// Copyright 2019 The Pigweed Authors
//
// Licensed under the Apache License, Version 2.0 (the "License"); you may not
// use this file except in compliance with the License. You may obtain a copy of
// the License at
//
//     https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
// License for the specific language governing permissions and limitations under
// the License.

#include "pw_string/format.h"

#include <cstdarg>

#include "gtest/gtest.h"
#include "pw_span/span.h"

namespace pw::string {
namespace {

TEST(Format, ValidFormatString_Succeeds) {
  char buffer[32];
  auto result = Format(buffer, "-_-");

  EXPECT_EQ(OkStatus(), result.status());
  EXPECT_EQ(3u, result.size());
  EXPECT_STREQ("-_-", buffer);
}

TEST(Format, ValidFormatStringAndArguments_Succeeds) {
  char buffer[32];
  auto result = Format(buffer, "%d4%s", 123, "5");

  EXPECT_EQ(OkStatus(), result.status());
  EXPECT_EQ(5u, result.size());
  EXPECT_STREQ("12345", buffer);
}

TEST(Format, EmptyBuffer_ReturnsResourceExhausted) {
  auto result = Format(span<char>(), "?");

  EXPECT_EQ(Status::ResourceExhausted(), result.status());
  EXPECT_EQ(0u, result.size());
}

TEST(Format, FormatLargerThanBuffer_ReturnsResourceExhausted) {
  char buffer[5];
  auto result = Format(buffer, "2big!");

  EXPECT_EQ(Status::ResourceExhausted(), result.status());
  EXPECT_EQ(4u, result.size());
  EXPECT_STREQ("2big", buffer);
}

TEST(Format, ArgumentLargerThanBuffer_ReturnsResourceExhausted) {
  char buffer[5];
  auto result = Format(buffer, "%s", "2big!");

  EXPECT_EQ(Status::ResourceExhausted(), result.status());
  EXPECT_EQ(4u, result.size());
  EXPECT_STREQ("2big", buffer);
}

PW_PRINTF_FORMAT(2, 3)
StatusWithSize CallFormatWithVaList(span<char> buffer, const char* fmt, ...) {
  va_list args;
  va_start(args, fmt);

  StatusWithSize result = FormatVaList(buffer, fmt, args);

  va_end(args);
  return result;
}

TEST(Format, CallFormatWithVaList_CallsCorrectFormatOverload) {
  char buffer[8];
  auto result = CallFormatWithVaList(buffer, "Yo%s", "?!");

  EXPECT_EQ(OkStatus(), result.status());
  EXPECT_EQ(4u, result.size());
  EXPECT_STREQ("Yo?!", buffer);
}

TEST(FormatString, Append) {
  InlineString<6> string;
  EXPECT_EQ(OkStatus(), Format(string, "-_-"));
  EXPECT_EQ("-_-", string);

  EXPECT_EQ(OkStatus(), Format(string, "%d", 123));
  EXPECT_EQ("-_-123", string);

  EXPECT_EQ(Status::ResourceExhausted(), Format(string, "%d", 1));
  EXPECT_EQ("-_-123", string);
}

TEST(FormatString, EmptyString) {
  InlineString<0> string;
  EXPECT_EQ(Status::ResourceExhausted(), Format(string, "-_-"));
  EXPECT_EQ("", string);
}

TEST(FormatString, Truncates) {
  InlineString<5> string;
  EXPECT_EQ(Status::ResourceExhausted(), Format(string, "1%s", "23456"));
  EXPECT_EQ("12345", string);
}

TEST(FormatString, Overwrite) {
  InlineString<6> string("???");
  EXPECT_EQ(OkStatus(), FormatOverwrite(string, "-_-"));
  EXPECT_EQ("-_-", string);
}

template <Status (&kFunction)(InlineString<>&, const char*, va_list)>
PW_PRINTF_FORMAT(2, 3)
Status CallInlineString(InlineString<>& string, const char* fmt, ...) {
  va_list args;
  va_start(args, fmt);

  Status result = kFunction(string, fmt, args);

  va_end(args);
  return result;
}

TEST(FormatString, CallFormatWithVaList_CallsCorrectFormatOverload) {
  InlineString<8> string;
  Status result = CallInlineString<FormatVaList>(string, "Yo%s %d", "?!", 5);

  EXPECT_EQ(OkStatus(), result);
  EXPECT_EQ(6u, string.size());
  EXPECT_EQ("Yo?! 5", string);
}

TEST(FormatString, OverwriteVaList) {
  InlineString<8> string("blah");
  Status result = CallInlineString<FormatOverwriteVaList>(string, "why%c", '?');

  EXPECT_EQ(OkStatus(), result);
  EXPECT_EQ(4u, string.size());
  EXPECT_EQ("why?", string);
}

}  // namespace
}  // namespace pw::string