#include "app_cmd_parser.h"
#include <string.h>
#include <ctype.h>

static int find_payload_pos(const char *line)
{
    const char *p = strchr(line, ':');
    if (!p) return -1;
    return (int)(p - line + 1);
}

static uint8_t hex_nibble(char c)
{
    c = (char)toupper((unsigned char)c);

    if (c >= '0' && c <= '9') return (uint8_t)(c - '0');
    if (c >= 'A' && c <= 'F') return (uint8_t)(10 + (c - 'A'));

    return 0xFFu;
}

static int hex_pair_to_u8(char hi, char lo, uint8_t *out)
{
    uint8_t h;
    uint8_t l;

    if (!out) return 0;

    h = hex_nibble(hi);
    l = hex_nibble(lo);

    if (h == 0xFFu || l == 0xFFu) return 0;

    *out = (uint8_t)((h << 4) | l);
    return 1;
}

int app_cmd_parse_line(app_cmd_src_t src, const char *line, app_job_t *job)
{
    int payload_pos;
    int len;
    int pos;
    unsigned int k;

    if (!line || !job) return 0;

    memset(job, 0, sizeof(*job));
    job->src = src;
    job->check_on = 1u;

    strncpy(job->line, line, sizeof(job->line) - 1);
    job->line[sizeof(job->line) - 1] = '\0';

    len = (int)strlen(line);

    /* x? ?? ? ?? local exec */
    if (line[0] != 'x' && line[0] != 'X') {
        job->type = APP_JOB_LOCAL_EXEC;
        return 1;
    }

    payload_pos = find_payload_pos(line);
    if (payload_pos < 0) {
        job->type = APP_JOB_FORWARD_LINE;
        return 1;
    }

    /* ?? ?? ??: xNNc_...:payload */
    if (len < payload_pos) return 0;
    if (!isdigit((unsigned char)line[1]) || !isdigit((unsigned char)line[2])) return 0;

    job->addr = (uint8_t)((line[1] - '0') * 10 + (line[2] - '0'));
    job->mode = (char)toupper((unsigned char)line[3]);

    /* ?? CAL? ?? */
    if (job->mode != 'C') return 0;

    /* xNNc_001101:... ?? channel = 001 */
    if (payload_pos >= 8 &&
        isdigit((unsigned char)line[5]) &&
        isdigit((unsigned char)line[6]) &&
        isdigit((unsigned char)line[7])) {
        job->channel = (uint8_t)((line[5] - '0') * 100 +
                                 (line[6] - '0') * 10 +
                                 (line[7] - '0'));
    }

    /* ?? ??? */
    if (payload_pos >= 11) {
        job->hash_on   = (uint8_t)(line[8]  == '1');
        job->anaout_on = (uint8_t)(line[9]  == '1');
        job->check_on  = (uint8_t)(line[10] == '1');
    }

    pos = payload_pos;
    if (pos + 1 >= len) return 0;

    /* ow / owt */
    if ((line[pos] == 'o' || line[pos] == 'O') &&
        (line[pos + 1] == 'w' || line[pos + 1] == 'W')) {
        job->type = APP_JOB_PROTO_OW;
        pos += 2;

        if (pos < len && (line[pos] == 't' || line[pos] == 'T')) {
            job->proto = APP_PROTO_OWIT;
            pos++;
        } else {
            job->proto = APP_PROTO_OWIW;
        }
    }
    /* or */
    else if ((line[pos] == 'o' || line[pos] == 'O') &&
             (line[pos + 1] == 'r' || line[pos + 1] == 'R')) {
        job->type = APP_JOB_PROTO_OR;
        job->proto = APP_PROTO_OWIR;
        pos += 2;
    }
    else {
        job->type = APP_JOB_FORWARD_LINE;
        return 1;
    }

    if (pos < len && (line[pos] == '_' || line[pos] == ':')) pos++;

    if (pos + 1 >= len) return 0;
    if (!hex_pair_to_u8(line[pos], line[pos + 1], &job->id)) return 0;
    pos += 2;

    if (pos + 2 >= len ||
        !isdigit((unsigned char)line[pos]) ||
        !isdigit((unsigned char)line[pos + 1]) ||
        !isdigit((unsigned char)line[pos + 2])) {
        return 0;
    }

    job->len = (uint16_t)(100 * (line[pos] - '0') +
                           10 * (line[pos + 1] - '0') +
                                (line[pos + 2] - '0'));
    pos += 3;

    if (job->type == APP_JOB_PROTO_OW) {
        if (job->len == 0u || job->len > APP_JOB_PAYLOAD_MAX) return 0;
        if (pos + ((int)job->len * 2) > len) return 0;

        for (k = 0; k < job->len; k++) {
            if (!hex_pair_to_u8(line[pos + (int)(2 * k)],
                                line[pos + (int)(2 * k + 1)],
                                &job->payload[k])) {
                return 0;
            }
        }

        pos += (int)job->len * 2;

        /* payload ?? ?? ??? ??? ?? */
        if (pos != len) return 0;
    }
    else {
        /* OR(read)? ??? ?? payload? ??? ? */
        if (job->len == 0u || job->len > APP_JOB_PAYLOAD_MAX) return 0;
        if (pos != len) return 0;
    }

    return 1;
}