---------------------------------------------------------------------------
-- @author Donald Ephraim Curtis <dcurtis@cs.uiowa.edu>
-- @author Julien Danjou <julien@danjou.info>
-- @copyright 2009 Donald Ephraim Curtis
-- @copyright 2008 Julien Danjou
-- @release @AWESOME_VERSION@
---------------------------------------------------------------------------

-- Grab environment we need
local tag = require("awful.tag")
local client = require("awful.client")
local ipairs = ipairs
local math = math
local capi =
{
    mouse = mouse,
    screen = screen,
    mousegrabber = mousegrabber
}

--- Tiled layouts module for awful
-- awful.layout.suit.tile
local tile = {}

local function mouse_resize_handler(c, corner, x, y, orientation)
    local orientation = orientation or "tile"
    local wa = capi.screen[c.screen].workarea
    local mwfact = tag.getmwfact()
    local cursor
    local g = c:geometry()
    local offset = 0
    local x,y
    if orientation == "tile" then
        cursor = "cross"
        if g.height+15 > wa.height then
            offset = g.height * .5
            cursor = "sb_h_double_arrow"
        elseif not (g.y+g.height+15 > wa.y+wa.height) then
            offset = g.height
        end
        capi.mouse.coords({ x = wa.x + wa.width * mwfact, y = g.y + offset })
    elseif orientation == "left" then
        cursor = "cross"
        if g.height+15 >= wa.height then
            offset = g.height * .5
            cursor = "sb_h_double_arrow"
        elseif not (g.y+g.height+15 > wa.y+wa.height) then
            offset = g.height
        end
        capi.mouse.coords({ x = wa.x + wa.width * (1 - mwfact), y = g.y + offset })
    elseif orientation == "bottom" then
        cursor = "cross"
        if g.width+15 >= wa.width then
            offset = g.width * .5
            cursor = "sb_v_double_arrow"
        elseif not (g.x+g.width+15 > wa.x+wa.width) then
            offset = g.width
        end
        capi.mouse.coords({ y = wa.y + wa.height * mwfact, x = g.x + offset})
    else
        cursor = "cross"
        if g.width+15 >= wa.width then
            offset = g.width * .5
            cursor = "sb_v_double_arrow"
        elseif not (g.x+g.width+15 > wa.x+wa.width) then
            offset = g.width
        end
        capi.mouse.coords({ y = wa.y + wa.height * (1 - mwfact), x= g.x + offset })
    end

    capi.mousegrabber.run(function (_mouse)
                              for k, v in ipairs(_mouse.buttons) do
                                  if v then
                                      local fact_x = (_mouse.x - wa.x) / wa.width
                                      local fact_y = (_mouse.y - wa.y) / wa.height
                                      local mwfact

                                      local g = c:geometry()


                                      -- we have to make sure we're not on the last visible client where we have to use different settings.
                                      local wfact
                                      local wfact_x, wfact_y
                                      if (g.y+g.height+15) > (wa.y+wa.height) then
                                          wfact_y = (g.y + g.height - _mouse.y) / wa.height
                                      else
                                          wfact_y = (_mouse.y - g.y) / wa.height
                                      end

                                      if (g.x+g.width+15) > (wa.x+wa.width) then
                                          wfact_x = (g.x + g.width - _mouse.x) / wa.width
                                      else
                                          wfact_x = (_mouse.x - g.x) / wa.width
                                      end


                                      if orientation == "tile" then
                                          mwfact = fact_x
                                          wfact = wfact_y
                                      elseif orientation == "left" then
                                          mwfact = 1 - fact_x
                                          wfact = wfact_y
                                      elseif orientation == "bottom" then
                                          mwfact = fact_y
                                          wfact = wfact_x
                                      else
                                          mwfact = 1 - fact_y
                                          wfact = wfact_x
                                      end

                                      tag.setmwfact(math.min(math.max(mwfact, 0.01), 0.99), tag.selected(c.screen))
                                      client.setwfact(math.min(math.max(wfact,0.01), 0.99), c)
                                      return true
                                  end
                              end
                              return false
                          end, cursor)
end

local function tile_group(cls, wa, orientation, fact, group)
    -- get our orientation right
    local height = "height"
    local width = "width"
    local x = "x"
    local y = "y"
    if orientation == "top" or orientation == "bottom" then
        height = "width"
        width = "height"
        x = "y"
        y = "x"
    end

    -- make this more generic (not just width)
    local available = wa[width] - (group.coord - wa[x])

    -- find our total values
    local total_fact = 0
    local min_fact = 1
    local size = group.size
    for c = group.first,group.last do
        -- determine the width/height based on the size_hint
        local i = c - group.first +1
        local size_hints = cls[c].size_hints
        local size_hint = size_hints["min_"..width] or size_hints["base_"..width] or 0
        size_hint = size_hint + cls[c].border_width*2
        size = math.max(size_hint, size)

        -- calculate the height
        if not fact[i] then
            fact[i] = min_fact
        else
            min_fact = math.min(fact[i],min_fact)
        end
        total_fact = total_fact + fact[i]
    end
    size = math.min(size, available)

    local coord = wa[y]
    local geom = {}
    local used_size = 0
    local unused = wa[height]
    for c = group.first,group.last do
        local i = c - group.first +1
        geom[width] = size - cls[c].border_width * 2
        geom[height] = math.floor(unused * fact[i] / total_fact) - cls[c].border_width * 2
        geom[x] = group.coord
        geom[y] = coord
        geom = cls[c]:geometry(geom)
        coord = coord + geom[height] + cls[c].border_width * 2
        unused = unused - geom[height] - cls[c].border_width * 2
        total_fact = total_fact - fact[i]
        used_size = math.max(used_size, geom[width] + cls[c].border_width * 2)
    end

    return used_size
end

local function do_tile(param, orientation)
    local t = param.tag or tag.selected(param.screen)
    orientation = orientation or "right"

    -- This handles all different orientations.
    local height = "height"
    local width = "width"
    local x = "x"
    local y = "y"
    if orientation == "top" or orientation == "bottom" then
        height = "width"
        width = "height"
        x = "y"
        y = "x"
    end

    local cls = param.clients
    local nmaster = math.min(tag.getnmaster(t), #cls)
    local nother = math.max(#cls - nmaster,0)

    local mwfact = tag.getmwfact(t)
    local wa = param.workarea
    local ncol = tag.getncol(t)

    local data = tag.getdata(t).windowfact

    if not data then
        data = {}
        tag.getdata(t).windowfact = data
    end

    local coord = wa[x]
    local place_master = true
    if orientation == "left" or orientation == "top" then
        -- if we are on the left or top we need to render the other windows first
        place_master = false
    end

    -- this was easier than writing functions because there is a lot of data we need
    for d = 1,2 do
        if place_master and nmaster > 0 then
            local size = wa[width]
            if nother > 0 then
                size = math.min(wa[width] * mwfact, wa[width] - (coord - wa[x]))
            end
            if not data[0] then
                data[0] = {}
            end
            coord = coord + tile_group(cls, wa, orientation, data[0], {first=1, last=nmaster, coord = coord, size = size})
        end

        if not place_master and nother > 0 then
            local last = nmaster

            -- we have to modify the work area size to consider left and top views
            local wasize = wa[width]
            if nmaster > 0 and (orientation == "left" or orientation == "top") then
                wasize = wa[width] - wa[width]*mwfact
            end
            for i = 1,ncol do
                -- Try to get equal width among remaining columns
                local size = math.min( (wasize - (coord - wa[x])) / (ncol - i + 1) )
                local first = last + 1
                last = last + math.floor((#cls - last)/(ncol - i + 1))
                -- tile the column and update our current x coordinate
                if not data[i] then
                    data[i] = {}
                end
                coord = coord + tile_group(cls, wa, orientation, data[i], { first = first, last = last, coord = coord, size = size })
            end
        end
        place_master = not place_master
    end

end

tile.right = {}
tile.right.name = "tile"
tile.right.arrange = do_tile
function tile.right.mouse_resize_handler(c, corner, x, y)
    return mouse_resize_handler(c, corner, x, y)
end

--- The main tile algo, on left.
-- @param screen The screen number to tile.
tile.left = {}
tile.left.name = "tileleft"
function tile.left.arrange(p)
    return do_tile(p, "left")
end
function tile.left.mouse_resize_handler(c, corner, x, y)
    return mouse_resize_handler(c, corner, x, y, "left")
end

--- The main tile algo, on bottom.
-- @param screen The screen number to tile.
tile.bottom = {}
tile.bottom.name = "tilebottom"
function tile.bottom.arrange(p)
    return do_tile(p, "bottom")
end
function tile.bottom.mouse_resize_handler(c, corner, x, y)
    return mouse_resize_handler(c, corner, x, y, "bottom")
end

--- The main tile algo, on top.
-- @param screen The screen number to tile.
tile.top = {}
tile.top.name = "tiletop"
function tile.top.arrange(p)
    return do_tile(p, "top")
end
function tile.top.mouse_resize_handler(c, corner, x, y)
    return mouse_resize_handler(c, corner, x, y, "top")
end

tile.arrange = tile.right.arrange
tile.mouse_resize_handler = tile.right.mouse_resize_handler
tile.name = tile.right.name

return tile