module m_screen
implicit none

    integer::max_x, max_y
    integer::winid
    
    integer::cell_size
    integer::xoffset, yoffset
    integer::scorex, scorey

contains

    subroutine init()
    use bgi
    use m_constants
    implicit none
    
        winid = initwindow(SCREEN_W, SCREEN_H, "Fetris!")
        call setbkcolor(BLACK)
        
        cell_size = (SCREEN_H-20)/ROWS
        xoffset = 10
        yoffset = 10
        
        call setcolor(WHITE)
        call line(xoffset-2, yoffset-2, xoffset-2, yoffset + (SCREEN_H-20) + 2)
        call line(xoffset-2, yoffset + (SCREEN_H-20) + 2, &
                  xoffset + cell_size*COLUMNS + 2, yoffset + (SCREEN_H-20) + 2)
        call line(xoffset + cell_size*COLUMNS + 2, yoffset + (SCREEN_H-20) + 2, &
                  xoffset + cell_size*COLUMNS + 2, yoffset-2)
        
        scorex = xoffset + cell_size*COLUMNS + 40
        scorey = yoffset
        
        call settextstyle(9, HORIZ_DIR, 2)
        
    end subroutine init
    
    subroutine shutdown()
    use bgi
    implicit none
    
        call closegraph(winid)
        
    end subroutine shutdown
    
    subroutine draw_one_cell(r, c, v)
    use bgi
    use m_constants
    implicit none
        
    integer, intent(in)::r, c, v
    integer::x,y
    
        x = xoffset + (c - 1)*cell_size
        y = yoffset + (ROWS - r + 1)*cell_size
        
        if(v .EQ. 0) then
            call setfillstyle(SOLID_FILL, BLACK)
            call setcolor(BLACK)
        else
            call setfillstyle(SOLID_FILL, v)
            call setcolor(v)
        end if
        
        call bar(x, y, x+cell_size, y+cell_size)
        
    end subroutine draw_one_cell
    
    subroutine draw_board(g)
    use m_game
    use bgi
    implicit none
    
    type(game)::g
    integer::r, c
    
        do r = 1, ROWS
            do c = 1, COLUMNS
                call draw_one_cell(r, c, g%board(r, c))
            end do
        end do
    
    end subroutine draw_board
    
    subroutine draw_score(g)
    use m_game
    use bgi
    use iso_c_binding, only: C_NULL_CHAR
    implicit none
    
    type(game)::g
    
    character(120)::scoretext
    
        write(scoretext, *) "Score:", g%score
        
        call setcolor(BLACK)
        call setfillstyle(SOLID_FILL, BLACK)
        call bar(scorex, scorey, SCREEN_W, 40)
        call setcolor(WHITE)
        call outtextxy(scorex, scorey, trim(scoretext)//C_NULL_CHAR)
        
    end subroutine draw_score
    
    subroutine show_loss(score)
    use bgi
    use m_constants
    implicit none
        
        integer, intent(in)::score
        character(120)::scoretext
        integer::ignored
        
        call setfillstyle(SOLID_FILL, LIGHTRED)
        call bar(SCREEN_W/2 - 100, SCREEN_H/3, SCREEN_W/2 + 100, SCREEN_H/3+120)
        call setbkcolor(LIGHTRED)
        call setcolor(BLACK)
        
        write(scoretext, *) "Score:", score
        
        call outtextxy(SCREEN_W/2 - 80, SCREEN_H/3+20, " GAME OVER"//C_NULL_CHAR)
        call outtextxy(SCREEN_W/2 - 80, SCREEN_H/3+60, trim(scoretext)//C_NULL_CHAR)
        call outtextxy(SCREEN_W/2 - 80, SCREEN_H/3+80, " Press any key to exit"//C_NULL_CHAR)
        
        ignored = getch()
        
    end subroutine show_loss
    
end module m_screen