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#include "MavlinkStatustextHandler.hpp"
#include <gtest/gtest.h>

static constexpr uint64_t some_time = 12345678;
static constexpr uint64_t some_other_time = 99999999;
static constexpr auto some_text = "Some short text";
static constexpr auto some_other_text = "Some more short text";
static constexpr uint8_t some_severity = MAV_SEVERITY_CRITICAL;
static constexpr uint8_t some_other_severity = MAV_SEVERITY_INFO;

TEST(MavlinkStatustextHandler, Singles)
{
	MavlinkStatustextHandler handler;

	mavlink_statustext_t statustext1 {};
	statustext1.severity = some_severity;
	strncpy(statustext1.text, some_text, sizeof(statustext1.text));

	EXPECT_FALSE(handler.should_publish_previous(statustext1));
	EXPECT_TRUE(handler.should_publish_current(statustext1, some_time));
	EXPECT_STREQ(handler.log_message().text, some_text);
	EXPECT_EQ(handler.log_message().severity, some_severity);
	EXPECT_EQ(handler.log_message().timestamp, some_time);

	mavlink_statustext_t statustext2 {};
	statustext2.severity = some_other_severity;
	strncpy(statustext2.text, some_other_text, sizeof(statustext2.text));

	EXPECT_FALSE(handler.should_publish_previous(statustext2));
	EXPECT_TRUE(handler.should_publish_current(statustext2, some_other_time));
	EXPECT_STREQ(handler.log_message().text, some_other_text);
	EXPECT_EQ(handler.log_message().severity, some_other_severity);
	EXPECT_EQ(handler.log_message().timestamp, some_other_time);
}

TEST(MavlinkStatustextHandler, Multiple)
{
	MavlinkStatustextHandler handler;

	mavlink_statustext_t statustext1 {};
	mavlink_statustext_t statustext2 {};

	statustext1.severity = some_severity;
	statustext2.severity = some_severity;

	statustext1.id = 1;
	statustext2.id = 1;

	statustext1.chunk_seq = 0;
	statustext2.chunk_seq = 1;

	memset(statustext1.text, 'a', 50);
	memset(statustext2.text, 'b', 25);

	// The first message is just stored, we don't have to publish yet.
	EXPECT_FALSE(handler.should_publish_previous(statustext1));
	EXPECT_FALSE(handler.should_publish_current(statustext1, some_time));
	// Now we should be able to publish.
	EXPECT_FALSE(handler.should_publish_previous(statustext2));
	EXPECT_TRUE(handler.should_publish_current(statustext2, some_other_time));

	// Check overall text length.
	EXPECT_EQ(strlen(handler.log_message().text), 75);

	// And a few samples.
	EXPECT_EQ(handler.log_message().text[30], 'a');
	EXPECT_EQ(handler.log_message().text[60], 'b');

	EXPECT_EQ(handler.log_message().severity, some_severity);
	EXPECT_EQ(handler.log_message().timestamp, some_time);
}

TEST(MavlinkStatustextHandler, TooMany)
{
	// If we receive too many, we need to cap it.
	MavlinkStatustextHandler handler;

	mavlink_statustext_t statustext1 {};
	mavlink_statustext_t statustext2 {};
	mavlink_statustext_t statustext3 {};

	statustext1.id = 1;
	statustext2.id = 1;
	statustext3.id = 1;

	statustext1.chunk_seq = 0;
	statustext2.chunk_seq = 1;
	statustext3.chunk_seq = 2;

	memset(statustext1.text, 'a', 50);
	memset(statustext2.text, 'b', 50);
	memset(statustext3.text, 'c', 49);

	// The first messages are just stored, we don't have to publish yet.
	EXPECT_FALSE(handler.should_publish_previous(statustext1));
	EXPECT_FALSE(handler.should_publish_current(statustext1, some_time));
	EXPECT_FALSE(handler.should_publish_previous(statustext2));
	EXPECT_FALSE(handler.should_publish_current(statustext2, some_time + 1));
	EXPECT_FALSE(handler.should_publish_previous(statustext3));
	EXPECT_TRUE(handler.should_publish_current(statustext3, some_time + 2));

	EXPECT_EQ(strlen(handler.log_message().text), sizeof(log_message_s::text) - 1);
}

TEST(MavlinkStatustextHandler, LastMissing)
{
	// Here we fail to send the last multi-chunk but we still want to
	// publish the incomplete message.

	MavlinkStatustextHandler handler;

	mavlink_statustext_t statustext1 {};
	statustext1.id = 1;
	statustext1.chunk_seq = 0;

	memset(statustext1.text, 'a', 50);

	// The first message is just stored, we don't have to publish yet.
	EXPECT_FALSE(handler.should_publish_previous(statustext1));
	EXPECT_FALSE(handler.should_publish_current(statustext1, some_time));

	// Now we send a single and we expect the previous one to be published.
	mavlink_statustext_t statustext2 {};
	memset(statustext2.text, 'b', 10);
	statustext2.id = 0;

	// We expect 50 a and then a missing bracket.
	EXPECT_TRUE(handler.should_publish_previous(statustext2));
	EXPECT_EQ(strlen(handler.log_message().text), 50 + 15);
	EXPECT_EQ(handler.log_message().text[25], 'a');

	EXPECT_TRUE(handler.should_publish_previous(statustext2));
	EXPECT_TRUE(handler.should_publish_current(statustext2, some_other_time));
	// And we expect the single message to get through as well.
	EXPECT_EQ(strlen(handler.log_message().text), 10);
	EXPECT_EQ(handler.log_message().text[5], 'b');
}

TEST(MavlinkStatustextHandler, FirstMissing)
{
	// Here we fail to send the first multi-chunk but we still want to
	// publish the incomplete message.

	MavlinkStatustextHandler handler;

	mavlink_statustext_t statustext2 {};
	statustext2.id = 1;
	statustext2.chunk_seq = 1;

	// By chosing 35 we might exactly trigger an overflow if we don't pay attention.
	memset(statustext2.text, 'b', 35);

	// The first message is just stored, we don't have to publish yet.
	EXPECT_FALSE(handler.should_publish_previous(statustext2));
	EXPECT_TRUE(handler.should_publish_current(statustext2, some_time));

	// We expect a missing bracket and our 10 b.
	EXPECT_EQ(strlen(handler.log_message().text), 15 + 35);
	EXPECT_EQ(handler.log_message().text[20], 'b');
}

TEST(MavlinkStatustextHandler, MiddleMissing)
{
	// This time one message in the middle goes missing.
	MavlinkStatustextHandler handler;

	mavlink_statustext_t statustext1 {};
	mavlink_statustext_t statustext3 {};

	statustext1.id = 1;
	statustext3.id = 1;

	statustext1.chunk_seq = 0;
	statustext3.chunk_seq = 2;

	memset(statustext1.text, 'a', 50);
	memset(statustext3.text, 'c', 25);

	// The first messages are just stored, we don't have to publish yet.
	EXPECT_FALSE(handler.should_publish_previous(statustext1));
	EXPECT_FALSE(handler.should_publish_current(statustext1, some_time));
	EXPECT_FALSE(handler.should_publish_previous(statustext3));
	EXPECT_TRUE(handler.should_publish_current(statustext3, some_time + 2));

	// The two texts plus the missing bracket.
	EXPECT_EQ(strlen(handler.log_message().text), 50 + 25 + 15);
	EXPECT_EQ(handler.log_message().text[20], 'a');
	EXPECT_EQ(handler.log_message().text[70], 'c');
}

TEST(MavlinkStatustextHandler, NoGarbageAfterZeroTermination)
{
	// It would be nicer not to publish garbage after the zero termination
	// from previous publications but to zero it out nicely.
	// Otherwise, someone looking at the raw bytes might get confused.

	MavlinkStatustextHandler handler;

	const auto long_text = "Some rather long text, ramble ramble";
	const auto short_text = "Short short";

	mavlink_statustext_t statustext1 {};
	statustext1.severity = some_severity;
	strncpy(statustext1.text, long_text, sizeof(statustext1.text));

	EXPECT_FALSE(handler.should_publish_previous(statustext1));
	EXPECT_TRUE(handler.should_publish_current(statustext1, some_time));
	EXPECT_STREQ(handler.log_message().text, long_text);

	for (unsigned i = strlen(handler.log_message().text); i < sizeof(log_message_s::text); ++i) {
		EXPECT_EQ(handler.log_message().text[i], '\0');
	}

	mavlink_statustext_t statustext2 {};
	statustext2.severity = some_other_severity;
	strncpy(statustext2.text, short_text, sizeof(statustext2.text));

	EXPECT_FALSE(handler.should_publish_previous(statustext2));
	EXPECT_TRUE(handler.should_publish_current(statustext2, some_other_time));
	EXPECT_STREQ(handler.log_message().text, short_text);

	for (unsigned i = strlen(handler.log_message().text); i < sizeof(log_message_s::text); ++i) {
		EXPECT_EQ(handler.log_message().text[i], '\0');
	}
}