local alpine = {}

local utils = require("utils")
local t = require("utils/templater")

-- Returns nil when no failure, otherwise apk's status code
function alpine.init_rootfs(path, alpine_base_version, alpine_version)
	local status = os.execute(t("sudo rm -rf '{{path}}' && mkdir -p '{{path}}'", {path = path}))
	if not (status == 0) then return status end
	local url = t("https://dl-cdn.alpinelinux.org/alpine/v{{base_version}}/releases/x86_64/alpine-minirootfs-{{version}}-x86_64.tar.gz", {
		base_version = alpine_base_version,
		version = alpine_version
	})
	local status = os.execute(t("cd '{{path}}' && wget --no-verbose -O- '{{url}}' | tar zx", { path = path, url = url }))
	if not (status == 0) then return status end
end

function alpine.move_boot(path)
	local status = os.execute(t("sudo rm -rf '{{path}}/../boot' && sudo mv '{{path}}/boot' '{{path}}/../' && sudo mkdir '{{path}}/boot'", {
		path = path,
	}))
	if not (status == 0) then return status end
end

function alpine.make_squashfs(path, output_path)
	local status = os.execute(t("sudo mksquashfs '{{path}}' '{{output_path}}' -comp zstd -Xcompression-level 3 -noappend -quiet && sudo chown $(id -u):$(id -g) '{{output_path}}'", {
		path = path,
		output_path = output_path,
	}))
	if not (status == 0) then return status end
end

function alpine.mkdir(rootfs_path, path)
	local real_path = rootfs_path..path

	local cmd = t("mkdir -p '{{real_path}}'", {
		real_path = real_path,
	})

	-- XXX: Usar lua-posix
	local status = os.execute(cmd)
	if not (status == 0) then return status end
end

function alpine.touch(rootfs_path, path)
	local real_path = rootfs_path..path

	local cmd = t("touch '{{real_path}}'", { real_path = real_path })

	-- XXX: Usar lua-posix
	local status = os.execute(cmd)
	if not (status == 0) then return status end
end

function alpine.write_file(rootfs_path, path, content)
	local real_path = rootfs_path..path

	local cmd = t("mkdir -p '{{real_dirname}}' && test -f '{{real_path}}' || exit 0 && sudo chown $(id -u) '{{real_path}}'", {
		real_path = real_path,
		real_dirname = utils.dirname(real_path),
	})

	-- XXX: Usar lua-posix
	local status = os.execute(cmd)
	if not (status == 0) then return status end

	local file, err = io.open(real_path, "w+")
	if not file then return err end

	file:write(content)
	file:close()
end

function alpine.symlink(rootfs_path, path, target)
	local real_path = rootfs_path..path

	local cmd = t("mkdir -p '{{real_dirname}}' && ln -s '{{target}}' '{{real_path}}'", {
		real_path = real_path,
		target = target,
		real_dirname = utils.dirname(real_path),
	})

	-- XXX: Usar lua-posix
	local status = os.execute(cmd)
	if not (status == 0) then return status end
end

function alpine.chmod(rootfs_path, path, perms)
	local real_path = rootfs_path..path

	local cmd = t("chmod '{{perms}}' '{{real_path}}'", {
		real_path = real_path,
		perms = perms,
	})

	-- XXX: Usar lua-posix
	local status = os.execute(cmd)
	if not (status == 0) then return status end
end

-- Returns nil when no failure, otherwise string error or apk's status code
function alpine.make_world(rootfs_path, packages)
	local err = alpine.symlink(rootfs_path, "/etc/apk/cache", "../../../cache")
	if err then return err end
	local err = alpine.mkdir(rootfs_path, "../cache")
	if err then return err end

	local err = alpine.write_file(rootfs_path,
		"/etc/apk/world",
		utils.join_table(packages, "\n"))
	if err then return err end

	local params = { rootfs_path = rootfs_path }

	local status = os.execute(t("sudo apk upgrade --clean-protected --root  '{{rootfs_path}}'",
		params))
	if not (status == 0) then return status end

	local status = os.execute(t("rm '{{rootfs_path}}/etc/apk/cache'",
		params))
	if not (status == 0) then return status end
end

-- Returns nil when no failure, otherwise status code
function alpine.set_password(rootfs_path, user, password)
	local status = os.execute(t("echo '{{password}}\n{{password}}' | sudo chroot '{{rootfs_path}}' passwd '{{user}}'", {
		password = password,
		rootfs_path = rootfs_path,
		user = user,
	}))
	if not (status == 0) then return status end
end

return alpine