#include "cst_agent.h"
#include "os_compat.h"

#include <curl/curl.h>
#include <getopt.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifdef _WIN32
#include <direct.h>
#else
#include <unistd.h>
#endif

static void usage(const char *argv0) {
  fprintf(stderr,
          "Usage: %s [--workspace DIR] [--session FILE] [--api-base URL]\n"
          "          [--api-key KEY] [--model NAME] [--headless]\n"
          "          [--prompt TEXT] [--demo-ctl] [--ask-key]\n"
          "\n"
          "Defaults: api-base=https://api.minimax.cn/v1 model=MiniMax-M2.7\n"
          "Session: <workspace>/.agent/sessions/<id>.jsonl (CURRENT tracked)\n"
          "API key: CST_API_KEY / OPENAI_API_KEY / MINIMAX_API_KEY\n"
          "Base:    CST_API_BASE / OPENAI_BASE_URL (OpenAI-compatible …/v1)\n"
          "Model:   CST_MODEL / OPENAI_MODEL\n"
          "Also:    CST_MODELS, CST_AUTO_APPROVE=1, CST_SHELL, CST_EXE_DIR\n"
          "TUI: /new /session /model /compact /details /help\n"
          "     Enter send · Ctrl+N newline · ↑↓ history · Esc cancel\n"
          "     busy Enter queues · tool perm y/n/a=always · wheel scroll\n",
          argv0);
}

static int g_ready;
static ctl_tool_call_t g_call;

static void demo_on_ev(const ctl_event_t *ev, void *ud) {
  (void)ud;
  if (ev->type == CTL_EV_TEXT)
    fwrite(ev->text, 1, ev->text_len, stdout);
  if (ev->type == CTL_EV_CALL_READY) {
    snprintf(g_call.id, sizeof(g_call.id), "%s", ev->call->id);
    snprintf(g_call.name, sizeof(g_call.name), "%s", ev->call->name);
    for (int i = 0; i < g_call.nargs; i++) {
      free(g_call.args[i].value);
      g_call.args[i].value = NULL;
    }
    g_call.nargs = 0;
    for (int i = 0; i < ev->call->nargs; i++) {
      snprintf(g_call.args[i].key, sizeof(g_call.args[i].key), "%s",
               ev->call->args[i].key);
      g_call.args[i].value_len = ev->call->args[i].value_len;
      g_call.args[i].value = malloc(ev->call->args[i].value_len + 1);
      memcpy(g_call.args[i].value, ev->call->args[i].value,
             ev->call->args[i].value_len);
      g_call.args[i].value[ev->call->args[i].value_len] = 0;
      g_call.nargs++;
    }
    g_ready = 1;
  }
}

static int demo_ctl_impl(const char *workspace) {
  printf("=== demo CTL (byte-at-a-time feed) ===\n");
  g_ready = 0;
  memset(&g_call, 0, sizeof(g_call));
  ctl_parser_t *p = ctl_parser_create(demo_on_ev, NULL);
  const char *stream =
      "Reading README.\n"
      "call t1 read_file\n"
      "arg path 9\n"
      "README.md"
      "end\n";
  for (size_t i = 0; stream[i]; i++)
    ctl_parser_feed(p, &stream[i], 1);
  if (ctl_parser_finish(p) != CTL_OK || !g_ready) {
    fprintf(stderr, "demo: CTL failed\n");
    ctl_parser_destroy(p);
    return 1;
  }
  printf("\npending_peak=%zu\n", ctl_parser_pending_peak(p));
  ctl_parser_destroy(p);

  cst_tool_result_t r = {0};
  cst_tool_dispatch(workspace, &g_call, &r);
  printf("[tool result exit=%d]\n%.*s\n", r.exit_code, (int)r.out_len,
         r.out ? r.out : "");
  cst_tool_result_free(&r);
  for (int i = 0; i < g_call.nargs; i++)
    free(g_call.args[i].value);
  return 0;
}

int main(int argc, char **argv) {
  os_set_prog_path(argv[0]);
  curl_global_init(CURL_GLOBAL_DEFAULT);

  cst_agent_config_t cfg = {0};
  char cwd[4096];
#ifdef _WIN32
  if (!_getcwd(cwd, (int)sizeof(cwd)))
#else
  if (!getcwd(cwd, sizeof(cwd)))
#endif
    snprintf(cwd, sizeof(cwd), ".");
  snprintf(cfg.workspace_root, sizeof(cfg.workspace_root), "%s", cwd);
  cfg.session_path[0] = 0; /* filled after workspace opts via .agent/store */
  /* OpenAI-compatible base URL aliases */
  const char *env_base = getenv("CST_API_BASE");
  if (!env_base || !env_base[0])
    env_base = getenv("OPENAI_BASE_URL");
  if (!env_base || !env_base[0])
    env_base = getenv("OPENAI_API_BASE");
  const char *env_model = getenv("CST_MODEL");
  if (!env_model || !env_model[0])
    env_model = getenv("OPENAI_MODEL");
  snprintf(cfg.api_base, sizeof(cfg.api_base), "%s",
           env_base && env_base[0] ? env_base : "https://api.minimax.cn/v1");
  cfg.api_key[0] = 0;
  snprintf(cfg.model, sizeof(cfg.model), "%s",
           env_model && env_model[0] ? env_model : "MiniMax-M2.7");
  cfg.headless = 0;
  cfg.confirm_shell = 1;
  cfg.confirm_write = 1;
  cfg.auto_approve = 0;
  if (getenv("CST_AUTO_APPROVE"))
    cfg.auto_approve = 1;

  int do_demo = 0;
  int force_ask_key = 0;
  int session_explicit = 0;
  const char *prompt = NULL;
  int key_from_cli = 0;

  static struct option opts[] = {
      {"workspace", required_argument, 0, 'w'},
      {"session", required_argument, 0, 's'},
      {"api-base", required_argument, 0, 'b'},
      {"api-key", required_argument, 0, 'k'},
      {"model", required_argument, 0, 'm'},
      {"headless", no_argument, 0, 'H'},
      {"prompt", required_argument, 0, 'p'},
      {"demo-ctl", no_argument, 0, 'd'},
      {"ask-key", no_argument, 0, 'a'},
      {"help", no_argument, 0, 'h'},
      {0, 0, 0, 0}};
  int c;
  while ((c = getopt_long(argc, argv, "w:s:b:k:m:Hp:dah", opts, NULL)) != -1) {
    switch (c) {
    case 'w':
      snprintf(cfg.workspace_root, sizeof(cfg.workspace_root), "%s", optarg);
      break;
    case 's':
      snprintf(cfg.session_path, sizeof(cfg.session_path), "%s", optarg);
      session_explicit = 1;
      break;
    case 'b':
      snprintf(cfg.api_base, sizeof(cfg.api_base), "%s", optarg);
      break;
    case 'k':
      snprintf(cfg.api_key, sizeof(cfg.api_key), "%s", optarg);
      key_from_cli = 1;
      break;
    case 'm':
      snprintf(cfg.model, sizeof(cfg.model), "%s", optarg);
      break;
    case 'H':
      cfg.headless = 1;
      break;
    case 'p':
      prompt = optarg;
      break;
    case 'd':
      do_demo = 1;
      break;
    case 'a':
      force_ask_key = 1;
      break;
    case 'h':
      usage(argv[0]);
      curl_global_cleanup();
      return 0;
    default:
      usage(argv[0]);
      curl_global_cleanup();
      return 1;
    }
  }

  /* trim trailing slash on api_base */
  size_t alen = strlen(cfg.api_base);
  while (alen > 0 && cfg.api_base[alen - 1] == '/')
    cfg.api_base[--alen] = 0;

  /* Headless defaults to auto-approve shell/write (no interactive confirm). */
  if (cfg.headless)
    cfg.auto_approve = 1;

  /* Default session under <workspace>/.agent/sessions/ (OpenCode-like). */
  if (!session_explicit) {
    char id[128];
    if (cst_agent_store_resolve_default(cfg.workspace_root, cfg.session_path,
                                        sizeof(cfg.session_path), id,
                                        sizeof(id)) != 0) {
      fprintf(stderr, "failed to init .agent/sessions under %s\n",
              cfg.workspace_root);
      curl_global_cleanup();
      return 1;
    }
    fprintf(stderr, "session %s\n", id);
  }

  if (do_demo) {
    int rc = demo_ctl_impl(cfg.workspace_root);
    curl_global_cleanup();
    return rc;
  }

  if (force_ask_key || !key_from_cli) {
    if (force_ask_key) {
      if (cst_creds_prompt_api_key(cfg.api_key, sizeof(cfg.api_key)) != 0) {
        fprintf(stderr, "API key prompt cancelled\n");
        curl_global_cleanup();
        return 1;
      }
      if (cst_creds_save_api_key(cfg.api_key) != 0)
        fprintf(stderr, "warning: failed to save credentials\n");
      else
        fprintf(stderr, "saved API key to ~/.config/cst-agent/credentials\n");
      /* --ask-key alone: save and exit unless running a turn/TUI */
      if (!cfg.headless && !prompt) {
        fprintf(stderr, "using %s model=%s\n", cfg.api_base, cfg.model);
        curl_global_cleanup();
        return 0;
      }
    } else if (!cfg.api_key[0]) {
      if (cst_creds_ensure_api_key(cfg.api_key, sizeof(cfg.api_key)) != 0) {
        fprintf(stderr, "no API key (set CST_API_KEY or use --ask-key)\n");
        curl_global_cleanup();
        return 1;
      }
    }
  } else if (key_from_cli) {
    /* persist CLI-provided key so next launch can reuse */
    if (cst_creds_save_api_key(cfg.api_key) != 0)
      fprintf(stderr, "warning: failed to save credentials\n");
  }

  fprintf(stderr, "using %s model=%s\n", cfg.api_base, cfg.model);

  cst_agent_t *agent = cst_agent_create(&cfg);
  if (!agent) {
    fprintf(stderr, "failed to create agent (session path?)\n");
    curl_global_cleanup();
    return 1;
  }

  int rc = 0;
  if (cfg.headless) {
    if (!prompt) {
      fprintf(stderr, "--headless requires --prompt\n");
      rc = 1;
    } else {
      char err[512];
      if (cst_agent_run_turn(agent, prompt, err, sizeof(err)) != 0) {
        fprintf(stderr, "turn failed: %s\n", err);
        rc = 1;
      } else {
        cst_session_t *s = cst_agent_session(agent);
        for (int i = 0; i < cst_session_count(s); i++) {
          const cst_message_t *m = cst_session_get(s, i);
          printf("[%d role=%d] %s\n", i, (int)m->role,
                 m->content ? m->content : "");
        }
      }
    }
  } else {
    rc = cst_tui_run(agent);
  }

  cst_agent_destroy(agent);
  curl_global_cleanup();
  return rc;
}