import { z } from 'zod';
import type { LlmClient } from '@/lib/ai/llm-client';
import { GeminiLlmClient } from '@/lib/ai/gemini-client';
import { clamp, nowIso, loadPhaseContainers, persistPhaseArtifacts } from '@/lib/server/projects';
import type { MarketingModel } from '@/lib/types/marketing';

const HomepageMessagingSchema = z.object({
  headline: z.string().nullable(),
  subheadline: z.string().nullable(),
  bullets: z.array(z.string()).default([]),
});

const MarketingModelSchema = z.object({
  projectId: z.string(),
  icp: z.array(z.string()).default([]),
  positioning: z.string().nullable(),
  homepageMessaging: HomepageMessagingSchema,
  initialChannels: z.array(z.string()).default([]),
  launchAngles: z.array(z.string()).default([]),
  overallConfidence: z.number().min(0).max(1),
});

export async function runMarketingPlanning(
  projectId: string,
  llmClient?: LlmClient,
): Promise<MarketingModel> {
  const { phaseData } = await loadPhaseContainers(projectId);
  const canonical = phaseData.canonicalProductModel;
  if (!canonical) {
    throw new Error('Canonical product model missing. Run buildCanonicalProductModel first.');
  }

  const llm = llmClient ?? new GeminiLlmClient();
  const systemPrompt =
    'You are a SaaS marketing strategist. Given the canonical product model, produce ICP, positioning, homepage messaging, and launch ideas as strict JSON.';

  const marketing = await llm.structuredCall<MarketingModel>({
    model: 'gemini',
    systemPrompt,
    messages: [
      {
        role: 'user',
        content: [
          'Canonical product model JSON:',
          '```json',
          JSON.stringify(canonical, null, 2),
          '```',
          'Respond ONLY with valid JSON that matches the required schema.',
        ].join('\n'),
      },
    ],
    schema: MarketingModelSchema,
    temperature: 0.2,
  });

  await persistPhaseArtifacts(projectId, (phaseData, phaseScores, phaseHistory) => {
    phaseData.marketingPlan = marketing;
    phaseScores.marketing = {
      overallCompletion: clamp(marketing.homepageMessaging.bullets.length ? 0.7 : 0.5),
      overallConfidence: marketing.overallConfidence,
      updatedAt: nowIso(),
    };
    phaseHistory.push({ phase: 'marketing', status: 'completed', timestamp: nowIso() });
    return { phaseData, phaseScores, phaseHistory, nextPhase: 'marketing_ready' };
  });

  return marketing;
}