4coder/4ed_file.cpp

/*
 * Mr. 4th Dimention - Allen Webster
 *
 * 20.02.2016
 *
 * File editing view for 4coder
 *
 */

// TOP

enum Edit_Pos_Set_Type{
    EditPos_None,
    EditPos_CursorSet,
    EditPos_ScrollSet
};
struct File_Edit_Positions{
    GUI_Scroll_Vars scroll;
    Full_Cursor cursor;
    i32 mark;
    f32 preferred_x;
    i32 scroll_i;
    i32 last_set_type;
    b32 in_view;
};
static File_Edit_Positions null_edit_pos = {0};

enum Edit_Type{
    ED_NORMAL,
    ED_REVERSE_NORMAL,
    ED_UNDO,
    ED_REDO,
};

struct Edit_Step{
    Edit_Type type;
    union{
        struct{
            b32 can_merge;
            Buffer_Edit edit;
            i32 next_block;
            i32 prev_block;
        };
        struct{
            i32 first_child;
            i32 inverse_first_child;
            i32 inverse_child_count;
            i32 special_type;
        };
    };
    i32 child_count;
};

struct Edit_Stack{
    u8 *strings;
    i32 size, max;
    
    Edit_Step *edits;
    i32 edit_count, edit_max;
};

struct Small_Edit_Stack{
    u8 *strings;
    i32 size, max;
    
    Buffer_Edit *edits;
    i32 edit_count, edit_max;
};

struct Undo_Data{
    Edit_Stack undo;
    Edit_Stack redo;
    Edit_Stack history;
    Small_Edit_Stack children;
    
    i32 history_block_count, history_head_block;
    i32 edit_history_cursor;
    b32 current_block_normal;
};

struct Text_Effect{
    i32 start, end;
    u32 color;
    f32 seconds_down, seconds_max;
};

// NOTE(allen): The Editing_File struct is now divided into two
// parts.  Variables in the Settings part can be set even when the
// file is still streaming in, and persists thorugh all operations except
// for the initial allocation of the file.
struct Editing_File_Settings{
    i32 base_map_id;
    i32 display_width;
    i32 dos_write_mode;
    i16 font_id;
    b8 unwrapped_lines;
    b8 tokens_exist;
    b8 is_initialized;
    b8 unimportant;
    b8 read_only;
    b8 never_kill;
};
static Editing_File_Settings null_editing_file_settings = {0};

// NOTE(allen): This part of the Editing_File is cleared whenever
// the contents of the file is set.
struct Editing_File_State{
    Buffer_Type buffer;
    
    f32 *wraps;
    i32 wrap_max;
    
    i32 *character_starts;
    i32 character_start_max;
    
    f32 *line_indents;
    i32 line_indent_max;
    
    Undo_Data undo;
    
    Cpp_Token_Array token_array;
    Cpp_Token_Array swap_array;
    u32 lex_job;
    b32 tokens_complete;
    b32 still_lexing;
    
    Text_Effect paste_effect;
    
    Dirty_State dirty;
    u32 ignore_behind_os;
    
    File_Edit_Positions edit_pos_space[16];
    File_Edit_Positions *edit_poss[16];
    i32 edit_poss_count;
};
static Editing_File_State null_editing_file_state = {0};

struct Editing_File_Name{
    char live_name_[256];
    char source_path_[256];
    char extension_[16];
    String live_name;
    String source_path;
    String extension;
};

struct Editing_File_Canon_Name{
    char name_[256];
    String name;
};

struct File_Node{
    File_Node *next, *prev;
};

union Buffer_Slot_ID{
    i32 id;
    i16 part[2];
};

inline Buffer_Slot_ID
to_file_id(i32 id){
    Buffer_Slot_ID result;
    result.id = id;
    return(result);
}

struct Editing_File{
    // NOTE(allen): node must be the first member of Editing_File!
    File_Node node;
    Editing_File_Settings settings;
    struct{
        b32 is_loading;
        b32 is_dummy;
        Editing_File_State state;
    };
    Editing_File_Name name;
    Editing_File_Canon_Name canon;
    Buffer_Slot_ID id;
    u64 unique_buffer_id;
};

struct Non_File_Table_Entry{
    String name;
    Buffer_Slot_ID id;
};

struct File_Array{
    Editing_File *files;
    i32 size;
};

struct Working_Set{
    File_Array *file_arrays;
    i32 file_count, file_max;
    i16 array_count, array_max;
    
	File_Node free_sentinel;
    File_Node used_sentinel;
    
    Table canon_table;
    Table name_table;
    
	String clipboards[64];
	i32 clipboard_size, clipboard_max_size;
	i32 clipboard_current, clipboard_rolling;
    
    u64 unique_file_counter;
    
    File_Node *sync_check_iter;
    
    i32 default_display_width;
};

//
// File_Edit_Positions stuff
//

internal void
edit_pos_set_cursor_(File_Edit_Positions *edit_pos,
                     Full_Cursor cursor,
                     b32 set_preferred_x,
                     b32 unwrapped_lines){
    edit_pos->cursor = cursor;
    if (set_preferred_x){
        edit_pos->preferred_x = cursor.wrapped_x;
        if (unwrapped_lines){
            edit_pos->preferred_x = cursor.unwrapped_x;
        }
    }
    edit_pos->last_set_type = EditPos_CursorSet;
}

internal void
edit_pos_set_scroll_(File_Edit_Positions *edit_pos, GUI_Scroll_Vars scroll){
    edit_pos->scroll = scroll;
    edit_pos->last_set_type = EditPos_ScrollSet;
}

internal i32
edit_pos_get_index(Editing_File *file, File_Edit_Positions *edit_pos){
    i32 edit_pos_index = -1;
    
    i32 count = file->state.edit_poss_count;
    File_Edit_Positions **edit_poss = file->state.edit_poss;
    for (i32 i = 0; i < count; ++i){
        if (edit_poss[i] == edit_pos){
            edit_pos_index = i;
            break;
        }
    }
    
    return(edit_pos_index);
}

internal b32
edit_pos_move_to_front(Editing_File *file, File_Edit_Positions *edit_pos){
    b32 result = false;
    
    if (file && edit_pos){
        i32 edit_pos_index = edit_pos_get_index(file, edit_pos);
        Assert(edit_pos_index != -1);
        
        File_Edit_Positions **edit_poss = file->state.edit_poss;
        
        memmove(edit_poss + 1, edit_poss, edit_pos_index*sizeof(*edit_poss));
        
        edit_poss[0] = edit_pos;
        result = true;
    }
    
    return(result);
}

internal b32
edit_pos_unset(Editing_File *file, File_Edit_Positions *edit_pos){
    b32 result = false;
    
    if (file && edit_pos){
        i32 edit_pos_index = edit_pos_get_index(file, edit_pos);
        Assert(edit_pos_index != -1);
        
        i32 count = file->state.edit_poss_count;
        File_Edit_Positions **edit_poss = file->state.edit_poss;
        
        memmove(edit_poss + edit_pos_index,
                edit_poss + edit_pos_index + 1,
                (count - edit_pos_index - 1)*sizeof(*edit_poss));
        
        edit_pos->in_view = false;
        
        if (file->state.edit_poss_count > 1){
            file->state.edit_poss_count -= 1;
        }
        result = true;
    }
    
    return(result);
}

internal File_Edit_Positions*
edit_pos_get_new(Editing_File *file, i32 index){
    File_Edit_Positions *result = 0;
    
    if (file && 0 <= index && index < 16){
        result = file->state.edit_pos_space + index;
        i32 edit_pos_index = edit_pos_get_index(file, result);
        
        if (edit_pos_index == -1){
            File_Edit_Positions **edit_poss = file->state.edit_poss;
            i32 count = file->state.edit_poss_count;
            
            if (count > 0){
                if (edit_poss[0]->in_view){
                    memcpy(result, edit_poss[0], sizeof(*result));
                    memmove(edit_poss+1, edit_poss, sizeof(*edit_poss)*count);
                    file->state.edit_poss_count = count + 1;
                }
                else{
                    Assert(count == 1);
                    memcpy(result, edit_poss[0], sizeof(*result));
                }
            }
            else{
                memset(result, 0, sizeof(*result));
                file->state.edit_poss_count = 1;
            }
            
            edit_poss[0] = result;
        }
        
        result->in_view = true;
    }
    
    return(result);
}

//
// File Cursor Seeking
//

inline Partial_Cursor
file_compute_cursor_from_pos(Editing_File *file, i32 pos){
    Partial_Cursor result = buffer_partial_from_pos(&file->state.buffer, pos);
    return(result);
}

inline Partial_Cursor
file_compute_cursor_from_line_character(Editing_File *file, i32 line, i32 character){
    Partial_Cursor result = buffer_partial_from_line_character(&file->state.buffer, line, character);
    return(result);
}

inline b32
file_compute_partial_cursor(Editing_File *file, Buffer_Seek seek, Partial_Cursor *cursor){
    b32 result = 1;
    switch (seek.type){
        case buffer_seek_pos:
        {
            *cursor = file_compute_cursor_from_pos(file, seek.pos);
        }break;
        
        case buffer_seek_line_char:
        {
            *cursor = file_compute_cursor_from_line_character(file, seek.line, seek.character);
        }break;
        
        default:
        {
            result = 0;
        }break;
    }
    return(result);
}

//
// Working_Set stuff
//

struct File_Name_Entry{
    String name;
    Buffer_Slot_ID id;
};

internal i32
tbl_name_compare(void *a, void *b, void *arg){
    String *fa = (String*)a;
    File_Name_Entry *fb = (File_Name_Entry*)b;
    
    i32 result = 1;
    if (match_ss(*fa, fb->name)){
        result = 0;
    }
    
    return(result);
}

internal void
working_set_extend_memory(Working_Set *working_set, Editing_File *new_space, i16 number_of_files){
    Buffer_Slot_ID id;
    i16 i, high_part;
    Editing_File *file_ptr;
    File_Node *free_sentinel;
    
    Assert(working_set->array_count < working_set->array_max);
    
    high_part = working_set->array_count++;
    working_set->file_arrays[high_part].files = new_space;
    working_set->file_arrays[high_part].size = number_of_files;
    
    working_set->file_max += number_of_files;
    
    id.part[1] = high_part;
    
    file_ptr = new_space;
    free_sentinel = &working_set->free_sentinel;
    for (i = 0; i < number_of_files; ++i, ++file_ptr){
        id.part[0] = i;
        file_ptr->id = id;
        dll_insert(free_sentinel, &file_ptr->node);
    }
}

inline Editing_File
editing_file_zero(){
    Editing_File file = {0};
    return(file);
}

internal Editing_File*
working_set_alloc(Working_Set *working_set){
    Editing_File *result = 0;
    File_Node *node;
    Buffer_Slot_ID id;
    
    if (working_set->file_count < working_set->file_max){
        node = working_set->free_sentinel.next;
        Assert(node != &working_set->free_sentinel);
        result = (Editing_File*)node;
        
        dll_remove(node);
        id = result->id;
        *result = editing_file_zero();
        result->id = id;
        result->unique_buffer_id = ++working_set->unique_file_counter;
        dll_insert(&working_set->used_sentinel, node);
        result->settings.display_width = working_set->default_display_width;
        ++working_set->file_count;
    }
    
    return(result);
}

internal Editing_File*
working_set_alloc_always(Working_Set *working_set, General_Memory *general){
    Editing_File *result = 0;
    Editing_File *new_chunk;
    i32 full_new_count = working_set->file_max;
    i16 new_count;
    
    if (full_new_count > max_i16) new_count = max_i16;
    else new_count = (i16)full_new_count;
    
    if (working_set->file_count == working_set->file_max &&
            working_set->array_count < working_set->array_max){
        new_chunk = gen_array(general, Editing_File, new_count);
        working_set_extend_memory(working_set, new_chunk, new_count);
    }
    result = working_set_alloc(working_set);
    
    return(result);
}

inline void
working_set_free_file(Working_Set  *working_set, Editing_File *file){
    if (working_set->sync_check_iter == &file->node){
        working_set->sync_check_iter = working_set->sync_check_iter->next;
    }
    
    file->is_dummy = 1;
    dll_remove(&file->node);
    dll_insert(&working_set->free_sentinel, &file->node);
    --working_set->file_count;
}

inline Editing_File*
working_set_index(Working_Set *working_set, Buffer_Slot_ID id){
    Editing_File *result = 0;
    File_Array *array = 0;
    
    if (id.part[1] >= 0 && id.part[1] < working_set->array_count){
        array = working_set->file_arrays + id.part[1];
        if (id.part[0] >= 0 && id.part[0] < array->size){
            result = array->files + id.part[0];
        }
    }
    
    return(result);
}

inline Editing_File*
working_set_index(Working_Set *working_set, i32 id){
    Editing_File *result = working_set_index(working_set, to_file_id(id));
    return(result);
}

inline Editing_File*
working_set_get_active_file(Working_Set *working_set, Buffer_Slot_ID id){
    Editing_File *result = 0;
    result = working_set_index(working_set, id);
    if (result && result->is_dummy){
        result = 0;
    }
    return(result);
}

inline Editing_File*
working_set_get_active_file(Working_Set *working_set, i32 id){
    Editing_File *result;
    result = working_set_get_active_file(working_set, to_file_id(id));
    return(result);
}

internal void
working_set_init(Working_Set *working_set, Partition *partition, General_Memory *general){
    i16 init_count = 16;
    i16 array_init_count = 256;
    
    dll_init_sentinel(&working_set->free_sentinel);
    dll_init_sentinel(&working_set->used_sentinel);
    
    working_set->array_max = array_init_count;
    working_set->file_arrays = push_array(partition, File_Array, array_init_count);
    
    Editing_File *files = push_array(partition, Editing_File, init_count);
    working_set_extend_memory(working_set, files, init_count);
    
    // NOTE(allen): init null file
    {
        Editing_File *null_file = working_set_index(working_set, 0);
        dll_remove(&null_file->node);
        null_file->is_dummy = 1;
        ++working_set->file_count;
    }
    
    // NOTE(allen): init canon table
    {
        i32 item_size = sizeof(File_Name_Entry);
        i32 table_size = working_set->file_max;
        i32 mem_size = table_required_mem_size(table_size, item_size);
        void *mem = general_memory_allocate(general, mem_size);
        memset(mem, 0, mem_size);
        table_init_memory(&working_set->canon_table, mem, table_size, item_size);
    }
    
    // NOTE(allen): init name table
    {
        i32 item_size = sizeof(File_Name_Entry);
        i32 table_size = working_set->file_max;
        i32 mem_size = table_required_mem_size(table_size, item_size);
        void *mem = general_memory_allocate(general, mem_size);
        memset(mem, 0, mem_size);
        table_init_memory(&working_set->name_table, mem, table_size, item_size);
    }
}

inline void
working_set__grow_if_needed(Table *table, General_Memory *general, void *arg, Hash_Function *hash_func, Compare_Function *comp_func){
    if (table_at_capacity(table)){
        Table btable = {0};
        i32 new_max = table->max * 2;
        i32 mem_size = table_required_mem_size(new_max, table->item_size);
        void *mem = general_memory_allocate(general, mem_size);
        table_init_memory(&btable, mem, new_max, table->item_size);
        table_clear(&btable);
        table_rehash(table, &btable, 0, hash_func, comp_func);
        general_memory_free(general, table->hash_array);
        *table = btable;
    }
}

internal Editing_File*
working_set_contains_basic(Working_Set *working_set, Table *table, String name){
    Editing_File *result = 0;
    
    File_Name_Entry *entry = (File_Name_Entry*)
        table_find_item(table, &name, 0, tbl_string_hash, tbl_string_compare);
    if (entry){
        result = working_set_index(working_set, entry->id);
    }
    
    return(result);
}

internal b32
working_set_add_basic(General_Memory *general, Working_Set *working_set, Table *table,
                      Editing_File *file, String name){
    working_set__grow_if_needed(table, general,
                                0, tbl_string_hash, tbl_string_compare);
    
    File_Name_Entry entry;
    entry.name = name;
    entry.id = file->id;
    b32 result = (table_add(table, &entry, 0, tbl_string_hash, tbl_string_compare) == 0);
    return(result);
}

internal void
working_set_remove_basic(Working_Set *working_set, Table *table, String name){
    table_remove_match(table, &name, 0, tbl_string_hash, tbl_string_compare);
}

internal Editing_File*
working_set_canon_contains(Working_Set *working_set, String name){
    Editing_File *result =
        working_set_contains_basic(working_set, &working_set->canon_table, name);
    return(result);
}

internal b32
working_set_canon_add(General_Memory *general, Working_Set *working_set,
                     Editing_File *file, String name){
    b32 result = working_set_add_basic(general, working_set, &working_set->canon_table, file, name);
    return(result);
}

internal void
working_set_canon_remove(Working_Set *working_set, String name){
    working_set_remove_basic(working_set, &working_set->canon_table, name);
}

internal Editing_File*
working_set_name_contains(Working_Set *working_set, String name){
    Editing_File *result =
        working_set_contains_basic(working_set, &working_set->name_table, name);
    return(result);
}

internal b32
working_set_name_add(General_Memory *general, Working_Set *working_set,
                     Editing_File *file, String name){
    b32 result = working_set_add_basic(general, working_set, &working_set->name_table, file, name);
    return(result);
}

internal void
working_set_name_remove(Working_Set *working_set, String name){
    working_set_remove_basic(working_set, &working_set->name_table, name);
}


// TODO(allen): Pick better first options.
internal Editing_File*
working_set_lookup_file(Working_Set *working_set, String string){
    Editing_File *file = 0;
    
    {
        // TODO(allen): use the name table for this
        File_Node *node, *used_nodes;
        used_nodes = &working_set->used_sentinel;
        for (dll_items(node, used_nodes)){
            file = (Editing_File*)node;
            if (string.size == 0 || match_ss(string, file->name.live_name)){
                break;
            }
        }
        if (node == used_nodes) file = 0;
    }
	
	if (!file){
        File_Node *node, *used_nodes;
        used_nodes = &working_set->used_sentinel;
        for (dll_items(node, used_nodes)){
            file = (Editing_File*)node;
            if (string.size == 0 || has_substr_s(file->name.live_name, string)){
                break;
            }
        }
        if (node == used_nodes) file = 0;
	}
    
	return (file);
}

internal void
touch_file(Working_Set *working_set, Editing_File *file){
    if (file){
        Assert(!file->is_dummy);
        dll_remove(&file->node);
        dll_insert(&working_set->used_sentinel, &file->node);
    }
}

// Hot Directory

struct Hot_Directory{
	String string;
	File_List file_list;
    // TODO(allen): eliminate slash
    char slash;
};

internal void
hot_directory_clean_end(Hot_Directory *hot_directory){
    String *str = &hot_directory->string;
    if (str->size != 0 && str->str[str->size-1] != hot_directory->slash){
        str->size = reverse_seek_slash(*str) + 1;
        str->str[str->size] = 0;
    }
}

internal i32
hot_directory_quick_partition(File_Info *infos, i32 start, i32 pivot){
    File_Info *p = infos + pivot;
    File_Info *a = infos + start;
    for (i32 i = start; i < pivot; ++i, ++a){
        i32 comp = 0;
        comp = p->folder - a->folder;
        if (comp == 0){
            comp = compare_cc(a->filename, p->filename);
        }
        if (comp < 0){
            Swap(File_Info, *a, infos[start]);
            ++start;
        }
    }
    Swap(File_Info, *p, infos[start]);
    return start;
}

internal void
hot_directory_quick_sort(File_Info *infos, i32 start, i32 pivot){
    i32 mid = hot_directory_quick_partition(infos, start, pivot);
    if (start < mid-1) hot_directory_quick_sort(infos, start, mid-1);
    if (mid+1 < pivot) hot_directory_quick_sort(infos, mid+1, pivot);
}

inline void
hot_directory_fixup(Hot_Directory *hot_directory, Working_Set *working_set){
    File_List *files = &hot_directory->file_list;
    if (files->count >= 2)
        hot_directory_quick_sort(files->infos, 0, files->count - 1);
}

inline void
hot_directory_set(System_Functions *system, Hot_Directory *hot_directory,
                  String str, Working_Set *working_set){
    b32 success = copy_checked_ss(&hot_directory->string, str);
    terminate_with_null(&hot_directory->string);
    if (success){
        if (str.size > 0){
            system->set_file_list(&hot_directory->file_list, str);
        }
        else{
            system->set_file_list(&hot_directory->file_list, make_string((char*)1, 0));
        }
    }
    hot_directory_fixup(hot_directory, working_set);
}

inline void
hot_directory_reload(System_Functions *system, Hot_Directory *hot_directory, Working_Set *working_set){
    system->set_file_list(&hot_directory->file_list, hot_directory->string);
    hot_directory_fixup(hot_directory, working_set);
}

internal void
hot_directory_init(Hot_Directory *hot_directory, String base, String dir, char slash){
	hot_directory->string = base;
    hot_directory->string.str[255] = 0;
    hot_directory->string.size = 0;
    copy_ss(&hot_directory->string, dir);
	append_s_char(&hot_directory->string, slash);
    hot_directory->slash = slash;
}

struct Hot_Directory_Match{
	String filename;
	b32 is_folder;
};

internal b32
filename_match(String query, Absolutes *absolutes, String filename){
    b32 result;
    result = (query.size == 0);
    if (!result) result = wildcard_match_s(absolutes, filename, 0);
    return result;
}

inline b32
buffer_needs_save(Editing_File *file){
    b32 result = 0;
    if (!file->settings.unimportant){
        if (file->state.dirty == DirtyState_UnsavedChanges){
            result = 1;
        }
    }
    return(result);
}

inline b32
buffer_can_save(Editing_File *file){
    b32 result = 0;
    if (!file->settings.unimportant){
        if (file->state.dirty == DirtyState_UnsavedChanges ||
            file->state.dirty == DirtyState_UnloadedChanges){
            result = 1;
        }
    }
    return(result);
}

inline b32
file_is_ready(Editing_File *file){
    b32 result = 0;
    if (file && file->is_loading == 0){
        result = 1;
    }
    return(result);
}

inline void
file_set_to_loading(Editing_File *file){
    file->state = null_editing_file_state;
    file->settings = null_editing_file_settings;
    file->is_loading = 1;
}

inline void
file_mark_clean(Editing_File *file){
    if (file->state.dirty != DirtyState_UnloadedChanges){
        file->state.dirty = DirtyState_UpToDate;
    }
}

inline void
file_mark_dirty(Editing_File *file){
    if (file->state.dirty != DirtyState_UnloadedChanges){
        file->state.dirty = DirtyState_UnsavedChanges;
    }
}

inline void
file_mark_behind_os(Editing_File *file){
    file->state.dirty = DirtyState_UnloadedChanges;
}

inline Dirty_State
file_get_sync(Editing_File *file){
    return (file->state.dirty);
}

internal void
editing_file_name_init(Editing_File_Name *name){
    name->live_name = make_fixed_width_string(name->live_name_);
    name->source_path = make_fixed_width_string(name->source_path_);
    name->extension = make_fixed_width_string(name->extension_);
}

internal b32
get_canon_name(System_Functions *system, Editing_File_Canon_Name *canon_name, String filename){
    canon_name->name = make_fixed_width_string(canon_name->name_);
    
    canon_name->name.size =
        system->get_canonical(filename.str, filename.size,
                              canon_name->name.str, canon_name->name.memory_size);
    terminate_with_null(&canon_name->name);
    
    b32 result = (canon_name->name.size != 0);
    return(result);
}

internal void
buffer_get_new_name(Working_Set *working_set, Editing_File_Name *name, String filename){
    Assert(name->live_name.str != 0);
    
    copy_checked_ss(&name->source_path, filename);
    copy_ss(&name->live_name, front_of_directory(filename));
    
    if (name->source_path.size == name->live_name.size){
        name->extension.size = 0;
    }
    else{
        String ext = file_extension(filename);
        copy_ss(&name->extension, ext);
    }
    
    {
        i32 original_len = name->live_name.size;
        i32 file_x = 0;
        b32 hit_conflict = 1;
        while (hit_conflict){
            hit_conflict = 0;
            
            File_Node *used_nodes = &working_set->used_sentinel, *node;
            for (dll_items(node, used_nodes)){
                Editing_File *file_ptr = (Editing_File*)node;
                if (file_is_ready(file_ptr)){
                    if (match_ss(name->live_name, file_ptr->name.live_name)){
                        ++file_x;
                        hit_conflict = 1;
                        break;
                    }
                }
            }
            
            if (hit_conflict){
                name->live_name.size = original_len;
                append_ss(&name->live_name, make_lit_string(" <"));
                append_int_to_str(&name->live_name, file_x);
                append_s_char(&name->live_name, '>');
            }
        }
    }
}

inline void
buffer_get_new_name(Working_Set *working_set, Editing_File_Name *name, char *filename){
    String f = make_string_slowly(filename);
    buffer_get_new_name(working_set, name, f);
}

internal void
buffer_bind_file(System_Functions *system, General_Memory *general, Working_Set *working_set,
                 Editing_File *file, String canon_filename){
    Assert(file->name.live_name.size == 0 &&
           file->name.source_path.size == 0 &&
           file->name.extension.size == 0);
    Assert(file->canon.name.size == 0);
    
    file->canon.name = make_fixed_width_string(file->canon.name_);
    copy_ss(&file->canon.name, canon_filename);
    terminate_with_null(&file->canon.name);
    system->add_listener(file->canon.name_);
    b32 result = working_set_canon_add(general, working_set, file, file->canon.name);
    Assert(result); AllowLocal(result);
}

internal void
buffer_unbind_file(System_Functions *system, Working_Set *working_set, Editing_File *file){
    Assert(file->name.live_name.size == 0 &&
           file->name.source_path.size == 0 &&
           file->name.extension.size == 0);
    Assert(file->canon.name.size != 0);
    
    system->remove_listener(file->canon.name_);
    working_set_canon_remove(working_set, file->canon.name);
    file->canon.name.size = 0;
}

internal void
buffer_bind_name(General_Memory *general, Working_Set *working_set,
                 Editing_File *file, String filename){
    Assert(file->name.live_name.size == 0 &&
           file->name.source_path.size == 0 &&
           file->name.extension.size == 0);
    
    Editing_File_Name new_name;
    editing_file_name_init(&new_name);
    buffer_get_new_name(working_set, &new_name, filename);
    
    editing_file_name_init(&file->name);
    copy_ss(&file->name.live_name, new_name.live_name);
    copy_ss(&file->name.source_path, new_name.source_path);
    copy_ss(&file->name.extension, new_name.extension);
    
    b32 result = working_set_name_add(general, working_set, file, file->name.live_name);
    Assert(result); AllowLocal(result);
}

internal void
buffer_unbind_name(Working_Set *working_set, Editing_File *file){
    Assert(file->name.live_name.size != 0);
    working_set_name_remove(working_set, file->name.live_name);
    file->name.live_name.size = 0;
    file->name.source_path.size = 0;
    file->name.extension.size = 0;
}

// BOTTOM