/*
 * gui-history.c - memorize commands or text for buffers (used by all GUI)
 *
 * Copyright (C) 2003-2024 Sébastien Helleu <flashcode@flashtux.org>
 * Copyright (C) 2005 Emmanuel Bouthenot <kolter@openics.org>
 *
 * This file is part of WeeChat, the extensible chat client.
 *
 * WeeChat is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 3 of the License, or
 * (at your option) any later version.
 *
 * WeeChat is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with WeeChat.  If not, see <https://www.gnu.org/licenses/>.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <stdlib.h>
#include <stdio.h>
#include <stddef.h>
#include <string.h>

#include "../core/weechat.h"
#include "../core/core-config.h"
#include "../core/core-hashtable.h"
#include "../core/core-hdata.h"
#include "../core/core-hook.h"
#include "../core/core-infolist.h"
#include "../core/core-string.h"
#include "../plugins/plugin.h"
#include "gui-history.h"
#include "gui-buffer.h"
#include "gui-input.h"


struct t_gui_history *gui_history = NULL;
struct t_gui_history *last_gui_history = NULL;
struct t_gui_history *gui_history_ptr = NULL;
int num_gui_history = 0;


/*
 * Removes oldest history entry in a buffer.
 */

void
gui_history_buffer_remove_oldest (struct t_gui_buffer *buffer)
{
    struct t_gui_history *ptr_history;

    if (buffer->text_search_ptr_history == buffer->last_history)
    {
        buffer->text_search_ptr_history = NULL;
        buffer->text_search_found = 0;
        gui_input_search_signal (buffer);
    }

    ptr_history = buffer->last_history->prev_history;
    if (buffer->ptr_history == buffer->last_history)
        buffer->ptr_history = ptr_history;
    ((buffer->last_history)->prev_history)->next_history = NULL;
    free (buffer->last_history->text);
    free (buffer->last_history);
    buffer->last_history = ptr_history;

    buffer->num_history--;
}

/*
 * Adds a text/command to buffer's history.
 */

void
gui_history_buffer_add (struct t_gui_buffer *buffer, const char *string)
{
    struct t_gui_history *new_history;

    if (!string)
        return;

    if (buffer->history && buffer->history->text
        && (strcmp (buffer->history->text, string) == 0))
        return;

    new_history = malloc (sizeof (*new_history));
    if (new_history)
    {
        new_history->text = strdup (string);
        if (buffer->history)
            buffer->history->prev_history = new_history;
        else
            buffer->last_history = new_history;
        new_history->next_history = buffer->history;
        new_history->prev_history = NULL;
        buffer->history = new_history;
        buffer->num_history++;

        /* remove one command if necessary */
        if ((CONFIG_INTEGER(config_history_max_commands) > 0)
            && (buffer->num_history > CONFIG_INTEGER(config_history_max_commands)))
        {
            gui_history_buffer_remove_oldest (buffer);
        }
    }
}

/*
 * Removes oldest global history entry.
 */

void
gui_history_global_remove_oldest ()
{
    struct t_gui_buffer *ptr_buffer;
    struct t_gui_history *ptr_history;

    /* ensure no buffer is using the last global history entry */
    for (ptr_buffer = gui_buffers; ptr_buffer;
         ptr_buffer = ptr_buffer->next_buffer)
    {
        if (ptr_buffer->text_search_ptr_history == last_gui_history)
        {
            ptr_buffer->text_search_ptr_history = NULL;
            ptr_buffer->text_search_found = 0;
            gui_input_search_signal (ptr_buffer);
        }
    }

    ptr_history = last_gui_history->prev_history;
    if (gui_history_ptr == last_gui_history)
        gui_history_ptr = ptr_history;
    (last_gui_history->prev_history)->next_history = NULL;
    free (last_gui_history->text);
    free (last_gui_history);
    last_gui_history = ptr_history;

    num_gui_history--;
}

/*
 * Adds a text/command to global history.
 */

void
gui_history_global_add (const char *string)
{
    struct t_gui_history *new_history;

    if (!string)
        return;

    if (gui_history && (strcmp (gui_history->text, string) == 0))
        return;

    new_history = malloc (sizeof (*new_history));
    if (new_history)
    {
        new_history->text = strdup (string);
        if (gui_history)
            gui_history->prev_history = new_history;
        else
            last_gui_history = new_history;
        new_history->next_history = gui_history;
        new_history->prev_history = NULL;
        gui_history = new_history;
        num_gui_history++;

        /* remove one command if necessary */
        if ((CONFIG_INTEGER(config_history_max_commands) > 0)
            && (num_gui_history > CONFIG_INTEGER(config_history_max_commands)))
        {
            gui_history_global_remove_oldest ();
        }
    }
}

/*
 * Adds a text/command to buffer's history + global history.
 */

void
gui_history_add (struct t_gui_buffer *buffer, const char *string)
{
    char *string2, str_buffer[128];

    snprintf (str_buffer, sizeof (str_buffer), "%p", buffer);
    string2 = hook_modifier_exec (NULL, "history_add", str_buffer, string);

    /*
     * if message was NOT dropped by modifier, then we add it to buffer and
     * global history
     */
    if (!string2 || string2[0])
    {
        gui_history_buffer_add (buffer, (string2) ? string2 : string);
        gui_history_global_add ((string2) ? string2 : string);
    }

    free (string2);
}

/*
 * Searches for text in a history entry.
 *
 * Returns:
 *   1: text found in line
 *   0: text not found in line
 */

int
gui_history_search_text (struct t_gui_buffer *buffer,
                         struct t_gui_history *history)
{
    int rc;

    if (!history || !history->text
        || !buffer->input_buffer || !buffer->input_buffer[0])
    {
        return 0;
    }

    rc = 0;

    if (buffer->text_search_regex)
    {
        if (buffer->text_search_regex_compiled
            && (regexec (buffer->text_search_regex_compiled,
                         history->text, 0, NULL, 0) == 0))
        {
            rc = 1;
        }
    }
    else if ((buffer->text_search_exact
              && (strstr (history->text, buffer->input_buffer)))
             || (!buffer->text_search_exact
                 && (string_strcasestr (history->text, buffer->input_buffer))))
    {
        rc = 1;
    }

    return rc;
}

/*
 * Searches in history using string in buffer input.
 *
 * Returns:
 *   1: an history was found
 *   0: text not found
 */

int
gui_history_search (struct t_gui_buffer *buffer,
                    struct t_gui_history *history)
{
    struct t_gui_history *ptr_history;
    int direction;

    if (!buffer->input_buffer || !buffer->input_buffer[0])
        return 0;

    direction = (buffer->text_search_direction == GUI_BUFFER_SEARCH_DIR_BACKWARD) ?
        1 : -1;

    if (buffer->text_search_ptr_history)
    {
        ptr_history = (direction > 0) ?
            buffer->text_search_ptr_history->next_history :
            buffer->text_search_ptr_history->prev_history;
    }
    else
    {
        ptr_history = history;
    }

    while (ptr_history)
    {
        if (gui_history_search_text (buffer, ptr_history))
        {
            buffer->text_search_ptr_history = ptr_history;
            return 1;
        }
        ptr_history = (direction > 0) ?
            ptr_history->next_history : ptr_history->prev_history;
    }
    return 0;
}

/*
 * Frees global history.
 */

void
gui_history_global_free ()
{
    struct t_gui_history *ptr_history;

    while (gui_history)
    {
        ptr_history = gui_history->next_history;
        free (gui_history->text);
        free (gui_history);
        gui_history = ptr_history;
    }
    gui_history = NULL;
    last_gui_history = NULL;
    gui_history_ptr = NULL;
    num_gui_history = 0;
}


/*
 * Frees history for a buffer.
 */

void
gui_history_buffer_free (struct t_gui_buffer *buffer)
{
    struct t_gui_history *ptr_history;

    if (!buffer)
        return;

    while (buffer->history)
    {
        ptr_history = buffer->history->next_history;
        free (buffer->history->text);
        free (buffer->history);
        buffer->history = ptr_history;
    }
    buffer->history = NULL;
    buffer->last_history = NULL;
    buffer->ptr_history = NULL;
    buffer->num_history = 0;
}

/*
 * Callback for updating history.
 */

int
gui_history_hdata_history_update_cb (void *data,
                                     struct t_hdata *hdata,
                                     void *pointer,
                                     struct t_hashtable *hashtable)
{
    struct t_gui_history *ptr_history;
    struct t_gui_buffer *ptr_buffer;
    const char *text, *buffer;
    unsigned long value;
    int rc;

    /* make C compiler happy */
    (void) data;
    (void) hdata;

    rc = 0;

    text = hashtable_get (hashtable, "text");
    if (!text)
        return rc;

    if (pointer)
    {
        /* update history */
        ptr_history = (struct t_gui_history *)pointer;
        free (ptr_history->text);
        ptr_history->text = strdup (text);
    }
    else
    {
        /* create new entry in history */
        ptr_buffer = NULL;
        if (hashtable_has_key (hashtable, "buffer"))
        {
            buffer = hashtable_get (hashtable, "buffer");
            if (buffer)
            {
                rc = sscanf (buffer, "%lx", &value);
                if ((rc != EOF) && (rc != 0))
                    ptr_buffer = (struct t_gui_buffer *)value;
            }
        }
        if (ptr_buffer)
            gui_history_add (ptr_buffer, text);
        else
            gui_history_global_add (text);
    }

    return rc;
}

/*
 * Returns hdata for history.
 */

struct t_hdata *
gui_history_hdata_history_cb (const void *pointer, void *data,
                              const char *hdata_name)
{
    struct t_hdata *hdata;

    /* make C compiler happy */
    (void) pointer;
    (void) data;

    hdata = hdata_new (NULL, hdata_name, "prev_history", "next_history",
                       1, 1, &gui_history_hdata_history_update_cb, NULL);
    if (hdata)
    {
        HDATA_VAR(struct t_gui_history, text, STRING, 0, NULL, NULL);
        HDATA_VAR(struct t_gui_history, prev_history, POINTER, 0, NULL, hdata_name);
        HDATA_VAR(struct t_gui_history, next_history, POINTER, 0, NULL, hdata_name);
        HDATA_LIST(gui_history, WEECHAT_HDATA_LIST_CHECK_POINTERS);
        HDATA_LIST(last_gui_history, 0);
    }
    return hdata;
}

/*
 * Adds history in an infolist.
 *
 * Returns:
 *   1: OK
 *   0: error
 */

int
gui_history_add_to_infolist (struct t_infolist *infolist,
                             struct t_gui_history *history)
{
    struct t_infolist_item *ptr_item;

    if (!infolist || !history)
        return 0;

    ptr_item = infolist_new_item (infolist);
    if (!ptr_item)
        return 0;

    if (!infolist_new_var_string (ptr_item, "text", history->text))
        return 0;

    return 1;
}