using System.Text.Json;
using ChatAgent.Api.Plugins;
using ChatAgent.Shared.Models;

namespace ChatAgent.Api.Tests;

public class ExtractionPluginTests
{
    private readonly ExtractionPlugin _plugin = new();

    [Fact]
    public void ValidateExtractedFields_AllRequiredPresent_ReturnsValid()
    {
        var fields = new ExtractedFields
        {
            Client = "Acme Corp",
            Project = "Phase 2",
            Hours = 3,
            Rate = 150,
            Currency = "USD",
            Date = "2026-04-01"
        };

        var resultJson = _plugin.ValidateExtractedFields(JsonSerializer.Serialize(fields));
        var result = JsonSerializer.Deserialize<ValidationResult>(resultJson);

        Assert.NotNull(result);
        Assert.True(result.IsValid);
        Assert.Empty(result.Errors);
    }

    [Fact]
    public void ValidateExtractedFields_MissingRequired_ReturnsErrors()
    {
        // Missing Client and Hours
        var fields = new ExtractedFields
        {
            Project = "Phase 2",
            Rate = 150,
            Currency = "USD",
            Date = "2026-04-01"
        };

        var resultJson = _plugin.ValidateExtractedFields(JsonSerializer.Serialize(fields));
        var result = JsonSerializer.Deserialize<ValidationResult>(resultJson);

        Assert.NotNull(result);
        Assert.False(result.IsValid);
        Assert.Contains(result.Errors, e => e.Contains("Client"));
        Assert.Contains(result.Errors, e => e.Contains("Hours"));
    }

    [Fact]
    public void ValidateExtractedFields_InvalidJson_ReturnsError()
    {
        var resultJson = _plugin.ValidateExtractedFields("not valid json");
        var result = JsonSerializer.Deserialize<ValidationResult>(resultJson);

        Assert.NotNull(result);
        Assert.False(result.IsValid);
        Assert.Contains(result.Errors, e => e.Contains("Invalid JSON"));
    }

    [Fact]
    public void ValidateExtractedFields_ZeroHours_ReturnsError()
    {
        var fields = new ExtractedFields
        {
            Client = "Acme Corp",
            Project = "Phase 2",
            Hours = 0,
            Rate = 150,
            Currency = "USD",
            Date = "2026-04-01"
        };

        var resultJson = _plugin.ValidateExtractedFields(JsonSerializer.Serialize(fields));
        var result = JsonSerializer.Deserialize<ValidationResult>(resultJson);

        Assert.NotNull(result);
        Assert.False(result.IsValid);
        Assert.Contains(result.Errors, e => e.Contains("Hours"));
    }

    [Fact]
    public void ValidateExtractedFields_OptionalFieldsMissing_StillValid()
    {
        // Description and PoNumber are optional
        var fields = new ExtractedFields
        {
            Client = "Acme Corp",
            Project = "Phase 2",
            Hours = 3,
            Rate = 150,
            Currency = "USD",
            Date = "2026-04-01"
            // Description and PoNumber intentionally omitted
        };

        var resultJson = _plugin.ValidateExtractedFields(JsonSerializer.Serialize(fields));
        var result = JsonSerializer.Deserialize<ValidationResult>(resultJson);

        Assert.NotNull(result);
        Assert.True(result.IsValid);
    }
}