/*
 * Mr. 4th Dimention - Allen Webster
 *
 * 03.01.2017
 *
 * File layer for 4coder
 *
 */

// TOP

//
// Edit Position Basics
//

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};

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;
}

//
// Undo Basics
//

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;
};


//
// Highlighting Information
//

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


//
// Editing_File
//

struct Editing_File_Settings{
    i32 base_map_id;
    i32 display_width;
    i32 minimum_base_display_width;
    i32 wrap_indicator;
    b32 dos_write_mode;
    b32 virtual_white;
    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};

struct Editing_File_State{
    Buffer_Type buffer;
    
    i32 *wrap_line_index;
    i32 wrap_max;
    
    i32 *character_starts;
    i32 character_start_max;
    
    f32 *line_indents;
    i32 line_indent_max;
    
    i32 wrap_line_count;
    
    i32 *wrap_positions;
    i32 wrap_position_count;
    i32 wrap_position_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;
};
static Editing_File null_editing_file = {0};


//
// Manipulating a file's Edit_Pos array
//

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);
}


//
// 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);
}


//
// Dirty Flags
//

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);
}


// BOTTOM