console_free(lc->cvec);
    }
}

/* This is an helper function for linenoiseEdit() and is called when the
 * user types the <tab> key in order to complete the string currently in the
 * input.
 *
 * The state of the editing is encapsulated into the pointed linenoiseState
 * structure as described in the structure definition. */
static int completeLine(struct linenoiseState *ls)
{
    linenoiseCompletions lc = {0, NULL};
    int nread;
    int nwritten;
    char c = 0;

    ls->completionCallback(ls->buf, &lc);
    if (lc.len == 0) {
        linenoiseBeep(ls);
    }
    else {
        size_t stop = 0;
        size_t i = 0;

        while (!stop) {
            /* Show completion or original buffer */
            if (i < lc.len) {
                struct linenoiseState saved = *ls;

                ls->len = ls->pos = (int) strlen(lc.cvec[i]);
                ls->buf = lc.cvec[i];
                refreshLine(ls);
                ls->len = saved.len;
                ls->pos = saved.pos;
                ls->buf = saved.buf;
            }
            else {
                refreshLine(ls);
            }

            nread = ln_read(&c, 1);
            if (nread <= 0) {
                freeCompletions(&lc);
                return -1;
            }

            switch (c) {
                case TAB: /* tab */
                    i = (i + 1) % (lc.len + 1);
                    if (i == lc.len) linenoiseBeep(ls);
                    break;
                case ESC: /* escape */
                    /* Re-show original buffer */
                    if (i < lc.len) refreshLine(ls);
                    stop = 1;
                    break;
                default:
                    /* Update buffer and return */
                    if (i < lc.len) {
                        nwritten = snprintf(ls->buf, ls->buflen, "%s", lc.cvec[i]);
                        ls->len = ls->pos = nwritten;
                    }
                    stop = 1;
                    break;
            }
        }
    }

    freeCompletions(&lc);
    return c; /* Return last read character */
}

/* This function is used by the callback function registered by the user
 * in order to add completion options given the input string when the
 * user typed <tab>. See the example.c source code for a very easy to
 * understand example. */
void consLnAddCompletion(linenoiseCompletions *lc, const char *text)
{
    size_t len = strlen(text);
    char *copy;
    char **cvec;

    copy = console_calloc(len + 1, 1);
    if (copy == NULL) return;
    memcpy(copy, text, len + 1);
    cvec = console_realloc(lc->cvec, sizeof(char *) * (lc->len), sizeof(char *) * (lc->len + 1));
    if (cvec == NULL) {
        console_free(copy);
        return;
    }
    lc->cvec = cvec;
    lc->cvec[lc->len++] = copy;
}

/* =========================== Line editing ================================= */

/* We define a very simple "append buffer" structure, that is an heap
 * allocated string where we can append to. This is useful in order to
 * write all the escape sequences in a buffer and flush them to the standard
 * output in a single call, to avoid flickering effects. */
struct abuf {
    char *b;
    int len;
};

static void abInit(struct abuf *ab)
{
    ab->b = NULL;
    ab->len = 0;
}

static void abAppend(struct abuf *ab, const char *s, size_t len)
{
    char *new = console_realloc(ab->b, ab->len, ab->len + len);
    if (new == NULL) return;
    memcpy(new + ab->len, s, len);
    ab->b = new;
    ab->len += len;
}

static void abFree(struct abuf *ab)
{
    console_free(ab->b);
}

/* Helper of refreshSingleLine() and refreshMultiLine() to show hints
 * to the right of the prompt. */
static void refreshShowHints(struct abuf *ab, struct linenoiseState *ls, int plen)
{
    char seq[64];
    if (ls->hintsCallback && plen + ls->len < ls->cols) {
        int color = -1;
        int bold = 0;
        char *hint = ls->hintsCallback(ls->buf, &color, &bold);
        if (hint) {
            size_t hintlen = strlen(hint);
            int hintmaxlen = ls->cols - (plen + ls->len);
            if ((int)hintlen > hintmaxlen) hintlen = hintmaxlen;
            if (bold == 1 && color == -1) color = 37;
            if (color != -1 || bold != 0)
                snprintf(seq, 64, "\033[%d;%d;49m", bold, color);
            abAppend(ab, seq, strlen(seq));
            abAppend(ab, hint, hintlen);
            if (color != -1 || bold != 0)
                abAppend(ab, "\033[0m", 4);
            /* Call the function to free the hint returned. */
            if (ls->freeHintsCallback) ls->freeHintsCallback(hint);
        }
    }
}

/* Single line low level line refresh.
 *
 * Rewrite the currently edited line accordingly to the buffer content,
 * cursor position, and number of columns of the terminal. */
static void refreshSingleLine(struct linenoiseState *ls)
{
    char seq[64];
    size_t plen = ls->plen;
    char *buf = ls->buf;
    size_t len = ls->len;
    size_t pos = ls->pos;
    struct abuf ab;

    while (((int)(plen + pos)) >= ls->cols) {
        buf++;
        len--;
        pos--;
    }
    while (((int)(plen + len)) > ls->cols) {
        len--;
    }

    abInit(&ab);
    /* Cursor to left edge */
    snprintf(seq, 64, "\r");
    abAppend(&ab, seq, strlen(seq));
    /* Write the prompt and the current buffer content */
    abAppend(&ab, ls->prompt, strlen(ls->prompt));
    abAppend(&ab, buf, len);
    /* Show hits if any. */
    refreshShowHints(&ab, ls, plen);
    /* Erase to right */
    snprintf(seq, 64, "\x1b[0K");
    abAppend(&ab, seq, strlen(seq));
    /* Move cursor to original position. */
    snprintf(seq, 64, "\r\x1b[%dC", (int) (pos + plen));
    abAppend(&ab, seq, strlen(seq));
    if (ln_write(ab.b, ab.len) == -1) {} /* Can't recover from write error. */
    abFree(&ab);
}

/* Multi line low level line refresh.
 *
 * Rewrite the currently edited line accordingly to the buffer content,
 * cursor position, and number of columns of the terminal. */
static void refreshMultiLine(struct linenoiseState *ls)
{
    char seq[64];
    int plen = ls->plen;
    int rows = (plen + ls->len + ls->cols - 1) / ls->cols; /* rows used by current buf. */
    int rpos = (plen + ls->oldpos + ls->cols) / ls->cols; /* cursor relative row. */
    int rpos2; /* rpos after refresh. */
    int col; /* colum position, zero-based. */
    int old_rows = ls->maxrows;
    int j;
    struct abuf ab;

    /* Update maxrows if needed. */
    if (rows > (int) ls->maxrows) ls->maxrows = rows;

    /* First step: clear all the lines used before. To do so start by
     * going to the last row. */
    abInit(&ab);
    if (old_rows - rpos > 0) {

        snprintf(seq, 64, "\x1b[%dB", old_rows - rpos);
        abAppend(&ab, seq, strlen(seq));
    }

    /* Now for every row clear it, go up. */
    for (j = 0; j < old_rows - 1; j++) {

        snprintf(seq, 64, "\r\x1b[0K\x1b[1A");
        abAppend(&ab, seq, strlen(seq));
    }

    /* Clean the top line. */

    snprintf(seq, 64, "\r\x1b[0K");
    abAppend(&ab, seq, strlen(seq));

    /* Write the prompt and the current buffer content */
    abAppend(&ab, ls->prompt, strlen(ls->prompt));
    abAppend(&ab, ls->buf, ls->len);

    /* Show hits if any. */
    refreshShowHints(&ab, ls, plen);

    /* If we are at the very end of the screen with our prompt, we need to
     * emit a newline and move the prompt to the first column. */
    if (ls->pos &&
        ls->pos == ls->len &&
        (ls->pos + plen) % ls->cols == 0) {

        abAppend(&ab, "\n", 1);
        snprintf(seq, 64, "\r");
        abAppend(&ab, seq, strlen(seq));
        rows++;
        if (rows > (int) ls->maxrows) ls->maxrows = rows;
    }

    /* Move cursor to right position. */
    rpos2 = (plen + ls->pos + ls->cols) / ls->cols; /* current cursor relative row. */


    /* Go up till we reach the expected positon. */
    if (rows - rpos2 > 0) {

        snprintf(seq, 64, "\x1b[%dA", rows - rpos2);
        abAppend(&ab, seq, strlen(seq));
    }

    /* Set column. */
    col = (plen + (int) ls->pos) % (int) ls->cols;

    if (col)
        snprintf(seq, 64, "\r\x1b[%dC", col);
    else
        snprintf(seq, 64, "\r");
    abAppend(&ab, seq, strlen(seq));


    ls->oldpos = ls->pos;

    if (ln_write(ab.b, ab.len) == -1) {} /* Can't recover from write error. */
    abFree(&ab);
}

/* Calls the two low level functions refreshSingleLine() or
 * refreshMultiLine() according to the selected mode. */
static void refreshLine(struct linenoiseState *ls)
{
    if (ls->mlmode)
        refreshMultiLine(ls);
    else
        refreshSingleLine(ls);
}

/* Insert the character 'c' at cursor current position.
 *
 * On error writing to the terminal -1 is returned, otherwise 0. */
static int linenoiseEditInsert(struct linenoiseState *ls, char c)
{
    if (ls->len < (int)ls->buflen) {
        if (ls->len == ls->pos) {
            ls->buf[ls->pos] = c;
            ls->pos++;
            ls->len++;
            ls->buf[ls->len] = '\0';
            if ((!ls->mlmode && (int)(ls->plen + ls->len) < ls->cols && !ls->hintsCallback)) {
                /* Avoid a full update of the line in the
                 * trivial case. */
                if (ln_write(&c, 1) == -1) return -1;
            }
            else {
                refreshLine(ls);
            }
        }
        else {
            memmove(ls->buf + ls->pos + 1, ls->buf + ls->pos, ls->len - ls->pos);
            ls->buf[ls->pos] = c;
            ls->len++;
            ls->pos++;
            ls->buf[ls->len] = '\0';
            refreshLine(ls);
        }
    }
    return 0;
}

/* Move cursor on the left. */
static void linenoiseEditMoveLeft(struct linenoiseState *ls)
{
    if (ls->pos > 0) {
        ls->pos--;
        refreshLine(ls);
    }
}

/* Move cursor on the right. */
static void linenoiseEditMoveRight(struct linenoiseState *ls)
{
    if (ls->pos != ls->len) {
        ls->pos++;
        refreshLine(ls);
    }
}

/* Move cursor to the start of the line. */
static void linenoiseEditMoveHome(struct linenoiseState *ls)
{
    if (ls->pos != 0) {
        ls->pos = 0;
        refreshLine(ls);
    }
}

/* Move cursor to the end of the line. */
static void linenoiseEditMoveEnd(struct linenoiseState *ls)
{
    if (ls->pos != ls->len) {
        ls->pos = ls->len;
        refreshLine(ls);
    }
}

/* Substitute the currently edited line with the next or previous history
 * entry as specified by 'dir'. */
enum linenoise_history_dir {
    LINENOISE_HISTORY_NEXT,
    LINENOISE_HISTORY_PREV,
};

static void linenoiseEditHistoryNext(struct linenoiseState *ls, enum linenoise_history_dir dir)
{
    if (ls->history_len > 1) {
        /* Update the current history entry before to
         * overwrite it with the next one. */
        console_free(ls->history[ls->history_len - 1 - ls->history_index]);
        ls->history[ls->history_len - 1 - ls->history_index] = console_strdup(ls->buf);
        /* Show the new entry */
        ls->history_index += (dir == LINENOISE_HISTORY_PREV) ? 1 : -1;
        if (ls->history_index < 0) {
            ls->history_index = 0;
            return;
        }
        else if (ls->history_index >= ls->history_len) {
            ls->history_index = ls->history_len - 1;
            return;
        }
        strncpy(ls->buf, ls->history[ls->history_len - 1 - ls->history_index], ls->buflen);
        ls->buf[ls->buflen - 1] = '\0';
        ls->len = ls->pos = (int) strlen(ls->buf);
        refreshLine(ls);
    }
}

/* Delete the character at the right of the cursor without altering the cursor
 * position. Basically this is what happens with the "Delete" keyboard key. */
static void linenoiseEditDelete(struct linenoiseState *ls)
{
    if (ls->len > 0 && ls->pos < ls->len) {
        memmove(ls->buf + ls->pos, ls->buf + ls->pos + 1, ls->len - ls->pos - 1);
        ls->len--;
        ls->buf[ls->len] = '\0';
        refreshLine(ls);
    }
}

/* Backspace implementation. */
static void linenoiseEditBackspace(struct linenoiseState *ls)
{
    if (ls->pos > 0 && ls->len > 0) {
        memmove(ls->buf + ls->pos - 1, ls->buf + ls->pos, ls->len - ls->pos);
        ls->pos--;
        ls->len--;
        ls->buf[ls->len] = '\0';
        refreshLine(ls);
    }
}

/* Delete the previosu word, maintaining the cursor at the start of the
 * current word. */
static void linenoiseEditDeletePrevWord(struct linenoiseState *ls)
{
    size_t old_pos = ls->pos;
    size_t diff;

    while (ls->pos > 0 && ls->buf[ls->pos - 1] == ' ')
        ls->pos--;
    while (ls->pos > 0 && ls->buf[ls->pos - 1] != ' ')
        ls->pos--;
    diff = old_pos - ls->pos;
    memmove(ls->buf + ls->pos, ls->buf + old_pos, ls->len - old_pos + 1);
    ls->len -= diff;
    refreshLine(ls);
}

/** Get line's length, skipping over ANSI codes */
static uint32_t getAnsiLen(const char *prompt)
{
    enum {
        GAL_BASE,
        GAL_ESC,
        GAL_DROP_NEXT,
        GAL_DROP_UNTIL_ALPHA,
        GAL_DROP_UNTIL_X,
    } state = GAL_BASE;

    char c;
    char x = 0;
    uint32_t count = 0;
    while ((c = *prompt++) != 0) {
        switch (state) {
            default:
            case GAL_BASE:
                if (c == 27) {
                    state = GAL_ESC;
                }
                else {
                    count++;
                }
                break;
            case GAL_ESC:
                switch (c) {
                    case '[':
                        state = GAL_DROP_UNTIL_ALPHA;
                        break;
                    case '#':
                        state = GAL_DROP_NEXT;
                        break;
                    case 'K':
                        x = 'r';
                        state = GAL_DROP_UNTIL_X;
                        break;
                    case '(':
                    case ')':
                        state = GAL_DROP_NEXT;
                        break;
                    default:
                        state = GAL_BASE;
                }
                break;
            case GAL_DROP_NEXT:
                state = GAL_BASE;
                break;
            case GAL_DROP_UNTIL_ALPHA:
                if ((c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z')) {
                    state = GAL_BASE;
                }
                break;
            case GAL_DROP_UNTIL_X:
                if (c == x) {
                    state = GAL_BASE;
                }
                break;
        }
    }

    return count;
}

/* This function is the core of the line editing capability of linenoise.
 * It expects 'fd' to be already in "raw mode" so that every key pressed
 * will be returned ASAP to read().
 *
 * The resulting string is put into 'buf' when the user type enter, or
 * when ctrl+d is typed.
 *
 * The function returns the length of the current buffer. */
static int linenoiseEdit(struct linenoiseState *ls)
{
    if (!ls->buf) {
        console_internal_error_print("LN ed no buf");
        return -1;
    }

    ls->plen = getAnsiLen(ls->prompt);
    ls->oldpos = ls->pos = 0;
    ls->len = 0;
    ls->cols = getColumns();
    ls->maxrows = 0;
    ls->history_index = 0;

    /* Buffer starts empty. */
    ls->buf[0] = '\0';

    /* The latest history entry is always our current buffer, that
     * initially is just an empty string. */
    consLnHistoryAdd(ls, "");

    if (ln_writez(ls->prompt) == -1) {
        console_internal_error_print("LN ed prompt print err");
        return -1;
    }

    while (1) {
        char c = 0;
        int nread;
        char seq[3];

        nread = ln_read(&c, 1);
        if (nread <= 0) {
            console_internal_error_print("LN ed read err");
            return ls->len; // read error
        }

        if (c == 0) continue; // discard null bytes

        /* Only autocomplete when the callback is set. It returns < 0 when
         * there was an error reading from fd. Otherwise it will return the
         * character that should be handled next. */
        if (c == TAB && ls->completionCallback != NULL) {
            int c2 = completeLine(ls);
            /* Return on errors */
            if (c2 < 0) return ls->len;
            /* Read next character when 0 */
            if (c2 == 0) continue;
            c = (char) c2;
        }

        switch (c) {
            case ENTER:    /* enter */
            case RETURN:    /* \n */
                ls->history_len--;
                console_free(ls->history[ls->history_len]);
                if (ls->mlmode) linenoiseEditMoveEnd(ls);
                if (ls->hintsCallback) {
                    /* Force a refresh without hints to leave the previous
                     * line as the user typed it after a newline. */
                    linenoiseHintsCallback *hc = ls->hintsCallback;
                    ls->hintsCallback = NULL;
                    refreshLine(ls);
                    ls->hintsCallback = hc;
                }
                return (int) ls->len;
            case CTRL_C:     /* ctrl-c */
                if (ls->len == 0 && ls->allowCtrlDExit) {
                    errno = EAGAIN;
                    //console_internal_error_print("LN Ctrl+C, exit");
                    return -1;
                } else {
                    // Same as Ctrl+U
                    ls->buf[0] = '\0';
                    ls->pos = ls->len = 0;
                    refreshLine(ls);
                }
                break;
            case BACKSPACE:   /* backspace */
            case 8:     /* ctrl-h */
                linenoiseEditBackspace(ls);
                break;
            case CTRL_D:     /* ctrl-d, remove char at right of cursor, or if the
                            line is empty, act as end-of-file. */
                if (ls->len > 0) {
                    linenoiseEditDelete(ls);
                }
                else {
                    if (ls->allowCtrlDExit) {
                        ls->history_len--;
                        console_free(ls->history[ls->history_len]);
                        //console_internal_error_print("LN Ctrl+D, exit");
                        return -1;
                    }
                }
                break;
            case CTRL_T:    /* ctrl-t, swaps current character with previous. */
                if (ls->pos > 0 && ls->pos < ls->len) {
                    char aux = ls->buf[ls->pos - 1];
                    ls->buf[ls->pos - 1] = ls->buf[ls->pos];
                    ls->buf[ls->pos] = aux;
                    if (ls->pos != ls->len - 1) ls->pos++;
                    refreshLine(ls);
                }
                break;
            case CTRL_B:     /* ctrl-b */
                linenoiseEditMoveLeft(ls);
                break;
            case CTRL_F:     /* ctrl-f */
                linenoiseEditMoveRight(ls);
                break;
            case CTRL_P:    /* ctrl-p */
                linenoiseEditHistoryNext(ls, LINENOISE_HISTORY_PREV);
                break;
            case CTRL_N:    /* ctrl-n */
                linenoiseEditHistoryNext(ls, LINENOISE_HISTORY_NEXT);
                break;
            case ESC:    /* escape sequence */
                /* Read the next two bytes representing the escape sequence. */
                if (ln_read(seq, 2) < 2) break;

                /* ESC [ sequences. */
                if (seq[0] == '[') {
                    if (seq[1] >= '0' && seq[1] <= '9') {
                        /* Extended escape, read additional byte. */
                        if (ln_read(seq + 2, 1) == -1) break;
                        if (seq[2] == '~') {
                            switch (seq[1]) {
                                case '3': /* Delete key. */
                                    linenoiseEditDelete(ls);
                                    break;
                            }
                        }
                    }
                    else {
                        switch (seq[1]) {
                            case 'A': /* Up */
                                linenoiseEditHistoryNext(ls, LINENOISE_HISTORY_PREV);
                                break;
                            case 'B': /* Down */
                                linenoiseEditHistoryNext(ls, LINENOISE_HISTORY_NEXT);
                                break;
                            case 'C': /* Right */
                                linenoiseEditMoveRight(ls);
                                break;
                            case 'D': /* Left */
                                linenoiseEditMoveLeft(ls);
                                break;
                            case 'H': /* Home */
                                linenoiseEditMoveHome(ls);
                                break;
                            case 'F': /* End*/
                                linenoiseEditMoveEnd(ls);
                                break;
                        }
                    }
                }

                    /* ESC O sequences. */
                else if (seq[0] == 'O') {
                    switch (seq[1]) {
                        case 'H': /* Home */
                            linenoiseEditMoveHome(ls);
                            break;
                        case 'F': /* End*/
                            linenoiseEditMoveEnd(ls);
                            break;
                    }
                }
                break;
            default:
                if (linenoiseEditInsert(ls, c)) return -1;
                break;
            case CTRL_U: /* Ctrl+u, delete the whole line. */
                ls->buf[0] = '\0';
                ls->pos = ls->len = 0;
                refreshLine(ls);
                break;
            case CTRL_K: /* Ctrl+k, delete from current to end of line. */
                ls->buf[ls->pos] = '\0';
                ls->len = ls->pos;
                refreshLine(ls);
                break;
            case CTRL_A: /* Ctrl+a, go to the start of the line */
                linenoiseEditMoveHome(ls);
                break;
            case CTRL_E: /* ctrl+e, go to the end of the line */
                linenoiseEditMoveEnd(ls);
                break;
            case CTRL_L: /* ctrl+l, clear screen */
                consLnClearScreen(ls);
                refreshLine(ls);
                break;
            case CTRL_W: /* ctrl+w, delete previous word */
                linenoiseEditDeletePrevWord(ls);
                break;
        }
    }
}

static int linenoiseRaw(struct linenoiseState *ls)
{
    int count;

    if (ls->buflen == 0) {
        errno = EINVAL;
        console_internal_error_print("LN raw buflen 0");
        return -1;
    }

    count = linenoiseEdit(ls);

    if (count >= 0) ln_write("\r\n", 2);

    return count;
}

static bool last_line_ended_with_0D = false;

static int linenoiseDumb(struct linenoiseState *ls)
{
    /* dumb terminal, fall back to fgets */
    ln_writez(ls->prompt);
    int count = 0;
    char c = 0;
    while (count < (int)ls->buflen) {
        int num = ln_read(&c, 1);
        if (num == 0) break;
        if (c == 0) continue;

        int shouldprint = 1;
        if (c == '\n' || c == '\r') {
            // prevent CRLF acting as two newlines
            if (c == '\n' && last_line_ended_with_0D) {
                last_line_ended_with_0D = false;
                continue;
            }

            if (c == '\r') {
                last_line_ended_with_0D = true;
            }
            break;
        }
        else if (c >= 0x1c && c <= 0x1f) {
            shouldprint = 0; /* consume arrow keys */
        }
        else if (c == BACKSPACE || c == 0x8) {
            if (count > 0) {
                ls->buf[count - 1] = 0;
                count--;
                if (ls->echomode) ln_write("\x08 ", 2); // second x08 is printed by the fputc below
            }
            else {
                shouldprint = 0;
            }
        }
        else {
            ls->buf[count] = c;
            ++count;
        }

        if (ls->echomode && shouldprint) {
            ln_write(&c, 1); /* echo */
        }
    }

    ls->buf[count] = 0;

    ln_write("\r\n", 2);
    return count;
}

static void sanitize(char *src)
{
    char *dst = src;
    for (int c = *src; c != 0; src++, c = *src) {
        if (isprint(c)) {
            *dst = (char) c;
            ++dst;
        }
    }
    *dst = 0;
}

/* The high level function that is the main API of the linenoise library. */
int consLnReadLine(struct linenoiseState *ls)
{
    int count = 0;
    if (!ls->dumbmode) {
        count = linenoiseRaw(ls);
    }
    else {
        count = linenoiseDumb(ls);
    }

    if (count > 0) {
        sanitize(ls->buf);
        count = (int) strlen(ls->buf);
    }

    return count;
}

/* ================================ History ================================= */

/** Free history buffer for instance */
void consLnHistoryFree(struct linenoiseState *ls)
{
    if (ls->history) {
        for (int j = 0; j < ls->history_len; j++) {
            console_free(ls->history[j]);
        }
        console_free(ls->history);
    }
    ls->history = NULL;
}

/* This is the API call to add a new entry in the linenoise history.
 * It uses a fixed array of char pointers that are shifted (memmoved)
 * when the history max length is reached in order to remove the older
 * entry and make room for the new one, so it is not exactly suitable for huge
 * histories, but will work well for a few hundred of entries.
 *
 * Using a circular buffer is smarter, but a bit more complex to handle. */
int consLnHistoryAdd(struct linenoiseState *ls, const char *line)
{
    char *linecopy;

    if (ls->history_max_len == 0) return 0;

    /* Initialization on first call. */
    if (ls->history == NULL) {
        ls->history = console_calloc(sizeof(char *) * ls->history_max_len, 1);
        if (ls->history == NULL) return 0;
        memset(ls->history, 0, (sizeof(char *) * ls->history_max_len));
    }

    /* Don't add duplicated lines. */
    if (ls->history_len && !strcmp(ls->history[ls->history_len - 1], line)) return 0;

    /* Add an heap allocated copy of the line in the history.
     * If we reached the max length, remove the older line. */
    linecopy = console_strdup(line);
    if (!linecopy) return 0;
    if (ls->history_len == ls->history_max_len) {
        console_free(ls->history[0]);
        memmove(ls->history, ls->history + 1, sizeof(char *) * (ls->history_max_len - 1));
        ls->history_len--;
    }
    ls->history[ls->history_len] = linecopy;
    ls->history_len++;
    return 1;
}

/* Set the maximum length for the history. This function can be called even
 * if there is already some history, the function will make sure to retain
 * just the latest 'len' elements if the new history length value is smaller
 * than the amount of items already inside the history. */
int consLnHistorySetMaxLen(struct linenoiseState *ls, int len)
{
    char **new;

    if (len < 1) return 0;
    if (ls->history) {
        int tocopy = ls->history_len;

        new = console_calloc(sizeof(char *) * len, 1);
        if (new == NULL) return 0;

        /* If we can't copy everything, free the elements we'll not use. */
        if (len < tocopy) {
            int j;

            for (j = 0; j < tocopy - len; j++) console_free(ls->history[j]);
            tocopy = len;
        }
        memset(new, 0, sizeof(char *) * len);
        memcpy(new, ls->history + (ls->history_len - tocopy), sizeof(char *) * tocopy);
        console_free(ls->history);
        ls->history = new;
    }
    ls->history_max_len = len;
    if (ls->history_len > ls->history_max_len)
        ls->history_len = ls->history_max_len;
    return 1;
}

#if CONSOLE_FILE_SUPPORT
/* Save the history in the specified file. On success 0 is returned
 * otherwise -1 is returned. */
int consLnHistorySave(struct linenoiseState *ls, const char *filename)
{
    FILE *fp;
    int j;

    fp = fopen(filename, "w");
    if (fp == NULL) return -1;
    for (j = 0; j < ls->history_len; j++)
        fprintf(fp, "%s\n", ls->history[j]);
    fclose(fp);
    return 0;
}

/* Load the history from the specified file. If the file does not exist
 * zero is returned and no operation is performed.
 *
 * If the file exists and the operation succeeded 0 is returned, otherwise
 * on error -1 is returned. */
int consLnHistoryLoad(struct linenoiseState *ls, const char *filename)
{
    FILE *fp = fopen(filename, "r");
    char buf[LINENOISE_HISTORY_MAX_LINE];

    if (fp == NULL) return -1;

    // Discard old history, if any
    consLnHistoryFree(ls);

    while (fgets(buf, LINENOISE_HISTORY_MAX_LINE, fp) != NULL) {
        char *p;

        p = strchr(buf, '\r');
        if (!p) p = strchr(buf, '\n');
        if (p) *p = '\0';
        consLnHistoryAdd(ls, buf);
    }
    fclose(fp);
    return 0;
}
#endif