/*
 * p1_exec_test.c — проверка EXEC, возврата к родителю и WAIT.
 */

#include <stdio.h>
#include <stdint.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <conio.h>
#include <sprinter.h>
#include "p1_platform.h"

typedef struct {
    int rc;
    int error;
    uint8_t exit_code;
    uint8_t wait_code;
    uint8_t page_w1;
    uint8_t page_w2;
    uint8_t page_w3;
    char cwd[256];
} P1ExecResult;

static P1ExecResult short_result;
static P1ExecResult path_result;
static char cwd_before[256];

static void run_exec_case(const char *label, const char *path,
                          uint8_t path_mode, P1ExecResult *result)
{
    p1_heading(label);
    printf("Calling EXEC: B=%u, path=%s\n", (unsigned)path_mode, path);
    cputs("The child switches to 40x32 and waits for one key.\r\n");
    cputs("After that it returns code 0x5A.\r\n\r\n");
    cputs("Press any key to call EXEC...");
    (void)getkey();

    errno = 0;
    result->rc = p1_exec(path_mode, path);
    result->error = errno;
    result->exit_code = p1_exec_exit_code;
    result->wait_code = p1_wait_code();

    /* Сначала снять страницы, затем исправлять видеорежим и печатать. */
    result->page_w1 = _io_page_w1;
    result->page_w2 = _io_page_w2;
    result->page_w3 = _io_page_w3;

    if (getcwd(result->cwd, sizeof(result->cwd)) == 0) {
        result->cwd[0] = 0;
    }
    (void)settextmode(TEXT_MODE_80x32);
}

static void print_result(const char *name, const P1ExecResult *result)
{
    printf("%s: rc=%d errno=%d exit=%02X wait=%02X pages=%02X/%02X/%02X\n",
           name, result->rc, result->error,
           (unsigned)result->exit_code, (unsigned)result->wait_code,
           (unsigned)result->page_w1, (unsigned)result->page_w2,
           (unsigned)result->page_w3);
    printf("  cwd=%s\n", result->cwd[0] ? result->cwd : "<getcwd failed>");
}

int p1_test_exec(void)
{
    uint8_t before_w1 = _io_page_w1;
    uint8_t before_w2 = _io_page_w2;
    uint8_t before_w3 = _io_page_w3;
    int failed = 0;

    if (getcwd(cwd_before, sizeof(cwd_before)) == 0) {
        p1_heading("EXEC: setup failed");
        printf("getcwd failed: errno=%d\n", errno);
        return -1;
    }

    /* B=0 характеризуем для будущей командной строки. Ошибка этого случая
     * не блокирует PoC: Commander будет передавать явный путь с B=1. */
    run_exec_case("EXEC case 1: short name / PATH",
                  "P1CHILD.EXE", 0, &short_result);

    /* B=1 и явный относительный путь — обязательный случай PoC. */
    run_exec_case("EXEC case 2: explicit path",
                  ".\\P1CHILD.EXE", 1, &path_result);

    p1_heading("EXEC results");
    printf("Parent before: pages=%02X/%02X/%02X cwd=%s\n",
           (unsigned)before_w1, (unsigned)before_w2, (unsigned)before_w3,
           cwd_before);
    print_result("B=0", &short_result);
    print_result("B=1", &path_result);

    if (path_result.rc != 0 || path_result.exit_code != 0x5A ||
        path_result.wait_code != 0x5A) {
        puts("Required B=1 EXEC result is incorrect.");
        failed++;
    }
    if (path_result.page_w1 != before_w1 || path_result.page_w2 != before_w2 ||
        path_result.page_w3 != before_w3) {
        puts("Parent window mapping was not restored.");
        failed++;
    }
    if (strcmp(path_result.cwd, cwd_before) != 0) {
        puts("Parent CWD changed after child.");
        failed++;
    }

    if (short_result.rc != 0) {
        puts("NOTE: B=0 short-name lookup failed; explicit B=1 remains usable.");
    }

    printf("EXEC checks failed: %u\n", (unsigned)failed);
    return failed ? -1 : 0;
}