/** ------------------------------------------------------------
 * File          : xy.h
 * License       : MIT
 * Authors       : Aoran Zeng <ccmywish@qq.com>
 * Created on    : <2023-08-28>
 * Last modified : <2024-04-18>
 *
 * xy:
 *
 *   y = f(x)
 *
 *   Corss-Platform C utilities for CLI applications in Ruby flavor
 *
 *   该文件采用 MIT 许可证，请查阅 LICENSE.txt 文件
 * ------------------------------------------------------------*/

#ifndef XY_H
#define XY_H

#define XY_Version      "v0.1.1-2024/04/18"
#define XY_Maintain_URL "https://gitee.com/RubyMetric/chsrc/blob/main/xy.h"

#include <assert.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

// #define NDEBUG

#ifdef _WIN32
#define xy_on_windows true
#define xy_on_linux false
#define xy_on_macos false
#define xy_on_bsd false
#define xy_os_devnull "nul"
#include <windows.h>
#define xy_useutf8() SetConsoleOutputCP (65001)

#elif defined(__linux__) || defined(__linux)
#define xy_on_windows false
#define xy_on_linux true
#define xy_on_macos false
#define xy_on_bsd false
#define xy_os_devnull "/dev/null"
#define xy_useutf8()

#elif defined(__APPLE__)
#define xy_on_windows false
#define xy_on_linux false
#define xy_on_macos true
#define xy_on_bsd false
#define xy_os_devnull "/dev/null"
#define xy_useutf8()

#elif defined(__OpenBSD__) || defined(__NetBSD__) || defined(__FreeBSD__)
#define xy_on_windows false
#define xy_on_linux false
#define xy_on_macos false
#define xy_on_bsd true
#define xy_os_devnull "/dev/null"
#define xy_useutf8()
#endif

void
putf (double n)
{
  printf ("%f\n", n);
}
void
puti (long long n)
{
  printf ("%lld\n", n);
}
void
putb (bool n)
{
  if (n)
    puts ("true");
  else
    puts ("false");
}
void
print (char *s)
{
  printf ("%s", s);
}
void
println (char *s)
{
  printf ("%s\n", s);
}

#define xy_arylen(x) (sizeof (x) / sizeof (x[0]))

#define assert_str(a, b) assert (xy_streql ((a), (b)))

static inline void *
xy_malloc0 (size_t size)
{
  void *ptr = malloc (size);
  memset (ptr, 0, size);
  return ptr;
}

#define XY_Log_Info 00001
#define XY_Log_Success 00001 << 1
#define XY_Log_Warn 00001 << 2
#define XY_Log_Error 00001 << 3

#define xy_success(str) _xy_log (XY_Log_Success, str)
#define xy_info(str) _xy_log (XY_Log_Info, str)
#define xy_warn(str) _xy_log (XY_Log_Warn, str)
#define xy_error(str) _xy_log (XY_Log_Error, str)

static void
_xy_log (int level, const char *str)
{
  char *color_fmt_str = NULL;

  bool to_stderr = false;

  if (level & XY_Log_Info)
    {
      color_fmt_str = "\033[34m%s\033[0m"; // 蓝色
    }
  else if (level & XY_Log_Success)
    {
      color_fmt_str = "\033[32m%s\033[0m"; // 绿色
    }
  else if (level & XY_Log_Warn)
    {
      color_fmt_str = "\033[33m%s\033[0m\n"; // 黄色
      to_stderr = true;
    }
  else if (level & XY_Log_Error)
    {
      color_fmt_str = "\033[31m%s\033[0m\n"; // 红色
      to_stderr = true;
    }
  else
    {
      // xy_assert ("CAN'T REACH!");
    }

  // -2 把中间%s减掉
  size_t len = strlen (color_fmt_str) - 2;
  char *buf = malloc (strlen (str) + len + 1);

  sprintf (buf, color_fmt_str, str);
  if (to_stderr)
    {
      fprintf (stderr, "%s", buf);
    }
  else
    {
      puts (buf);
    }
  free (buf);
}

/**
 * 将str中所有的pat字符串替换成replace，返回一个全新的字符串
 */
static char *
xy_str_gsub (const char *str, const char *pat, const char *replace)
{
  size_t replace_len = strlen (replace);
  size_t pat_len = strlen (pat);

  int unit = replace_len - pat_len;
  if (unit <= 0)
    unit = 0;

  size_t len = strlen (str);

  const char *cur = str;
  int count = 0;

  while (cur < str + len)
    {
      char *fnd = strstr (cur, pat);
      if (fnd)
        {
          count++;
          cur = fnd + pat_len;
        }
      else
        break;
    }
  // puti(count); DEBUG 匹配次数

  char *ret = malloc (unit * count + len + 1);
  char *retcur = ret;

  cur = str;
  while (cur < str + len)
    {
      char *fnd = strstr (cur, pat);
      if (fnd)
        {
          ptrdiff_t diff = fnd - cur;
          strncpy (retcur, cur, diff);
          cur = fnd + pat_len;

          retcur += diff;
          strcpy (retcur, replace);
          retcur += replace_len;
        }
      else
        break;
    }
  strcpy (retcur, cur);

  return ret;
}

static char *
xy_2strjoin (const char *str1, const char *str2)
{
  size_t len = strlen (str1);
  size_t size = len + strlen (str2) + 1;
  char *ret = malloc (size);
  strcpy (ret, str1);
  strcpy (ret + len, str2);
  return ret;
}

static char *
xy_strjoin (unsigned int count, ...)
{
  size_t al_fixed = 128;
  char *ret = calloc (1, al_fixed);
  // 已分配次数
  int al_times = 1;
  // 当前已分配量
  size_t al_cur = al_fixed;

  const char *str = NULL;
  // 需要分配的量
  size_t al_need = 0;
  // 用于 strcpy() 到 ret 的哪个位置
  char *cur = ret + 0;

  va_list args;
  va_start (args, count);

  for (int i = 0; i < count; i++)
    {
      // 是否需要重新分配
      bool need_realloc = false;

      str = va_arg (args, const char *);
      al_need += strlen (str);
      while (al_need > al_cur)
        {
          al_times += 1;
          al_cur = al_times * al_fixed;
          need_realloc = true;
        }
      // printf("al_times %d, al_need %zd, al_cur %zd\n", al_times, al_need,
      // al_cur);
      if (need_realloc)
        {
          ptrdiff_t diff = cur - ret;
          ret = realloc (ret, al_cur);
          cur = ret + diff;
        }
      if (NULL == ret)
        {
          xy_error ("xy: No availble memory!");
          return NULL;
        }
      strcpy (cur, str);
      // puts(ret);
      cur += strlen (str);
    }
  va_end (args);

  *cur = '\0';
  return ret;
}

static char *
xy_strdup (const char *str)
{
  size_t len = strlen (str);
  char *new = xy_malloc0 (len + 1);
  strcpy (new, str);
  return new;
}

#define XY_Str_Bold 1
#define XY_Str_Faint 2
#define XY_Str_Italic 3
#define XY_Str_Underline 4
#define XY_Str_Blink 5
#define XY_Str_Cross 9

#define xy_str_to_bold(str) _xy_str_to_terminal_style (XY_Str_Bold, str)
#define xy_str_to_faint(str) _xy_str_to_terminal_style (XY_Str_Faint, str)
#define xy_str_to_italic(str) _xy_str_to_terminal_style (XY_Str_Italic, str)
#define xy_str_to_underline(str)                                              \
  _xy_str_to_terminal_style (XY_Str_Underline, str)
#define xy_str_to_blink(str) _xy_str_to_terminal_style (XY_Str_Blink, str)
#define xy_str_to_cross(str) _xy_str_to_terminal_style (XY_Str_Cross, str)

#define XY_Str_Red 31
#define XY_Str_Green 32
#define XY_Str_Yellow 33
#define XY_Str_Blue 34
#define XY_Str_Magenta 35
#define XY_Str_Cyan 36

#define xy_str_to_red(str) _xy_str_to_terminal_style (XY_Str_Red, str)
#define xy_str_to_green(str) _xy_str_to_terminal_style (XY_Str_Green, str)
#define xy_str_to_yellow(str) _xy_str_to_terminal_style (XY_Str_Yellow, str)
#define xy_str_to_blue(str) _xy_str_to_terminal_style (XY_Str_Blue, str)
#define xy_str_to_magenta(str) _xy_str_to_terminal_style (XY_Str_Magenta, str)
#define xy_str_to_purple xy_str_to_magenta
#define xy_str_to_cyan(str) _xy_str_to_terminal_style (XY_Str_Cyan, str)

static char *
_xy_str_to_terminal_style (int style, const char *str)
{
  char *color_fmt_str = NULL;

  switch (style)
    {
    case XY_Str_Red:
      color_fmt_str = "\e[31m%s\e[0m"; break;
    case XY_Str_Green:
      color_fmt_str = "\e[32m%s\e[0m"; break;
    case XY_Str_Yellow:
      color_fmt_str = "\e[33m%s\e[0m"; break;
    case XY_Str_Blue:
      color_fmt_str = "\e[34m%s\e[0m"; break;
    case XY_Str_Magenta:
      color_fmt_str = "\e[35m%s\e[0m"; break;
    case XY_Str_Cyan:
      color_fmt_str = "\e[36m%s\e[0m"; break;
    case XY_Str_Bold:
      color_fmt_str = "\e[1m%s\e[0m"; break;
    case XY_Str_Faint:
      color_fmt_str = "\e[2m%s\e[0m"; break;
    case XY_Str_Italic:
      color_fmt_str = "\e[3m%s\e[0m"; break;
    case XY_Str_Underline:
      color_fmt_str = "\e[4m%s\e[0m"; break;
    case XY_Str_Blink:
      color_fmt_str = "\e[5m%s\e[0m"; break;
    case XY_Str_Cross:
      color_fmt_str = "\e[9m%s\e[0m"; break;
    }

  // -2 把中间%s减掉
  size_t len = strlen (color_fmt_str) - 2;
  char *buf = malloc (strlen (str) + len + 1);
  sprintf (buf, color_fmt_str, str);
  return buf;
}

static bool
xy_streql (const char *str1, const char *str2)
{
  return strcmp (str1, str2) == 0 ? true : false;
}

static char *
xy_str_to_quietcmd (const char *cmd)
{
  char *ret = NULL;
#ifdef _WIN32
  ret = xy_2strjoin (cmd, " >nul 2>nul ");
#else
  ret = xy_2strjoin (cmd, " 1>/dev/null 2>&1 ");
#endif
  return ret;
}

static bool
xy_str_end_with (const char *str, const char *suffix)
{
  size_t len1 = strlen (str);
  size_t len2 = strlen (suffix);

  if (0 == len2)
    return true; // 空字符串直接返回
  if (len1 < len2)
    return false;

  const char *cur1 = str + len1 - 1;
  const char *cur2 = suffix + len2 - 1;

  for (int i = 0; i < len2; i++)
    {
      if (*cur1 != *cur2)
        return false;
      cur1--;
      cur2--;
    }
  return true;
}

static bool
xy_str_start_with (const char *str, const char *prefix)
{
  size_t len1 = strlen (str);
  size_t len2 = strlen (prefix);

  if (0 == len2)
    return true; // 空字符串直接返回
  if (len1 < len2)
    return false;

  const char *cur1 = str;
  const char *cur2 = prefix;

  for (int i = 0; i < len2; i++)
    {
      if (*cur1 != *cur2)
        return false;
      cur1++;
      cur2++;
    }
  return true;
}

static char *
xy_str_delete_prefix (const char *str, const char *prefix)
{
  char *new = xy_strdup (str);
  bool yes = xy_str_start_with (str, prefix);
  if (!yes)
    return new;

  size_t len = strlen (prefix);
  char *cur = new + len;
  return cur;
}

static char *
xy_str_delete_suffix (const char *str, const char *suffix)
{
  char *new = xy_strdup (str);
  bool yes = xy_str_end_with (str, suffix);
  if (!yes)
    return new;

  size_t len1 = strlen (str);
  size_t len2 = strlen (suffix);
  char *cur = new + len1 - len2;
  *cur = '\0';
  return new;
}

static char *
xy_str_strip (const char *str)
{
  char *new = xy_strdup (str);

  while (strchr ("\n\r\v\t\f ", new[0]))
    {
      new += 1;
    }

  size_t len = strlen (new);

  char *last = new + len - 1;

  while (strchr ("\n\r\v\t\f ", *last))
    {
      *last = '\0';
      last -= 1;
    }
  return new;
}

/**
 * 执行cmd，返回其最后某行输出结果
 *
 * @param  cmd   要执行的命令
 * @param   n    命令打印的结果行，0 表示最后一行，n (n>0) 表示第n行
 * @param  func  对读取的行执行函数
 *
 * @note 返回的字符串最后面可能有换行符号
 */
static char *
xy_getcmd (const char *cmd, unsigned long n, void (*func) (const char *))
{
  const int size = 512;
  char *buf = (char *)malloc (size);

  FILE *stream = popen (cmd, "r");
  if (stream == NULL)
    {
      fprintf (stderr, "xy: 命令执行失败\n");
      return NULL;
    }

  char *ret = NULL;
  unsigned long count = 0;

  while (true)
    {
      if (NULL == fgets (buf, size, stream))
        break;
      ret = buf;
      count += 1;
      if (n == count)
        break;
      if (func)
        {
          func (buf);
        }
    }

  pclose (stream);
  return ret;
}

#define xy_os_home _xy_os_home ()
static char *
_xy_os_home ()
{
  char *home = NULL;
  if (xy_on_windows)
    home = getenv ("USERPROFILE");
  else
    home = getenv ("HOME");
  return home;
}

#define xy_win_powershell_profile _xy_win_powershell_profile ()
#define xy_win_powershellv5_profile _xy_win_powershellv5_profile ()
static char *
_xy_win_powershell_profile ()
{
  return xy_2strjoin (
      xy_os_home, "\\Documents\\PowerShell\\Microsoft.PowerShell_profile.ps1");
}

char *
_xy_win_powershellv5_profile ()
{
  return xy_2strjoin (
      xy_os_home,
      "\\Documents\\WindowsPowerShell\\Microsoft.PowerShell_profile.ps1");
}

/**
 * @note Windows上，`path` 不要夹带变量名，因为最终 access() 不会帮你转换
 */
static bool
xy_file_exist (const char *path)
{
  const char *newpath = path;
  if (xy_on_windows)
    {
      if (xy_str_start_with (path, "~"))
        {
          newpath = xy_2strjoin (xy_os_home, path + 1);
        }
    }
  return access (newpath, 0) ? false : true;
}

/**
 * 该函数即使在非Windows下也可调用，作用是删除路径左右两边多出来的空白符
 */
static char *
xy_uniform_path (const char *path)
{
  char *new = xy_str_strip (path); // 防止开发者多写了空白符

  // 这个函数仅在Windows上才进行替换
  if (xy_on_windows)
    {
      if (xy_str_start_with (new, "~/"))
        {
          // 或 %USERPROFILE%
          new = xy_strjoin (3, xy_os_home, "\\",
                            xy_str_delete_prefix (new, "~/"));
        }
      new = xy_str_gsub (new, "/", "\\");
    }

  return new;
}

static char *
xy_parent_dir (const char *path)
{
  char *dir = xy_uniform_path (path);
  char *last = NULL;
  if (xy_on_windows)
    {
      last = strrchr (dir, '\\');
      *last = '\0';
    }
  else
    {
      last = strrchr (dir, '/');
      *last = '\0';
    }
  return dir;
}

#endif