// This file is auto-generated by alef — DO NOT EDIT.
// alef:hash:4e15143f4af1ae8bafbdb1506ef057da924484c66a19483966333558ad437e75
// To regenerate: alef generate
// To verify freshness: alef verify --exit-code
// Issues & docs: https://github.com/kreuzberg-dev/alef
#nullable enable

using System;
using System.Collections.Generic;
using System.Text.Json;
using System.Text.Json.Serialization;

namespace Kreuzberg;

/// <summary>
/// Configuration for an LLM provider/model via liter-llm.
///
/// Each feature (VLM OCR, VLM embeddings, structured extraction) carries
/// its own `LlmConfig`, allowing different providers per feature.
/// </summary>
public sealed record LlmConfig
{
    /// <summary>
    /// Provider/model string using liter-llm routing format.
    ///
    /// Examples: `"openai/gpt-4o"`, `"anthropic/claude-sonnet-4-20250514"`,
    /// `"groq/llama-3.1-70b-versatile"`.
    /// </summary>
    [JsonPropertyName("model")]
    public string Model { get; init; } = "";

    /// <summary>
    /// API key for the provider. When `None`, liter-llm falls back to
    /// the provider's standard environment variable (e.g., `OPENAI_API_KEY`).
    /// </summary>
    [JsonPropertyName("api_key")]
    public string? ApiKey { get; init; } = null;

    /// <summary>
    /// Custom base URL override for the provider endpoint.
    /// </summary>
    [JsonPropertyName("base_url")]
    public string? BaseUrl { get; init; } = null;

    /// <summary>
    /// Request timeout in seconds (default: 60).
    /// </summary>
    [JsonPropertyName("timeout_secs")]
    public ulong? TimeoutSecs { get; init; } = null;

    /// <summary>
    /// Maximum retry attempts (default: 3).
    /// </summary>
    [JsonPropertyName("max_retries")]
    public uint? MaxRetries { get; init; } = null;

    /// <summary>
    /// Sampling temperature for generation tasks.
    /// </summary>
    [JsonPropertyName("temperature")]
    public double? Temperature { get; init; } = null;

    /// <summary>
    /// Maximum tokens to generate.
    /// </summary>
    [JsonPropertyName("max_tokens")]
    public ulong? MaxTokens { get; init; } = null;


    /// <summary>
    /// Parse a <see cref="LlmConfig"/> from a JSON string.
    /// </summary>
    /// <exception cref="KreuzbergException">When the JSON cannot be deserialised.</exception>
    public static LlmConfig FromJson(string json)
    {
        try
        {
            return JsonSerializer.Deserialize<LlmConfig>(json, JsonOptions)
                ?? throw new KreuzbergException($"Failed to parse LlmConfig from JSON: deserializer returned null");
        }
        catch (KreuzbergException)
        {
            throw;
        }
        catch (Exception e)
        {
            throw new KreuzbergException($"Failed to parse LlmConfig from JSON: {e.Message}", e);
        }
    }

    private static readonly JsonSerializerOptions JsonOptions = new()
    {
        DefaultIgnoreCondition = JsonIgnoreCondition.WhenWritingDefault,
        Converters = { new JsonStringEnumConverter(JsonNamingPolicy.SnakeCaseLower) },
    };

    /// <summary>Options for serializing config/input objects to FFI. Strips nulls
    /// (nullable C# fields default to null and would override required Rust fields with
    /// non-deserialisable nulls) but preserves explicit false/0 so caller intent is kept.</summary>
    private static readonly JsonSerializerOptions JsonSerializationOptions = new()
    {
        DefaultIgnoreCondition = JsonIgnoreCondition.WhenWritingNull,
        Converters = { new JsonStringEnumConverter(JsonNamingPolicy.SnakeCaseLower) },
    };
}
