/*
 * 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/>.
 *
 */

#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 "log.h"
#include "profanity.h"
#include "roster_list.h"
#include "ui/ui.h"
#include "ui/windows.h"
#include "xmpp/xmpp.h"

#define _inp_win_update_virtual() pnoutrefresh(inp_win, 0, pad_start, rows-1, 0, rows-1, cols-1)

static WINDOW *inp_win;
static int pad_start = 0;
static int rows, cols;

static int _handle_edit(int result, const wint_t ch, char *input, int *size);
static int _handle_alt_key(char *input, int *size, int key);
static void _handle_backspace(int display_size, int inp_x, int *size, char *input);
static int _printable(const wint_t ch);
static void _clear_input(void);
static void _go_to_end(int display_size);

static void
_create_input_window(void)
{
#ifdef NCURSES_REENTRANT
    set_escdelay(25);
#else
    ESCDELAY = 25;
#endif
    getmaxyx(stdscr, rows, cols);
    inp_win = newpad(1, INP_WIN_MAX);
    wbkgd(inp_win, COLOUR_INPUT_TEXT);
    keypad(inp_win, TRUE);
    wmove(inp_win, 0, 0);
    _inp_win_update_virtual();
}

static void
_inp_win_resize(const char * const input, const int size)
{
    int inp_x;
    getmaxyx(stdscr, rows, cols);
    inp_x = getcurx(inp_win);

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

    _inp_win_update_virtual();
}

static void
_inp_non_block(void)
{
    wtimeout(inp_win, 20);
}

static void
_inp_block(void)
{
    wtimeout(inp_win, -1);
}

static wint_t
_inp_get_char(char *input, int *size)
{
    int inp_x = 0;
    int i;
    wint_t ch;
    int display_size = 0;

    if (*size != 0) {
        display_size = g_utf8_strlen(input, *size);
    }

    // echo off, and get some more input
    noecho();
    int result = wget_wch(inp_win, &ch);

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

    if (prefs_get_boolean(PREF_STATES)) {
        if (result == ERR) {
            prof_handle_idle();
        }
        if (prefs_get_boolean(PREF_OUTTYPE)
                && (result != ERR)
                && (result != KEY_CODE_YES)
                && !in_command
                && _printable(ch)) {
            prof_handle_activity();
        }
    }

    // if it wasn't an arrow key etc
    if (!_handle_edit(result, ch, input, size)) {
        if (_printable(ch) && result != KEY_CODE_YES) {
            if (*size >= INP_WIN_MAX) {
                return ERR;
            }

            inp_x = getcurx(inp_win);

            // handle insert if not at end of input
            if (inp_x < display_size) {
                char bytes[MB_CUR_MAX];
                size_t utf_len = wcrtomb(bytes, ch, NULL);

                char *next_ch = g_utf8_offset_to_pointer(input, inp_x);
                char *offset;
                for (offset = &input[*size - 1]; offset >= next_ch; offset--) {
                    *(offset + utf_len) = *offset;
                }
                for (i = 0; i < utf_len; i++) {
                     *(next_ch + i) = bytes[i];
                }

                *size += utf_len;
                input[*size] = '\0';
                waddstr(inp_win, next_ch);
                wmove(inp_win, 0, inp_x + 1);

                if (inp_x - pad_start > cols-3) {
                    pad_start++;
                    _inp_win_update_virtual();
                }

            // otherwise just append
            } else {
                char bytes[MB_CUR_MAX+1];
                size_t utf_len = wcrtomb(bytes, ch, NULL);

                // wcrtomb can return (size_t) -1
                if (utf_len < MB_CUR_MAX) {
                    for (i = 0 ; i < utf_len; i++) {
                        input[(*size)++] = bytes[i];
                    }
                    input[*size] = '\0';

                    bytes[utf_len] = '\0';
                    waddstr(inp_win, bytes);
                    display_size++;

                    // if gone over screen size follow input
                    int rows, cols;
                    getmaxyx(stdscr, rows, cols);
                    if (display_size - pad_start > cols-2) {
                        pad_start++;
                        _inp_win_update_virtual();
                    }
                }
            }

            cmd_reset_autocomplete();
        }
    }

    echo();

    return ch;
}

static void
_inp_get_password(char *passwd)
{
    _clear_input();
    _inp_win_update_virtual();
    doupdate();
    noecho();
    mvwgetnstr(inp_win, 0, 1, passwd, MAX_PASSWORD_SIZE);
    wmove(inp_win, 0, 0);
    echo();
    status_bar_clear();
}

static void
_inp_put_back(void)
{
    _inp_win_update_virtual();
}

static void
_inp_replace_input(char *input, const char * const new_input, int *size)
{
    int display_size;
    strncpy(input, new_input, INP_WIN_MAX);
    *size = strlen(input);
    display_size = g_utf8_strlen(input, *size);
    inp_win_reset();
    input[*size] = '\0';
    waddstr(inp_win, input);
    _go_to_end(display_size);
}

static void
_inp_win_reset(void)
{
    _clear_input();
    pad_start = 0;
    _inp_win_update_virtual();
}

static void
_clear_input(void)
{
    werase(inp_win);
    wmove(inp_win, 0, 0);
}

/*
 * Deal with command editing, return 1 if ch was an edit
 * key press: up, down, left, right or backspace
 * return 0 if it wasnt
 */
static int
_handle_edit(int result, const wint_t ch, char *input, int *size)
{
    char *prev = NULL;
    char *next = NULL;
    int inp_x = 0;
    int next_ch;
    int display_size = 0;

    if (*size != 0) {
        display_size = g_utf8_strlen(input, *size);
    }

    inp_x = getcurx(inp_win);

    // CTRL-LEFT
    if ((result == KEY_CODE_YES) && (ch == 547 || ch == 545 || ch == 540 || ch == 539) && (inp_x > 0)) {
        input[*size] = '\0';
        gchar *curr_ch = g_utf8_offset_to_pointer(input, inp_x);
        curr_ch = g_utf8_find_prev_char(input, 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(input, curr_ch);
            } else {
                prev_ch = g_utf8_find_prev_char(input, 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) {
            inp_x = 0;
            wmove(inp_win, 0, inp_x);
        } else {
            glong offset = g_utf8_pointer_to_offset(input, curr_ch);
            inp_x = offset;
            wmove(inp_win, 0, inp_x);
        }

        // if gone off screen to left, jump left (half a screen worth)
        if (inp_x <= pad_start) {
            pad_start = pad_start - (cols / 2);
            if (pad_start < 0) {
                pad_start = 0;
            }

            _inp_win_update_virtual();
        }
        return 1;

    // CTRL-RIGHT
    } else if ((result == KEY_CODE_YES) && (ch == 562 || ch == 560 || ch == 555 || ch == 554) && (inp_x < display_size)) {
        input[*size] = '\0';
        gchar *curr_ch = g_utf8_offset_to_pointer(input, inp_x);
        gchar *next_ch = g_utf8_find_next_char(curr_ch, NULL);
        gunichar curr_uni;
        gunichar next_uni;
        gboolean moved = FALSE;

        while (g_utf8_pointer_to_offset(input, next_ch) < display_size) {
            curr_uni = g_utf8_get_char(curr_ch);
            next_uni = g_utf8_get_char(next_ch);
            curr_ch = next_ch;
            next_ch = g_utf8_find_next_char(next_ch, NULL);

            if (!g_unichar_isspace(curr_uni) && g_unichar_isspace(next_uni) && moved) {
                break;
            } else {
                moved = TRUE;
            }
        }

        if (next_ch == NULL) {
            inp_x = display_size;
            wmove(inp_win, 0, inp_x);
        } else {
            glong offset = g_utf8_pointer_to_offset(input, curr_ch);
            if (offset == display_size - 1) {
                inp_x = offset + 1;
            } else {
                inp_x = offset;
            }
            wmove(inp_win, 0, inp_x);
        }

        // if gone off screen to right, jump right (half a screen worth)
        if (inp_x > pad_start + cols) {
            pad_start = pad_start + (cols / 2);
            _inp_win_update_virtual();
        }

        return 1;

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

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

    // other editing keys
    } else {
        switch(ch) {

        case 27: // ESC
            // check for ALT-key
            next_ch = wgetch(inp_win);
            if (next_ch != ERR) {
                return _handle_alt_key(input, size, next_ch);
            } else {
                *size = 0;
                inp_win_reset();
                return 1;
            }

        case 127:
            _handle_backspace(display_size, inp_x, size, input);
            return 1;
        case KEY_BACKSPACE:
            if (result != KEY_CODE_YES) {
                return 0;
            }
            _handle_backspace(display_size, inp_x, size, input);
            return 1;

        case KEY_DC: // DEL
            if (result != KEY_CODE_YES) {
                return 0;
            }
            if (inp_x == display_size-1) {
                gchar *start = g_utf8_substring(input, 0, inp_x);
                for (*size = 0; *size < strlen(start); (*size)++) {
                    input[*size] = start[*size];
                }
                input[*size] = '\0';

                g_free(start);

                _clear_input();
                waddstr(inp_win, input);
            } else if (inp_x < display_size-1) {
                gchar *start = g_utf8_substring(input, 0, inp_x);
                gchar *end = g_utf8_substring(input, inp_x+1, *size);
                GString *new = g_string_new(start);
                g_string_append(new, end);

                for (*size = 0; *size < strlen(new->str); (*size)++) {
                    input[*size] = new->str[*size];
                }
                input[*size] = '\0';

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

                _clear_input();
                waddstr(inp_win, input);
                wmove(inp_win, 0, inp_x);
            }
            return 1;

        case KEY_LEFT:
            if (result != KEY_CODE_YES) {
                return 0;
            }
            if (inp_x > 0) {
                wmove(inp_win, 0, inp_x-1);

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

        case KEY_RIGHT:
            if (result != KEY_CODE_YES) {
                return 0;
            }
            if (inp_x < display_size) {
                wmove(inp_win, 0, inp_x+1);

                // current position off screen to right
                if ((inp_x + 1 - pad_start) >= cols) {
                    pad_start++;
                    _inp_win_update_virtual();
                }
            }
            return 1;

        case KEY_UP:
            if (result != KEY_CODE_YES) {
                return 0;
            }
            prev = cmd_history_previous(input, size);
            if (prev) {
                inp_replace_input(input, prev, size);
            }
            return 1;

        case KEY_DOWN:
            if (result != KEY_CODE_YES) {
                return 0;
            }
            next = cmd_history_next(input, size);
            if (next) {
                inp_replace_input(input, next, size);
            } else if (*size != 0) {
                input[*size] = '\0';
                cmd_history_append(input);
                inp_replace_input(input, "", size);
            }
            return 1;

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

        case KEY_END:
            if (result != KEY_CODE_YES) {
                return 0;
            }
            _go_to_end(display_size);
            return 1;

        case 9: // tab
            cmd_autocomplete(input, size);
            return 1;

        default:
            return 0;
        }
    }
}

static void
_handle_backspace(int display_size, int inp_x, int *size, char *input)
{
    roster_reset_search_attempts();
    if (display_size > 0) {

        // if at end, delete last char
        if (inp_x >= display_size) {
            gchar *start = g_utf8_substring(input, 0, inp_x-1);
            for (*size = 0; *size < strlen(start); (*size)++) {
                input[*size] = start[*size];
            }
            input[*size] = '\0';

            g_free(start);

            _clear_input();
            waddstr(inp_win, input);
            wmove(inp_win, 0, inp_x -1);

        // if in middle, delete and shift chars left
        } else if (inp_x > 0 && inp_x < display_size) {
            gchar *start = g_utf8_substring(input, 0, inp_x - 1);
            gchar *end = g_utf8_substring(input, inp_x, *size);
            GString *new = g_string_new(start);
            g_string_append(new, end);

            for (*size = 0; *size < strlen(new->str); (*size)++) {
                input[*size] = new->str[*size];
            }
            input[*size] = '\0';

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

            _clear_input();
            waddstr(inp_win, input);
            wmove(inp_win, 0, inp_x -1);
        }

        // if gone off screen to left, jump left (half a screen worth)
        if (inp_x <= pad_start) {
            pad_start = pad_start - (cols / 2);
            if (pad_start < 0) {
                pad_start = 0;
            }

            _inp_win_update_virtual();
        }
    }

}

static int
_handle_alt_key(char *input, int *size, int key)
{
    int end_del = getcurx(inp_win);
    int start_del = end_del;

    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:
            input[*size] = '\0';
            gchar *curr_ch = g_utf8_offset_to_pointer(input, end_del);
            curr_ch = g_utf8_find_prev_char(input, 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(input, curr_ch);
                } else {
                    prev_ch = g_utf8_find_prev_char(input, 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(input, curr_ch);
            }

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

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

            *size = strlen(start_string)+i;
            input[*size] = '\0';

            _clear_input();
            waddstr(inp_win, input);
            wmove(inp_win, 0, start_del);

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

                _inp_win_update_virtual();
            }

            return 1;
            break;
        default:
            break;
    }
    return 1;
}

static void
_go_to_end(int display_size)
{
    wmove(inp_win, 0, display_size);
    if (display_size > cols-2) {
        pad_start = display_size - cols + 1;
        _inp_win_update_virtual();
    }
}

static int
_printable(const wint_t ch)
{
    char bytes[MB_CUR_MAX+1];
    size_t utf_len = wcrtomb(bytes, ch, NULL);
    bytes[utf_len] = '\0';
    gunichar unichar = g_utf8_get_char(bytes);
    return g_unichar_isprint(unichar) && (ch != KEY_MOUSE);
}

void
inputwin_init_module(void)
{
    create_input_window = _create_input_window;
    inp_win_resize = _inp_win_resize;
    inp_non_block = _inp_non_block;
    inp_block = _inp_block;
    inp_get_char = _inp_get_char;
    inp_get_password = _inp_get_password;
    inp_put_back = _inp_put_back;
    inp_replace_input = _inp_replace_input;
    inp_win_reset = _inp_win_reset;
}