include ..\arwen\arwen.ew
include ..\arwen\axtra.ew

constant N = 5, -- columns
         M = 4, -- rows
         cLetter = Yellow,  -- initial colour(!)
         cChosen = Purple,
         cPlayr2 = Purple,  -- (2 player if!=c_Chosen)
         cHover  = White,
         cLines  = Black,
         cSelect = Black,   -- (text/list of selected letters)
         cBackgnd = #EFF8FA,
         letters = shuffle("ABCDEFGHIJKLMNOPQRSTUVWXYZ")[1..N*M]
sequence fonts  -- list of {width,handle}, see set_font()
string chosen = ""

constant main = create(Window, "honeycomb", 0, 0, 20, 20, 520, 540, 0),
         mainDC = getPrivateDC(main),
         viewDC = c_func(xCreateCompatibleDC, {NULL}),
         pSize = allocate_Point()

integer ls,         -- length of a single side
        dx, dy,     -- bounding rectangle of a sloping side
        ox, oy,     -- offsets needed to center things
        lw          -- line width (10% of ls, tweaked)

-- The total bounding rectange of a completed N by M honeycomb is N*(ls+dx)+dx by (2*M+1)*dy.
--  However, as space for the chosen letters, pretend there is an extra row at the bottom.
-- Use that to determine the best ls, and hence dx and dy, as the window is resized.

constant cos60 = cos(2*PI*60/360),      -- dx = ls*cos60 (cos60=0.5)
         sin60 = sin(2*PI*60/360)       -- dy = ls*sin60

function font_info(integer size)
atom hFont = createFontForDC(viewDC, "Calibri", size, Bold)
    {} = selectObject(viewDC,hFont)
    {} = c_func(xGetTextExtentPoint32,{viewDC,"W",1,pSize})
    return {peek4u(pSize),hFont}
end function
fonts = {font_info(1)}

procedure set_font(atom ls)
    while length(fonts)<=200    -- (arbitrary limit)
      and fonts[$][1]<ls do     -- until slightly too big
        fonts = append(fonts,font_info(length(fonts)+1))
    end while
    for i=length(fonts) to 1 by -1 do
        if fonts[i][1]<=ls then
            {} = selectObject(viewDC,fonts[i][2])
            exit
        end if
    end for
end procedure

integer mx=0, my=0  -- mouse hover cell

procedure drawHexagon(integer x, integer y)
integer k = (y-1)*N+x
integer ch = letters[k]
string s = letters[k..k]
sequence points
    -- calculate position of left mid:
    atom x0 = (x-1)*(ls+dx) + ox + 5
    atom y0 = (2*y-mod(x,2))*dy + oy + 10
    -- and 3 more x co-ords, and above/below y0:
    atom x1 = x0+dx, x2 = x1+ls, x3 = x2+dx,
         ya = y0-dy, yb = y0+dy
    -- points are {{left,top},top,right,btm,btm,home(left)}
    points = {{x0,y0,x1,ya},{x2,ya},{x3,y0},{x2,yb},{x1,yb},{x0,y0}}
    k = find(ch,chosen)
    setPenColor(iff(k?iff(mod(k,2)?cChosen:cPlayr2):iff(x=mx and y=my?cHover:cLetter)))
    drawPolygonh(viewDC,points)
    setPenColor(cLines)
    drawLinesh(viewDC,points)
    {} = c_func(xGetTextExtentPoint32,{viewDC,s,1,pSize})
    x0 += dx+ls/2-peek4u(pSize)/2 -- centre-width/2
    y0 -= peek4u(pSize+4)/2       -- (centre)-height/2
    wPuts2(viewDC,x0,y0,s)
end procedure

function xy_to_hex(sequence xy)
integer x, y, gx, gy, rx, ry, hx=0, hy=0

    if dx!=0 and dy!=0 then -- (avoid divide by 0)
        x = xy[1]-ox-5
        y = xy[2]-oy-10+2*dy

        -- Credit: Matt Lewis (hexes.exw)
        -- (but I basically tilted it on its head
        --  and tweaked it using trial and error;
        --  see commented out loop in WM_PAINT.)
        gx = floor(x/dx)
        gy = floor((y-dy)/dy)
        rx = remainder(x,dx)
        ry = remainder(y,dy)

        hx = floor(gx/3+0.7)
        if remainder(gx,3)<1 then
            atom mxb = (dx/dy)*ry
            -- need to check the slope
            if remainder(hx,2)!=remainder(gy,2) then
                mxb = dx-mxb
            end if
            hx += (rx>mxb)
        end if
        hy = floor((gy+remainder(hx,2))/2)
    end if
    return {hx,hy}
end function

integer dw = 0, dh = 0      -- client area width and height
atom bmView
integer vwX = 0, vwY = 0    -- actual size of the view bitmap

function mainHandler(integer id, integer msg, atom wParam, object lParam)
integer ch

    if msg=WM_SIZE then
        {{},{},dw,dh} = getClientRect(main)
        if dw>vwX or dh>vwY then
            -- we need a bigger bitmap
            bmView = c_func(xCreateCompatibleBitmap, {mainDC, dw, dh})
            {} = deleteObject(selectObject(viewDC,bmView))
            {vwX,vwY} = {dw,dh}
        end if
        --  width = N*(ls+dx)+dx = ls*(N*(1+cos60)+cos60),
        --  height = (2*M+3)*dy = ls*(2*M+3)*sin60, pick whichever fits:
        ls = min(floor((dw-10)/(N*(1+cos60)+cos60)),
                 floor((dh-20)/((2*M+3)*sin60)))
        dx = floor(ls*cos60)    -- (same as ls/2)
        dy = floor(ls*sin60)
        ox = floor((dw-((N*(ls+dx))+dx))/2)
        oy = floor((dh-((2*M+3)*dy))/2)
        lw = floor((ls-10)/10)+1
        setPenWidth(lw)
        set_font(ls)
    elsif msg=WM_PAINT then
        setPenColor(cBackgnd)
        drawRectangleh(viewDC, True, 0, 0, dw, dh)
        for x=1 to N do
            for y=1 to M do
                drawHexagon(x,y)
            end for
        end for
        -- text/list of selected letters goes where (M+2)th row would:
        setPenColor(cSelect)
        wPuts2(viewDC,ox+dx+5,oy+(2*M+1)*dy+10,chosen)
        -- I needed this to get xy_to_hex() working:
--      for i=1 to 400 do
--          for j=1 to 400 do
--              if xy_to_hex({i,j})={1,1} then
--                  drawRectangleh(viewDC, True, i, j, i+1, j+1)
--              end if
--          end for
--      end for
        void = c_func(xBitBlt,{mainDC,0,0,dw,dh,viewDC,0,0,SRCCOPY})
    elsif msg=WM_CHAR then
        if wParam=VK_ESCAPE then
            closeWindow(main)
            if id then end if -- suppress warnings
--      elsif wParam='!' then
--          ?9/0
        else
            ch = upper(wParam)
            if find(ch,letters) and not find(ch,chosen) then
                chosen &= ch
                repaintWindow(main)
            end if
        end if
    elsif msg=WM_MOUSEMOVE then
        {mx,my} = xy_to_hex(lParam)
        repaintWindow(main)
    elsif msg = WM_LBUTTONDOWN then
        {mx,my} = xy_to_hex(lParam)
        if mx>=1 and mx<=N
        and my>=1 and my<=M then
            ch = letters[(my-1)*N+mx]
            if find(ch,letters) and not find(ch,chosen) then
                chosen &= ch
                repaintWindow(main)
            end if
        end if
    elsif msg=WM_GETMINMAXINFO then
        -- below this, things stop working...
        poke4(lParam+MINMAXINFO_ptMinTrackSize,{188,250})
    end if
    return 0
end function
setHandler(main,routine_id("mainHandler"))

WinMain(main, SW_NORMAL)