#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <errno.h>

#include <patty/bin/if.h>

struct context {
    patty_error *err;

    char *name;
    patty_ax25_addr addr;
};

enum mode {
    MODE_NONE,
    MODE_IFNAME,
    MODE_IFOPTS,
    MODE_IFADDR,
    MODE_KISS,
    MODE_BAUD,
    MODE_FLOW
};

static patty_ax25_if *create_kiss(struct context *ctx, int argc, char **argv) {
    enum mode mode = MODE_KISS;

    patty_kiss_tnc_info info;

    int i;

    memset(&info, '\0', sizeof(info));

    if (argc == 0) {
        patty_error_fmt(ctx->err, "Too few parameters for 'kiss' interface");

        goto error_invalid;
    }

    for (i=0; i<argc; i++) {
        switch (mode) {
            case MODE_KISS:
                info.flags |= PATTY_KISS_TNC_DEVICE;
                info.device = argv[i];

                mode = MODE_IFOPTS;

                break;

            case MODE_IFOPTS:
                if (strcmp(argv[i], "baud") == 0) {
                    mode = MODE_BAUD;
                } else if (strcmp(argv[i], "flow") == 0) {
                    mode = MODE_FLOW;
                } else {
                    patty_error_fmt(ctx->err, "Invalid parameter '%s'",
                        argv[i]);
                }

                break;

            case MODE_BAUD:
                if (!(argv[i][0] >= '0' && argv[i][0] <= '9')) {
                    patty_error_fmt(ctx->err, "Invalid baud rate '%s'",
                        argv[i]);

                    goto error_invalid;
                }

                info.flags |= PATTY_KISS_TNC_BAUD;
                info.baud   = atoi(argv[i]);

                mode = MODE_IFOPTS;

                break;

            case MODE_FLOW:
                if (strcmp(argv[i], "crtscts") == 0) {
                    info.flags |= PATTY_KISS_TNC_FLOW;
                    info.flow   = PATTY_KISS_TNC_FLOW_CRTSCTS;
                } else if (strcmp(argv[i], "xonxoff") == 0) {
                    info.flags |= PATTY_KISS_TNC_FLOW;
                    info.flow   = PATTY_KISS_TNC_FLOW_XONXOFF;
                } else {
                    patty_error_fmt(ctx->err, "Invalid flow control '%s'",
                        argv[i]);

                    goto error_invalid;
                }

                mode = MODE_IFOPTS;

                break;

            default:
                break;
        }
    }

    return patty_ax25_if_new( ctx->name,
                             &ctx->addr,
                             patty_kiss_tnc_driver(),
                             &info);

error_invalid:
    return NULL;
}

struct if_type {
    const char *name;
    patty_ax25_if *(*func)(struct context *ctx, int argc, char **argv);
};

struct if_type if_types[] = {
    { "kiss", create_kiss },
    {  NULL,  NULL        }
};

patty_ax25_if *patty_bin_if_create(int argc, char **argv, patty_error *e) {
    enum mode mode = MODE_NONE;

    struct context ctx = {
        .err  = e,
        .name = NULL
    };

    int i;

    patty_error_clear(e);

    memset(&ctx.addr, '\0', sizeof(ctx.addr));

    for (i=0; i<argc; i++) {
        switch (mode) {
            case MODE_NONE:
                if (strcmp(argv[i], "if") != 0) {
                    patty_error_fmt(e, "Unexpected start of expression '%s'",
                        argv[i]);

                    goto error_invalid;
                } else {
                    mode = MODE_IFNAME;
                }

                break;

            case MODE_IFNAME:
                ctx.name = argv[i];

                mode = MODE_IFOPTS;

                break;

            case MODE_IFOPTS:
                if (strcmp(argv[i], "ax25") == 0) {
                    mode = MODE_IFADDR;
                } else {
                    int t;

                    for (t=0; if_types[t].name; t++) {
                        if (strcmp(if_types[t].name, argv[i]) == 0) {
                            return if_types[t].func(&ctx,
                                                    argc - i - 1,
                                                    argv + i + 1);
                        }
                    }

                    patty_error_fmt(e, "Invalid parameter '%s'", argv[i]);

                    goto error_invalid;
                }

                break;

            case MODE_IFADDR:
                if (patty_ax25_pton(argv[i], &ctx.addr) < 0) {
                    patty_error_fmt(e, "Invalid AX.25 address '%s': %s",
                        argv[i], strerror(errno));

                    goto error_invalid;
                }

                mode = MODE_IFOPTS;

                break;

            default:
                break;
        }
    }

    patty_error_fmt(e, "Media type not provided");

error_invalid:
    return NULL;
}