using System.Text.Json;

namespace MAF1.Agents;

/// <summary>
/// 一次 Agent 执行的统一结果。网页编排器和进程外插件都用这套字段，方便画布把输出接到下一节点。
/// Message 是给日志看的原文；Outputs 才是下游节点真正读取的端口数据。
/// </summary>
public sealed class AgentStepResult
{
    public string Message { get; init; } = "";
    public Dictionary<string, object?> Inputs { get; init; } = new(StringComparer.OrdinalIgnoreCase);
    public Dictionary<string, object?> Outputs { get; init; } = new(StringComparer.OrdinalIgnoreCase);
}

/// <summary>
/// 从图 JSON / 插件 stdin 读入参。值可能是 string、数组，也可能是 System.Text.Json 反序列化后的 JsonElement。
/// </summary>
public static class AgentInputs
{
    /// <summary>按端口名读一个字符串；没有该键则返回 null。</summary>
    public static string? ReadString(IReadOnlyDictionary<string, object?> inputs, string key)
    {
        if (!inputs.TryGetValue(key, out object? value) || value is null)
        {
            return null;
        }

        if (value is JsonElement el)
        {
            return el.ValueKind == JsonValueKind.String ? el.GetString() : el.ToString();
        }

        return value.ToString();
    }

    /// <summary>读城市列表：支持 JSON 数组、["a","b"] 风格，或用顿号/逗号分隔的一串文字。</summary>
    public static List<string> ReadStringList(IReadOnlyDictionary<string, object?> inputs, string key)
    {
        if (!inputs.TryGetValue(key, out object? value) || value is null)
        {
            return [];
        }

        if (value is JsonElement el)
        {
            if (el.ValueKind == JsonValueKind.Array)
            {
                return el.EnumerateArray()
                    .Select(item => item.ValueKind == JsonValueKind.String ? item.GetString() : item.ToString())
                    .Where(s => !string.IsNullOrWhiteSpace(s))
                    .Select(s => s!.Trim())
                    .ToList();
            }

            if (el.ValueKind == JsonValueKind.String)
            {
                return Split(el.GetString());
            }
        }

        if (value is IEnumerable<string> typed)
        {
            return typed.Where(v => !string.IsNullOrWhiteSpace(v)).Select(v => v.Trim()).ToList();
        }

        if (value is IEnumerable<object> objects)
        {
            return objects.Select(o => o?.ToString())
                .Where(s => !string.IsNullOrWhiteSpace(s))
                .Select(s => s!.Trim())
                .ToList();
        }

        return Split(value.ToString());
    }

    private static List<string> Split(string? text)
    {
        if (string.IsNullOrWhiteSpace(text))
        {
            return [];
        }

        return text.Split(['、', ',', ';', '\n'], StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries)
            .ToList();
    }
}