#include "line.hh"

#include "io_test_helper.hh"

#include <cstddef>
#include <gtest/gtest.h>
#include <limits>
#include <utility>

TEST(line, empty) {
  auto reader = line::open(io::memory(""));
  EXPECT_EQ(0, reader->number());
  auto line = reader->read();
  ASSERT_FALSE(line.has_value());
  EXPECT_EQ(io::ReadError::Eof, line.error());
  EXPECT_EQ(0, reader->number());
}

TEST(line, one_line) {
  auto reader = line::open(io::memory("foo"));
  EXPECT_EQ(0, reader->number());
  auto line = reader->read();
  ASSERT_TRUE(line.has_value());
  EXPECT_EQ("foo", line.value());
  EXPECT_EQ(1, reader->number());
  line = reader->read();
  ASSERT_FALSE(line.has_value());
  EXPECT_EQ(io::ReadError::Eof, line.error());
  EXPECT_EQ(1, reader->number());
}

TEST(line, many_lines) {
  auto reader = line::open(io::memory("foo\nbar\nfoobar\n"));
  EXPECT_EQ(0, reader->number());
  auto line = reader->read();
  ASSERT_TRUE(line.has_value());
  EXPECT_EQ("foo", line.value());
  EXPECT_EQ(1, reader->number());
  line = reader->read();
  ASSERT_TRUE(line.has_value());
  EXPECT_EQ("bar", line.value());
  EXPECT_EQ(2, reader->number());
  line = reader->read();
  ASSERT_TRUE(line.has_value());
  EXPECT_EQ("foobar", line.value());
  EXPECT_EQ(3, reader->number());
  line = reader->read();
  ASSERT_FALSE(line.has_value());
  EXPECT_EQ(io::ReadError::Eof, line.error());
  EXPECT_EQ(3, reader->number());
}

TEST(line, many_lines_mixed) {
  auto reader = line::open(io::memory("foo\r\nbar\rfoobar\n"));
  EXPECT_EQ(0, reader->number());
  auto line = reader->read();
  ASSERT_TRUE(line.has_value());
  EXPECT_EQ("foo", line.value());
  EXPECT_EQ(1, reader->number());
  line = reader->read();
  ASSERT_TRUE(line.has_value());
  EXPECT_EQ("bar", line.value());
  EXPECT_EQ(2, reader->number());
  line = reader->read();
  ASSERT_TRUE(line.has_value());
  EXPECT_EQ("foobar", line.value());
  EXPECT_EQ(3, reader->number());
  line = reader->read();
  ASSERT_FALSE(line.has_value());
  EXPECT_EQ(io::ReadError::Eof, line.error());
  EXPECT_EQ(3, reader->number());
}

TEST(line, empty_line) {
  auto reader = line::open(io::memory("\n"));
  EXPECT_EQ(0, reader->number());
  auto line = reader->read();
  ASSERT_TRUE(line.has_value());
  EXPECT_EQ("", line.value());
  EXPECT_EQ(1, reader->number());
  line = reader->read();
  ASSERT_FALSE(line.has_value());
  EXPECT_EQ(io::ReadError::Eof, line.error());
  EXPECT_EQ(1, reader->number());
}

TEST(line, max_line) {
  auto reader = line::open(io::memory("012345678901234567890123456789"), 10);
  EXPECT_EQ(0, reader->number());
  auto line = reader->read();
  ASSERT_TRUE(line.has_value());
  EXPECT_EQ("0123456789", line.value());
  EXPECT_EQ(1, reader->number());
  line = reader->read();
  ASSERT_TRUE(line.has_value());
  EXPECT_EQ("0123456789", line.value());
  EXPECT_EQ(2, reader->number());
  line = reader->read();
  ASSERT_TRUE(line.has_value());
  EXPECT_EQ("0123456789", line.value());
  EXPECT_EQ(3, reader->number());
  line = reader->read();
  ASSERT_FALSE(line.has_value());
  EXPECT_EQ(io::ReadError::Eof, line.error());
  EXPECT_EQ(3, reader->number());
}

TEST(line, read_error) {
  auto reader = line::open(
      io_make_breaking(io::memory("foo bar fum\nfim zam"), /* offset */ 5));
  auto line = reader->read();
  ASSERT_FALSE(line.has_value());
  EXPECT_EQ(io::ReadError::Error, line.error());
}

TEST(line, read_error_newline) {
  auto reader = line::open(
      io_make_breaking(io::memory("foo bar\r\nfim zam"), /* offset */ 8));
  auto line = reader->read();
  ASSERT_FALSE(line.has_value());
  EXPECT_EQ(io::ReadError::Error, line.error());
}

TEST(line, blocky) {
  auto reader = line::open(io_make_max_block(io::memory("foo bar\r\nfim zam"),
                                             /* max_block_size */ 1));
  auto line = reader->read();
  ASSERT_TRUE(line.has_value());
  EXPECT_EQ("foo bar", line.value());
  line = reader->read();
  ASSERT_TRUE(line.has_value());
  EXPECT_EQ("fim zam", line.value());
  line = reader->read();
  ASSERT_FALSE(line.has_value());
  EXPECT_EQ(io::ReadError::Eof, line.error());
}

TEST(line, blocky_newline) {
  auto reader = line::open(io_make_max_block(io::memory("foo bar\r\nfim zam"),
                                             /* max_block_size */ 8));
  auto line = reader->read();
  ASSERT_TRUE(line.has_value());
  EXPECT_EQ("foo bar", line.value());
  line = reader->read();
  ASSERT_TRUE(line.has_value());
  EXPECT_EQ("fim zam", line.value());
  line = reader->read();
  ASSERT_FALSE(line.has_value());
  EXPECT_EQ(io::ReadError::Eof, line.error());
}

TEST(line, eof_newline) {
  auto reader = line::open(io::memory("foo bar\r"));
  auto line = reader->read();
  ASSERT_TRUE(line.has_value());
  EXPECT_EQ("foo bar", line.value());
  line = reader->read();
  ASSERT_FALSE(line.has_value());
  EXPECT_EQ(io::ReadError::Eof, line.error());
}

TEST(line, max_newline) {
  auto reader = line::open(io::memory("foo bar\r"), 6);
  auto line = reader->read();
  ASSERT_TRUE(line.has_value());
  EXPECT_EQ("foo ba", line.value());
  line = reader->read();
  ASSERT_TRUE(line.has_value());
  EXPECT_EQ("r", line.value());
  line = reader->read();
  ASSERT_FALSE(line.has_value());
  EXPECT_EQ(io::ReadError::Eof, line.error());
}

TEST(line, max_line_overflow) {
  EXPECT_DEATH_IF_SUPPORTED(
      {
        std::ignore =
            line::open(io::memory(""), std::numeric_limits<size_t>::max());
      },
      "");
}