#include "editor_gui_internal.h"

static U8 editor_contextmenu_item_enabled( const EDITOR_CONTEXTMENU_ITEM* item ) {
  if( !item )
    return 0;

  if( item->enabled_cb )
    return item->enabled_cb( item );

  return item->enabled;
}

static I32 editor_contextmenu_title_h( const GUI_EDITOR_CONTEXTMENU* menu ) {
  return ( menu && menu->title[0] ) ? 18 : 0;
}

static I32 editor_contextmenu_row_h() {
  return 20;
}

static I32 editor_contextmenu_width( LIST<EDITOR_CONTEXTMENU_ITEM>* items, const char* title ) {
  I32 width = EDITOR_TOOLBAR_DROPDOWN_W;
  if( title && title[0] ) {
    I32 text_w = 0;
    gui_draw_get_str_bounds( &text_w, 0, FNT_JPN12, "%s", title );
    width = max( width, text_w + 18 );
  }

  if( !items )
    return width;

  for( I32 i = 0; i < (I32)items->size; ++i ) {
    I32 text_w = 0;
    gui_draw_get_str_bounds( &text_w, 0, FNT_JPN12, "%s", ( *items )[i].text );
    width = max( width, text_w + 20 );
  }

  return width;
}

static I32 editor_contextmenu_height( LIST<EDITOR_CONTEXTMENU_ITEM>* items, const char* title ) {
  I32 height = 4 + editor_contextmenu_row_h() * ( items ? (I32)items->size : 0 );
  if( title && title[0] )
    height += 18 + 1;
  return max( height, editor_contextmenu_row_h() + 4 );
}

static I32 editor_contextmenu_items_y( GUI_EDITOR_CONTEXTMENU* menu ) {
  I32 y = gui_rely( menu ) + 2;
  if( menu->title[0] )
    y += editor_contextmenu_title_h( menu ) + 1;
  return y;
}

static I32 editor_contextmenu_hit_test( GUI_EDITOR_CONTEXTMENU* menu, I32 mx, I32 my ) {
  if( !menu || !menu->items )
    return -1;

  I32 x = gui_relx( menu );
  I32 y = gui_rely( menu );
  if( mx < x || mx >= x + menu->w || my < y || my >= y + menu->h )
    return -1;

  I32 items_y = editor_contextmenu_items_y( menu );
  if( my < items_y )
    return -1;

  I32 idx = ( my - items_y ) / editor_contextmenu_row_h();
  if( idx < 0 || idx >= (I32)menu->items->size )
    return -1;

  return idx;
}

static void gui_editor_contextmenu_draw_fn( void* ptr ) {
  GUI_EDITOR_CONTEXTMENU* menu = (GUI_EDITOR_CONTEXTMENU*)ptr;
  if( !menu || !menu->items || !menu->items->size )
    return;

  I32 x = gui_relx( menu );
  I32 y = gui_rely( menu );
  I32 mx = 0, my = 0;
  if( editor_menu_hover_mask_active ) {
    mx = editor_menu_hover_real_x;
    my = editor_menu_hover_real_y;
  } else {
    gui_cursor_pos( &mx, &my );
  }
  I32 hit = editor_contextmenu_hit_test( menu, mx, my );
  U8 m1 = gui_mbutton_down( GUI_MBTNLEFT );
  CLR hover_fill = CLR::blend( ui_clr.border, ui_clr.bg, 0.70f );
  CLR active_fill = CLR::blend( ui_clr.bg_sec, ui_clr.border, 0.22f );

  CLR border = gui_is_fg_window( menu ) ? ui_clr.border : ui_clr.border_inactive;
  gui_draw_frect( x, y, menu->w, menu->h, border );
  gui_draw_frect( x + 1, y + 1, max( 1, menu->w - 2 ), max( 1, menu->h - 2 ), ui_clr.bg_sec );

  I32 cy = y + 2;
  if( menu->title[0] ) {
    gui_draw_str( x + 8, cy + 1, ALIGN_L, FNT_JPN12, ui_clr.txt, "%s", menu->title );
    cy += editor_contextmenu_title_h( menu );
    gui_draw_line( x + 1, cy, x + menu->w - 2, cy, border );
    cy += 1;
  }

  for( I32 i = 0; i < (I32)menu->items->size; ++i ) {
    EDITOR_CONTEXTMENU_ITEM* item = &( *menu->items )[i];
    U8 enabled = editor_contextmenu_item_enabled( item );
    U8 hovered = hit == i;
    U8 active = menu->held && menu->held_idx == i && m1 && enabled;

    CLR fill = ui_clr.bg_sec;
    if( active )
      fill = active_fill;
    else if( hovered )
      fill = hover_fill;

    gui_draw_frect( x + 1, cy + i * editor_contextmenu_row_h(), max( 1, menu->w - 2 ), editor_contextmenu_row_h(), fill );
    gui_draw_str(
      x + 8,
      cy + i * editor_contextmenu_row_h() + 2,
      ALIGN_L,
      FNT_JPN12,
      enabled ? ui_clr.txt : ui_clr.txt_inactive,
      "%s",
      item->text
    );
  }
}

static void gui_editor_contextmenu_input_fn( void* ptr ) {
  GUI_EDITOR_CONTEXTMENU* menu = (GUI_EDITOR_CONTEXTMENU*)ptr;
  if( !menu || !menu->items || !menu->items->size )
    return;

  U8 m1 = gui_mbutton_down( GUI_MBTNLEFT );
  U8 m2 = gui_mbutton_down( GUI_MBTNRIGHT );
  if( menu->initheld ) {
    if( m1 || m2 )
      return;
    menu->initheld = 0;
    return;
  }

  I32 mx = 0, my = 0;
  gui_cursor_pos( &mx, &my );
  I32 hit = editor_contextmenu_hit_test( menu, mx, my );

  if( m1 || m2 ) {
    if( !menu->held ) {
      menu->held = 1;
      menu->held_idx = hit;
    }
    return;
  }

  if( !menu->held )
    return;

  if( hit == -1 ) {
    editor_hide_contextmenu();
    return;
  }

  if( hit == menu->held_idx ) {
    EDITOR_CONTEXTMENU_ITEM* item = &( *menu->items )[hit];
    if( editor_contextmenu_item_enabled( item ) && item->cb ) {
      item->cb( item->data );
      editor_hide_contextmenu();
      return;
    }
  }

  menu->held = 0;
  menu->held_idx = -1;
}

void editor_hide_contextmenu() {
  if( !editor || !editor->gui.contextmenu )
    return;

  GUI_EDITOR_CONTEXTMENU* menu = editor->gui.contextmenu;
  editor->gui.contextmenu = 0;

  if( menu->parent ) {
    I32 idx = menu->parent->children.idx_of( (GUI_BASE*)menu );
    if( idx != -1 )
      menu->parent->children.erase( idx );
  }

  GUI_EDITOR_TOOLBAR* bar = (GUI_EDITOR_TOOLBAR*)editor->gui.header_toolbar;
  if( bar )
    bar->active_root = -1;

  gui_free( menu );
}

U8 editor_contextmenu_open() {
  return editor && editor->gui.contextmenu && editor->gui.contextmenu->enabled;
}

void editor_show_contextmenu( I32 x, I32 y, LIST<EDITOR_CONTEXTMENU_ITEM>* items, const char* title ) {
  editor_hide_contextmenu();
  if( !editor || !editor->wnd || !items || !items->size )
    return;

  GUI_EDITOR_CONTEXTMENU* menu = new GUI_EDITOR_CONTEXTMENU;
  menu->items = items;
  menu->draw_fn = gui_editor_contextmenu_draw_fn;
  menu->input_fn = gui_editor_contextmenu_input_fn;
  menu->enabled = 1;
  menu->initheld = 1;
  menu->held = 0;
  menu->held_idx = -1;
  menu->parent = editor->wnd;
  snprintf( menu->name, sizeof( menu->name ), "EDITOR_CONTEXTMENU" );
  snprintf( menu->title, sizeof( menu->title ), "%s", title ? title : "" );

  menu->w = editor_contextmenu_width( items, title );
  menu->h = editor_contextmenu_height( items, title );
  menu->xbound = menu->w;
  menu->ybound = menu->h;

  if( x + menu->w > editor->wnd->w - 2 )
    x = max( 1, editor->wnd->w - menu->w - 2 );
  if( y + menu->h > editor->wnd->h - 2 )
    y = max( 1, editor->wnd->h - menu->h - 2 );
  if( x < 1 ) x = 1;
  if( y < 1 ) y = 1;

  menu->x = x;
  menu->y = y;
  editor->wnd->children.push( menu );
  editor->gui.contextmenu = menu;
}