package.cpath = package.cpath .. ";../../target/debug/?.so"
package.path = package.path .. ";../../lua-bindings/?.lua"

local dia = require("diaphragm")

-- TODO: add a way to have modified prototypes of these functions
-- e.g.: local my_blocks = Blocks:new({ default_color = my_color })
--       my_blocks:new({ elements = ... }):draw()

dia.util.eprint("--------------------")

-- TODO: Fanwood has a high baseline, which renders weirdly in the GroupCommit layer,
-- and "Goudy Bookletter 1911" doesn't work
-- local serif_family = "Fanwood"
-- local serif_family = "Latin Modern Math"
-- local serif_family = "Goudy Bookletter 1911 Normal"
local serif_family = "OFL Sorts Mill Goudy"
-- local mono_family = "Fira Mono"
local mono_family = "Iosevka"

local upstream_colors = {
	base04 = "#cccccc",
	base06 = "#ffffff",
	base0B = "#5959ff",
	base0F = "#7f7f7f",
}

local nord_colors = {
	base00 = "#2E3440",
	base01 = "#3B4252",
	base02 = "#434C5E",
	base03 = "#4C566A",
	base04 = "#D8DEE9",
	base05 = "#E5E9F0",
	base06 = "#ECEFF4",
	base07 = "#8FBCBB",
	base08 = "#BF616A",
	base09 = "#D08770",
	base0A = "#EBCB8B",
	base0B = "#A3BE8C",
	base0C = "#88C0D0",
	base0D = "#81A1C1",
	base0E = "#B48EAD",
	base0F = "#5E81AC",
}

-- local colors = upstream_colors
local colors = nord_colors

local active_color = colors.base0B
local background = colors.base06
local light_gray = colors.base04
local dark_gray = colors.base0F

local block_unit_width = 24
local block_height = 36
local block_stroke_width = 2

local normal_margin = 20
local small_margin = 10

local function blocks(params)
	local result = dia.shape(params)

	result.unit_width = result.unit_width or dia.float.new()
	result.default_color = result.default_color or light_gray
	result.default_stroke_width = result.default_stroke_width or block_stroke_width

	result.blocks = dia.util.tbl_map(function(el)
		return dia.rectangle.new({
			fill_color = el.color or result.default_color,
			stroke_width = result.default_stroke_width,
			height = result.height,
			width = result.unit_width * (el.grow or 1),
		})
	end, params.elements)

	function result:draw()
		local len = #self.elements
		assert(len >= 1, "Blocks must have at least 1 element")

		local total_grow = 0
		for _, el in pairs(self.elements) do
			total_grow = total_grow + (el.grow or 1)
		end

		dia.constrain(self.width:eq(self.unit_width * total_grow))

		dia.layout
			.hstack({
				elements = self.blocks,
				top_left = self.top_left,
				bottom_right = self.bottom_right,
				width = self.width,
			})
			:draw()
	end

	return result
end

local function active_txn(params)
	return blocks(dia.util.tbl_extend({
		elements = { {}, {}, {}, {}, {} },
		height = block_height,
		default_color = active_color,
	}, params))
end

local function fixed_blocks(params)
	local elements = {}
	for _ = 1, params.count do
		table.insert(elements, {})
	end
	return blocks({
		elements = elements,
		height = block_height,
		unit_width = block_unit_width,
		default_color = params.color or dark_gray,
	})
end

local function block_list(params)
	local result = dia.shape(params)

	result.delimiter_height = result.delimiter_height or dia.float.new()
	result.font = result.font or dia.text.font({ family = serif_family })

	function result:draw()
		local opening_delimiter = dia.text.new({
			content = "[",
			height = self.delimiter_height,
			font = self.font,
		})

		local closing_delimiter = dia.text.new({
			content = "]",
			height = self.delimiter_height,
			font = self.font,
		})

		local function comma()
			return dia.text.new({
				content = ", ",
				font = self.font,
			})
		end

		local elements = dia.util.list_intersperse_with(comma, self.elements)

		elements = { opening_delimiter, table.unpack(elements) }
		table.insert(elements, closing_delimiter)

		-- TODO: not really elegant
		dia.constrain(self.delimiter_height:eq(self.elements[1].height * 2.5))

		dia.layout
			.hstack({
				elements = elements,
				align = "center",
				top_left = self.top_left,
				bottom_right = self.bottom_right,
			})
			:draw()
	end

	return result
end

local function disk_log_legend(params)
	local result = dia.shape(params)

	local function lines(params)
		local result = dia.shape(params)

		result.ticks = {}
		for _, tick in ipairs(params.ticks) do
			table.insert(
				result.ticks,
				dia.straight_path.new({
					points = {
						{ x = tick, y = result.top },
						{ x = tick, y = result.bottom },
					},
				})
			)
		end

		result.baseline = dia.straight_path.new({
			points = { result.middle_left, result.middle_right },
			width = result.width,
		})

		function result:draw()
			for _, tick in ipairs(self.ticks) do
				tick:draw()
			end
			self.baseline:draw()
		end

		return result
	end

	result.lines = lines({
		ticks = params.ticks,
		top_left = result.top_left,
		height = result.height / 2,
		width = result.width,
	})

	result.font = dia.text.font({ family = serif_family })

	result.labels = {}
	for i = 1, #params.ticks - 1 do
		local label = dia.text.new({
			content = params.labels[i],
			height = (result.height / 2) + result.height / 6,
			top = result.lines.bottom - result.height / 6,
			horiz_center = (params.ticks[i] + params.ticks[i + 1]) / 2,
			font = result.font,
		})
		table.insert(result.labels, label)
	end

	function result:draw()
		self.lines:draw()
		for _, label in ipairs(self.labels) do
			label:draw()
		end
	end

	return result
end

local function disk_log(params)
	local result = dia.shape(params)

	local anchor_ids = {}
	local last_group_id = 0
	local labels = {}
	local elements = {}
	for _, global_spec in pairs(params.elements) do
		for _, spec in pairs(global_spec.elements) do
			local spec_params = spec.params or {}
			for _ = 1, spec.count do
				table.insert(elements, spec_params)
			end
			last_group_id = last_group_id + spec.count
		end
		table.insert(anchor_ids, last_group_id)
		table.insert(labels, global_spec.label)
	end
	result.blocks = blocks({
		elements = elements,
		height = block_height,
		top_left = result.top_left,
		width = result.width,
	})
	result.anchors = { result.left }
	for _, id in pairs(anchor_ids) do
		table.insert(result.anchors, result.blocks.blocks[id].right)
	end

	result.legend = disk_log_legend({
		ticks = result.anchors,
		labels = labels,
		height = normal_margin * 2,
		width = result.width,
		bottom_right = result.bottom_right,
	})
	dia.constraint.below(result.legend, result.blocks, normal_margin)

	function result:draw()
		result.blocks:draw()
		result.legend:draw()
	end

	return result
end

local function layer_entry(params)
	local result = dia.shape(params)

	result.text = params.text or dia.text.new({
		content = params.name .. ": ",
		font = params.font,
	})
	result.text_vert_center = params.text_vert_center or params.content.vert_center

	function result:draw()
		dia.constraint.left_of(self.text, self.content)
		dia.constrain(self.text.vert_center:eq(self.text_vert_center))

		dia.constrain(self.left:eq(self.text.left))
		dia.constrain(self.right:eq(self.content.right))
		dia.constrain(self.top:eq(dia.float.min({ self.text.top, self.content.top })))
		dia.constrain(self.bottom:eq(dia.float.max({ self.text.bottom, self.content.bottom })))

		self.text:draw()
		self.content:draw()
	end

	return result
end

local function layer(params)
	local result = dia.shape(params)

	result.name = result.name or "Layer"
	result.title = dia.text.new({
		content = result.name,
		font = result.title_font,
		top_left = result.top_left + { x = normal_margin, y = normal_margin },
	})
	result.content = result.content or dia.rectangle.new({
		height = 100,
		width = 100,
	})

	-- TODO: seems hacky
	result.right:minimize()

	function result:draw()
		dia.rectangle
			.new({
				top_left = self.top_left,
				bottom_right = self.bottom_right,
				fill_color = background,
			})
			:draw()

		dia.constrain(self.right:eq(self.content.right + normal_margin))
		dia.constraint.below(self.content, self.title)
		dia.constrain(self.left:lt(self.content.left - 150))

		dia.constrain(self.bottom:eq(dia.float.max({ self.title.bottom, self.content.bottom }) + normal_margin))

		self.title:draw()
		self.content:draw()
	end

	return result
end

dia.draw({
	draw = function(self)
		local title_font = dia.text.font({ family = serif_family, size = 48 })
		local entry_font = dia.text.font({ family = mono_family, size = 20 })
		local action_font = dia.text.font({ family = mono_family, height = normal_margin })

		local function action(name)
			return dia.layout.margin_top({
				margin_top = small_margin,
				content = dia.text.new({
					content = '<span foreground="' .. active_color .. '">' .. name .. "</span>",
					font = action_font,
					height = normal_margin,
				}),
			})
		end

		local layer_right = dia.float.new()

		local log_layer_entry_left = dia.float.new()
		local group_commit_entry_left = dia.float.new()
		local disk_log_entry_left = dia.float.new()

		local layers = {
			layer({
				name = "LogAPI",
				title_font = title_font,
				content = dia.layout.margin_right({
					content = layer_entry({
						name = "activeTxn",
						font = entry_font,
						content = active_txn({
							unit_width = block_unit_width,
							left = log_layer_entry_left,
						}),
					}),
				}),
			}),
			action("commit"),
			layer({
				name = "GroupCommit",
				title_font = title_font,
				-- top_left = { x = 20, y = 100 + 40 },
				-- right = layer_right,
				content = dia.layout.margin_right({
					-- HACK: because I know that "GroupCommit" + "commitedTxns:"
					-- takes the most space
					margin_right = 0,
					content = layer_entry({
						name = "commitedTxns",
						font = entry_font,
						content = block_list({
							elements = {
								fixed_blocks({ count = 2 }),
								fixed_blocks({ count = 7 }),
								fixed_blocks({ count = 4 }),
								active_txn({ unit_width = block_unit_width }),
							},
							left = group_commit_entry_left,
						}),
					}),
				}),
			}),
			action("flush"),
			layer({
				name = "DiskLog",
				title_font = title_font,
				-- top_left = { x = 20, y = 100 + 40 },
				right = layer_right,
				content = dia.layout.margin_right({
					margin_right = 0,
					content = layer_entry({
						-- TODO: align to blocks
						name = "disk log",
						font = entry_font,
						content = disk_log({
							elements = {
								{
									-- TODO: seems to fail solving if using other font size within text, or line returns
									label = "header",
									elements = {
										{ count = 1, params = { color = "#000", grow = 11 } },
									},
								},
								{
									label = "data",
									elements = {
										{ count = 2, params = { color = light_gray, grow = 13 + 5 } },
										{ count = 13, params = { color = dark_gray } },
										{ count = 5, params = { color = active_color } },
									},
								},
								{
									label = "available",
									elements = {
										{ count = 1, params = { color = "#fff", grow = 13 + 5 } },
									},
								},
							},
							left = disk_log_entry_left,
						}),
					}),
				}),
			}),
			action("apply"),
			layer({
				name = "Applier",
				title_font = title_font,
				right = layer_right,
			}),
		}

		local figure = dia.layout.vstack({ elements = layers, align = "right" })
		figure:draw()
		dia.constraint.inset(figure, self, { margin = normal_margin })

		local layer_entries_text_right = dia.float.new()
		for _, entry_left in pairs({ log_layer_entry_left, group_commit_entry_left, disk_log_entry_left }) do
			dia.constrain(layer_entries_text_right:eq(entry_left))
		end
	end,

	-- TODO: It currently silently panics if output is not there
	output = {},
})

-- TODO: anyone can use metatable?
--[[
local Blocks = diaphragm.Drawable:new()
Blocks.elements = {}
Blocks.unit_width = diaphragm.float()

function Blocks:draw()
	local len = #self.elements
	assert(len >= 1, "Blocks must have at least 1 element")

	local total_grow = 0
	for el in self.elements do
		total_grow = el.grow or 1
	end

	diaphragm.constrain(self.width == self.unit_width * total_grow)

	local param = self.elements[0]

	-- TODO: this would be written with layout.hstack

	local block = diaphragm.shape.Rectangle:new()
	block.fill(param.color)
	diaphragm.constrain(block.left() == self.left())
	diaphragm.constrain(block.top() == self.top())
	diaphragm.constrain(block.bottom() == self.bottom())
	diaphragm.constrain(block.width() == (param.grow or 1) * self.unit_width)

	block.draw()

	local previous_right = block.right()

	for i = 2, len do
		param = self.elements[i]

		block = diaphragm.shape.Rectangle:new()
		block.fill(param.color)

		diaphragm.constrain(block.left() == previous_right)
		diaphragm.constrain(block.top() == self.top())
		diaphragm.constrain(block.bottom() == self.bottom())
		diaphragm.constrain(block.width() == (param.grow or 1) * self.unit_width)

		block.draw()

		previous_right = block.right()
	end
end

-- Library
----------

local function block(color)
	local res = diaphragm.shape.Rectangle:new()
	res.fill(color)
	return res
end

local function blocks_by_len(count, color)
	local res = {}
	for i = 1, count do
		res[i] = block(color)
	end

	-- TODO: rename cons? Misleading
	diaphragm.cons.same_size(res)
	return diaphragm.layout.hstack(res)
end

local function layer(config)
	local name = config.name or ""
	local entries = config.entries or {}

	-- TODO: how to do it without box?
	-- TODO: implement union or combine
	--       probably combine because
	--       union could remove some
	--       strokes
	return diaphragm.layout.box({})
end

-- Parameters
-------------

local blue = diaphragm.color.from_rgb(0.35, 0.35, 1.)

local active_txn_count = 5

-- Log API
----------

local log_api = layer({
	name = "LogAPI",
	entries = {
		{
			name = "activeTxn",
			content = blocks_by_len(active_txn_count, blue),
		},
	},
})

-- Group Commit
---------------

-- local group_commit = nil

-- Disk Log
-----------

-- local disk_log = nil

-- Applier
----------

-- local applier = nil

diaphragm.draw(diaphragm.layout.vstack({
	log_api,
	-- group_commit,
	-- disk_log,
	-- applier,
})) ]]