diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..70f3938
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,135 @@
+## Shamelessly stolen from https://gist.github.com/takekazuomi/10955889
+
+## Ignore Visual Studio temporary files, build results, and
+## files generated by popular Visual Studio add-ons.
+
+# User-specific files
+*.suo
+*.user
+*.sln.docstates
+
+# Build results
+
+[Dd]ebug/
+[Rr]elease/
+x64/
+[Bb]in/
+[Oo]bj/
+
+# MSTest test Results
+[Tt]est[Rr]esult*/
+[Bb]uild[Ll]og.*
+
+*_i.c
+*_p.c
+*_i.h
+*.ilk
+*.meta
+*.obj
+*.pch
+*.pdb
+*.pgc
+*.pgd
+*.rsp
+*.sbr
+*.tlb
+*.tli
+*.tlh
+*.tmp
+*.tmp_proj
+*.log
+*.vspscc
+*.vssscc
+.builds
+*.pidb
+*.log
+*.svclog
+*.scc
+
+# Visual C++ cache files
+ipch/
+*.aps
+*.ncb
+*.opensdf
+*.sdf
+*.cachefile
+
+# Visual Studio profiler
+*.psess
+*.vsp
+*.vspx
+
+# Guidance Automation Toolkit
+*.gpState
+
+# ReSharper is a .NET coding add-in
+_ReSharper*/
+*.[Rr]e[Ss]harper
+*.DotSettings.user
+
+# Click-Once directory
+publish/
+
+# Publish Web Output
+*.Publish.xml
+*.pubxml
+*.azurePubxml
+
+# NuGet Packages Directory
+## TODO: If you have NuGet Package Restore enabled, uncomment the next line
+packages/
+## TODO: If the tool you use requires repositories.config, also uncomment the next line
+!packages/repositories.config
+
+# Windows Azure Build Output
+csx/
+*.build.csdef
+
+# Windows Store app package directory
+AppPackages/
+
+# Others
+sql/
+*.Cache
+ClientBin/
+[Ss]tyle[Cc]op.*
+![Ss]tyle[Cc]op.targets
+~$*
+*~
+*.dbmdl
+*.[Pp]ublish.xml
+
+*.publishsettings
+
+# RIA/Silverlight projects
+Generated_Code/
+
+# Backup & report files from converting an old project file to a newer
+# Visual Studio version. Backup files are not needed, because we have git ;-)
+_UpgradeReport_Files/
+Backup*/
+UpgradeLog*.XML
+UpgradeLog*.htm
+
+# SQL Server files
+App_Data/*.mdf
+App_Data/*.ldf
+
+# =========================
+# Windows detritus
+# =========================
+
+# Windows image file caches
+Thumbs.db
+ehthumbs.db
+
+# Folder config file
+Desktop.ini
+
+# Recycle Bin used on file shares
+$RECYCLE.BIN/
+
+# Mac desktop service store files
+.DS_Store
+
+_NCrunch*
\ No newline at end of file
diff --git a/README.md b/README.md
index df21dc8..a14bb6f 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,17 @@
+# Petar Parushev 
+
+## Notes and thoughts
+Took me a while longer that I had hoped it would but I am generally pleased with how this task turned out. My C# is super rusty and I also forgot all of VS's shortcuts.
+I developed it mostly using TDD and I have added unit tests for more than the controller classes. I do not have proper endpoint tests - I would add a in-memory API that I call using actual HTTP calls to check routes, parameters, validation and etc.
+I am missing validation in controllers. I should add attributres on the query parameters to make sure that they are not null and that the start date should be less than the end date
+
+## API performance and scale
+I converted the API to asynchronos execution in one of the last commits which should make it easier on the threadpool. 
+The solution is stateless so it can scale indefinetely behind a load balancer. 
+I am making a call to USGS on every request which can be improved by setting up some sort of cache-ing. Surely there is an earthquake every second but most of them are insignificant and the use case of this system means that we don't need that fresh of data.
+
+
+
 # Earthquake Challenge
 
 ## Was that an Earthquake?
diff --git a/topggcsharpchallenge/topggchallengetest/Controllers/EarthquakeControllerTest.cs b/topggcsharpchallenge/topggchallengetest/Controllers/EarthquakeControllerTest.cs
new file mode 100644
index 0000000..2e998d7
--- /dev/null
+++ b/topggcsharpchallenge/topggchallengetest/Controllers/EarthquakeControllerTest.cs
@@ -0,0 +1,121 @@
+using System;
+using System.Collections.Generic;
+using System.Threading.Tasks;
+
+using Microsoft.AspNetCore.Mvc;
+using Moq;
+using NUnit.Framework;
+
+using topggcsharpchallenge.Controllers;
+using topggcsharpchallenge.Models;
+using topggcsharpchallenge.Services;
+
+namespace topggcsharpchallengetest.Controllers
+{
+    [TestFixture]
+    public class EarthquakeControllerTest
+    {
+        private readonly Mock<IEarthquakeService> earthquakeServiceMock = new Mock<IEarthquakeService>();
+
+        private EarthquakeController sut;
+
+        [SetUp]
+        public void SetUp()
+        {
+            sut = new EarthquakeController(earthquakeServiceMock.Object);
+        }
+
+        [Test]
+        public async Task GetShouldBeSuccessfull()
+        {
+            int latitude = 10;
+            int longitude = 20;
+            DateTime startDate = DateTime.MinValue;
+            DateTime endDate = DateTime.Now;
+            IList<EarthquakeResponseModel> mockedData = getEarthquakeResponseModelMockData();
+            earthquakeServiceMock.Setup((x) => x.Get(latitude, longitude, startDate, endDate)).Returns(Task.FromResult(mockedData));
+
+            ActionResult<IEnumerable<EarthquakeResponseModel>> response = await sut.Get(latitude, longitude, startDate, endDate);
+
+            Assert.IsInstanceOf<OkObjectResult>(response.Result);
+            OkObjectResult result = (OkObjectResult) response.Result;
+            Assert.That(result.Value, Is.EqualTo(mockedData));
+            earthquakeServiceMock.Verify((x) => x.Get(latitude, longitude, startDate, endDate), Times.Once);
+        }
+
+
+        [Test]
+        public async Task GetShouldReturn404WhenNoQuakesFound()
+        {
+            int latitude = 10;
+            int longitude = 20;
+            DateTime startDate = DateTime.MinValue;
+            DateTime endDate = DateTime.Now;
+            IList<EarthquakeResponseModel> mockedData = new List<EarthquakeResponseModel>();
+            earthquakeServiceMock.Setup((x) => x.Get(latitude, longitude, startDate, endDate)).Returns(Task.FromResult(mockedData));
+
+            ActionResult<IEnumerable<EarthquakeResponseModel>> response = await sut.Get(latitude, longitude, startDate, endDate);
+
+            Assert.IsInstanceOf<NotFoundResult>(response.Result);
+            earthquakeServiceMock.Verify((x) => x.Get(latitude, longitude, startDate, endDate), Times.Once);
+        }
+
+        private IList<EarthquakeResponseModel> getEarthquakeResponseModelMockData()
+        {
+            return new List<EarthquakeResponseModel>()
+            {
+                new EarthquakeResponseModel()
+                {
+                    Time = DateTime.MinValue,
+                    Latitude = 0.1234,
+                    Longitude = 4.3210,
+                    Depth = 123.456,
+                    Mag = 654.312,
+                    MagType = "md",
+                    Nst = 1,
+                    Gap = 2,
+                    Dmin = 2.34,
+                    Rms = 3.45,
+                    Net = "nc",
+                    Id = "nc73636400",
+                    Updated = DateTime.Now,
+                    Place = "sofia",
+                    Type = "earthquake",
+                    HorizontalError = 0.111,
+                    DepthError = 0.222,
+                    MagError = 0.333,
+                    MagNst = 4,
+                    Status = "automatic",
+                    LocationSource = "nc",
+                    MagSource = "nc"
+                },
+                new EarthquakeResponseModel()
+                {
+                    Time = DateTime.Now,
+                    Latitude = 0.000001,
+                    Longitude = 0.000002,
+                    Depth = 0.000003,
+                    Mag = 0.000004,
+                    MagType = "dm",
+                    Nst = 200,
+                    Gap = 300,
+                    Dmin = 0.000005,
+                    Rms = 0.000006,
+                    Net = "cn",
+                    Id = "cn73636400",
+                    Updated = DateTime.MaxValue,
+                    Place = "nyc",
+                    Type = "earthquake",
+                    HorizontalError = 0.000007,
+                    DepthError = 0.000008,
+                    MagError = 0.000009,
+                    MagNst = 400,
+                    Status = "reviwed",
+                    LocationSource = "ls",
+                    MagSource = "ms"
+                },
+            };
+        }
+
+    }
+}
diff --git a/topggcsharpchallenge/topggchallengetest/Services/EarthquakeServiceTest.cs b/topggcsharpchallenge/topggchallengetest/Services/EarthquakeServiceTest.cs
new file mode 100644
index 0000000..9102f95
--- /dev/null
+++ b/topggcsharpchallenge/topggchallengetest/Services/EarthquakeServiceTest.cs
@@ -0,0 +1,238 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using Moq;
+using NUnit.Framework;
+using topggcsharpchallenge;
+using topggcsharpchallenge.Models;
+using topggcsharpchallenge.Services;
+
+namespace topggcsharpchallengetest.Services
+{
+    [TestFixture]
+    public class EarthquakeServiceTest
+    {
+        private readonly Mock<IUsgsService> usgsServiceMock = new Mock<IUsgsService>();
+
+        private IEarthquakeService sut;
+
+        [SetUp]
+        public void SetUp()
+        {
+            sut = new EarthquakeService(usgsServiceMock.Object);
+        }
+
+        [Test]
+        public async Task GetShouldBeSuccessfull()
+        {
+            int latitude = 0;
+            int longitude = 0;
+            DateTime startDate = DateTime.MinValue;
+            DateTime endDate = DateTime.MaxValue;
+            IList<EarthquakeResponseModel> mockedEarthquakeData = getUsgsServiceGetEarthquakeDataMocks();
+            byte[] csv = createCsv(mockedEarthquakeData);
+            usgsServiceMock.Setup((x) => x.GetEarthquakeData()).Returns(Task.FromResult(csv));
+            IList<EarthquakeResponseModel> expectedEarthquakeData = mockedEarthquakeData.OrderByDescending(x => x.Time).ToList();
+
+            IList<EarthquakeResponseModel> actualEarthquakeData = await sut.Get(latitude, longitude, startDate, endDate);
+
+            Assert.That(actualEarthquakeData, Is.EqualTo(expectedEarthquakeData));
+            IList<DateTime> dates = actualEarthquakeData.Select(x => x.Time).ToList();
+            for (int i = 0; i < dates.Count - 1; i++)
+            {
+                Assert.That(dates[i] >= dates[i + 1]);
+            }
+        }
+
+        [Test]
+        public async Task GetShouldReturnEmptyWhenIntervalBeforeAnyQuakes()
+        {
+            int latitude = 10;
+            int longitude = 20;
+            DateTime startDate = new DateTime(1111, 1, 1);
+            DateTime endDate = new DateTime(1112, 1, 1);
+            IList<EarthquakeResponseModel> expectedEarthquakeData = getUsgsServiceGetEarthquakeDataMocks();
+            byte[] csv = createCsv(expectedEarthquakeData);
+            usgsServiceMock.Setup((x) => x.GetEarthquakeData()).Returns(Task.FromResult(csv));
+
+            IEnumerable<EarthquakeResponseModel> actualEarthquakeData = await sut.Get(latitude, longitude, startDate, endDate);
+
+            Assert.That(actualEarthquakeData, Is.Empty);
+        }
+
+        [Test]
+        public async Task GetShouldReturnEmptyWhenIntervalAfterAnyQuakes()
+        {
+            int latitude = 10;
+            int longitude = 20;
+            DateTime startDate = new DateTime(2222, 1, 1);
+            DateTime endDate = new DateTime(2223, 1, 1);
+            IList<EarthquakeResponseModel> expectedEarthquakeData = getUsgsServiceGetEarthquakeDataMocks();
+            byte[] csv = createCsv(expectedEarthquakeData);
+            usgsServiceMock.Setup((x) => x.GetEarthquakeData()).Returns(Task.FromResult(csv));
+
+            IList<EarthquakeResponseModel> actualEarthquakeData = await sut .Get(latitude, longitude, startDate, endDate);
+
+            Assert.That(actualEarthquakeData, Is.Empty);
+        }
+
+        [Test]
+        public async Task GetShouldReturnOnlyQuakesWithValidTime()
+        {
+            int latitude = 0;
+            int longitude = 0;
+            DateTime startDate = new DateTime(1995, 1, 1);
+            DateTime endDate = new DateTime(2020, 1, 1);
+            IList<EarthquakeResponseModel> expectedEarthquakeData = getUsgsServiceGetEarthquakeDataMocks();
+            byte[] csv = createCsv(expectedEarthquakeData);
+            usgsServiceMock.Setup((x) => x.GetEarthquakeData()).Returns(Task.FromResult(csv));
+
+            IList<EarthquakeResponseModel> actualEarthquakeData = await sut.Get(latitude, longitude, startDate, endDate);
+
+            Assert.That(actualEarthquakeData.Count, Is.EqualTo(1));
+            Assert.That(actualEarthquakeData[0], Is.EqualTo(expectedEarthquakeData[1]));
+        }
+
+        [Test]
+        public async Task GetShouldReturnNoQuakesWhenThereAreNoneInRange()
+        {
+            int latitude = 90;
+            int longitude = 90;
+            DateTime startDate = DateTime.MinValue;
+            DateTime endDate = DateTime.MaxValue;
+            IList<EarthquakeResponseModel> expectedEarthquakeData = getUsgsServiceGetEarthquakeDataMocks();
+            byte[] csv = createCsv(expectedEarthquakeData);
+            usgsServiceMock.Setup((x) => x.GetEarthquakeData()).Returns(Task.FromResult(csv));
+
+            IList<EarthquakeResponseModel> actualEarthquakeData = await sut.Get(latitude, longitude, startDate, endDate);
+
+            Assert.That(actualEarthquakeData, Is.Empty);
+        }
+
+        [Test]
+        public async Task GetShouldReturnSomeQuakesWhenTheyAreInRange()
+        {
+            int latitude = 10;
+            int longitude = 10;
+            DateTime startDate = DateTime.MinValue;
+            DateTime endDate = DateTime.MaxValue;
+            IList<EarthquakeResponseModel> expectedEarthquakeData = getUsgsServiceGetEarthquakeDataMocks();
+            byte[] csv = createCsv(expectedEarthquakeData);
+            usgsServiceMock.Setup((x) => x.GetEarthquakeData()).Returns(Task.FromResult(csv));
+
+            IList<EarthquakeResponseModel> actualEarthquakeData = await sut.Get(latitude, longitude, startDate, endDate);
+
+            Assert.That(actualEarthquakeData.Count, Is.EqualTo(1));
+            Assert.That(actualEarthquakeData[0], Is.EqualTo(expectedEarthquakeData[1]));
+        }
+
+        [Test]
+        public async Task GetShouldReturnNoMoreThanTheLimitOfResults()
+        {
+            int latitude = 0;
+            int longitude = 0;
+            DateTime startDate = DateTime.MinValue;
+            DateTime endDate = DateTime.MaxValue;
+            IList<EarthquakeResponseModel> expectedEarthquakeData = getUsgsServiceGetEarthquakeDataMocksMany();
+            byte[] csv = createCsv(expectedEarthquakeData);
+            usgsServiceMock.Setup((x) => x.GetEarthquakeData()).Returns(Task.FromResult(csv));
+
+            IList<EarthquakeResponseModel> actualEarthquakeData = await sut.Get(latitude, longitude, startDate, endDate);
+
+            Assert.That(actualEarthquakeData.Count, Is.EqualTo(Constants.EARTHQUAKE_COUNT_LIMIT));
+        }
+
+        private IList<EarthquakeResponseModel> getUsgsServiceGetEarthquakeDataMocks()
+        {
+            return new List<EarthquakeResponseModel>()
+            {
+                new EarthquakeResponseModel()
+                {
+                    Time = new DateTime(1993, 9, 29),
+                    Latitude = 0,
+                    Longitude = 0,
+                    Depth = 123.456,
+                    Mag = 0.00000001,
+                    MagType = "md",
+                    Nst = 1,
+                    Gap = 2,
+                    Dmin = 2.34,
+                    Rms = 3.45,
+                    Net = "nc",
+                    Id = "nc73636400",
+                    Updated = new DateTime(1993, 9, 29),
+                    Place = "sofia",
+                    Type = "earthquake",
+                    HorizontalError = 0.111,
+                    DepthError = 0.222,
+                    MagError = 0.333,
+                    MagNst = 4,
+                    Status = "automatic",
+                    LocationSource = "nc",
+                    MagSource = "nc"
+                },
+                new EarthquakeResponseModel()
+                {
+                    Time = new DateTime(1996, 1, 11),
+                    Latitude = 180,
+                    Longitude = 180,
+                    Depth = 0.000003,
+                    Mag = 20,
+                    MagType = "dm",
+                    Nst = 200,
+                    Gap = 300,
+                    Dmin = 0.000005,
+                    Rms = 0.000006,
+                    Net = "cn",
+                    Id = "cn73636400",
+                    Updated = new DateTime(1996, 1, 11),
+                    Place = "nyc",
+                    Type = "earthquake",
+                    HorizontalError = 0.000007,
+                    DepthError = 0.000008,
+                    MagError = 0.000009,
+                    MagNst = 400,
+                    Status = "reviewed",
+                    LocationSource = "ls",
+                    MagSource = "ms"
+                },
+            };
+        }
+
+        private IList<EarthquakeResponseModel> getUsgsServiceGetEarthquakeDataMocksMany()
+        {
+            return new List<EarthquakeResponseModel>()
+            {
+                new EarthquakeResponseModel(),
+                new EarthquakeResponseModel(),
+                new EarthquakeResponseModel(),
+                new EarthquakeResponseModel(),
+                new EarthquakeResponseModel(),
+                new EarthquakeResponseModel(),
+                new EarthquakeResponseModel(),
+                new EarthquakeResponseModel(),
+                new EarthquakeResponseModel(),
+                new EarthquakeResponseModel(),
+                new EarthquakeResponseModel(),
+                new EarthquakeResponseModel(),
+                new EarthquakeResponseModel(),
+            };
+        }
+
+        private byte[] createCsv(IList<EarthquakeResponseModel> quakes)
+        {
+            StringBuilder stringBuilder = new StringBuilder();
+            stringBuilder.Append("time,latitude,longitude,depth,mag,magType,nst,gap,dmin,rms,net,id,updated,place,type,horizontalError,depthError,magError,magNst,status,locationSource,magSource");
+            foreach (EarthquakeResponseModel quake in quakes)
+            {
+                stringBuilder.Append("\n");
+                stringBuilder.Append(quake.ToString());
+            }
+
+
+            return Encoding.ASCII.GetBytes(stringBuilder.ToString());
+        }
+    }
+}
diff --git a/topggcsharpchallenge/topggchallengetest/topggcsharpchallengetest.csproj b/topggcsharpchallenge/topggchallengetest/topggcsharpchallengetest.csproj
new file mode 100644
index 0000000..4f9dfb7
--- /dev/null
+++ b/topggcsharpchallenge/topggchallengetest/topggcsharpchallengetest.csproj
@@ -0,0 +1,21 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>netcoreapp3.1</TargetFramework>
+
+    <IsPackable>false</IsPackable>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.9.4" />
+    <PackageReference Include="Moq" Version="4.16.1" />
+    <PackageReference Include="NUnit" Version="3.13.1" />
+    <PackageReference Include="NUnit3TestAdapter" Version="3.17.0" />
+    <PackageReference Include="coverlet.collector" Version="3.0.2" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\topggcsharpchallenge\topggcsharpchallenge.csproj" />
+  </ItemGroup>
+
+</Project>
diff --git a/topggcsharpchallenge/topggcsharpchallenge.sln b/topggcsharpchallenge/topggcsharpchallenge.sln
new file mode 100644
index 0000000..0d899ac
--- /dev/null
+++ b/topggcsharpchallenge/topggcsharpchallenge.sln
@@ -0,0 +1,31 @@
+
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio Version 16
+VisualStudioVersion = 16.0.31702.278
+MinimumVisualStudioVersion = 10.0.40219.1
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "topggcsharpchallenge", "topggcsharpchallenge\topggcsharpchallenge.csproj", "{EFDE0803-2939-4275-92A9-B2C9355FAE16}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "topggcsharpchallengetest", "topggchallengetest\topggcsharpchallengetest.csproj", "{948C5E86-5E33-410F-8BDA-BC7C666278F0}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Release|Any CPU = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{EFDE0803-2939-4275-92A9-B2C9355FAE16}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{EFDE0803-2939-4275-92A9-B2C9355FAE16}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{EFDE0803-2939-4275-92A9-B2C9355FAE16}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{EFDE0803-2939-4275-92A9-B2C9355FAE16}.Release|Any CPU.Build.0 = Release|Any CPU
+		{948C5E86-5E33-410F-8BDA-BC7C666278F0}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{948C5E86-5E33-410F-8BDA-BC7C666278F0}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{948C5E86-5E33-410F-8BDA-BC7C666278F0}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{948C5E86-5E33-410F-8BDA-BC7C666278F0}.Release|Any CPU.Build.0 = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(SolutionProperties) = preSolution
+		HideSolutionNode = FALSE
+	EndGlobalSection
+	GlobalSection(ExtensibilityGlobals) = postSolution
+		SolutionGuid = {39454A13-FC7F-44EE-A3AE-CEE0FF150ECA}
+	EndGlobalSection
+EndGlobal
diff --git a/topggcsharpchallenge/topggcsharpchallenge/AssemblyInfo.cs b/topggcsharpchallenge/topggcsharpchallenge/AssemblyInfo.cs
new file mode 100644
index 0000000..215d955
--- /dev/null
+++ b/topggcsharpchallenge/topggcsharpchallenge/AssemblyInfo.cs
@@ -0,0 +1,21 @@
+using System.Runtime.CompilerServices;
+using System.Runtime.InteropServices;
+
+// In SDK-style projects such as this one, several assembly attributes that were historically
+// defined in this file are now automatically added during build and populated with
+// values defined in project properties. For details of which attributes are included
+// and how to customise this process see: https://aka.ms/assembly-info-properties
+
+
+// Setting ComVisible to false makes the types in this assembly not visible to COM
+// components.  If you need to access a type in this assembly from COM, set the ComVisible
+// attribute to true on that type.
+
+[assembly: ComVisible(false)]
+
+// The following GUID is for the ID of the typelib if this project is exposed to COM.
+
+[assembly: Guid("edeaad31-e994-4648-ae4f-346454635958")]
+
+[assembly: InternalsVisibleTo("topggcsharpchallengetest")]
+[assembly: InternalsVisibleTo("DynamicProxyGenAssembly2")]
diff --git a/topggcsharpchallenge/topggcsharpchallenge/Constants.cs b/topggcsharpchallenge/topggcsharpchallenge/Constants.cs
new file mode 100644
index 0000000..c318360
--- /dev/null
+++ b/topggcsharpchallenge/topggcsharpchallenge/Constants.cs
@@ -0,0 +1,16 @@
+namespace topggcsharpchallenge
+{
+    public static class Constants
+    {
+        public const int EARTH_RADIUS_MILES = 3959;
+        public const int TRAVEL_DISTANCE_FACTOR = 100;
+
+        // Count could/should be configurable
+        public const int EARTHQUAKE_COUNT_LIMIT = 10;
+
+        // Url could/should be configurable
+        public const string USGS_LATEST_REPORT_URL = "https://earthquake.usgs.gov/earthquakes/feed/v1.0/summary/all_month.csv";
+
+        public const string DATE_FORMAT = "yyyy'-'MM'-'dd'T'HH':'mm':'ss'.'fff'Z'";
+    }
+}
diff --git a/topggcsharpchallenge/topggcsharpchallenge/Controllers/EarthquakeController.cs b/topggcsharpchallenge/topggcsharpchallenge/Controllers/EarthquakeController.cs
new file mode 100644
index 0000000..24b9dba
--- /dev/null
+++ b/topggcsharpchallenge/topggcsharpchallenge/Controllers/EarthquakeController.cs
@@ -0,0 +1,41 @@
+using System;
+using System.Collections.Generic;
+using System.Threading.Tasks;
+using Microsoft.AspNetCore.Http;
+using Microsoft.AspNetCore.Mvc;
+
+using topggcsharpchallenge.Models;
+using topggcsharpchallenge.Services;
+
+namespace topggcsharpchallenge.Controllers
+{
+    [ApiController]
+    [Route("earthquakes")]
+    public class EarthquakeController : ControllerBase
+    {
+        private IEarthquakeService earthquakeService;
+
+        public EarthquakeController(IEarthquakeService earthquakeService)
+        {
+            this.earthquakeService = earthquakeService;
+        }
+
+        [HttpGet]
+        [ProducesResponseType(StatusCodes.Status200OK)]
+        [ProducesResponseType(StatusCodes.Status404NotFound)]
+        public async Task<ActionResult<IEnumerable<EarthquakeResponseModel>>> Get(
+            [FromQuery(Name = "lat")] double latitude,
+            [FromQuery(Name = "long")] double longitude,
+            [FromQuery(Name = "start_date")] DateTime startDate,
+            [FromQuery(Name = "end_date")] DateTime endDate)
+        {
+            IList<EarthquakeResponseModel> quakes = await earthquakeService.Get(latitude, longitude, startDate, endDate);
+            if (quakes.Count == 0)
+            {
+                return NotFound();
+            }
+
+            return new OkObjectResult(quakes);
+        }
+    }
+}
diff --git a/topggcsharpchallenge/topggcsharpchallenge/Models/EarthquakeResponseModel.cs b/topggcsharpchallenge/topggcsharpchallenge/Models/EarthquakeResponseModel.cs
new file mode 100644
index 0000000..c5824ce
--- /dev/null
+++ b/topggcsharpchallenge/topggcsharpchallenge/Models/EarthquakeResponseModel.cs
@@ -0,0 +1,123 @@
+using System;
+using System.Collections.Generic;
+
+namespace topggcsharpchallenge.Models
+{
+    public class EarthquakeResponseModel
+    {
+        public DateTime Time { get; set; }
+        public double Latitude { get; set; }
+        public double Longitude { get; set; }
+        public double Depth { get; set; }
+        public double Mag { get; set; }
+        public string MagType { get; set; }
+        public int Nst { get; set; }
+        public double Gap { get; set; }
+        public double Dmin { get; set; }
+        public double Rms { get; set; }
+        public string Net { get; set; }
+        public string Id { get; set; }
+        public DateTime Updated { get; set; }
+        public string Place { get; set; }
+        public string Type { get; set; }
+        public double HorizontalError { get; set; }
+        public double DepthError { get; set; }
+        public double MagError { get; set; }
+        public int MagNst { get; set; }
+        public string Status { get; set; }
+        public string LocationSource { get; set; }
+        public string MagSource { get; set; }
+
+        public override bool Equals(object obj)
+        {
+            if (!(obj is EarthquakeResponseModel))
+            {
+                return false;
+            }
+
+            EarthquakeResponseModel model = (EarthquakeResponseModel)obj;
+
+            return Time == model.Time &&
+                   Latitude == model.Latitude &&
+                   Longitude == model.Longitude &&
+                   Depth == model.Depth &&
+                   Mag == model.Mag &&
+                   MagType == model.MagType &&
+                   Nst == model.Nst &&
+                   Gap == model.Gap &&
+                   Dmin == model.Dmin &&
+                   Rms == model.Rms &&
+                   Net == model.Net &&
+                   Id == model.Id &&
+                   Updated == model.Updated &&
+                   Place == model.Place &&
+                   Type == model.Type &&
+                   HorizontalError == model.HorizontalError &&
+                   DepthError == model.DepthError &&
+                   MagError == model.MagError &&
+                   MagNst == model.MagNst &&
+                   Status == model.Status &&
+                   LocationSource == model.LocationSource &&
+                   MagSource == model.MagSource;
+        }
+
+        public override int GetHashCode()
+        {
+            HashCode hash = new HashCode();
+            hash.Add(Time);
+            hash.Add(Latitude);
+            hash.Add(Longitude);
+            hash.Add(Depth);
+            hash.Add(Mag);
+            hash.Add(MagType);
+            hash.Add(Nst);
+            hash.Add(Gap);
+            hash.Add(Dmin);
+            hash.Add(Rms);
+            hash.Add(Net);
+            hash.Add(Id);
+            hash.Add(Updated);
+            hash.Add(Place);
+            hash.Add(Type);
+            hash.Add(HorizontalError);
+            hash.Add(DepthError);
+            hash.Add(MagError);
+            hash.Add(MagNst);
+            hash.Add(Status);
+            hash.Add(LocationSource);
+            hash.Add(MagSource);
+            return hash.ToHashCode();
+        }
+
+        public override string ToString()
+        {
+            IList<string> data = new List<string>()
+            {
+                Time.ToUniversalTime().ToString(Constants.DATE_FORMAT),
+                Latitude.ToString(),
+                Longitude.ToString(),
+                Depth.ToString(),
+                Mag.ToString(),
+                MagType,
+                Nst.ToString(),
+                Gap.ToString(),
+                Dmin.ToString(),
+                Rms.ToString(),
+                Net,
+                Id,
+                Updated.ToUniversalTime().ToString(Constants.DATE_FORMAT),
+                Place,
+                Type,
+                HorizontalError.ToString(),
+                DepthError.ToString(),
+                MagError.ToString(),
+                MagNst.ToString(),
+                Status,
+                LocationSource,
+                MagSource
+            };
+
+            return string.Join(',', data);
+        }       
+    }
+}
diff --git a/topggcsharpchallenge/topggcsharpchallenge/Program.cs b/topggcsharpchallenge/topggcsharpchallenge/Program.cs
new file mode 100644
index 0000000..a9d3cc8
--- /dev/null
+++ b/topggcsharpchallenge/topggcsharpchallenge/Program.cs
@@ -0,0 +1,20 @@
+using Microsoft.AspNetCore.Hosting;
+using Microsoft.Extensions.Hosting;
+
+namespace topggcsharpchallenge
+{
+    public class Program
+    {
+        public static void Main(string[] args)
+        {
+            CreateHostBuilder(args).Build().Run();
+        }
+
+        public static IHostBuilder CreateHostBuilder(string[] args) =>
+            Host.CreateDefaultBuilder(args)
+                .ConfigureWebHostDefaults(webBuilder =>
+                {
+                    webBuilder.UseStartup<Startup>();
+                });
+    }
+}
diff --git a/topggcsharpchallenge/topggcsharpchallenge/Properties/launchSettings.json b/topggcsharpchallenge/topggcsharpchallenge/Properties/launchSettings.json
new file mode 100644
index 0000000..58fc29e
--- /dev/null
+++ b/topggcsharpchallenge/topggcsharpchallenge/Properties/launchSettings.json
@@ -0,0 +1,30 @@
+{
+  "$schema": "http://json.schemastore.org/launchsettings.json",
+  "iisSettings": {
+    "windowsAuthentication": false,
+    "anonymousAuthentication": true,
+    "iisExpress": {
+      "applicationUrl": "http://localhost:52785",
+      "sslPort": 44379
+    }
+  },
+  "profiles": {
+    "IIS Express": {
+      "commandName": "IISExpress",
+      "launchBrowser": true,
+      "launchUrl": "",
+      "environmentVariables": {
+        "ASPNETCORE_ENVIRONMENT": "Development"
+      }
+    },
+    "topggcsharpchallenge": {
+      "commandName": "Project",
+      "launchBrowser": true,
+      "launchUrl": "",
+      "applicationUrl": "https://localhost:5001;http://localhost:5000",
+      "environmentVariables": {
+        "ASPNETCORE_ENVIRONMENT": "Development"
+      }
+    }
+  }
+}
diff --git a/topggcsharpchallenge/topggcsharpchallenge/Services/EarthquakeService.cs b/topggcsharpchallenge/topggcsharpchallenge/Services/EarthquakeService.cs
new file mode 100644
index 0000000..e968908
--- /dev/null
+++ b/topggcsharpchallenge/topggcsharpchallenge/Services/EarthquakeService.cs
@@ -0,0 +1,117 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Threading.Tasks;
+
+using Microsoft.VisualBasic.FileIO;
+
+using topggcsharpchallenge.Models;
+
+namespace topggcsharpchallenge.Services
+{
+    public class EarthquakeService : IEarthquakeService
+    {
+        private readonly IUsgsService usgsService;
+
+        public EarthquakeService(IUsgsService usgsService)
+        {
+            this.usgsService = usgsService;
+        }
+
+        async Task<IList<EarthquakeResponseModel>> IEarthquakeService.Get(double latitude, double longitude, DateTime startDate, DateTime endDate)
+        {
+            byte[] earthquakeCsv = await usgsService.GetEarthquakeData();
+
+            IList<EarthquakeResponseModel> earthquakes = ParseEarthquakes(earthquakeCsv);
+
+            return earthquakes
+                .Where(x => startDate <= x.Time && x.Time <= endDate)
+                .Where(x => CalculateDistanceInSphere(x.Latitude, x.Longitude, latitude, longitude) <= x.Mag * Constants.TRAVEL_DISTANCE_FACTOR)
+                .Take(Constants.EARTHQUAKE_COUNT_LIMIT)
+                .OrderByDescending(x => x.Time)
+                .ToList();
+        }
+
+        private double CalculateDistanceInSphere(double lat1, double long1, double lat2, double long2, int sphereRadius = Constants.EARTH_RADIUS_MILES)
+        {
+            int degreesInACircle = 180;
+            double lat1rad = lat1 * Math.PI / degreesInACircle;
+            double lat2rad = lat2 * Math.PI / degreesInACircle;
+            double deltaLat = (lat1 - lat2) * Math.PI / degreesInACircle;
+            double deltaLong = (long1 - long2) * Math.PI / degreesInACircle;
+
+            double a = Math.Pow(Math.Sin(deltaLat / 2), 2) + Math.Pow(Math.Sin(deltaLong / 2), 2) * Math.Cos(lat1rad) * Math.Cos(lat2rad);
+            double c = 2 * Math.Asin(Math.Sqrt(a));
+            return sphereRadius * c;
+        }
+
+        private IList<EarthquakeResponseModel> ParseEarthquakes(byte[] csv)
+        {
+            IList<EarthquakeResponseModel> result = new List<EarthquakeResponseModel>();
+            using (TextFieldParser parser = new TextFieldParser(new MemoryStream(csv)))
+            {
+                parser.TextFieldType = FieldType.Delimited;
+                parser.SetDelimiters(",");
+                bool headerSkipped = false;
+                while (!parser.EndOfData)
+                {
+                    string[] fields = parser.ReadFields();
+                    if (!headerSkipped)
+                    {
+                        headerSkipped = true;
+                        continue;
+                    }
+
+                    result.Add(ParseEarthquake(fields));
+                }
+            }
+
+            return result;
+        }
+
+        private EarthquakeResponseModel ParseEarthquake(string[] fields)
+        {
+            return new EarthquakeResponseModel()
+            {
+                Time = parseToDateTimeOrDefault(fields[0]),
+                Latitude = parseToDoubleOrDefault(fields[1]),
+                Longitude = parseToDoubleOrDefault(fields[2]),
+                Depth = parseToDoubleOrDefault(fields[3]),
+                Mag = parseToDoubleOrDefault(fields[4]),
+                MagType = fields[5],
+                Nst = parseToIntegerOrDefault(fields[6]),
+                Gap = parseToDoubleOrDefault(fields[7]),
+                Dmin = parseToDoubleOrDefault(fields[8]),
+                Rms = parseToDoubleOrDefault(fields[9]),
+                Net = fields[10],
+                Id = fields[11],
+                Updated = parseToDateTimeOrDefault(fields[12]),
+                Place = fields[13],
+                Type = fields[14],
+                HorizontalError = parseToDoubleOrDefault(fields[15]),
+                DepthError = parseToDoubleOrDefault(fields[16]),
+                MagError = parseToDoubleOrDefault(fields[17]),
+                MagNst = parseToIntegerOrDefault(fields[18]),
+                Status = fields[19],
+                LocationSource = fields[20],
+                MagSource = fields[21]
+            };
+        }
+
+        private double parseToDoubleOrDefault(string i)
+        {
+            return i != string.Empty ? double.Parse(i) : 0;
+        }
+
+        private int parseToIntegerOrDefault(string i)
+        {
+            return i != string.Empty ? int.Parse(i) : 0;
+        }
+
+        private DateTime parseToDateTimeOrDefault(string date)
+        {
+            return date != string.Empty ? DateTime.Parse(date) : new DateTime();
+        }
+    }
+}
diff --git a/topggcsharpchallenge/topggcsharpchallenge/Services/IEarthquakeService.cs b/topggcsharpchallenge/topggcsharpchallenge/Services/IEarthquakeService.cs
new file mode 100644
index 0000000..bf5e233
--- /dev/null
+++ b/topggcsharpchallenge/topggcsharpchallenge/Services/IEarthquakeService.cs
@@ -0,0 +1,13 @@
+using System;
+using System.Collections.Generic;
+using System.Threading.Tasks;
+
+using topggcsharpchallenge.Models;
+
+namespace topggcsharpchallenge.Services
+{
+    public interface IEarthquakeService
+    {
+        Task<IList<EarthquakeResponseModel>> Get(double latitude, double longitude, DateTime startDate, DateTime endDate);
+    }
+}
diff --git a/topggcsharpchallenge/topggcsharpchallenge/Services/IUsgsService.cs b/topggcsharpchallenge/topggcsharpchallenge/Services/IUsgsService.cs
new file mode 100644
index 0000000..71b700f
--- /dev/null
+++ b/topggcsharpchallenge/topggcsharpchallenge/Services/IUsgsService.cs
@@ -0,0 +1,9 @@
+using System.Threading.Tasks;
+
+namespace topggcsharpchallenge.Services
+{
+    public interface IUsgsService
+    {
+        Task<byte[]> GetEarthquakeData();
+    }
+}
diff --git a/topggcsharpchallenge/topggcsharpchallenge/Services/UsgsService.cs b/topggcsharpchallenge/topggcsharpchallenge/Services/UsgsService.cs
new file mode 100644
index 0000000..f6eadeb
--- /dev/null
+++ b/topggcsharpchallenge/topggcsharpchallenge/Services/UsgsService.cs
@@ -0,0 +1,18 @@
+using System.Net;
+using System.Threading.Tasks;
+
+namespace topggcsharpchallenge.Services
+{
+    public class UsgsService : IUsgsService
+    {
+        public async Task<byte[]> GetEarthquakeData()
+        {
+            string latestReportUrl = Constants.USGS_LATEST_REPORT_URL;
+
+            using (var client = new WebClient())
+            {
+                return await client.DownloadDataTaskAsync(new System.Uri(latestReportUrl));
+            }
+        }
+    }
+}
diff --git a/topggcsharpchallenge/topggcsharpchallenge/Startup.cs b/topggcsharpchallenge/topggcsharpchallenge/Startup.cs
new file mode 100644
index 0000000..98f9680
--- /dev/null
+++ b/topggcsharpchallenge/topggcsharpchallenge/Startup.cs
@@ -0,0 +1,76 @@
+using System;
+
+using Microsoft.AspNetCore.Builder;
+using Microsoft.AspNetCore.Hosting;
+using Microsoft.Extensions.Configuration;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Hosting;
+using Microsoft.OpenApi.Models;
+using topggcsharpchallenge.Services;
+
+namespace topggcsharpchallenge
+{
+    public class Startup
+    {
+        public Startup(IConfiguration configuration)
+        {
+            Configuration = configuration;
+        }
+
+        public IConfiguration Configuration { get; }
+
+        // This method gets called by the runtime. Use this method to add services to the container.
+        public void ConfigureServices(IServiceCollection services)
+        {
+            services.AddControllers();
+
+            services.AddScoped<IEarthquakeService, EarthquakeService>();
+            services.AddScoped<IUsgsService, UsgsService>();
+
+            services.AddSwaggerGen(c =>
+            {
+                c.SwaggerDoc("v1", new OpenApiInfo
+                {
+                    Title = "Earthquake API",
+                    Version = "v1",
+                    Description = "Provides information on earthquakes.",
+                    Contact = new OpenApiContact
+                    {
+                        Name = "Petar Parushev",
+                        Email = "petergparushev@gmail.com",
+                        Url = new Uri("https://top.gg/"),
+                    },
+                });
+            });
+        }
+
+        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
+        public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
+        {
+            if (env.IsDevelopment())
+            {
+                app.UseDeveloperExceptionPage();
+            }
+
+            app.UseSwagger();
+
+            app.UseSwaggerUI(c =>
+            {
+                c.SwaggerEndpoint("/swagger/v1/swagger.json", "Earthquake API V1");
+
+                c.RoutePrefix = string.Empty;
+            });
+
+            app.UseHttpsRedirection();
+
+            app.UseRouting();
+
+            app.UseAuthorization();
+
+            app.UseEndpoints(endpoints =>
+            {
+                endpoints.MapControllers();
+            });
+        }
+    }
+}
diff --git a/topggcsharpchallenge/topggcsharpchallenge/appsettings.Development.json b/topggcsharpchallenge/topggcsharpchallenge/appsettings.Development.json
new file mode 100644
index 0000000..8983e0f
--- /dev/null
+++ b/topggcsharpchallenge/topggcsharpchallenge/appsettings.Development.json
@@ -0,0 +1,9 @@
+{
+  "Logging": {
+    "LogLevel": {
+      "Default": "Information",
+      "Microsoft": "Warning",
+      "Microsoft.Hosting.Lifetime": "Information"
+    }
+  }
+}
diff --git a/topggcsharpchallenge/topggcsharpchallenge/appsettings.json b/topggcsharpchallenge/topggcsharpchallenge/appsettings.json
new file mode 100644
index 0000000..d9d9a9b
--- /dev/null
+++ b/topggcsharpchallenge/topggcsharpchallenge/appsettings.json
@@ -0,0 +1,10 @@
+{
+  "Logging": {
+    "LogLevel": {
+      "Default": "Information",
+      "Microsoft": "Warning",
+      "Microsoft.Hosting.Lifetime": "Information"
+    }
+  },
+  "AllowedHosts": "*"
+}
diff --git a/topggcsharpchallenge/topggcsharpchallenge/topggcsharpchallenge.csproj b/topggcsharpchallenge/topggcsharpchallenge/topggcsharpchallenge.csproj
new file mode 100644
index 0000000..90e0820
--- /dev/null
+++ b/topggcsharpchallenge/topggcsharpchallenge/topggcsharpchallenge.csproj
@@ -0,0 +1,11 @@
+<Project Sdk="Microsoft.NET.Sdk.Web">
+
+  <PropertyGroup>
+    <TargetFramework>netcoreapp3.1</TargetFramework>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Swashbuckle.AspNetCore" Version="6.2.3" />
+  </ItemGroup>
+
+</Project>