import { json } from '@sveltejs/kit';
import { DriftPlanChanged, previewDrift, runDriftDeployment } from '$lib/server/fleet/drift.js';
import { kick } from '$lib/server/pipeline/worker.js';

// GET returns the current drift plan for the whole fleet without touching disk.
export async function GET() {
    const plan = await previewDrift();
    const entries = plan.files.map(file => ({ ...file, size: file.afterSize ?? file.beforeSize ?? 0, sha256: file.afterSha256 ?? file.beforeSha256 ?? '' }));
    const byServer = new Map<
        string,
        Array<{ relPath: string; size: number; sha256: string; kind: string; driftKind: string }>
    >();
    for (const e of entries) {
        const arr = byServer.get(e.server) ?? [];
        arr.push({
            relPath: e.relPath,
            size: e.size,
            sha256: e.sha256,
            kind: e.kind,
            driftKind: e.driftKind
        });
        byServer.set(e.server, arr);
    }
    return json({
        totalDrift: entries.length, scannedAt: plan.scannedAt,
        servers: [...byServer.entries()].map(([server, files]) => ({ server, files }))
    });
}

// POST removes drift and creates a drift deployment. Body: { servers?: string[], dryRun?: boolean }
export async function POST({ request }: { request: Request }) {
    const body = await request.json().catch(() => null);
    if (!body || (body.servers !== undefined && (!Array.isArray(body.servers) || !body.servers.every((server: unknown) => typeof server === 'string')))) {
        return json({ ok: false, error: 'Provide the server IDs to review.' }, { status: 400 });
    }
    try {
        if (body.dryRun === true) return json({ ok: true, plan: await previewDrift(body.servers) });
        if (typeof body.expectedFingerprint !== 'string' || !body.expectedFingerprint) return json({ ok: false, error: 'Review a reconciliation plan before applying changes.' }, { status: 400 });
        const result = await runDriftDeployment({ servers: body.servers, expectedFingerprint: body.expectedFingerprint, triggeredBy: 'ui' });
        if (result.deploymentId) void kick();
        return json({ ok: true, result });
    } catch (error) {
        if (error instanceof DriftPlanChanged) return json({ ok: false, error: error.message, plan: error.plan }, { status: 409 });
        return json({ ok: false, error: (error as Error).message }, { status: 400 });
    }
}