var shape = use('shape2d')
var text2d = use('text2d')

var S = 60
var GW = S * 8
var GH = S * 8

var light_color = {r: 0.93, g: 0.93, b: 0.85, a: 1}
var dark_color = {r: 0.45, g: 0.55, b: 0.35, a: 1}
var select_color = {r: 1, g: 0.84, b: 0, a: 1}
var valid_color = {r: 0.6, g: 0.8, b: 0.4, a: 1}
var hover_color = {r: 0.8, g: 0.85, b: 0.6, a: 1}

var piece_letter = {
  king: "K", queen: "Q", rook: "R",
  bishop: "B", knight: "N", pawn: "P"
}
var white_text = {r: 1, g: 1, b: 1, a: 1}
var black_text = {r: 0.1, g: 0.1, b: 0.1, a: 1}

var board_shapes = []
var piece_labels = {}
var status_label = null
var next_id = 0

function init(grid) {
  var bx = 0, by = 0, row = null, col = null
  for (by = 0; by < 8; by++) {
    row = []
    for (bx = 0; bx < 8; bx++) {
      col = ((bx + by) & 1) ? dark_color : light_color
      row[] = shape.rect({
        pos: {x: bx * S + S / 2, y: by * S + S / 2},
        width: S, height: S,
        fill: {r: col.r, g: col.g, b: col.b, a: col.a},
        plane: 'game', layer: 0
      })
    }
    board_shapes[] = row
  }

  next_id = 0
  grid.each(function(p) {
    next_id++
    p._id = next_id
    piece_labels[text(next_id)] = text2d({
      text: piece_letter[p.kind],
      pos: {x: p.coord[0] * S + S / 2, y: p.coord[1] * S + S / 2},
      size: 36,
      color: (p.colour == 'white') ? white_text : black_text,
      plane: 'game', layer: 1
    })
  })

  status_label = text2d({
    text: "White's turn", pos: {x: 10, y: GH - 20},
    plane: 'hud', size: 14, color: {r: 1, g: 1, b: 1, a: 1}
  })
}

function sync_pieces(grid) {
  var keys = array(piece_labels)
  var i = 0
  for (i = 0; i < length(keys); i++) {
    piece_labels[keys[i]].visible = false
  }
  grid.each(function(p) {
    var lbl = piece_labels[text(p._id)]
    if (!lbl) return
    lbl.pos.x = p.coord[0] * S + S / 2
    lbl.pos.y = p.coord[1] * S + S / 2
    lbl.visible = true
  })
}

function rebuild_pieces(grid) {
  var keys = array(piece_labels)
  var i = 0
  for (i = 0; i < length(keys); i++) {
    piece_labels[keys[i]].visible = false
  }
  grid.each(function(p) {
    var key = text(p._id)
    var lbl = piece_labels[key]
    if (!lbl) {
      lbl = text2d({
        text: piece_letter[p.kind],
        pos: {x: p.coord[0] * S + S / 2, y: p.coord[1] * S + S / 2},
        size: 36,
        color: (p.colour == 'white') ? white_text : black_text,
        plane: 'game', layer: 1
      })
      piece_labels[key] = lbl
    }
    lbl.pos.x = p.coord[0] * S + S / 2
    lbl.pos.y = p.coord[1] * S + S / 2
    lbl.text = piece_letter[p.kind]
    lbl.visible = true
  })
}

function highlight(selectPos, validMoves, hover_gx, hover_gy) {
  var x = 0, y = 0, col = null
  for (y = 0; y < 8; y++) {
    for (x = 0; x < 8; x++) {
      col = ((x + y) & 1) ? dark_color : light_color
      board_shapes[y][x].fill = {r: col.r, g: col.g, b: col.b, a: col.a}
    }
  }

  if (hover_gx >= 0 && hover_gx < 8 && hover_gy >= 0 && hover_gy < 8) {
    board_shapes[hover_gy][hover_gx].fill = {
      r: hover_color.r, g: hover_color.g, b: hover_color.b, a: hover_color.a
    }
  }

  if (!selectPos) return

  board_shapes[selectPos[1]][selectPos[0]].fill = {
    r: select_color.r, g: select_color.g, b: select_color.b, a: select_color.a
  }

  var i = 0, m = null
  for (i = 0; i < length(validMoves); i++) {
    m = validMoves[i]
    board_shapes[m[1]][m[0]].fill = {
      r: valid_color.r, g: valid_color.g, b: valid_color.b, a: valid_color.a
    }
  }
}

function set_status(msg) {
  status_label.text = msg
}

return {
  S: S, GW: GW, GH: GH,
  init: init,
  sync_pieces: sync_pieces,
  rebuild_pieces: rebuild_pieces,
  highlight: highlight,
  set_status: set_status
}