using System.Text.Json;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Logging;
using TeamUp.Modules.Assembler.Domain;
using TeamUp.Modules.Assembler.Persistence;
using TeamUp.SharedKernel.Ai;

namespace TeamUp.Modules.Assembler.Runtime;

internal sealed record AgentRunPayload(Guid RunId);

/// <summary>
/// Processes one claimed job end to end: resolve the run context (OrgBoard) + skills (Skills) →
/// assemble the prompt → call the model (BYOK, with fallback) → parse into an action + risk tag,
/// all captured on the AgentRun — then hand the proposal to the action gate (Governance), which
/// executes it or holds it in the review inbox.
/// </summary>
internal sealed class AgentRunExecutor(
    AssemblerDbContext db,
    IAgentRunContextProvider contextProvider,
    ISkillCatalog skillCatalog,
    IApiConfigResolver configResolver,
    IModelClient modelClient,
    IActionGate actionGate,
    ITeamMemory teamMemory,
    TimeProvider clock,
    ILogger<AgentRunExecutor> logger)
{
    public async Task ProcessAsync(Job job, CancellationToken cancellationToken = default)
    {
        AgentRun? run = null;
        try
        {
            var payload = JsonSerializer.Deserialize<AgentRunPayload>(job.Payload)
                ?? throw new InvalidOperationException("Invalid job payload.");
            run = await db.AgentRuns.FirstOrDefaultAsync(r => r.Id == payload.RunId, cancellationToken)
                ?? throw new InvalidOperationException($"AgentRun {payload.RunId} not found.");

            var context = await contextProvider.GetAsync(run.SeatId, run.WorkItemId, cancellationToken)
                ?? throw new InvalidOperationException("Agent or task not found for the run.");

            var skills = await skillCatalog.GetByKeysAsync(context.OrganizationId, context.SkillKeys, cancellationToken);

            // Working memory: recall the team's most relevant decisions/corrections for this task.
            var memories = await teamMemory.SearchAsync(
                context.TeamId, context.TaskTitle + "\n" + context.TaskDescription, take: 3, cancellationToken);

            var assembled = PromptAssembler.Build(context, skills, memories);

            run.Start(context.AgentId, assembled.Prompt, assembled.Trace);
            await db.SaveChangesAsync(cancellationToken);

            var config = await configResolver.ResolveAsync(context.ApiConfigId, cancellationToken)
                ?? (context.FallbackApiConfigId is { } fallback
                    ? await configResolver.ResolveAsync(fallback, cancellationToken)
                    : null)
                ?? throw new InvalidOperationException("No usable model config for the agent.");

            var completion = await modelClient.CompleteAsync(
                new ModelRequest(config.Provider, config.Model, config.ApiKey, config.Endpoint, assembled.Prompt, MaxTokens: 512),
                cancellationToken);

            if (!completion.Success)
            {
                var error = completion.Error ?? "Model call failed.";
                run.Fail(error, clock.GetUtcNow());
                job.MarkFailed(error, clock.GetUtcNow());
                await db.SaveChangesAsync(cancellationToken);
                return;
            }

            var result = JsonSerializer.Serialize(new
            {
                action = assembled.PrimaryAction,
                risk = assembled.PrimaryActionRisk,
                skill = context.SkillKeys.Count > 0 ? context.SkillKeys[0] : null,
            });

            var output = completion.Text ?? string.Empty;
            run.Complete(output, assembled.PrimaryAction, assembled.PrimaryActionRisk, result, completion.LatencyMs, clock.GetUtcNow());
            await db.SaveChangesAsync(cancellationToken);

            // Hand the parsed action to the gate: autonomy vs risk → execute now or hold in review.
            var gate = await actionGate.EvaluateAsync(
                new AgentActionProposal(
                    run.Id, run.SeatId, context.AgentId, run.WorkItemId, context.TeamId, context.OrganizationId,
                    context.Autonomy, assembled.PrimaryAction, assembled.PrimaryActionRisk,
                    context.TaskTitle, output, OutputParser.ExtractChildTitles(output), assembled.Trace),
                cancellationToken);
            logger.LogInformation(
                "Run {RunId}: {Action} ({Risk}) → {Outcome}.",
                run.Id, assembled.PrimaryAction, assembled.PrimaryActionRisk, gate.Outcome);

            job.MarkDone(clock.GetUtcNow());
            await db.SaveChangesAsync(cancellationToken);
        }
        catch (Exception ex)
        {
            run?.Fail(ex.Message, clock.GetUtcNow());
            job.MarkFailed(ex.Message, clock.GetUtcNow());
            await db.SaveChangesAsync(cancellationToken);
            logger.LogError(ex, "Agent-run job {JobId} failed.", job.Id);
        }
    }
}