/*

 * QEMU readline utility

 *

 * Copyright (c) 2003-2004 Fabrice Bellard

 *

 * Permission is hereby granted, free of charge, to any person obtaining a copy

 * of this software and associated documentation files (the "Software"), to deal

 * in the Software without restriction, including without limitation the rights

 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

 * copies of the Software, and to permit persons to whom the Software is

 * furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice shall be included in

 * all copies or substantial portions of the Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL

 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

 * THE SOFTWARE.

 */

#include "qemu-common.h"

#include "console.h"

#define TERM_CMD_BUF_SIZE 4095

#define TERM_MAX_CMDS 64

#define NB_COMPLETIONS_MAX 256

#define IS_NORM 0

#define IS_ESC  1

#define IS_CSI  2

#define printf do_not_use_printf

static char term_cmd_buf[TERM_CMD_BUF_SIZE + 1];

static int term_cmd_buf_index;

static int term_cmd_buf_size;

static char term_last_cmd_buf[TERM_CMD_BUF_SIZE + 1];

static int term_last_cmd_buf_index;

static int term_last_cmd_buf_size;

static int term_esc_state;

static int term_esc_param;

static char *term_history[TERM_MAX_CMDS];

static int term_hist_entry = -1;

static int nb_completions;

int completion_index;

static char *completions[NB_COMPLETIONS_MAX];

static ReadLineFunc *term_readline_func;

static int term_is_password;

static char term_prompt[256];

static void *term_readline_opaque;

static void term_show_prompt2(void)

{

    term_printf("%s", term_prompt);

    term_flush();

    term_last_cmd_buf_index = 0;

    term_last_cmd_buf_size = 0;

    term_esc_state = IS_NORM;

}

static void term_show_prompt(void)

{

    term_show_prompt2();

    term_cmd_buf_index = 0;

    term_cmd_buf_size = 0;

}

/* update the displayed command line */

static void term_update(void)

{

    int i, delta, len;

    if (term_cmd_buf_size != term_last_cmd_buf_size ||

        memcmp(term_cmd_buf, term_last_cmd_buf, term_cmd_buf_size) != 0) {

        for(i = 0; i < term_last_cmd_buf_index; i++) {

            term_printf("\033[D");

        }

        term_cmd_buf[term_cmd_buf_size] = '\0';

        if (term_is_password) {

            len = strlen(term_cmd_buf);

            for(i = 0; i < len; i++)

                term_printf("*");

        } else {

            term_printf("%s", term_cmd_buf);

        }

        term_printf("\033[K");

        memcpy(term_last_cmd_buf, term_cmd_buf, term_cmd_buf_size);

        term_last_cmd_buf_size = term_cmd_buf_size;

        term_last_cmd_buf_index = term_cmd_buf_size;

    }

    if (term_cmd_buf_index != term_last_cmd_buf_index) {

        delta = term_cmd_buf_index - term_last_cmd_buf_index;

        if (delta > 0) {

            for(i = 0;i < delta; i++) {

                term_printf("\033[C");

            }

        } else {

            delta = -delta;

            for(i = 0;i < delta; i++) {

                term_printf("\033[D");

            }

        }

        term_last_cmd_buf_index = term_cmd_buf_index;

    }

    term_flush();

}

static void term_insert_char(int ch)

{

    if (term_cmd_buf_index < TERM_CMD_BUF_SIZE) {

        memmove(term_cmd_buf + term_cmd_buf_index + 1,

                term_cmd_buf + term_cmd_buf_index,

                term_cmd_buf_size - term_cmd_buf_index);

        term_cmd_buf[term_cmd_buf_index] = ch;

        term_cmd_buf_size++;

        term_cmd_buf_index++;

    }

}

static void term_backward_char(void)

{

    if (term_cmd_buf_index > 0) {

        term_cmd_buf_index--;

    }

}

static void term_forward_char(void)

{

    if (term_cmd_buf_index < term_cmd_buf_size) {

        term_cmd_buf_index++;

    }

}

static void term_delete_char(void)

{

    if (term_cmd_buf_index < term_cmd_buf_size) {

        memmove(term_cmd_buf + term_cmd_buf_index,

                term_cmd_buf + term_cmd_buf_index + 1,

                term_cmd_buf_size - term_cmd_buf_index - 1);

        term_cmd_buf_size--;

    }

}

static void term_backspace(void)

{

    if (term_cmd_buf_index > 0) {

        term_backward_char();

        term_delete_char();

    }

}

static void term_backword(void)

{

    int start;

    if (term_cmd_buf_index == 0 || term_cmd_buf_index > term_cmd_buf_size) {

        return;

    }

    start = term_cmd_buf_index - 1;

    /* find first word (backwards) */

    while (start > 0) {

        if (!qemu_isspace(term_cmd_buf[start])) {

            break;

        }

        --start;

    }

    /* find first space (backwards) */

    while (start > 0) {

        if (qemu_isspace(term_cmd_buf[start])) {

            ++start;

            break;

        }

        --start;

    }

    /* remove word */

    if (start < term_cmd_buf_index) {

        memmove(term_cmd_buf + start,

                term_cmd_buf + term_cmd_buf_index,

                term_cmd_buf_size - term_cmd_buf_index);

        term_cmd_buf_size -= term_cmd_buf_index - start;

        term_cmd_buf_index = start;

    }

}

static void term_bol(void)

{

    term_cmd_buf_index = 0;

}

static void term_eol(void)

{

    term_cmd_buf_index = term_cmd_buf_size;

}

static void term_up_char(void)

{

    int idx;

    if (term_hist_entry == 0)

	return;

    if (term_hist_entry == -1) {

	/* Find latest entry */

	for (idx = 0; idx < TERM_MAX_CMDS; idx++) {

	    if (term_history[idx] == NULL)

		break;

	}

	term_hist_entry = idx;

    }

    term_hist_entry--;

    if (term_hist_entry >= 0) {

	pstrcpy(term_cmd_buf, sizeof(term_cmd_buf),

                term_history[term_hist_entry]);

	term_cmd_buf_index = term_cmd_buf_size = strlen(term_cmd_buf);

    }

}

static void term_down_char(void)

{

    if (term_hist_entry == TERM_MAX_CMDS - 1 || term_hist_entry == -1)

	return;

    if (term_history[++term_hist_entry] != NULL) {

	pstrcpy(term_cmd_buf, sizeof(term_cmd_buf),

                term_history[term_hist_entry]);

    } else {

	term_hist_entry = -1;

    }

    term_cmd_buf_index = term_cmd_buf_size = strlen(term_cmd_buf);

}

static void term_hist_add(const char *cmdline)

{

    char *hist_entry, *new_entry;

    int idx;

    if (cmdline[0] == '\0')

	return;

    new_entry = NULL;

    if (term_hist_entry != -1) {

	/* We were editing an existing history entry: replace it */

	hist_entry = term_history[term_hist_entry];

	idx = term_hist_entry;

	if (strcmp(hist_entry, cmdline) == 0) {

	    goto same_entry;

	}

    }

    /* Search cmdline in history buffers */

    for (idx = 0; idx < TERM_MAX_CMDS; idx++) {

	hist_entry = term_history[idx];

	if (hist_entry == NULL)

	    break;

	if (strcmp(hist_entry, cmdline) == 0) {

	same_entry:

	    new_entry = hist_entry;

	    /* Put this entry at the end of history */

	    memmove(&term_history[idx], &term_history[idx + 1],

		    (TERM_MAX_CMDS - idx + 1) * sizeof(char *));

	    term_history[TERM_MAX_CMDS - 1] = NULL;

	    for (; idx < TERM_MAX_CMDS; idx++) {

		if (term_history[idx] == NULL)

		    break;

	    }

	    break;

	}

    }

    if (idx == TERM_MAX_CMDS) {

	/* Need to get one free slot */

	free(term_history[0]);

	memcpy(term_history, &term_history[1],

	       (TERM_MAX_CMDS - 1) * sizeof(char *));

	term_history[TERM_MAX_CMDS - 1] = NULL;

	idx = TERM_MAX_CMDS - 1;

    }

    if (new_entry == NULL)

	new_entry = strdup(cmdline);

    term_history[idx] = new_entry;

    term_hist_entry = -1;

}

/* completion support */

void add_completion(const char *str)

{

    if (nb_completions < NB_COMPLETIONS_MAX) {

        completions[nb_completions++] = qemu_strdup(str);

    }

}

static void term_completion(void)

{

    int len, i, j, max_width, nb_cols, max_prefix;

    char *cmdline;

    nb_completions = 0;

    cmdline = qemu_malloc(term_cmd_buf_index + 1);

    if (!cmdline)

        return;

    memcpy(cmdline, term_cmd_buf, term_cmd_buf_index);

    cmdline[term_cmd_buf_index] = '\0';

    readline_find_completion(cmdline);

    qemu_free(cmdline);

    /* no completion found */

    if (nb_completions <= 0)

        return;

    if (nb_completions == 1) {

        len = strlen(completions[0]);

        for(i = completion_index; i < len; i++) {

            term_insert_char(completions[0][i]);

        }

        /* extra space for next argument. XXX: make it more generic */

        if (len > 0 && completions[0][len - 1] != '/')

            term_insert_char(' ');

    } else {

        term_printf("\n");

        max_width = 0;

        max_prefix = 0;	

        for(i = 0; i < nb_completions; i++) {

            len = strlen(completions[i]);

            if (i==0) {

                max_prefix = len;

            } else {

                if (len < max_prefix)

                    max_prefix = len;

                for(j=0; j<max_prefix; j++) {

                    if (completions[i][j] != completions[0][j])

                        max_prefix = j;

                }

            }

            if (len > max_width)

                max_width = len;

        }

        if (max_prefix > 0) 

            for(i = completion_index; i < max_prefix; i++) {

                term_insert_char(completions[0][i]);

            }

        max_width += 2;

        if (max_width < 10)

            max_width = 10;

        else if (max_width > 80)

            max_width = 80;

        nb_cols = 80 / max_width;

        j = 0;

        for(i = 0; i < nb_completions; i++) {

            term_printf("%-*s", max_width, completions[i]);

            if (++j == nb_cols || i == (nb_completions - 1)) {

                term_printf("\n");

                j = 0;

            }

        }

        term_show_prompt2();

    }

}

/* return true if command handled */

void readline_handle_byte(int ch)

{

    switch(term_esc_state) {

    case IS_NORM:

        switch(ch) {

        case 1:

            term_bol();

            break;

        case 4:

            term_delete_char();

            break;

        case 5:

            term_eol();

            break;

        case 9:

            term_completion();

            break;

        case 10:

        case 13:

            term_cmd_buf[term_cmd_buf_size] = '\0';

            if (!term_is_password)

                term_hist_add(term_cmd_buf);

            term_printf("\n");

            term_cmd_buf_index = 0;

            term_cmd_buf_size = 0;

            term_last_cmd_buf_index = 0;

            term_last_cmd_buf_size = 0;

            /* NOTE: readline_start can be called here */

            term_readline_func(term_readline_opaque, term_cmd_buf);

            break;

        case 23:

            /* ^W */

            term_backword();

            break;

        case 27:

            term_esc_state = IS_ESC;

            break;

        case 127:

        case 8:

            term_backspace();

            break;

	case 155:

            term_esc_state = IS_CSI;

	    break;

        default:

            if (ch >= 32) {

                term_insert_char(ch);

            }

            break;

        }

        break;

    case IS_ESC:

        if (ch == '[') {

            term_esc_state = IS_CSI;

            term_esc_param = 0;

        } else {

            term_esc_state = IS_NORM;

        }

        break;

    case IS_CSI:

        switch(ch) {

	case 'A':

	case 'F':

	    term_up_char();

	    break;

	case 'B':

	case 'E':

	    term_down_char();

	    break;

        case 'D':

            term_backward_char();

            break;

        case 'C':

            term_forward_char();

            break;

        case '0' ... '9':

            term_esc_param = term_esc_param * 10 + (ch - '0');

            goto the_end;

        case '~':

            switch(term_esc_param) {

            case 1:

                term_bol();

                break;

            case 3:

                term_delete_char();

                break;

            case 4:

                term_eol();

                break;

            }

            break;

        default:

            break;

        }

        term_esc_state = IS_NORM;

    the_end:

        break;

    }

    term_update();

}

void readline_start(const char *prompt, int is_password,

                    ReadLineFunc *readline_func, void *opaque)

{

    pstrcpy(term_prompt, sizeof(term_prompt), prompt);

    term_readline_func = readline_func;

    term_readline_opaque = opaque;

    term_is_password = is_password;

    term_show_prompt();

}

const char *readline_get_history(unsigned int index)

{

    if (index >= TERM_MAX_CMDS)

        return NULL;

    return term_history[index];

}