using System;
using System.IO;
using System.Collections.Generic;
using System.Threading.Tasks;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Text;
using System.Text.Json.Nodes;

var origin = (Environment.GetEnvironmentVariable("STASHBAY_ORIGIN") ?? "https://stashbay.net").TrimEnd('/');
var key = Environment.GetEnvironmentVariable("STASHBAY_API_KEY") ?? throw new Exception("Set STASHBAY_API_KEY");
if (args.Length == 0) throw new Exception("Pass the file path as an argument");
using var client = new HttpClient(new HttpClientHandler { AllowAutoRedirect = false }) { Timeout = TimeSpan.FromMinutes(5) };

async Task<JsonNode> Api(string route, object body)
{
    using var request = new HttpRequestMessage(HttpMethod.Post, origin + "/api/v1" + route);
    request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", key);
    request.Content = new StringContent(System.Text.Json.JsonSerializer.Serialize(body), Encoding.UTF8, "application/json");
    using var response = await client.SendAsync(request);
    var text = await response.Content.ReadAsStringAsync();
    if (!response.IsSuccessStatusCode) throw new Exception($"HTTP {(int)response.StatusCode}: {text}");
    return JsonNode.Parse(text)!;
}

await using var file = File.OpenRead(args[0]);
var size = file.Length;
var plan = await Api("/uploads/init", new { filename = Path.GetFileName(args[0]), sizeBytes = size });
var fileId = plan["fileId"]!.GetValue<string>();
Console.Error.WriteLine($"Upload ID: {fileId}");
var partSize = plan["partSize"]!.GetValue<int>();
if (partSize < 1 || partSize > 64 * 1024 * 1024) throw new Exception("Unexpected part size");
var single = plan["single"]!.GetValue<bool>();
var strategy = plan["strategy"]!.GetValue<string>();
var parts = new List<object>();
for (var number = 1; number <= plan["partCount"]!.GetValue<int>(); number++)
{
    var bytes = new byte[(int)Math.Min(partSize, size - (long)(number - 1) * partSize)];
    await file.ReadExactlyAsync(bytes);
    var address = single ? plan["uploadUrl"]!.GetValue<string>() :
        (await Api("/uploads/parts", new { fileId, from = number, count = 1 }))["parts"]![0]!["url"]!.GetValue<string>();
    var url = new Uri(new Uri(origin), address);
    using var request = new HttpRequestMessage(HttpMethod.Put, url);
    if (strategy == "proxy" && url.GetLeftPart(UriPartial.Authority) == origin)
        request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", key);
    else if (strategy != "presigned" || url.Scheme != "https")
        throw new Exception("Unexpected upload URL or strategy");
    if (single && strategy == "presigned") request.Headers.TryAddWithoutValidation("If-None-Match", "*");
    request.Content = new ByteArrayContent(bytes);
    using var response = await client.SendAsync(request);
    var text = await response.Content.ReadAsStringAsync();
    if (!response.IsSuccessStatusCode) throw new Exception($"PUT {(int)response.StatusCode}: {text}");
    if (!single)
    {
        var etag = strategy == "proxy" ? JsonNode.Parse(text)?["etag"]?.GetValue<string>() : response.Headers.ETag?.Tag;
        if (string.IsNullOrEmpty(etag)) throw new Exception("Missing part ETag");
        parts.Add(new { partNumber = number, etag = etag.Trim('"') });
    }
}
var result = await Api("/uploads/complete", new { fileId, parts });
Console.WriteLine(result["shareUrl"]?.GetValue<string>() ?? result.ToJsonString());