load "iupe-dbuffer.lua"

dalosp.framebuffer = {
    get_settings = function (self)
        return { width = self.extra.width, height = self.extra.height, bpp = self.extra.bpp }
    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) end
            end
            return
        end
        
        if h then h.getnextbyte = dalosp.framebuffer.getnextbyte end
        self:apply_config{}
    end,
    
    activate = function (self)
        self.extra.dlg:show()
    end,
    
    configure = function (self)
        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 = self.extra.width, self.extra.height, self.extra.bpp, self.extra.ppdir
        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
            self:apply_config{ width = width, height = height, bpp = lookup[bpp], dir = dir }
        end
        local s, nname, width, height, bpp, ppdir = iup.GetParam(self.name .. " configuration", cb, "New name: %s\nWidth: %i\nHeight: %i\nBpp: %l|1 bpp|2 bpp|4 bpp|8 bpp|24 bpp|32 bpp|\nDirection: %l|Little Endian|Big Endian|\n", self.name, self.extra.width, self.extra.height, invert_lookup[self.extra.bpp], self.extra.ppdir)
        if not s then
            self:apply_config{ width = owidth, height = oheight, bpp = obpp, ppdir = oppdir }
        else
            self.name = nname
        end
    end,
    
    apply_config = function (self, cfg)
        local fb = self.extra.fb
        local h = self:get_linked_input(1)
        if cfg.width then self.extra.width = cfg.width end
        if cfg.height then self.extra.height = cfg.height end
        if cfg.bpp then self.extra.bpp = cfg.bpp end
        if cfg.ppdir then self.extra.ppdir = cfg.ppdir end
        fb.cfg = { h = h, width = self.extra.width, height = self.extra.height, bpp = self.extra.bpp }
        fb:prepare()
        fb:draw()
        fb:action()
    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 = 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 or x, flipy and height - y 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()        
        self.cim:cdCanvasPutImageRect(cvdb, 0, 0, 0, 0, 0, 0, 0, 0) -- use default values
    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 }
        
        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 = iupep.dbuffer.resize_cb,
            draw = dalosp.framebuffer.draw,
            prepare = dalosp.framebuffer.prepare,
            getnextpixel = dalosp.framebuffer.getnextpixel,
            rastersize = extra.width .. "x" .. extra.height,
        }
        local dlg = iup.dialog {
            fb,
            size = "320x200",
            title = obj.name,
            shrink = "Yes",
        }
        extra.dlg = dlg
        extra.fb = fb
        
        obj:apply_config{}
        
        return obj
    end,
}

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