load "iupe-dbuffer.lua"

dalosp.framebuffer = {
    get_settings = function (self)
        local extra = self.extra
        return {
            width = extra.width,
            height = extra.height,
            bpp = extra.bpp,
            zoom = extra.zoom,
            ppdir = extra.ppdir,
            flipx = extra.flipx,
            flipy = extra.flipy,
        }
    end,
    
    input_change = function (self, ind)
        local h = self:get_linked_input(ind)
        if ind == 2 then
            if h then
                local cfg, s = h:readfile()
                s, cfg = pcall(loadstring, "local cfg = " .. cfg .. "\nreturn cfg\n")
                if s then
                    self:apply_config(cfg)
                    self.extra.fb:prepare()
                    self.extra.fb:draw()
                end
            end
            return
        end
        
        if h then h.getnextbyte = dalosp.framebuffer.getnextbyte end
        self:apply_config{}
        self.extra.fb:prepare()
        self.extra.fb:draw()
    end,
    
    activate = function (self)
        self.extra.dlg:show()
    end,
    
    configure = function (self)
        local extra = self.extra
        invert_lookup = {
            [1] = 0,
            [2] = 1,
            [4] = 2,
            [8] = 3,
            [24] = 4,
            [32] = 5,
        }
        lookup = {
            [0] = 1,
            [1] = 2,
            [2] = 4,
            [3] = 8,
            [4] = 24,
            [5] = 32,
        }
        local owidth, oheight, obpp, oppdir, oflipx, oflipy = extra.width, extra.height, extra.bpp, extra.ppdir, not not extra.flipx, not not extra.flipy
        local cb = function (dlg, pi)
            if pi < 0 then return end
            local width, height, bpp, dir
            width = iup.GetParamParam(dlg, 1).value + 0
            height = iup.GetParamParam(dlg, 2).value + 0
            bpp = iup.GetParamParam(dlg, 3).value + 0
            dir = iup.GetParamParam(dlg, 4).value + 0
            flipx = (iup.GetParamParam(dlg, 5).value + 0) ~= 0
            flipy = (iup.GetParamParam(dlg, 6).value + 0) ~= 0
            self:apply_config{ width = width, height = height, bpp = lookup[bpp], dir = dir, flipx = flipx, flipy = flipy }
            self.extra.fb:prepare()
            self.extra.fb:draw()
        end
        local s, nname = iup.GetParam(self.name .. " configuration", cb, [[
New name: %s
Width: %i
Height: %i
Bpp: %l|1 bpp|2 bpp|4 bpp|8 bpp|24 bpp|32 bpp|
Packed Pixels: %l|Little Endian|Big Endian|
Flip X axis: %b
Flip Y axis: %b
]], self.name, owidth, oheight, invert_lookup[obpp], oppdir, oflipx and 1 or 0, oflipy and 1 or 0)
        if not s then
            self:apply_config{ width = owidth, height = oheight, bpp = obpp, ppdir = oppdir, flipx = oflipx, flipy = oflipy }
            self.extra.fb:prepare()
            self.extra.fb:draw()
        else
            self.name = nname
        end
    end,
    
    apply_config = function (self, cfg)
        local extra = self.extra
        local fb = extra.fb
        local h = self:get_linked_input(1)
        if cfg.width then extra.width = cfg.width end
        if cfg.height then extra.height = cfg.height end
        if cfg.bpp then extra.bpp = cfg.bpp end
        if cfg.ppdir then extra.ppdir = cfg.ppdir end
        if cfg.flipx then extra.flipx = cfg.flipx end
        if cfg.flipy then extra.flipy = cfg.flipy end
        if cfg.zoom then extra.zoom = cfg.zoom end
        local zoom = 2 ^ extra.zoom
        local posx = fb.posx
        local posy = fb.posy
        local dx = fb.dx + 0
        local dy = fb.dy + 0
        local fw = math.floor(extra.width * zoom)
        local fh = math.floor(extra.height * zoom)
        if dx >= (fb.xmax - fb.xmin) then posx = math.floor((fw - dx) / 2) end
        if dy >= (fb.ymax - fb.ymin) then posy = math.floor((fh - dy) / 2) end
        fb.xmax = fw
        fb.ymax = fh
        cfg = {
            h = h,
            width = extra.width,
            height = extra.height,
            bpp = extra.bpp,
            ppdir = extra.ppdir,
            flipx = extra.flipx,
            flipy = extra.flipy,
            zoom = zoom,
            x = -posx,
            y = -posy,
            fw = fw,
            fh = fh,
        }
        fb.cfg = cfg
        local cvwidth, cvheight = fb.width or 0, fb.height or 0
        cvwidth, cvheight = cvwidth + 0, cvheight + 0
    end,
    
    getnextbyte = function (h)
        return h:tell() ~= h:getsize() and h:readU8() or 0
    end,
    
    getbit = function (cfg)
        local rc
        local h = cfg.h
        local stateful = cfg.stateful
        if cfg.bpp >= 8 then return end
        stateful = cfg.stateful
        if not stateful or bit.band(stateful, 0x7f) == 0 then
            stateful = h:getnextbyte() * 2 + 1
        else
            stateful = stateful * 2
        end
        cfg.stateful = stateful
        return bit.band(bit.rshift(stateful, 8), 1)
    end,
    
    getnextpixel = function (cfg)
        local rc
        local r, g, b
        local h = cfg.h
        local getbit = function() return dalosp.framebuffer.getbit(cfg) end
        if cfg.bpp == 1 then
            rc = getbit() * 255
            r, g, b = rc, rc, rc
        elseif cfg.bpp == 2 then
            rc = getbit() * 2
            rc = (rc + getbit()) * 255 / 3
            r, g, b = rc, rc, rc
        elseif cfg.bpp == 4 then
            rc = getbit() * 8
            rc = rc + getbit() * 4
            rc = rc + getbit() * 2
            rc = (rc + getbit()) * 255 / 15
            r, g, b = rc, rc, rc
        elseif cfg.bpp == 8 then
            rc = h:getnextbyte()
            r, g, b = rc, rc, rc
        elseif cfg.bpp == 24 then
            r = h:getnextbyte()
            g = h:getnextbyte()
            b = h:getnextbyte()
        elseif cfg.bpp == 32 then
            r = h:getnextbyte()
            g = h:getnextbyte()
            b = h:getnextbyte()
            h:getnextbyte()
        end
        return r, g, b
    end,
    
    prepare = function (self)
        local cfg = self.cfg
        local h = cfg.h
        local width = cfg.width
        local height = cfg.height
        local bpp = cfg.bpp
        local ppdir = cfg.ppdir
        local flipx = cfg.flipx
        local flipy = not cfg.flipy
        local cim = im.ImageCreate(width, height, im.RGB, im.BYTE)
        self.cim = cim
        cim:Clear()
        if not h then return iup.DEFAULT end
        local getnextpixel = self.getnextpixel

        h:seek(0)
        cfg.stateful = 0
        local r, g, b = cim[0], cim[1], cim[2]
        
        for y = 0, height - 1 do
            for x = 0, width - 1 do
                local px, py = flipx and width - x - 1 or x, flipy and height - y - 1 or y
                r[py][px], g[py][px], b[py][px] = getnextpixel(cfg)
            end
        end
        
        return iup.DEFAULT
    end,
    
    draw = function (self)
        local cvdb = self.cvdb
        if not cvdb then return iup.DEFAULT end
        cvdb:Clear()
        local cim = self.cim
        local cfg = self.cfg
        cim:cdCanvasPutImageRect(cvdb, cfg.x, cvdb:InvertYAxis(cfg.y + cfg.fh), cfg.fw, cfg.fh, 0, 0, 0, 0)
        cvdb:Flush()
    end,
    
    resize_cb = function (self, width, height)
        self.dx = width
        self.dy = height
        self.posx = self.posx
        self.posy = self.posy
        iupep.dbuffer.resize_cb(self, width, height)
        self.obj:apply_config{}
        self:draw()
    end,
    
    fimg2canvas = function (self, ix, iy)
        local cfg = self.cfg
        local cx, cy
        return ix + cfg.x, iy + cfg.y
    end,
    
    canvas2fimg = function (self, cx, cy)
        local cfg = self.cfg
        return cx - cfg.x, cy - cfg.y
    end,
    
    img2canvas = function (self, ix, iy)
        local cfg = self.cfg
        return math.floor(ix * cfg.zoom + cfg.x), math.floor(iy * cfg.zoom + cfg.y)
    end,
    
    canvas2img = function (self, cx, cy)
        local cfg = self.cfg
        return math.floor((cx - cfg.x) / cfg.zoom), math.floor((cy - cfg.y) / cfg.zoom)
    end,
    
    scroll_cb = function (self, op, posx, posy)
        self:resize_cb(self.width, self.height)
    end,
    
    wheel_cb = function (self, delta, x, y, status)
        local ox, oy = self:canvas2img(x, y)
        local opx, opy = self.cfg.x, self.cfg.y
        self.obj:apply_config { zoom = self.obj.extra.zoom + (delta / 10) }
        local nx, ny = self:img2canvas(ox, oy)
        local dx, dy = ox - nx, oy - ny
        self.posx, self.posy = -opx - dx, -opy - dy
        self:resize_cb(self.width, self.height)
    end,
    
    motion_cb = function (self, x, y)
        local ox, oy = self:canvas2img(x, y)
        local nx, ny = self:img2canvas(ox, oy)
    end,
    
    create = function (d, tab, settings)
        tab.ninputs = 2
        tab.noutputs = 0
        tab.otype = dalos.objtype.LUA_VIEWER
        tab.activate = dalosp.framebuffer.activate
        tab.configure = dalosp.framebuffer.configure
        tab.input_change = dalosp.framebuffer.input_change
        tab.default_name = "Framebuffer"
        tab.ntype = "Framebuffer"
        tab.get_settings = dalosp.framebuffer.get_settings
        local extra = {
            width = settings.width or 256,
            height = settings.height or 256,
            bpp = settings.bpp or 32,
            ppdir = settings.dir or 0,
            flipx = settings.flipx,
            flipy = settings.flipy,
            zoom = settings.zoom or 0,
        }
        
        local obj = dalos.object(d, tab, extra)
        
        obj.apply_config = dalosp.framebuffer.apply_config

        local fb = iup.canvas {
            expand = "Yes",
            font = "Courier, 8",
            action = iupep.dbuffer.action,
            map_cb = iupep.dbuffer.map_cb,
            unmap_cb = iupep.dbuffer.unmap_cb,
            resize_cb = dalosp.framebuffer.resize_cb,
            motion_cb = dalosp.framebuffer.motion_cb,
            draw = dalosp.framebuffer.draw,
            scroll_cb = dalosp.framebuffer.scroll_cb,
            wheel_cb = dalosp.framebuffer.wheel_cb,
            prepare = dalosp.framebuffer.prepare,
            img2canvas = dalosp.framebuffer.img2canvas,
            canvas2img = dalosp.framebuffer.canvas2img,
            fimg2canvas = dalosp.framebuffer.img2canvas,
            canvas2fimg = dalosp.framebuffer.canvas2img,
            getnextpixel = dalosp.framebuffer.getnextpixel,
            rastersize = extra.width .. "x" .. extra.height,
            scrollbar = "Yes",
            dx = 1,
            dy = 1,
            linex = 1,
            liney = 1,
            xmax = 0,
            ymax = 0,
            xautohide = "No",
            yautohide = "No",
            obj = obj,
        }
        local dlg = iup.dialog {
            iup.vbox {
                fb,
                iup.hbox {
                    iup.fill{},
                    iup.button {
                        action = function () fb.posx, fb.posy = 0, 0 obj:apply_config { zoom = -4 } fb:resize_cb(fb.width, fb.height) end,
                        title = "1:16",
                    },
                    iup.fill{},
                    iup.button {
                        action = function () fb.posx, fb.posy = 0, 0 obj:apply_config { zoom = -3 } fb:resize_cb(fb.width, fb.height) end,
                        title = "1:8",
                    },
                    iup.fill{},
                    iup.button {
                        action = function () fb.posx, fb.posy = 0, 0 obj:apply_config { zoom = -2 } fb:resize_cb(fb.width, fb.height) end,
                        title = "1:4",
                    },
                    iup.fill{},
                    iup.button {
                        action = function () fb.posx, fb.posy = 0, 0 obj:apply_config { zoom = -1 } fb:resize_cb(fb.width, fb.height) end,
                        title = "1:2",
                    },
                    iup.fill{},
                    iup.button {
                        action = function () fb.posx, fb.posy = 0, 0 obj:apply_config { zoom = 0 } fb:resize_cb(fb.width, fb.height) end,
                        title = "1:1",
                    },
                    iup.fill{},
                    iup.button {
                        action = function () fb.posx, fb.posy = 0, 0 obj:apply_config { zoom = 1 } fb:resize_cb(fb.width, fb.height) end,
                        title = "2:1",
                    },
                    iup.fill{},
                    iup.button {
                        action = function () fb.posx, fb.posy = 0, 0 obj:apply_config { zoom = 2 } fb:resize_cb(fb.width, fb.height) end,
                        title = "4:1",
                    },
                    iup.fill{},
                    iup.button {
                        action = function () fb.posx, fb.posy = 0, 0 obj:apply_config { zoom = 3 } fb:resize_cb(fb.width, fb.height) end,
                        title = "8:1",
                    },
                    iup.fill{},
                    iup.button {
                        action = function () fb.posx, fb.posy = 0, 0 obj:apply_config { zoom = 4 } fb:resize_cb(fb.width, fb.height) end,
                        title = "16:1",
                    },
                    iup.fill{},
                },
            },
            size = "320x200",
            title = obj.name,
            shrink = "Yes",
        }
        extra.dlg = dlg
        extra.fb = fb
        
        obj:apply_config{}
        fb:prepare()
        fb:draw()
        
        return obj
    end,
}

dalos.framebuffer = dalosp.framebuffer.create
dalos:register_obj("Framebuffer", dalos.framebuffer, "Basic Viewers")