/*
 * lw12ctl.c
 * Copyright (C) 2017 jpk <jpk@thor>
 *
 * Distributed under terms of the MIT license.
 */

#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <unistd.h>
#include <pwd.h>

#include <readline/readline.h>
#include <readline/history.h>

#include "lw12.h"

#define DebugPrintPos fprintf(stderr, "%s:%d\n", __FILE__, __LINE__)


struct config {
    char *host;
    int port;
};

int exit_interactive_session = 0;
int sockfd = 0;
struct sockaddr_in server_addr;


static void help_lw12_cmd_light() {
    printf("Not enough parameters, choices are:\n");
    printf(" on\n");
    printf(" off\n");
    printf(" set <color> <value>\n\n");
    printf("Color:\n------\nred\ngreen\nblue\nrgb\n\n"
            "The colors red, green and blue require one additional\n"
            "parameter as number between 0 - 255. The `rgb` value\n"
            "has to be given in #RRGGBB hex format.\n");
}


static int lw12_cmd_light(int argc, char *argv[]) {
    if (argc == 0) {
        help_lw12_cmd_light();
        return 1;
    }
    if (strncasecmp(argv[0], "on", strlen(argv[0])) == 0) {
        lw12_sendcmd(sockfd, &server_addr, (char *)LIGHTS_ON);
        lw12_sendcmd(sockfd, &server_addr, (char *)LIGHTS_INIT);
    } else if (strncasecmp(argv[0], "off", strlen(argv[0])) == 0) {
        lw12_sendcmd(sockfd, &server_addr, (char *)LIGHTS_OFF);
    } else if (strncasecmp(argv[0], "help", strlen(argv[0])) == 0) {
        help_lw12_cmd_light();
        return 1;
    } else if (strncasecmp(argv[0], "set", strlen(argv[0])) == 0) {
        if (argc < 3) {
            printf("Not enough parameters, usage:\n"
                    " - set <color> <value>\n\b");
            return 1;
        }

        // todo set color
        unsigned char cmd[LW12_CMD_LENGTH];
        // last char gets not copied?!
        strncpy((char *)cmd, LIGHT_COLOR, LW12_CMD_LENGTH);

        if (strncasecmp(argv[1], "red", strlen(argv[1])) == 0) {
            uint8_t colorvalue = (uint8_t)atoi(argv[2]);
            cmd[4] = (char)colorvalue;
        } else if (strncasecmp(argv[1], "green", strlen(argv[1])) == 0) {
            uint8_t colorvalue = (uint8_t)atoi(argv[2]);
            cmd[5] = (char)colorvalue;
        } else if (strncasecmp(argv[1], "blue", strlen(argv[1])) == 0) {
            uint8_t colorvalue = (uint8_t)atoi(argv[2]);
            cmd[6] = (char)colorvalue;
        } else if (strncasecmp(argv[1], "rgb", strlen(argv[1])) == 0) {
            if (strlen(argv[2]) != 7) {
                printf("Invalid RGB value. Example: #ff138a\n");
                return 1;
            }
            char *pos = argv[2];
            if (*pos == '#')
                pos++;
            int colorvalue = (int)strtol(pos, 0, 16);
            // exchange byte order to match RR GG BB
            colorvalue = (colorvalue & 0x000000ff) << 16
                | (colorvalue & 0x00ff0000) >> 16
                | (colorvalue & 0x0000ff00);
            memcpy(cmd+4, &colorvalue, 4);
        } else {
            printf("Unknown color selected, use: red, green or blue\n");
            return 1;
        }
        // last char gets not copied?!
        cmd[LW12_CMD_LENGTH-1] = '\xef';
        lw12_sendcmd(sockfd, &server_addr, (char *)cmd);
    } else {
        printf("What?!\n");
    }
    return 0;
}

static int lw12_cmd_exit(int argc, char *argv[]) {
    exit_interactive_session = 1;
    return 0;
}

struct lw12_command {
    const char *cmd;
    int (*handler)(int argc, char *argv[]);
    const char *usage;
};

static struct lw12_command lw12_commands[] = {
    {"light", lw12_cmd_light,
        "Control the LED stripe. Turn it on/off and change the colors" },
    {"exit", lw12_cmd_exit,
        "Exit program"},
    {"quit", lw12_cmd_exit,
        "Exit program"}
}; 

int parse_commands(int argc, char *argv[]) {
    struct lw12_command *cmd, *match = NULL;
    int count = 0;
    int ret = 0;

    if (argc < 1)
        return 1;

    cmd = lw12_commands;
    while (cmd->cmd) {
        if (strncasecmp(cmd->cmd, argv[0], strlen(argv[0])) == 0) {
            match = cmd;
            // nessecary?
            if (strcasecmp(cmd->cmd, argv[0]) == 0) {
                count = 1;
                break;
            }
            count++;
        }
        cmd++;
    }
    if (count > 1) {
        printf("Ambiguous commnd '%s'; possible commands:", argv[0]);
        cmd = lw12_commands;
        while (cmd->cmd) {
            if (strncasecmp(cmd->cmd, argv[0], strlen(argv[0])) == 0) {
                printf(" %s", cmd->cmd);
            }
            cmd++;
        }
        printf("\n");
        ret = 1;
    } else if (count == 0) {
        printf("Unknown command '%s'\n", argv[0]);
        ret = 1;
    } else {
        ret = match->handler(argc - 1, &argv[1]);
    }

    return ret;
}

void cmd_loop() {
#define max_args 10
#define buf_size 256
    char *cmd, *cmd_start;
    char *pos;
    char *argv[max_args];
    int argc;

    do {
        cmd = readline("> ");

        if (cmd == NULL)
            break;

        add_history(cmd);

        cmd_start = pos = cmd;
        while (*pos != '\0') {
            // convert \n to separate argument
            if (*pos == '\n') {
                *pos = '\0';
                break;
            }
            pos++;
        }
        argc = 0;
        pos = cmd;
        // count number of arguments
        for (;;) {
            // ignore spaces in the beginning
            while (*pos == ' ')
                pos++;
            if (*pos == '\0')
                break;
            argv[argc] = pos;
            argc++;
            if (argc == max_args)
                break;
            // string arguments
            if (*pos == '"') {
                char *pos2 = strrchr(pos, '"');
                if (pos2)
                    pos = pos2 + 1;
            }
            while (*pos != '\0' && *pos != ' ')
                pos++;
            if (*pos == ' ')
                *pos++ = '\0';
        }

        parse_commands(argc, argv);

        free(cmd);

    } while (!exit_interactive_session);
}

int read_conf(const char *filename, struct config *conf){
    FILE *fd;
    const size_t line_size = 300;
    char *line = (char *)malloc(line_size);
    char *start_pos, *pos;
    char *value = NULL;

    // set default
    conf->host = NULL;
    conf->port = 5000;

    // read config
    fd = fopen(filename, "r");
    if (fd) {
        while (fgets(line, line_size, fd) != NULL) {
            pos = line;
            while (*pos == ' ')
                pos++;
            if (*pos == '#' || *pos == '\n')
                continue;

            start_pos = pos;
            while (*pos != '\0') {
                if (*pos == '\n') {
                    *pos = '\0';
                    break;
                }
                pos++;
            }

            value = strrchr(start_pos, '=');
            start_pos[value - start_pos - 1] = '\0';
            while (*value == ' ' || *value == '=')
                value++;

            if (strncasecmp(start_pos, "host", 4) == 0) {
                size_t param_len = strlen(value);
                conf->host = (char *)malloc(param_len);
                strncpy(conf->host, value, param_len);
            } else if (strncasecmp(start_pos, "port", 4) == 0) {
                conf->port = atoi(value);
            }
        }
    }

    free(line);
    return 0;
}

int main() {
    struct passwd *pw = getpwuid(getuid());
    const char *homedir = pw->pw_dir;
    char confpath[510] = {};
    struct config conf;

    strcat(confpath, homedir);
    strcat(confpath, "/.lw12rc");
    read_conf(confpath, &conf);
    if (conf.host == NULL) {
        fprintf(stderr, "Option 'host' is missing or not set in config.\n");
        return 1;
    }

    rl_bind_key('\t', rl_abort);

    lw12_connect(&sockfd, &server_addr, conf.port, conf.host);
    cmd_loop();
    close(sockfd);

    // Clean config environment
    free(conf.host);

    return 0;
}