/**
 * POST /api/workflows/deploy
 * Deploy workflow to n8n via REST API
 * Worker handles this directly (mostly external API calls, minimal CPU)
 *
 * Pipeline gate: Validate → Simulate → Deploy
 * Deployment ≠ Activation (never auto-activate)
 */
import { Hono } from 'hono';
import { z } from 'zod';
import type { Env } from '../types/env';
import type { WorkflowJob, DeploymentResult } from '../types/workflow';
import { createAuditEvent } from '../utils/audit';

export const deployWorkflowRoute = new Hono<{ Bindings: Env }>();

const DeployRequestSchema = z.object({
  jobId: z.string().min(1),
});

deployWorkflowRoute.post('/deploy', async (c) => {
  const body = await c.req.json().catch(() => null);
  if (!body) return c.json({ success: false, error: 'Invalid JSON body' }, 400);

  const parsed = DeployRequestSchema.safeParse(body);
  if (!parsed.success) {
    return c.json({ success: false, error: 'Validation failed', details: parsed.error.flatten() }, 400);
  }

  const { jobId } = parsed.data;
  const raw = await c.env.WFO_CACHE.get(`job:${jobId}`, 'text');
  if (!raw) return c.json({ success: false, error: `Job ${jobId} not found` }, 404);

  const job = JSON.parse(raw) as WorkflowJob;

  // ─── Pipeline Gates ──────────────────────────────────────────────────────
  if (!job.compiledWorkflow) {
    return c.json({ success: false, error: 'Workflow not compiled. Run /generate first.' }, 409);
  }
  if (!job.validationReport?.valid) {
    return c.json({
      success: false,
      error: 'Workflow failed validation. Fix issues before deploying.',
      validationReport: job.validationReport,
    }, 409);
  }
  if (!job.simulationReport?.passed) {
    return c.json({
      success: false,
      error: 'Workflow failed dry-run simulation. Fix issues before deploying.',
      simulationReport: job.simulationReport,
    }, 409);
  }

  // ─── Credential check via n8n API ────────────────────────────────────────
  const credResp = await fetch(`${c.env.N8N_BASE_URL}/api/v1/credentials`, {
    headers: { 'X-N8N-API-KEY': c.env.N8N_API_KEY },
    signal: AbortSignal.timeout(8000),
  }).catch(() => null);

  let availableCredentials: Array<{ id: string; name: string; type: string }> = [];
  if (credResp?.ok) {
    const credData = await credResp.json() as { data: typeof availableCredentials };
    availableCredentials = credData.data ?? [];
  }

  // ─── Deploy to n8n (create or update) ────────────────────────────────────
  const workflowPayload = {
    ...job.compiledWorkflow,
    active: false, // NEVER activate on deploy
  };

  let n8nResponse: Response;
  let n8nWorkflowId = job.deploymentResult?.n8nWorkflowId;

  try {
    if (n8nWorkflowId) {
      // Update existing
      n8nResponse = await fetch(`${c.env.N8N_BASE_URL}/api/v1/workflows/${n8nWorkflowId}`, {
        method: 'PUT',
        headers: {
          'Content-Type': 'application/json',
          'X-N8N-API-KEY': c.env.N8N_API_KEY,
        },
        body: JSON.stringify(workflowPayload),
        signal: AbortSignal.timeout(10000),
      });
    } else {
      // Create new
      n8nResponse = await fetch(`${c.env.N8N_BASE_URL}/api/v1/workflows`, {
        method: 'POST',
        headers: {
          'Content-Type': 'application/json',
          'X-N8N-API-KEY': c.env.N8N_API_KEY,
        },
        body: JSON.stringify(workflowPayload),
        signal: AbortSignal.timeout(10000),
      });
    }
  } catch (err) {
    const msg = err instanceof Error ? err.message : 'n8n API unreachable';
    return c.json({ success: false, error: `Deployment failed: ${msg}`, jobId }, 502);
  }

  if (!n8nResponse.ok) {
    const errText = await n8nResponse.text();
    const deploymentResult: DeploymentResult = {
      jobId,
      status: 'failed',
      deployedAt: new Date().toISOString(),
      errorMessage: `n8n API ${n8nResponse.status}: ${errText}`,
    };

    await updateJobInKV(c.env.WFO_CACHE, jobId, job, {
      state: 'simulated', // revert to pre-deploy state
      deploymentResult,
      event: 'deployment.failed',
    });

    return c.json({ success: false, error: deploymentResult.errorMessage, deploymentResult, jobId }, 500);
  }

  const n8nData = await n8nResponse.json() as { id: string };
  n8nWorkflowId = n8nData.id;

  const deploymentResult: DeploymentResult = {
    jobId,
    n8nWorkflowId,
    status: 'success',
    deployedAt: new Date().toISOString(),
  };

  await updateJobInKV(c.env.WFO_CACHE, jobId, job, {
    state: 'deployed',
    deploymentResult,
    event: 'deployment.success',
    credentialAnalysis: {
      jobId,
      allCredentialsPresent: availableCredentials.length > 0,
      required: [],
      available: availableCredentials,
      missing: [],
      analysedAt: new Date().toISOString(),
    },
  });

  return c.json({
    success: true,
    jobId,
    n8nWorkflowId,
    deploymentResult,
    message: 'Workflow deployed successfully. It is NOT yet activated. Submit /approve to request activation.',
  });
});

async function updateJobInKV(
  kv: KVNamespace,
  jobId: string,
  job: WorkflowJob,
  updates: Partial<WorkflowJob> & { event: string },
) {
  const { event, ...rest } = updates;
  const updated: WorkflowJob = {
    ...job,
    ...rest,
    updatedAt: new Date().toISOString(),
    auditLog: [
      ...job.auditLog,
      createAuditEvent(jobId, event, 'system', rest as Record<string, unknown>),
    ],
  };
  await kv.put(`job:${jobId}`, JSON.stringify(updated), { expirationTtl: 86400 * 7 });
}