/// Nvim's own UI client, which attaches to a child or remote Nvim server.

#include <stdbool.h>
#include <stdint.h>
#include <stdlib.h>

#include "nvim/api/keysets_defs.h"
#include "nvim/api/private/dispatch.h"
#include "nvim/api/private/helpers.h"
#include "nvim/channel.h"
#include "nvim/eval.h"
#include "nvim/eval/typval_defs.h"
#include "nvim/event/loop.h"
#include "nvim/func_attr.h"
#include "nvim/globals.h"
#include "nvim/highlight.h"
#include "nvim/log.h"
#include "nvim/main.h"
#include "nvim/memory.h"
#include "nvim/msgpack_rpc/channel.h"
#include "nvim/os/os_defs.h"
#include "nvim/tui/tui.h"
#include "nvim/ui.h"
#include "nvim/ui_client.h"

#ifdef MSWIN
# include "nvim/os/os_win_console.h"
#endif

static TUIData *tui = NULL;
static bool ui_client_is_remote = false;

// uncrustify:off
#ifdef INCLUDE_GENERATED_DECLARATIONS
# include "ui_client.c.generated.h"
# include "ui_events_client.generated.h"
#endif
// uncrustify:on

uint64_t ui_client_start_server(int argc, char **argv)
{
  varnumber_T exit_status;
  char **args = xmalloc(((size_t)(2 + argc)) * sizeof(char *));
  int args_idx = 0;
  args[args_idx++] = xstrdup(argv[0]);
  args[args_idx++] = xstrdup("--embed");
  for (int i = 1; i < argc; i++) {
    args[args_idx++] = xstrdup(argv[i]);
  }
  args[args_idx++] = NULL;

  CallbackReader on_err = CALLBACK_READER_INIT;
  on_err.fwd_err = true;

  Channel *channel = channel_job_start(args, get_vim_var_str(VV_PROGPATH),
                                       CALLBACK_READER_INIT, on_err, CALLBACK_NONE,
                                       false, true, true, false, kChannelStdinPipe,
                                       NULL, 0, 0, NULL, &exit_status);

  // If stdin is not a pty, it is forwarded to the client.
  // Replace stdin in the TUI process with the tty fd.
  if (ui_client_forward_stdin) {
    close(0);
#ifdef MSWIN
    os_open_conin_fd();
#else
    dup(stderr_isatty ? STDERR_FILENO : STDOUT_FILENO);
#endif
  }

  return channel->id;
}

void ui_client_attach(int width, int height, char *term)
{
  MAXSIZE_TEMP_ARRAY(args, 3);
  ADD_C(args, INTEGER_OBJ(width));
  ADD_C(args, INTEGER_OBJ(height));

  MAXSIZE_TEMP_DICT(opts, 9);
  PUT_C(opts, "rgb", BOOLEAN_OBJ(true));
  PUT_C(opts, "ext_linegrid", BOOLEAN_OBJ(true));
  PUT_C(opts, "ext_termcolors", BOOLEAN_OBJ(true));
  if (term) {
    PUT_C(opts, "term_name", CSTR_AS_OBJ(term));
  }

  PUT_C(opts, "term_colors", INTEGER_OBJ(t_colors));
  if (!ui_client_is_remote) {
    PUT_C(opts, "stdin_tty", BOOLEAN_OBJ(stdin_isatty));
    PUT_C(opts, "stdout_tty", BOOLEAN_OBJ(stdout_isatty));
    if (ui_client_forward_stdin) {
      PUT_C(opts, "stdin_fd", INTEGER_OBJ(UI_CLIENT_STDIN_FD));
      ui_client_forward_stdin = false;  // stdin shouldn't be forwarded again #22292
    }
  }
  ADD_C(args, DICTIONARY_OBJ(opts));

  rpc_send_event(ui_client_channel_id, "nvim_ui_attach", args);
  ui_client_attached = true;
}

void ui_client_detach(void)
{
  rpc_send_event(ui_client_channel_id, "nvim_ui_detach", (Array)ARRAY_DICT_INIT);
  ui_client_attached = false;
}

void ui_client_run(bool remote_ui)
  FUNC_ATTR_NORETURN
{
  ui_client_is_remote = remote_ui;
  int width, height;
  char *term;
  tui_start(&tui, &width, &height, &term);

  ui_client_attach(width, height, term);

  // os_exit() will be invoked when the client channel detaches
  while (true) {
    LOOP_PROCESS_EVENTS(&main_loop, resize_events, -1);
  }
}

void ui_client_stop(void)
{
  if (!tui_is_stopped(tui)) {
    tui_stop(tui);
  }
}

void ui_client_set_size(int width, int height)
{
  // The currently known size will be sent when attaching
  if (ui_client_attached) {
    MAXSIZE_TEMP_ARRAY(args, 2);
    ADD_C(args, INTEGER_OBJ((int)width));
    ADD_C(args, INTEGER_OBJ((int)height));
    rpc_send_event(ui_client_channel_id, "nvim_ui_try_resize", args);
  }
}

UIClientHandler ui_client_get_redraw_handler(const char *name, size_t name_len, Error *error)
{
  int hash = ui_client_handler_hash(name, name_len);
  if (hash < 0) {
    return (UIClientHandler){ NULL, NULL };
  }
  return event_handlers[hash];
}

/// Placeholder for _sync_ requests with 'redraw' method name
///
/// async 'redraw' events, which are expected when nvim acts as a ui client.
/// get handled in msgpack_rpc/unpacker.c and directly dispatched to handlers
/// of specific ui events, like ui_client_event_grid_resize and so on.
Object handle_ui_client_redraw(uint64_t channel_id, Array args, Arena *arena, Error *error)
{
  api_set_error(error, kErrorTypeValidation, "'redraw' cannot be sent as a request");
  return NIL;
}

static HlAttrs ui_client_dict2hlattrs(Dictionary d, bool rgb)
{
  Error err = ERROR_INIT;
  Dict(highlight) dict = { 0 };
  if (!api_dict_to_keydict(&dict, KeyDict_highlight_get_field, d, &err)) {
    // TODO(bfredl): log "err"
    return HLATTRS_INIT;
  }
  return dict2hlattrs(&dict, rgb, NULL, &err);
}

void ui_client_event_grid_resize(Array args)
{
  if (args.size < 3
      || args.items[0].type != kObjectTypeInteger
      || args.items[1].type != kObjectTypeInteger
      || args.items[2].type != kObjectTypeInteger) {
    ELOG("Error handling ui event 'grid_resize'");
    return;
  }

  Integer grid = args.items[0].data.integer;
  Integer width = args.items[1].data.integer;
  Integer height = args.items[2].data.integer;
  tui_grid_resize(tui, grid, width, height);

  if (grid_line_buf_size < (size_t)width) {
    xfree(grid_line_buf_char);
    xfree(grid_line_buf_attr);
    grid_line_buf_size = (size_t)width;
    grid_line_buf_char = xmalloc(grid_line_buf_size * sizeof(schar_T));
    grid_line_buf_attr = xmalloc(grid_line_buf_size * sizeof(sattr_T));
  }
}

void ui_client_event_grid_line(Array args)
  FUNC_ATTR_NORETURN
{
  abort();  // unreachable
}

void ui_client_event_raw_line(GridLineEvent *g)
{
  int grid = g->args[0], row = g->args[1], startcol = g->args[2];
  Integer endcol = startcol + g->coloff;
  Integer clearcol = endcol + g->clear_width;
  LineFlags lineflags = g->wrap ? kLineFlagWrap : 0;

  tui_raw_line(tui, grid, row, startcol, endcol, clearcol, g->cur_attr, lineflags,
               (const schar_T *)grid_line_buf_char, grid_line_buf_attr);
}