using MeetingAssistant;
using MeetingAssistant.MeetingNotes;
using MeetingAssistant.Summary;
using Microsoft.Extensions.Options;

namespace MeetingAssistant.Tests;

public sealed class MeetingSummaryInstructionBuilderTests
{
    [Fact]
    public async Task BuilderAddsBoundMetadataWithoutAgentsAndRequestGuidanceToCustomPrompt()
    {
        var root = Path.Combine(Path.GetTempPath(), "meeting-assistant-tests", Guid.NewGuid().ToString("N"));
        var projectsRoot = Path.Combine(root, "Projects");
        var artifacts = CreateArtifacts(root);
        await WriteMeetingNoteAsync(artifacts.MeetingNotePath, ["Alpha"]);
        Directory.CreateDirectory(Path.Combine(projectsRoot, "Alpha"));
        await File.WriteAllTextAsync(Path.Combine(projectsRoot, "Alpha", "PROJECT.md"),
            "---\nname: Alpha Platform\ndescription: Builds meeting automation\n---\nInternal notes");
        await WriteProjectAgentsAsync(projectsRoot, "Unbound", "Do not expose these instructions");
        var builder = new MeetingSummaryInstructionBuilder(Options.Create(new MeetingAssistantOptions
        {
            Agent = new AgentOptions { InitialPrompt = "Custom base." },
            Vault = new VaultOptions { ProjectsFolder = projectsRoot }
        }));

        var instructions = await builder.BuildAsync(artifacts, CancellationToken.None);

        Assert.StartsWith("Custom base.", instructions);
        Assert.Contains("# Alpha", instructions);
        Assert.Contains("Alpha Platform", instructions);
        Assert.Contains("Builds meeting automation", instructions);
        Assert.Contains("PROJECT.md", instructions);
        Assert.Contains("256", instructions);
        Assert.Contains("request_project_association", instructions);
        Assert.Contains("request_workflow_change", instructions);
        Assert.DoesNotContain("Internal notes", instructions);
        Assert.DoesNotContain("Do not expose", instructions);
    }

    [Fact]
    public async Task BuilderUsesDefaultPromptWhenConfiguredPromptIsBlank()
    {
        var root = Path.Combine(Path.GetTempPath(), "meeting-assistant-tests", Guid.NewGuid().ToString("N"));
        var artifacts = CreateArtifacts(root);
        await WriteMeetingNoteAsync(artifacts.MeetingNotePath, []);
        var builder = new MeetingSummaryInstructionBuilder(Options.Create(new MeetingAssistantOptions
        {
            Agent = new AgentOptions { InitialPrompt = " " },
            Vault = new VaultOptions { ProjectsFolder = Path.Combine(root, "Projects") }
        }));

        var instructions = await builder.BuildAsync(artifacts, CancellationToken.None);

        Assert.Contains("You are the Meeting Assistant summary agent.", instructions);
        Assert.Contains("include only the most relevant cropped screenshots", instructions);
        Assert.Contains("Do not include every cropped screenshot", instructions);
        Assert.Contains("encode spaces in image-link targets as `%20`", instructions);
        Assert.Contains("Use add_attendee and remove_attendee", instructions);
        Assert.Contains("partial screenshot", instructions);
        Assert.Contains("override_speaker", instructions);
        Assert.Contains("very certain", instructions);
        Assert.Contains("merge=true", instructions);
        Assert.Contains("delete_identity", instructions);
        Assert.Contains("wrongfully matched", instructions);
        Assert.Contains("oneliner", instructions);
        Assert.Contains("very short", instructions);
        Assert.Contains("conciseness is more important", instructions);
        Assert.Contains("generated default title", instructions);
        Assert.Contains("purpose of the meeting is clear", instructions);
        Assert.Contains("title parameter", instructions);
    }

    [Fact]
    public async Task DefaultPromptTreatsAssistantContextAsMeetingMemoryForUncertainty()
    {
        var root = Path.Combine(Path.GetTempPath(), "meeting-assistant-tests", Guid.NewGuid().ToString("N"));
        var artifacts = CreateArtifacts(root);
        await WriteMeetingNoteAsync(artifacts.MeetingNotePath, []);
        var builder = new MeetingSummaryInstructionBuilder(Options.Create(new MeetingAssistantOptions
        {
            Agent = new AgentOptions { InitialPrompt = " " },
            Vault = new VaultOptions { ProjectsFolder = Path.Combine(root, "Projects") }
        }));

        var instructions = await builder.BuildAsync(artifacts, CancellationToken.None);

        Assert.Contains("meeting-specific memory", instructions);
        Assert.Contains("unexpected problems", instructions);
        Assert.Contains("missing information", instructions);
        Assert.Contains("assumptions", instructions);
        Assert.Contains("write_context", instructions);
    }

    [Fact]
    public async Task BuilderUsesConfiguredPrompt()
    {
        var root = Path.Combine(Path.GetTempPath(), "meeting-assistant-tests", Guid.NewGuid().ToString("N"));
        var artifacts = CreateArtifacts(root);
        await WriteMeetingNoteAsync(artifacts.MeetingNotePath, []);
        var builder = new MeetingSummaryInstructionBuilder(Options.Create(new MeetingAssistantOptions
        {
            Agent = new AgentOptions { InitialPrompt = "Custom summarizer instructions." },
            Vault = new VaultOptions { ProjectsFolder = Path.Combine(root, "Projects") }
        }));

        var instructions = await builder.BuildAsync(artifacts, CancellationToken.None);

        Assert.StartsWith("Custom summarizer instructions.", instructions);
        Assert.Contains("request_project_association", instructions);
    }

    [Fact]
    public async Task BuilderAppendsAgentsFilesForBoundProjects()
    {
        var root = Path.Combine(Path.GetTempPath(), "meeting-assistant-tests", Guid.NewGuid().ToString("N"));
        var projectsRoot = Path.Combine(root, "Projects");
        var artifacts = CreateArtifacts(root);
        await WriteMeetingNoteAsync(artifacts.MeetingNotePath, ["Beta", "Alpha", "Missing"]);
        await WriteProjectAgentsAsync(projectsRoot, "Alpha", "Alpha instructions.");
        await WriteProjectAgentsAsync(projectsRoot, "Beta", "Beta instructions.");
        Directory.CreateDirectory(Path.Combine(projectsRoot, "Missing"));
        var builder = new MeetingSummaryInstructionBuilder(Options.Create(new MeetingAssistantOptions
        {
            Agent = new AgentOptions { InitialPrompt = "Base." },
            Vault = new VaultOptions { ProjectsFolder = projectsRoot }
        }));

        var instructions = await builder.BuildAsync(artifacts, CancellationToken.None);

        Assert.StartsWith("Base.", instructions);
        Assert.Contains("---\nprojects:", NormalizeLineEndings(instructions));
        Assert.Contains("# Alpha", instructions);
        Assert.Contains("Alpha instructions.", instructions);
        Assert.Contains("# Beta", instructions);
        Assert.Contains("Beta instructions.", instructions);
    }

    private static MeetingSessionArtifacts CreateArtifacts(string root)
    {
        return new MeetingSessionArtifacts(
            Path.Combine(root, "Meetings", "Notes", "meeting.md"),
            Path.Combine(root, "Meetings", "Transcripts", "transcript.md"),
            Path.Combine(root, "Meetings", "Assistant Context", "context.md"),
            Path.Combine(root, "Meetings", "Summaries", "summary.md"));
    }

    private static async Task WriteMeetingNoteAsync(string path, IReadOnlyList<string> projects)
    {
        Directory.CreateDirectory(Path.GetDirectoryName(path)!);
        var projectLines = projects.Count == 0
            ? "projects: []"
            : "projects:\n" + string.Join('\n', projects.Select(project => $"- {project}"));
        await File.WriteAllTextAsync(
            path,
            $"""
            ---
            title: Meeting
            {projectLines}
            ---
            """);
    }

    private static async Task WriteProjectAgentsAsync(string projectsRoot, string project, string content)
    {
        var folder = Path.Combine(projectsRoot, project);
        Directory.CreateDirectory(folder);
        await File.WriteAllTextAsync(Path.Combine(folder, "AGENTS.md"), content);
    }

    private static string NormalizeLineEndings(string value)
    {
        return value.Replace("\r\n", "\n", StringComparison.Ordinal);
    }
}