defmodule Mix.Tasks.Geoip.ImportUnitTest do
  use ExUnit.Case, async: true

  alias Mix.Tasks.Geoip.Import

  describe "parse_geoname_id/1" do
    test "empty string returns nil" do
      assert nil == Import.parse_geoname_id("")
    end

    test "valid integer returns the integer" do
      assert 12_345 == Import.parse_geoname_id("12345")
    end

    test "invalid format returns nil" do
      assert nil == Import.parse_geoname_id("abc")
    end

    test "partial integer parses leading number" do
      assert 123 == Import.parse_geoname_id("123abc")
    end
  end

  describe "parse_cidr/1" do
    test "valid IPv4 /24 CIDR" do
      assert {:ok, start_int, end_int} = Import.parse_cidr("192.168.1.0/24")
      # 192.168.1.0 = 3232235776
      assert start_int == 3_232_235_776
      # 192.168.1.255 = 3232236031
      assert end_int == 3_232_236_031
      assert end_int - start_int == 255
    end

    test "valid /32 host address" do
      assert {:ok, same, same} = Import.parse_cidr("10.0.0.1/32")
      assert same == 10 * 16_777_216 + 1
    end

    test "valid /0 full range" do
      assert {:ok, 0, end_int} = Import.parse_cidr("0.0.0.0/0")
      assert end_int == 4_294_967_295
    end

    test "invalid CIDR returns :error" do
      assert :error == Import.parse_cidr("not a cidr")
      assert :error == Import.parse_cidr("192.168.1.0")
      assert :error == Import.parse_cidr("256.256.256.256/24")
    end
  end

  describe "parse_block_line/1" do
    test "well-formed line with geoname_id" do
      line = "192.168.1.0/24,12345,67890,,,,0,1,,\n"
      result = Import.parse_block_line(line)

      assert result.network == "192.168.1.0/24"
      assert result.geoname_id == 12_345
      assert result.registered_country_geoname_id == 67_890
    end

    test "empty geoname_id falls back to registered" do
      line = "192.168.1.0/24,,67890,,,,,,,\n"
      result = Import.parse_block_line(line)

      assert result.geoname_id == 67_890
      assert result.registered_country_geoname_id == 67_890
    end

    test "both empty returns nil" do
      line = "192.168.1.0/24,,,,,,,,,\n"
      assert nil == Import.parse_block_line(line)
    end

    test "malformed line returns nil" do
      assert nil == Import.parse_block_line("no commas\n")
    end

    test "invalid CIDR returns nil" do
      line = "not-a-cidr,12345,67890,,\n"
      assert nil == Import.parse_block_line(line)
    end
  end

  describe "parse_location_line/1" do
    test "parses a standard location row" do
      line = "5332921,en,NA,North America,US,United States,CA,California,,,San Jose,,America/Los_Angeles,false"
      result = Import.parse_location_line(line)

      assert result.geoname_id == 5_332_921
      assert result.country_code == "US"
      assert result.country_name == "United States"
      assert result.city_name == "San Jose"
      assert result.subdivision_1_name == "California"
    end

    test "empty city becomes nil" do
      line = "5332921,en,NA,North America,US,United States,CA,California,,,,,,false"
      result = Import.parse_location_line(line)

      assert result.city_name == nil
    end

    test "missing country_code skips the row" do
      line = "5332921,en,NA,,,United States,CA,California,,,San Jose,,tz,false"
      assert nil == Import.parse_location_line(line)
    end

    test "missing geoname_id skips the row" do
      line = ",en,NA,North America,US,United States,CA,California,,,San Jose,,tz,false"
      assert nil == Import.parse_location_line(line)
    end

    test "malformed short line returns nil" do
      assert nil == Import.parse_location_line("too,few,fields")
    end
  end

  describe "build_block_entry/3" do
    test "nil geoname_id returns nil" do
      assert nil == Import.build_block_entry("192.168.1.0/24", nil, 67_890)
    end

    test "invalid CIDR returns nil" do
      assert nil == Import.build_block_entry("garbage", 12_345, 67_890)
    end

    test "valid inputs produce a complete entry" do
      entry = Import.build_block_entry("10.0.0.0/8", 12_345, 67_890)

      assert entry.network == "10.0.0.0/8"
      assert entry.geoname_id == 12_345
      assert entry.registered_country_geoname_id == 67_890
      assert entry.start_ip_int < entry.end_ip_int
    end
  end
end