#include "commander.h"
#include "aliases.h"
#include "shell_utils.h"
#include <stdarg.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define CMD_BUF_LEN 8192
#define OUT_BUF_LEN 4096

internal inline CMDError build_command_from_args(char *cmd, u64 buf_len, va_list args);
internal inline CMDResult execute_command(const char *cmd, CMDOutHandling out_handling, char *out_buf,
                                          u64 buf_size);
internal inline CMDError get_command_output(FILE *fp, CMDOutHandling out_handling, char *out_buf,
                                            u64 buf_size);
extern CMDError get_output_status(FILE *fp, i32 *status_out);

CMDResult run_command(CMDOutHandling out_handling, char *out_buf, u64 buf_size, ...) {
  va_list args;
  va_start(args, buf_size);

  char cmd[CMD_BUF_LEN] = {0};
  CMDError err = build_command_from_args(cmd, CMD_BUF_LEN, args);
  if (err > SHELL_ERR_NO_ERROR) {
    va_end(args);
    return CMD_NO_EXIT(err);
  }

  va_end(args);

  return execute_command(cmd, out_handling, out_buf, buf_size);
}

internal inline CMDError build_command_from_args(char *cmd, u64 buf_len,
                                                 va_list args) {
  u64 size = 0;
  u64 arg_len = 0;

  const char *arg = va_arg(args, const char *);
  while (arg) {
    arg_len = strlen(arg);
    if (arg_len >= buf_len - size) {
      return SHELL_ERR_CMD_BUF_FULL;
    }

    strcat(cmd, arg);
    cmd[size + arg_len] = ' ';

    size += arg_len + 1;

    arg = va_arg(args, const char *);
  }

  return SHELL_ERR_NO_ERROR;
}

internal inline CMDResult execute_command(const char *cmd,
                                          CMDOutHandling out_handling,
                                          char *out_buf, u64 buf_size) {
  FILE *fp = wapp_shell_utils_popen(cmd, "r");
  if (!fp) {
    return CMD_NO_EXIT(SHELL_ERR_PROC_START_FAIL);
  }

  CMDResult output;

  CMDError err = get_command_output(fp, out_handling, out_buf, buf_size);
  if (err > SHELL_ERR_NO_ERROR) {
    output = CMD_NO_EXIT(err);
    goto EXECUTE_COMMAND_CLOSE;
  }

  i32 st = EXIT_SUCCESS;
  err = get_output_status(fp, &st);
  if (err > SHELL_ERR_NO_ERROR) {
    output = CMD_NO_EXIT(err);
    goto EXECUTE_COMMAND_CLOSE;
  }

  // Process is already closed in get_output_status
  fp = NULL;

  output = (CMDResult){
      .exited = true,
      .exit_code = st,
      .error = SHELL_ERR_NO_ERROR,
  };

EXECUTE_COMMAND_CLOSE:
  if (fp) {
    wapp_shell_utils_pclose(fp);
  }
  return output;
}

internal inline CMDError get_command_output(FILE *fp,
                                            CMDOutHandling out_handling,
                                            char *out_buf, u64 buf_size) {
  char out[OUT_BUF_LEN] = {0};
  u64 max_out_length = OUT_BUF_LEN - 1;

  u64 buf_filled = 0;
  while (fgets(out, (i32)max_out_length, fp)) {
    if (out_handling == SHELL_OUTPUT_CAPTURE && out_buf != NULL) {
      buf_filled += strlen(out);
      if (buf_filled >= buf_size) {
        return SHELL_ERR_OUT_BUF_FULL;
      }

      strcat(out_buf, out);
    } else if (out_handling == SHELL_OUTPUT_PRINT) {
      printf("%s", out);
    }
  }

  return SHELL_ERR_NO_ERROR;
}