import { Prisma } from "@prisma/client";
import { db } from "@/lib/db";
import { PipelineError } from "./errors";
import { applyTransition } from "./transitions";
import { getConfigNumber, getPreviewConfig } from "./config";

/** Slate date format used by the panel's getDateString (YYYY/MM/DD). */
function slateDate(d = new Date()): string {
  const mm = String(d.getMonth() + 1).padStart(2, "0");
  const dd = String(d.getDate()).padStart(2, "0");
  return `${d.getFullYear()}/${mm}/${dd}`;
}

export interface PreviewManifest {
  stage: "PREVIEW";
  exportId: string;
  shotCode: string;
  versionString: string;
  outputDir: string;
  outputPattern: string;
  frameStart: number;
  frameEnd: number;
  fps: number;
  templateAep: string;
  templateComp: string;
  overlayComp: string;
  lutComp: string;
  movTemplate: string;
  mp4Template: string;
  movOutput: string;
  mp4Output: string;
  slateScopeProp: string;
  slateSubmissionProp: string;
  slate: {
    versionName: string;
    date: string;
    description: string | null;
    notes: string | null;
    shotCode: string;
    episode: string | null;
    scene: string | null;
    vfxScope: string | null;
    submissionNote: string | null;
  };
}

type ExportForPreview = {
  id: string;
  shotId: string;
  versionString: string;
  outputDir: string;
  outputPattern: string;
  frameStart: number;
  frameEnd: number;
  fps: number;
  vfxScope: string | null;
  submissionNote: string | null;
};

/**
 * Builds the PREVIEW_ONLY job manifest (RenderPipeline2 §9): everything the
 * headless AE build script needs to rebuild the shot around the rendered EXRs
 * and queue the delivery MOV + review MP4.
 *
 * The MOV and MP4 are written beside the EXR sequence, so every artifact for a
 * version lives in one folder and Phase 5 can package them together.
 */
export async function buildPreviewManifest(exportRow: ExportForPreview): Promise<PreviewManifest> {
  const shot = await db.shot.findUnique({
    where: { id: exportRow.shotId },
    select: { shotCode: true, episode: true, scene: true, description: true, notes: true },
  });
  if (!shot) throw new PipelineError(404, "Shot not found for export");

  const cfg = await getPreviewConfig();
  const base = `${shot.shotCode}_cmp_TT_${exportRow.versionString}`;

  return {
    stage: "PREVIEW",
    exportId: exportRow.id,
    shotCode: shot.shotCode,
    versionString: exportRow.versionString,
    outputDir: exportRow.outputDir,
    outputPattern: exportRow.outputPattern,
    frameStart: exportRow.frameStart,
    frameEnd: exportRow.frameEnd,
    fps: exportRow.fps,
    templateAep: cfg.templateAep,
    templateComp: cfg.templateComp,
    overlayComp: cfg.overlayComp,
    lutComp: cfg.lutComp,
    movTemplate: cfg.movTemplate,
    mp4Template: cfg.mp4Template,
    movOutput: `${exportRow.outputDir}/${base}.mov`,
    mp4Output: `${exportRow.outputDir}/${base}.mp4`,
    slateScopeProp: cfg.slateScopeProp,
    slateSubmissionProp: cfg.slateSubmissionProp,
    slate: {
      versionName: base,
      date: slateDate(),
      description: shot.description,
      notes: shot.notes,
      shotCode: shot.shotCode,
      episode: shot.episode,
      scene: shot.scene,
      vfxScope: exportRow.vfxScope,
      submissionNote: exportRow.submissionNote,
    },
  };
}

/** Creates the PREVIEW_ONLY job that follows a successful EXR render. */
export async function createPreviewJob(
  tx: Prisma.TransactionClient,
  exportRow: ExportForPreview,
  manifest: PreviewManifest,
  maxAttempts: number,
  priority: number
) {
  return tx.renderJob.create({
    data: {
      type: "PREVIEW_ONLY",
      exportId: exportRow.id,
      attempt: 1,
      maxAttempts,
      priority,
      manifest: manifest as unknown as Prisma.InputJsonValue,
    },
  });
}

export interface FinalizeInput {
  artifacts?: {
    deliveryMovPath?: string;
    previewMovKey?: string;
    thumbnailKey?: string;
    metadataKey?: string;
    logFileKey?: string;
  };
  renderStats?: { renderSeconds?: number; previewSeconds?: number };
  media?: { width?: number; height?: number; frameCount?: number; fps?: number; fileName?: string };
}

/**
 * E13 — preview artifacts are done: register the review MP4 as an ordinary
 * `Version` and move the Export to READY_FOR_QC.
 *
 * Pipeline mode (§6.4 / T12): the Version is **never client-visible** and
 * **no task or shot status is touched**. Delivery QC runs on shots the client
 * has usually already approved, so a post-approval technical render must not
 * resurface in the review flow or the client portal.
 */
export async function finalizePreview(jobId: string, machineId: string, body: FinalizeInput) {
  return db.$transaction(async (tx) => {
    const job = await tx.renderJob.findUnique({
      where: { id: jobId },
      include: { export: true },
    });
    if (!job) throw new PipelineError(404, "Render job not found");
    if (job.machineId !== machineId) {
      throw new PipelineError(409, "Job is not held by this machine (lease reassigned?)");
    }
    const exportRow = job.export;
    if (!exportRow) throw new PipelineError(422, "Job has no export to finalize");

    if (exportRow.status === "READY_FOR_QC" && exportRow.versionId) {
      return {
        export: { id: exportRow.id, status: exportRow.status },
        version: { id: exportRow.versionId },
        alreadyApplied: true,
      };
    }

    const artifacts = body.artifacts ?? {};
    const media = body.media ?? {};

    await tx.renderJob.update({
      where: { id: job.id },
      data: {
        status: "COMPLETED",
        progress: 1,
        finishedAt: new Date(),
        exitCode: 0,
        logFileKey: artifacts.logFileKey ?? job.logFileKey,
      },
    });

    let versionId: string | null = null;
    if (artifacts.previewMovKey) {
      // Version numbering stays monotonic for the task (existing review flows
      // rely on the newest version having the highest number) while matching
      // the export version whenever it is ahead.
      const taskMax = exportRow.taskId
        ? await tx.version.aggregate({
            where: { taskId: exportRow.taskId },
            _max: { versionNumber: true },
          })
        : { _max: { versionNumber: null as number | null } };
      const versionNumber = Math.max((taskMax._max.versionNumber ?? 0) + 1, exportRow.versionNumber);

      if (exportRow.taskId) {
        await tx.version.updateMany({
          where: { taskId: exportRow.taskId },
          data: { isLatest: false },
        });
      }

      const version = await tx.version.create({
        data: {
          versionNumber,
          shotId: exportRow.shotId,
          taskId: exportRow.taskId,
          artistId: exportRow.submittedById,
          fileUrl: `/api/files/${artifacts.previewMovKey}`,
          fileName: media.fileName ?? `${exportRow.versionString}.mp4`,
          mimeType: "video/mp4",
          thumbnailUrl: artifacts.thumbnailKey ? `/api/files/${artifacts.thumbnailKey}` : undefined,
          fps: media.fps ?? exportRow.fps,
          frameCount: media.frameCount ?? exportRow.frameEnd - exportRow.frameStart + 1,
          width: media.width ?? exportRow.width,
          height: media.height ?? exportRow.height,
          notes: `Pipeline render ${exportRow.versionString} (internal only)`,
          isLatest: true,
          isClientVisible: false, // never shared to the client portal (§10.0)
        },
      });
      versionId = version.id;
    }

    const updated = await applyTransition(
      tx,
      exportRow,
      "READY_FOR_QC",
      {
        type: "WORKER",
        id: machineId,
        note: `Preview complete in ${body.renderStats?.previewSeconds ?? "?"}s${versionId ? " — review version created" : " — no preview media reported"}`,
      },
      {
        ...(versionId ? { versionId } : {}),
        ...(artifacts.deliveryMovPath ? { deliveryMovPath: artifacts.deliveryMovPath } : {}),
        ...(artifacts.previewMovKey ? { previewMovKey: artifacts.previewMovKey } : {}),
        ...(artifacts.thumbnailKey ? { thumbnailKey: artifacts.thumbnailKey } : {}),
        ...(artifacts.metadataKey ? { metadataKey: artifacts.metadataKey } : {}),
      }
    );

    return {
      export: { id: updated.id, status: updated.status },
      version: versionId ? { id: versionId } : null,
      alreadyApplied: false,
    };
  });
}

/** T11 — retry the preview stage only; validated EXRs are left alone. */
export async function retryPreview(exportId: string, actorId?: string) {
  const maxAttempts = await getConfigNumber("render.maxAttempts");

  return db.$transaction(async (tx) => {
    const exportRow = await tx.export.findUnique({ where: { id: exportId } });
    if (!exportRow) throw new PipelineError(404, "Export not found");
    if (exportRow.status !== "PREVIEW_FAILED") {
      throw new PipelineError(409, `Export is ${exportRow.status} — only PREVIEW_FAILED exports can retry the preview`);
    }

    const manifest = await buildPreviewManifest(exportRow);
    const last = await tx.renderJob.findFirst({
      where: { exportId, type: "PREVIEW_ONLY" },
      orderBy: { attempt: "desc" },
    });

    const job = await tx.renderJob.create({
      data: {
        type: "PREVIEW_ONLY",
        exportId,
        attempt: (last?.attempt ?? 0) + 1,
        maxAttempts,
        priority: last?.priority ?? 50,
        manifest: manifest as unknown as Prisma.InputJsonValue,
      },
    });

    const updated = await applyTransition(tx, exportRow, "GENERATING_PREVIEW", {
      type: "USER",
      id: actorId,
      note: `Retry preview (attempt ${job.attempt})`,
    });

    return {
      export: { id: updated.id, status: updated.status },
      renderJob: { id: job.id, attempt: job.attempt },
    };
  });
}