/* Copyright 2017 Jack Humbert
 *
 * This program 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 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "process_terminal.h"
#include <string.h>
#include "version.h"
#include <stdio.h>
#include <math.h>

#ifndef CMD_BUFF_SIZE
#    define CMD_BUFF_SIZE 5
#endif

bool terminal_enabled = false;
char buffer[80]       = "";
char cmd_buffer[CMD_BUFF_SIZE][80];
bool cmd_buffer_enabled = true;  // replace with ifdef?
char newline[2]         = "\n";
char arguments[6][20];
bool firstTime = true;

short int current_cmd_buffer_pos = 0;  // used for up/down arrows - keeps track of where you are in the command buffer

__attribute__((weak)) const char terminal_prompt[8] = "> ";

#ifdef AUDIO_ENABLE
#    ifndef TERMINAL_SONG
#        define TERMINAL_SONG SONG(TERMINAL_SOUND)
#    endif
float terminal_song[][2] = TERMINAL_SONG;
#    define TERMINAL_BELL() PLAY_SONG(terminal_song)
#else
#    define TERMINAL_BELL()
#endif

__attribute__((weak)) const char keycode_to_ascii_lut[58] = {0, 0, 0, 0, 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', '1', '2', '3', '4', '5', '6', '7', '8', '9', '0', 0, 0, 0, '\t', ' ', '-', '=', '[', ']', '\\', 0, ';', '\'', '`', ',', '.', '/'};

__attribute__((weak)) const char shifted_keycode_to_ascii_lut[58] = {0, 0, 0, 0, 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', '!', '@', '#', '$', '%', '^', '&', '*', '(', ')', 0, 0, 0, '\t', ' ', '_', '+', '{', '}', '|', 0, ':', '\'', '~', '<', '>', '?'};

struct stringcase {
    char *string;
    void (*func)(void);
} typedef stringcase;

void enable_terminal(void) {
    terminal_enabled = true;
    strcpy(buffer, "");
    memset(cmd_buffer, 0, CMD_BUFF_SIZE * 80);
    for (int i = 0; i < 6; i++) strcpy(arguments[i], "");
    // select all text to start over
    // SEND_STRING(SS_LCTL("a"));
    send_string(terminal_prompt);
}

void disable_terminal(void) {
    terminal_enabled = false;
    SEND_STRING("\n");
}

void push_to_cmd_buffer(void) {
    if (cmd_buffer_enabled) {
        if (cmd_buffer == NULL) {
            return;
        } else {
            if (firstTime) {
                firstTime = false;
                strcpy(cmd_buffer[0], buffer);
                return;
            }

            for (int i = CMD_BUFF_SIZE - 1; i > 0; --i) {
                strncpy(cmd_buffer[i], cmd_buffer[i - 1], 80);
            }

            strcpy(cmd_buffer[0], buffer);

            return;
        }
    }
}

void terminal_about(void) {
    SEND_STRING("QMK Firmware\n");
    SEND_STRING("  v");
    SEND_STRING(QMK_VERSION);
    SEND_STRING("\n" SS_TAP(X_HOME) "  Built: ");
    SEND_STRING(QMK_BUILDDATE);
    send_string(newline);
#ifdef TERMINAL_HELP
    if (strlen(arguments[1]) != 0) {
        SEND_STRING("You entered: ");
        send_string(arguments[1]);
        send_string(newline);
    }
#endif
}

void terminal_help(void);

extern const uint16_t keymaps[][MATRIX_ROWS][MATRIX_COLS];

void terminal_keycode(void) {
    if (strlen(arguments[1]) != 0 && strlen(arguments[2]) != 0 && strlen(arguments[3]) != 0) {
        char     keycode_dec[5];
        char     keycode_hex[5];
        uint16_t layer   = strtol(arguments[1], (char **)NULL, 10);
        uint16_t row     = strtol(arguments[2], (char **)NULL, 10);
        uint16_t col     = strtol(arguments[3], (char **)NULL, 10);
        uint16_t keycode = pgm_read_word(&keymaps[layer][row][col]);
        itoa(keycode, keycode_dec, 10);
        itoa(keycode, keycode_hex, 16);
        SEND_STRING("0x");
        send_string(keycode_hex);
        SEND_STRING(" (");
        send_string(keycode_dec);
        SEND_STRING(")\n");
    } else {
#ifdef TERMINAL_HELP
        SEND_STRING("usage: keycode <layer> <row> <col>\n");
#endif
    }
}

void terminal_keymap(void) {
    if (strlen(arguments[1]) != 0) {
        uint16_t layer = strtol(arguments[1], (char **)NULL, 10);
        for (int r = 0; r < MATRIX_ROWS; r++) {
            for (int c = 0; c < MATRIX_COLS; c++) {
                uint16_t keycode = pgm_read_word(&keymaps[layer][r][c]);
                char     keycode_s[8];
                sprintf(keycode_s, "0x%04x,", keycode);
                send_string(keycode_s);
            }
            send_string(newline);
        }
    } else {
#ifdef TERMINAL_HELP
        SEND_STRING("usage: keymap <layer>\n");
#endif
    }
}

void print_cmd_buff(void) {
    /* without the below wait, a race condition can occur wherein the
     buffer can be printed before it has been fully moved */
    wait_ms(250);
    for (int i = 0; i < CMD_BUFF_SIZE; i++) {
        char tmpChar = ' ';
        itoa(i, &tmpChar, 10);
        const char *tmpCnstCharStr = &tmpChar;  // because sned_string wont take a normal char *
        send_string(tmpCnstCharStr);
        SEND_STRING(". ");
        send_string(cmd_buffer[i]);
        SEND_STRING("\n");
    }
}

void flush_cmd_buffer(void) {
    memset(cmd_buffer, 0, CMD_BUFF_SIZE * 80);
    SEND_STRING("Buffer Cleared!\n");
}

stringcase terminal_cases[] = {{"about", terminal_about}, {"help", terminal_help}, {"keycode", terminal_keycode}, {"keymap", terminal_keymap}, {"flush-buffer", flush_cmd_buffer}, {"print-buffer", print_cmd_buff}, {"exit", disable_terminal}};

void terminal_help(void) {
    SEND_STRING("commands available:\n  ");
    for (stringcase *case_p = terminal_cases; case_p != terminal_cases + sizeof(terminal_cases) / sizeof(terminal_cases[0]); case_p++) {
        send_string(case_p->string);
        SEND_STRING(" ");
    }
    send_string(newline);
}

void command_not_found(void) {
    wait_ms(50);  // sometimes buffer isnt grabbed quick enough
    SEND_STRING("command \"");
    send_string(buffer);
    SEND_STRING("\" not found\n");
}

void process_terminal_command(void) {
    // we capture return bc of the order of events, so we need to manually send a newline
    send_string(newline);

    char *  pch;
    uint8_t i = 0;
    pch       = strtok(buffer, " ");
    while (pch != NULL) {
        strcpy(arguments[i], pch);
        pch = strtok(NULL, " ");
        i++;
    }

    bool command_found = false;
    for (stringcase *case_p = terminal_cases; case_p != terminal_cases + sizeof(terminal_cases) / sizeof(terminal_cases[0]); case_p++) {
        if (0 == strcmp(case_p->string, buffer)) {
            command_found = true;
            (*case_p->func)();
            break;
        }
    }

    if (!command_found) command_not_found();

    if (terminal_enabled) {
        strcpy(buffer, "");
        for (int i = 0; i < 6; i++) strcpy(arguments[i], "");
        SEND_STRING(SS_TAP(X_HOME));
        send_string(terminal_prompt);
    }
}
void check_pos(void) {
    if (current_cmd_buffer_pos >= CMD_BUFF_SIZE) {  // if over the top, move it back down to the top of the buffer so you can climb back down...
        current_cmd_buffer_pos = CMD_BUFF_SIZE - 1;
    } else if (current_cmd_buffer_pos < 0) {  //...and if you fall under the bottom of the buffer, reset back to 0 so you can climb back up
        current_cmd_buffer_pos = 0;
    }
}

bool process_terminal(uint16_t keycode, keyrecord_t *record) {
    if (keycode == TERM_ON && record->event.pressed) {
        enable_terminal();
        return false;
    }

    if (terminal_enabled && record->event.pressed) {
        if (keycode == TERM_OFF && record->event.pressed) {
            disable_terminal();
            return false;
        }

        if ((keycode >= QK_MOD_TAP && keycode <= QK_MOD_TAP_MAX) || (keycode >= QK_LAYER_TAP && keycode <= QK_LAYER_TAP_MAX)) {
            keycode = keycode & 0xFF;
        }

        if (keycode < 256) {
            uint8_t str_len;
            char    char_to_add;
            switch (keycode) {
                case KC_ENTER:
                case KC_KP_ENTER:
                    push_to_cmd_buffer();
                    current_cmd_buffer_pos = 0;
                    process_terminal_command();
                    return false;
                    break;
                case KC_ESCAPE:
                    SEND_STRING("\n");
                    enable_terminal();
                    return false;
                    break;
                case KC_BACKSPACE:
                    str_len = strlen(buffer);
                    if (str_len > 0) {
                        buffer[str_len - 1] = 0;
                        return true;
                    } else {
                        TERMINAL_BELL();
                        return false;
                    }
                    break;
                case KC_LEFT:
                    return false;
                    break;
                case KC_RIGHT:
                    return false;
                    break;
                case KC_UP:                                             // 0 = recent
                    check_pos();                                        // check our current buffer position is valid
                    if (current_cmd_buffer_pos <= CMD_BUFF_SIZE - 1) {  // once we get to the top, dont do anything
                        str_len = strlen(buffer);
                        for (int i = 0; i < str_len; ++i) {
                            send_string(SS_TAP(X_BSPACE));  // clear w/e is on the line already
                            // process_terminal(KC_BACKSPACE,record);
                        }
                        strncpy(buffer, cmd_buffer[current_cmd_buffer_pos], 80);

                        send_string(buffer);
                        ++current_cmd_buffer_pos;  // get ready to access the above cmd if up/down is pressed again
                    }
                    return false;
                    break;
                case KC_DOWN:
                    check_pos();
                    if (current_cmd_buffer_pos >= 0) {  // once we get to the bottom, dont do anything
                        str_len = strlen(buffer);
                        for (int i = 0; i < str_len; ++i) {
                            send_string(SS_TAP(X_BSPACE));  // clear w/e is on the line already
                            // process_terminal(KC_BACKSPACE,record);
                        }
                        strncpy(buffer, cmd_buffer[current_cmd_buffer_pos], 79);

                        send_string(buffer);
                        --current_cmd_buffer_pos;  // get ready to access the above cmd if down/up is pressed again
                    }
                    return false;
                    break;
                default:
                    if (keycode <= 58) {
                        char_to_add = 0;
                        if (get_mods() & (MOD_BIT(KC_LEFT_SHIFT) | MOD_BIT(KC_RIGHT_SHIFT))) {
                            char_to_add = shifted_keycode_to_ascii_lut[keycode];
                        } else if (get_mods() == 0) {
                            char_to_add = keycode_to_ascii_lut[keycode];
                        }
                        if (char_to_add != 0) {
                            strncat(buffer, &char_to_add, 1);
                        }
                    }
                    break;
            }
        }
    }
    return true;
}