#!/usr/bin/env node
// ═══════════════════════════════════════════════════════════════════════════
// SIL Provenance — Revisionsspår för varje slutsats
// Erik-krav: "För varje slutsats vill jag kunna svara på:
//   - Vilka observationer användes?
//   - Vilka regler aktiverades?
//   - Vilka grafnoder traverserades?
//   - Vilka relationer användes?
//   - Vilka confidence-värden påverkade slutsatsen?
//   - Vilken del var verifierad och vilken del var inferens?"
// ═══════════════════════════════════════════════════════════════════════════

import { readFileSync } from 'fs';

/**
 * ProvenanceTracker — Spårar hur varje slutsats i SIL nåddes
 */
export class ProvenanceTracker {
  constructor(graph) {
    this.graph = graph;
    this.traces = [];
  }

  /**
   * Starta en ny spårning för en analys
   */
  startTrace(analysisId, context) {
    const trace = {
      id: analysisId,
      timestamp: new Date().toISOString(),
      context,
      steps: [],
      conclusions: []
    };
    this.traces.push(trace);
    return trace;
  }

  /**
   * Logga ett steg i resonemangskedjan
   */
  logStep(trace, step) {
    const entry = {
      order: trace.steps.length + 1,
      type: step.type, // 'observation', 'rule', 'traversal', 'inference', 'verification'
      description: step.description,
      inputs: step.inputs || [],
      output: step.output,
      confidence: step.confidence || 1.0,
      verified: step.verified || false,
      source: step.source || 'unknown',
      timestamp: new Date().toISOString()
    };

    trace.steps.push(entry);
    return entry;
  }

  /**
   * Logga en slutsats
   */
  logConclusion(trace, conclusion) {
    const entry = {
      order: trace.conclusions.length + 1,
      conclusion: conclusion.text,
      confidence: conclusion.confidence,
      basis: conclusion.basis || [], // vilka steg som ledde hit
      verified: conclusion.verified || false,
      verificationMethod: conclusion.verificationMethod || null,
      inferred: conclusion.inferred || false,
      timestamp: new Date().toISOString()
    };

    trace.conclusions.push(entry);
    return entry;
  }

  /**
   * Hämta komplett spår för en analys
   */
  getTrace(analysisId) {
    return this.traces.find(t => t.id === analysisId);
  }

  /**
   * Generera mänskligt läsbar förklaring av hur en slutsats nåddes
   */
  explainConclusion(analysisId, conclusionIndex = 0) {
    const trace = this.getTrace(analysisId);
    if (!trace) return null;

    const conclusion = trace.conclusions[conclusionIndex];
    if (!conclusion) return null;

    const explanation = {
      conclusion: conclusion.conclusion,
      confidence: conclusion.confidence,
      how: [],
      verified: conclusion.verified,
      inferred: conclusion.inferred
    };

    // För varje basis-steg, förklara
    for (const stepId of conclusion.basis) {
      const step = trace.steps.find(s => s.order === stepId);
      if (!step) continue;

      explanation.how.push({
        type: step.type,
        description: step.description,
        confidence: step.confidence,
        verified: step.verified,
        source: step.source
      });
    }

    return explanation;
  }

  /**
   * Exportera spår i JSONL-format för persistent lagring
   */
  exportTrace(trace) {
    return JSON.stringify(trace);
  }
}

/**
 * Integrera med PRAnalyzer — lägg till provenance-spårning
 */
export function withProvenance(AnalyzerClass) {
  return class extends AnalyzerClass {
    constructor(...args) {
      super(...args);
      this.provenance = new ProvenanceTracker(this.graph);
    }

    analyzePR(repoPath, baseBranch = 'main', headBranch = 'HEAD') {
      const analysisId = `pr-${Date.now()}`;
      const trace = this.provenance.startTrace(analysisId, {
        repo: repoPath,
        baseBranch,
        headBranch
      });

      // Steg 1: Observation — hämta diff
      this.provenance.logStep(trace, {
        type: 'observation',
        description: 'Hämta git diff för PR',
        inputs: [`${baseBranch}...${headBranch}`],
        output: 'diff_files_list',
        confidence: 0.99,
        verified: true,
        source: 'git'
      });

      const diffFiles = this.getDiffFiles(repoPath, baseBranch, headBranch);

      // Steg 2: Observation — identifiera ändrade filer
      this.provenance.logStep(trace, {
        type: 'observation',
        description: 'Identifiera ändrade filer från diff',
        inputs: diffFiles,
        output: `${diffFiles.length} filer identifierade`,
        confidence: 0.99,
        verified: true,
        source: 'git'
      });

      // Steg 3: Regel — mappa filer till komponenter
      const changedComponents = this.identifyChangedComponents(diffFiles, repoPath);

      for (const comp of changedComponents) {
        this.provenance.logStep(trace, {
          type: 'rule',
          description: `Mappa fil ${comp.file} till komponent ${comp.name}`,
          inputs: [comp.file],
          output: comp.id,
          confidence: comp.confidence,
          verified: comp.source === 'AST' || comp.source === 'DB_MIGRATION',
          source: comp.source
        });
      }

      // Steg 4: Traversal — traversera grafen
      const impact = this.analyzeImpact(changedComponents);

      for (const indirect of impact.indirect) {
        const edge = this.graph.edges.find(e =>
          e.from === changedComponents.find(c => c.name === indirect.from)?.id &&
          e.to === this.graph.nodes.find(n => n.label === indirect.to)?.id
        );

        this.provenance.logStep(trace, {
          type: 'traversal',
          description: `Traversera kant: ${indirect.from} → ${indirect.to}`,
          inputs: [indirect.from],
          output: indirect.to,
          confidence: edge?.confidence || indirect.confidence,
          verified: false, // kräver runtime-verifiering
          source: 'graph_traversal'
        });
      }

      // Steg 5: Inferens — affärspåverkan
      const businessImpact = this.analyzeBusinessImpact(impact);

      for (const bi of businessImpact) {
        this.provenance.logStep(trace, {
          type: 'inference',
          description: `Härled affärspåverkan: ${bi.process} påverkas`,
          inputs: impact.indirect.map(i => i.to),
          output: bi.process,
          confidence: 0.75, // inferens har lägre confidence
          verified: false,
          source: 'business_rule'
        });
      }

      // Steg 6: Slutsatser
      const report = super.analyzePR(repoPath, baseBranch, headBranch);

      // Logga slutsatser med provenance
      for (const comp of changedComponents) {
        this.provenance.logConclusion(trace, {
          text: `${comp.name} är en ändrad komponent`,
          confidence: comp.confidence,
          basis: trace.steps
            .filter(s => s.output === comp.id || s.inputs.includes(comp.file))
            .map(s => s.order),
          verified: true,
          verificationMethod: 'git_diff',
          inferred: false
        });
      }

      for (const indirect of impact.indirect) {
        this.provenance.logConclusion(trace, {
          text: `${indirect.to} påverkas indirekt av ändring i ${indirect.from}`,
          confidence: indirect.confidence,
          basis: trace.steps
            .filter(s => s.type === 'traversal' && s.output === indirect.to)
            .map(s => s.order),
          verified: false,
          verificationMethod: null,
          inferred: true
        });
      }

      // Lägg till provenance i rapporten
      report.provenance = {
        analysisId,
        trace: this.provenance.exportTrace(trace),
        explanation: this.provenance.explainConclusion(analysisId, 0)
      };

      return report;
    }
  };
}

// ── CLI för att inspektera provenance ─────────────────────────────────────

if (import.meta.url === `file://${process.argv[1]}`) {
  const command = process.argv[2];

  if (command === '--explain') {
    const traceFile = process.argv[3];
    const conclusionIndex = parseInt(process.argv[4]) || 0;

    try {
      const trace = JSON.parse(readFileSync(traceFile, 'utf8'));
      const tracker = new ProvenanceTracker({});
      tracker.traces.push(trace);

      const explanation = tracker.explainConclusion(trace.id, conclusionIndex);
      console.log(JSON.stringify(explanation, null, 2));
    } catch (e) {
      console.error('Fel:', e.message);
    }
  } else {
    console.log('Användning:');
    console.log('  node provenance.mjs --explain <trace-file> [conclusion-index]');
  }
}