using System.Text.Json;
using System.Text.Json.Serialization;

namespace Agent.Core.Runtime;

/// <summary>
/// LLM-generated plan parsed from structured output.
/// Each planned task contains a description, dependency references (by index),
/// token budget class, PERT estimates, and the requires_external_effect attribute.
/// </summary>
public sealed class PlanResult
{
    [JsonPropertyName("tasks")]
    public List<PlannedTask> Tasks { get; init; } = [];
}

public sealed class PlannedTask
{
    [JsonPropertyName("description")]
    public string Description { get; init; } = string.Empty;

    [JsonPropertyName("dependencies")]
    public List<int> Dependencies { get; init; } = [];

    [JsonPropertyName("budget_class")]
    public string BudgetClass { get; init; } = "4K";

    [JsonPropertyName("optimistic_tokens")]
    public long OptimisticTokens { get; init; }

    [JsonPropertyName("most_likely_tokens")]
    public long MostLikelyTokens { get; init; }

    [JsonPropertyName("pessimistic_tokens")]
    public long PessimisticTokens { get; init; }

    [JsonPropertyName("requires_external_effect")]
    public bool RequiresExternalEffect { get; init; }

    [JsonPropertyName("required_effect_tools")]
    public List<string> RequiredEffectTools { get; init; } = [];
}

/// <summary>
/// JSON Schema for Ollama structured output during Planning.
/// </summary>
public static class PlanSchema
{
    public static string Json => """{"type":"object","properties":{"tasks":{"type":"array","items":{"type":"object","properties":{"description":{"type":"string"},"dependencies":{"type":"array","items":{"type":"integer"}},"budget_class":{"type":"string","enum":["1K","2K","4K","8K","16K","32K","64K","128K"]},"optimistic_tokens":{"type":"integer","minimum":1},"most_likely_tokens":{"type":"integer","minimum":1},"pessimistic_tokens":{"type":"integer","minimum":1},"requires_external_effect":{"type":"boolean"},"required_effect_tools":{"type":"array","items":{"type":"string","enum":["file_edit","process_run","dir"]}}},"required":["description","dependencies","budget_class","optimistic_tokens","most_likely_tokens","pessimistic_tokens","requires_external_effect","required_effect_tools"]}}},"required":["tasks"]}""";

    private static readonly JsonElement _element = JsonDocument.Parse(Json).RootElement.Clone();

    public static JsonElement Element => _element;
}