/*
 * inputwin.c
 *
 * Copyright (C) 2012 - 2014 James Booth <boothj5@gmail.com>
 *
 * This file is part of Profanity.
 *
 * Profanity 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.
 *
 * Profanity 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 Profanity.  If not, see <http://www.gnu.org/licenses/>.
 *
 * In addition, as a special exception, the copyright holders give permission to
 * link the code of portions of this program with the OpenSSL library under
 * certain conditions as described in each individual source file, and
 * distribute linked combinations including the two.
 *
 * You must obey the GNU General Public License in all respects for all of the
 * code used other than OpenSSL. If you modify file(s) with this exception, you
 * may extend this exception to your version of the file(s), but you are not
 * obligated to do so. If you do not wish to do so, delete this exception
 * statement from your version. If you delete this exception statement from all
 * source files in the program, then also delete it here.
 *
 */

#define _XOPEN_SOURCE_EXTENDED
#include "config.h"

#include <stdlib.h>
#include <string.h>
#include <wchar.h>

#ifdef HAVE_NCURSESW_NCURSES_H
#include <ncursesw/ncurses.h>
#elif HAVE_NCURSES_H
#include <ncurses.h>
#endif

#include "command/command.h"
#include "common.h"
#include "config/accounts.h"
#include "config/preferences.h"
#include "config/theme.h"
#include "tools/history.h"
#include "log.h"
#include "muc.h"
#include "profanity.h"
#include "roster_list.h"
#include "ui/ui.h"
#include "ui/statusbar.h"
#include "ui/inputwin.h"
#include "ui/windows.h"
#include "xmpp/xmpp.h"
#include "ui/keyhandlers.h"

#define KEY_CTRL_A 0001
#define KEY_CTRL_B 0002
#define KEY_CTRL_D 0004
#define KEY_CTRL_E 0005
#define KEY_CTRL_F 0006
#define KEY_CTRL_N 0016
#define KEY_CTRL_P 0020
#define KEY_CTRL_U 0025
#define KEY_CTRL_W 0027

#define MAX_HISTORY 100

static WINDOW *inp_win;
static History history;

// input line
static char line[INP_WIN_MAX];
// current position in the utf8 string
static int line_utf8_pos;

static int pad_start = 0;

static int _handle_edit(int key_type, const wint_t ch);
static int _handle_alt_key(int key);

static void _handle_delete_previous_word(void);
static void _handle_backspace(void);

static gboolean _is_ctrl_left(int key_type, const wint_t ch);
static gboolean _is_ctrl_right(int key_type, const wint_t ch);

static void _inp_win_update_virtual(void);

void
create_input_window(void)
{
#ifdef NCURSES_REENTRANT
    set_escdelay(25);
#else
    ESCDELAY = 25;
#endif
    inp_win = newpad(1, INP_WIN_MAX);
    wbkgd(inp_win, theme_attrs(THEME_INPUT_TEXT));;
    keypad(inp_win, TRUE);
    wmove(inp_win, 0, 0);
    _inp_win_update_virtual();
    history = history_new(MAX_HISTORY);
    line_utf8_pos = 0;
    line[0] = '\0';
}

void
inp_win_resize(void)
{
    int col = getcurx(inp_win);
    int wcols = getmaxx(stdscr);

    // if lost cursor off screen, move contents to show it
    if (col >= pad_start + wcols) {
        pad_start = col - (wcols / 2);
        if (pad_start < 0) {
            pad_start = 0;
        }
    }

    wbkgd(inp_win, theme_attrs(THEME_INPUT_TEXT));;
    _inp_win_update_virtual();
}

static int
offset_to_col(char *str, int offset)
{
    int i = 0;
    int col = 0;
    mbstate_t internal;

    while (i != offset && str[i] != '\n') {
        gunichar uni = g_utf8_get_char(&str[i]);
        size_t ch_len = mbrlen(&str[i], 4, &internal);
        i += ch_len;
        col++;
        if (g_unichar_iswide(uni)) {
            col++;
        }
    }

    return col;
}

void
inp_write(char *line, int offset)
{
    int col = offset_to_col(line, offset);

    cons_debug("LEN BYTES: %d", strlen(line));
    cons_debug("LEN UTF8 : %d", g_utf8_strlen(line, -1));
    cons_debug("OFFSET   : %d", offset);
    cons_debug("COL      : %d", col);
    cons_debug("");

    werase(inp_win);
    waddstr(inp_win, line);
    wmove(inp_win, 0, col);
    _inp_win_update_virtual();
}

void
inp_non_block(gint timeout)
{
    wtimeout(inp_win, timeout);
}

void
inp_block(void)
{
    wtimeout(inp_win, -1);
}

char *
inp_read(int *key_type, wint_t *ch)
{
    // echo off, and get some more input
    noecho();
    *key_type = wget_wch(inp_win, ch);

    int bytes_len = strlen(line);

    gboolean in_command = FALSE;
    if ((bytes_len > 0 && line[0] == '/') ||
            (bytes_len == 0 && *ch == '/')) {
        in_command = TRUE;
    }

    if (*key_type == ERR) {
        prof_handle_idle();
    }
    if ((*key_type != ERR) && (*key_type != KEY_CODE_YES) && !in_command && utf8_is_printable(*ch)) {
        prof_handle_activity();
    }

    // if it wasn't an arrow key etc
    if (!_handle_edit(*key_type, *ch)) {
        if (utf8_is_printable(*ch) && *key_type != KEY_CODE_YES) {
            if (bytes_len >= INP_WIN_MAX) {
                *ch = ERR;
                return NULL;
            }

            int col = getcurx(inp_win);
            int maxx = getmaxx(stdscr);
            key_printable(line, &line_utf8_pos, &col, &pad_start, *ch, maxx);

            werase(inp_win);
            waddstr(inp_win, line);
            wmove(inp_win, 0, col);
            _inp_win_update_virtual();

            cmd_reset_autocomplete();
        }
    }

    echo();

    char *result = NULL;
    if (*ch == '\n') {
        result = strdup(line);
        line[0] = '\0';
        line_utf8_pos = 0;
    }

    if (*ch != ERR && *key_type != ERR) {
        cons_debug("BYTE LEN = %d", strlen(line));
        cons_debug("UTF8 LEN = %d", utf8_display_len(line));
        cons_debug("CURR COL = %d", getcurx(inp_win));
        cons_debug("CURR UNI = %d", line_utf8_pos);
        cons_debug("");
    }

    return result;
}

void
inp_get_password(char *passwd)
{
    werase(inp_win);
    wmove(inp_win, 0, 0);
    pad_start = 0;
    line[0] = '\0';
    line_utf8_pos = 0;
    _inp_win_update_virtual();
    doupdate();
    noecho();
    mvwgetnstr(inp_win, 0, 1, passwd, MAX_PASSWORD_SIZE);
    wmove(inp_win, 0, 0);
    echo();
    status_bar_clear();
}

void
inp_put_back(void)
{
    _inp_win_update_virtual();
}

void
inp_win_clear(void)
{
    werase(inp_win);
    wmove(inp_win, 0, 0);
    pad_start = 0;
    line[0] = '\0';
    line_utf8_pos = 0;
    _inp_win_update_virtual();
}

void
inp_history_append(char *inp)
{
    history_append(history, inp);
}

/*
 * Deal with command editing, return 1 if ch was an edit
 * key press: up, down, left, right or backspace
 * return 0 if it wasn't
 */
static int
_handle_edit(int key_type, const wint_t ch)
{
    int col = getcurx(inp_win);
    int utf8_len = g_utf8_strlen(line, -1);
    int wcols = getmaxx(stdscr);

    // CTRL-LEFT
    if (_is_ctrl_left(key_type, ch)) {
        key_ctrl_left(line, &line_utf8_pos, &col, &pad_start, wcols);
        wmove(inp_win, 0, col);
        return 1;

    // CTRL-RIGHT
    } else if (_is_ctrl_right(key_type, ch)) {
        key_ctrl_right(line, &line_utf8_pos, &col, &pad_start, wcols);
        wmove(inp_win, 0, col);
        return 1;

    // ALT-LEFT
    } else if ((key_type == KEY_CODE_YES) && (ch == 537 || ch == 542)) {
        ui_previous_win();
        return 1;

    // ALT-RIGHT
    } else if ((key_type == KEY_CODE_YES) && (ch == 552 || ch == 557)) {
        ui_next_win();
        return 1;

    // other editing keys
    } else {
        int display_len;
        int bytes_len = strlen(line);
        int next_ch;

        switch(ch) {

        case 27: // ESC
            // check for ALT-key
            next_ch = wgetch(inp_win);
            if (next_ch != ERR) {
                return _handle_alt_key(next_ch);
            } else {
                werase(inp_win);
                wmove(inp_win, 0, 0);
                pad_start = 0;
                line[0] = '\0';
                line_utf8_pos = 0;
                _inp_win_update_virtual();
                return 1;
            }

        case 127:
            _handle_backspace();
            return 1;
        case KEY_BACKSPACE:
            if (key_type != KEY_CODE_YES) {
                return 0;
            }
            _handle_backspace();
            return 1;

        case KEY_DC: // DEL
            if (key_type != KEY_CODE_YES) {
                return 0;
            }
        case KEY_CTRL_D:
            if (line_utf8_pos == utf8_len) {
                return 1;
            } else if (line_utf8_pos == utf8_len-1) {
                gchar *curr_ch = g_utf8_offset_to_pointer(line, line_utf8_pos);
                int bytes_len_ch = strlen(curr_ch);
                bytes_len -= bytes_len_ch;
                line[bytes_len] = '\0';
                line_utf8_pos--;
                wdelch(inp_win);

                return 1;
            } else if (line_utf8_pos < utf8_len-1) {
                gchar *start = g_utf8_substring(line, 0, col);
                gchar *end = g_utf8_substring(line, col+1, bytes_len);
                GString *new = g_string_new(start);
                g_string_append(new, end);

                for (bytes_len = 0; bytes_len < strlen(new->str); bytes_len++) {
                    line[bytes_len] = new->str[bytes_len];
                }
                line[bytes_len] = '\0';

                g_free(start);
                g_free(end);
                g_string_free(new, FALSE);

                werase(inp_win);
                wmove(inp_win, 0, 0);
                pad_start = 0;
                line[0] = '\0';
                line_utf8_pos = 0;
                waddstr(inp_win, line);
                wmove(inp_win, 0, col);
            }
            return 1;

        case KEY_LEFT:
            if (key_type != KEY_CODE_YES) {
                return 0;
            }
        case KEY_CTRL_B:
            if (line_utf8_pos > 0) {
                col--;
                gchar *curr_ch = g_utf8_offset_to_pointer(line, line_utf8_pos);
                gchar *prev_ch = g_utf8_find_prev_char(line, curr_ch);
                if (prev_ch) {
                    gunichar uni = g_utf8_get_char(prev_ch);
                    if (g_unichar_iswide(uni)) {
                        col--;
                    }
                }
                wmove(inp_win, 0, col);
                line_utf8_pos--;

                // current position off screen to left
                if (col < pad_start) {
                    pad_start--;
                    _inp_win_update_virtual();
                }
            }
            return 1;

        case KEY_RIGHT:
            if (key_type != KEY_CODE_YES) {
                return 0;
            }
        case KEY_CTRL_F:
            if (line_utf8_pos < utf8_len) {
                col++;
                gchar *curr_ch = g_utf8_offset_to_pointer(line, line_utf8_pos);
                if (curr_ch) {
                    gunichar uni = g_utf8_get_char(curr_ch);
                    if (g_unichar_iswide(uni)) {
                        col++;
                    }
                }
                wmove(inp_win, 0, col);
                line_utf8_pos++;

                // current position off screen to right
                int wcols = getmaxx(stdscr);
                if ((col - pad_start) >= wcols) {
                    pad_start++;
                    _inp_win_update_virtual();
                }
            }
            return 1;

        case KEY_UP:
            if (key_type != KEY_CODE_YES) {
                return 0;
            }
        case KEY_CTRL_P:
            line[bytes_len] = '\0';
            char *prev = history_previous(history, line);
            if (prev) {
                werase(inp_win);
                wmove(inp_win, 0, 0);
                pad_start = 0;
                line[0] = '\0';
                line_utf8_pos = 0;
                strncpy(line, prev, INP_WIN_MAX);
                waddstr(inp_win, line);

                int display_len = utf8_display_len(line);
                wmove(inp_win, 0, display_len);
                line_utf8_pos = g_utf8_strlen(line, -1);

                int wcols = getmaxx(stdscr);
                if (display_len > wcols-2) {
                    pad_start = display_len - wcols + 1;
                    _inp_win_update_virtual();
                }
            }
            return 1;

        case KEY_DOWN:
            if (key_type != KEY_CODE_YES) {
                return 0;
            }
        case KEY_CTRL_N:
            line[bytes_len] = '\0';
            char *next = history_next(history, line);
            if (next) {
                werase(inp_win);
                wmove(inp_win, 0, 0);
                pad_start = 0;
                line[0] = '\0';
                line_utf8_pos = 0;
                strncpy(line, next, INP_WIN_MAX);
                waddstr(inp_win, line);

                int display_len = utf8_display_len(line);
                wmove(inp_win, 0, display_len);
                line_utf8_pos = g_utf8_strlen(line, -1);

                int wcols = getmaxx(stdscr);
                if (display_len > wcols-2) {
                    pad_start = display_len - wcols + 1;
                    _inp_win_update_virtual();
                }
            } else if (bytes_len != 0) {
                line[bytes_len] = '\0';
                history_append(history, line);
                werase(inp_win);
                wmove(inp_win, 0, 0);
                pad_start = 0;
                line[0] = '\0';
                line_utf8_pos = 0;
                strncpy(line, "", INP_WIN_MAX);
                waddstr(inp_win, line);

                int display_len = utf8_display_len(line);
                wmove(inp_win, 0, display_len);
                line_utf8_pos = g_utf8_strlen(line, -1);

                int wcols = getmaxx(stdscr);
                if (display_len > wcols-2) {
                    pad_start = display_len - wcols + 1;
                    _inp_win_update_virtual();
                }
            }
            return 1;

        case KEY_HOME:
            if (key_type != KEY_CODE_YES) {
                return 0;
            }
        case KEY_CTRL_A:
            wmove(inp_win, 0, 0);
            pad_start = 0;
            line_utf8_pos = 0;
            _inp_win_update_virtual();
            return 1;

        case KEY_END:
            if (key_type != KEY_CODE_YES) {
                return 0;
            }
        case KEY_CTRL_E:
            display_len = utf8_display_len(line);
            wmove(inp_win, 0, display_len);
            line_utf8_pos = g_utf8_strlen(line, -1);

            int wcols = getmaxx(stdscr);
            if (display_len > wcols-2) {
                pad_start = display_len - wcols + 1;
                _inp_win_update_virtual();
            }
            return 1;

        case 9: // tab
            if (bytes_len != 0) {
                line[bytes_len] = '\0';
                if ((strncmp(line, "/", 1) != 0) && (ui_current_win_type() == WIN_MUC)) {
                    char *result = muc_autocomplete(line);
                    if (result) {
                        werase(inp_win);
                        wmove(inp_win, 0, 0);
                        pad_start = 0;
                        line[0] = '\0';
                        line_utf8_pos = 0;
                        strncpy(line, result, INP_WIN_MAX);
                        waddstr(inp_win, line);

                        int display_len = utf8_display_len(line);
                        wmove(inp_win, 0, display_len);
                        line_utf8_pos = g_utf8_strlen(line, -1);

                        int wcols = getmaxx(stdscr);
                        if (display_len > wcols-2) {
                            pad_start = display_len - wcols + 1;
                            _inp_win_update_virtual();
                        }

                        free(result);
                    }
                } else if (strncmp(line, "/", 1) == 0) {
                    char *result = cmd_autocomplete(line);
                    if (result) {
                        werase(inp_win);
                        wmove(inp_win, 0, 0);
                        pad_start = 0;
                        line[0] = '\0';
                        line_utf8_pos = 0;
                        strncpy(line, result, INP_WIN_MAX);
                        waddstr(inp_win, line);

                        int display_len = utf8_display_len(line);
                        wmove(inp_win, 0, display_len);
                        line_utf8_pos = g_utf8_strlen(line, -1);

                        int wcols = getmaxx(stdscr);
                        if (display_len > wcols-2) {
                            pad_start = display_len - wcols + 1;
                            _inp_win_update_virtual();
                        }

                        free(result);
                    }
                }
            }
            return 1;

        case KEY_CTRL_W:
            _handle_delete_previous_word();
            return 1;
            break;

        case KEY_CTRL_U:
            while (getcurx(inp_win) > 0) {
                _handle_delete_previous_word();
            }
            return 1;
            break;

        default:
            return 0;
        }
    }
}

static void
_handle_backspace(void)
{
    int col = getcurx(inp_win);
    int utf8_len = g_utf8_strlen(line, -1);
    roster_reset_search_attempts();

    if (utf8_len > 0) {
        // if at end, delete last char
        if (line_utf8_pos >= utf8_len) {
            gchar *new_line = g_utf8_substring(line, 0, utf8_len-1);
            werase(inp_win);
            wmove(inp_win, 0, 0);
            pad_start = 0;
            line[0] = '\0';
            line_utf8_pos = 0;
            strncpy(line, new_line, INP_WIN_MAX);
            waddstr(inp_win, line);

            int display_len = utf8_display_len(line);
            wmove(inp_win, 0, display_len);
            line_utf8_pos = g_utf8_strlen(line, -1);

            int wcols = getmaxx(stdscr);
            if (display_len > wcols-2) {
                pad_start = display_len - wcols + 1;
                _inp_win_update_virtual();
            }

        // if in middle, delete and shift chars left
        } else if (line_utf8_pos > 0 && line_utf8_pos < utf8_len) {
            gchar *del_char = g_utf8_offset_to_pointer(line, line_utf8_pos-1);
            gunichar uni = g_utf8_get_char(del_char);

            gchar *start = g_utf8_substring(line, 0, line_utf8_pos-1);
            gchar *end = g_utf8_substring(line, line_utf8_pos, utf8_len);
            GString *new_line = g_string_new(start);
            g_string_append(new_line, end);

            int old_pos = line_utf8_pos;
            werase(inp_win);
            wmove(inp_win, 0, 0);
            pad_start = 0;
            line[0] = '\0';
            line_utf8_pos = 0;
            strncpy(line, new_line->str, INP_WIN_MAX);
            waddstr(inp_win, line);

            int display_len = utf8_display_len(line);
            wmove(inp_win, 0, display_len);
            line_utf8_pos = g_utf8_strlen(line, -1);

            int wcols = getmaxx(stdscr);
            if (display_len > wcols-2) {
                pad_start = display_len - wcols + 1;
                _inp_win_update_virtual();
            }

            line_utf8_pos = old_pos-1;

            g_free(start);
            g_free(end);
            g_string_free(new_line, TRUE);

            col--;
            if (g_unichar_iswide(uni)) {
                col--;
            }

            wmove(inp_win, 0, col);
        }

        // if gone off screen to left, jump left (half a screen worth)
        if (col <= pad_start) {
            int wcols = getmaxx(stdscr);
            pad_start = pad_start - (wcols / 2);
            if (pad_start < 0) {
                pad_start = 0;
            }

            _inp_win_update_virtual();
        }
    }

}

static int
_handle_alt_key(int key)
{
    switch (key)
    {
        case '1':
            ui_switch_win(1);
            break;
        case '2':
            ui_switch_win(2);
            break;
        case '3':
            ui_switch_win(3);
            break;
        case '4':
            ui_switch_win(4);
            break;
        case '5':
            ui_switch_win(5);
            break;
        case '6':
            ui_switch_win(6);
            break;
        case '7':
            ui_switch_win(7);
            break;
        case '8':
            ui_switch_win(8);
            break;
        case '9':
            ui_switch_win(9);
            break;
        case '0':
            ui_switch_win(0);
            break;
        case KEY_LEFT:
            ui_previous_win();
            break;
        case KEY_RIGHT:
            ui_next_win();
            break;
        case 263:
        case 127:
            _handle_delete_previous_word();
            break;
        default:
            break;
    }
    return 1;
}

static void
_handle_delete_previous_word(void)
{
    int end_del = getcurx(inp_win);
    int start_del = end_del;

    gchar *curr_ch = g_utf8_offset_to_pointer(line, end_del);
    curr_ch = g_utf8_find_prev_char(line, curr_ch);
    gchar *prev_ch;
    gunichar curr_uni;
    gunichar prev_uni;

    while (curr_ch != NULL) {
        curr_uni = g_utf8_get_char(curr_ch);

        if (g_unichar_isspace(curr_uni)) {
            curr_ch = g_utf8_find_prev_char(line, curr_ch);
        } else {
            prev_ch = g_utf8_find_prev_char(line, curr_ch);
            if (prev_ch == NULL) {
                curr_ch = NULL;
                break;
            } else {
                prev_uni = g_utf8_get_char(prev_ch);
                if (g_unichar_isspace(prev_uni)) {
                    break;
                } else {
                    curr_ch = prev_ch;
                }
            }
        }
    }

    if (curr_ch == NULL) {
        start_del = 0;
    } else {
        start_del = g_utf8_pointer_to_offset(line, curr_ch);
    }

    gint len = g_utf8_strlen(line, -1);
    gchar *start_string = g_utf8_substring(line, 0, start_del);
    gchar *end_string = g_utf8_substring(line, end_del, len);

    int i;
    for (i = 0; i < strlen(start_string); i++) {
        line[i] = start_string[i];
    }
    for (i = 0; i < strlen(end_string); i++) {
        line[strlen(start_string)+i] = end_string[i];
    }

    int bytes_len = strlen(start_string)+i;
    line[bytes_len] = '\0';

    werase(inp_win);
    wmove(inp_win, 0, 0);
    pad_start = 0;
    line[0] = '\0';
    line_utf8_pos = 0;

    waddstr(inp_win, line);
    wmove(inp_win, 0, start_del);

    // if gone off screen to left, jump left (half a screen worth)
    if (start_del <= pad_start) {
        int wcols = getmaxx(stdscr);
        pad_start = pad_start - (wcols / 2);
        if (pad_start < 0) {
            pad_start = 0;
        }

        _inp_win_update_virtual();
    }
}

static gboolean
_is_ctrl_left(int key_type, const wint_t ch)
{
    return ((key_type == KEY_CODE_YES)
        && (ch == 547 || ch == 545 || ch == 544 || ch == 540 || ch == 539));
}

static gboolean
_is_ctrl_right(int key_type, const wint_t ch)
{
    return ((key_type == KEY_CODE_YES)
        && (ch == 562 || ch == 560 || ch == 555 || ch == 559 || ch == 554));
}

static void
_inp_win_update_virtual(void)
{
    int wrows, wcols;
    getmaxyx(stdscr, wrows, wcols);
    pnoutrefresh(inp_win, 0, pad_start, wrows-1, 0, wrows-1, wcols-1);
}