import type { EndpointInfo, ParsedSpec, ValidationResult, SchemaInfo } from '../lib/types.js';

export function formatMetadata(metadata: ParsedSpec): string {
  const lines = [
    `# ${metadata.title}`,
    `Version: ${metadata.version}`,
  ];

  if (metadata.description) {
    lines.push(`Description: ${metadata.description}`);
  }

  lines.push('');
  lines.push(`## Statistics`);
  lines.push(`- Paths: ${metadata.pathCount}`);
  lines.push(`- Operations: ${metadata.operationCount}`);
  lines.push(`- Schemas: ${metadata.schemaCount}`);
  if (metadata.webhookCount !== undefined && metadata.webhookCount > 0) {
    lines.push(`- Webhooks: ${metadata.webhookCount}`);
  }

  if (metadata.servers.length > 0) {
    lines.push('');
    lines.push(`## Servers`);
    metadata.servers.forEach(s => lines.push(`- ${s}`));
  }

  if (metadata.tags.length > 0) {
    lines.push('');
    lines.push(`## Tags`);
    metadata.tags.forEach(t => lines.push(`- ${t}`));
  }

  return lines.join('\n');
}

export function formatValidation(result: ValidationResult): string {
  const lines: string[] = [];

  if (result.valid) {
    lines.push('Validation: PASSED');
  } else {
    lines.push('Validation: FAILED');
  }

  if (result.errors.length > 0) {
    lines.push('');
    lines.push('## Errors');
    for (const err of result.errors) {
      const path = err.path ? `[${err.path}] ` : '';
      lines.push(`- ${path}${err.message}`);
    }
  }

  if (result.warnings.length > 0) {
    lines.push('');
    lines.push('## Warnings');
    for (const warn of result.warnings) {
      const path = warn.path ? `[${warn.path}] ` : '';
      lines.push(`- ${path}${warn.message}`);
    }
  }

  return lines.join('\n');
}

export function formatEndpoints(endpoints: EndpointInfo[]): string {
  if (endpoints.length === 0) {
    return 'No endpoints found matching criteria.';
  }

  const lines = [`Found ${endpoints.length} endpoint(s):`, ''];

  for (const ep of endpoints) {
    lines.push(`## ${ep.method.toUpperCase()} ${ep.path}`);

    if (ep.operationId) {
      lines.push(`Operation ID: ${ep.operationId}`);
    }

    if (ep.summary) {
      lines.push(`Summary: ${ep.summary}`);
    }

    if (ep.tags.length > 0) {
      lines.push(`Tags: ${ep.tags.join(', ')}`);
    }

    if (ep.parameters.length > 0) {
      lines.push('');
      lines.push('### Parameters');
      for (const param of ep.parameters) {
        const required = param.required ? ' (required)' : '';
        lines.push(`- **${param.name}** [${param.in}]${required}`);
        if (param.description) {
          lines.push(`  ${param.description}`);
        }
      }
    }

    if (ep.requestBody) {
      lines.push('');
      lines.push('### Request Body');
      const required = ep.requestBody.required ? ' (required)' : '';
      lines.push(`Content types${required}: ${ep.requestBody.contentTypes.join(', ')}`);
      if (ep.requestBody.description) {
        lines.push(ep.requestBody.description);
      }
    }

    if (ep.responses.length > 0) {
      lines.push('');
      lines.push('### Responses');
      for (const resp of ep.responses) {
        lines.push(`- **${resp.statusCode}**: ${resp.description || 'No description'}`);
      }
    }

    lines.push('');
  }

  return lines.join('\n');
}

export function formatSchema(schema: SchemaInfo): string {
  const lines = [
    `# ${schema.name}`,
  ];

  if (schema.description) {
    lines.push(schema.description);
  }

  if (schema.type) {
    lines.push(`Type: ${schema.type}`);
  }

  lines.push('');
  lines.push('## Schema');
  lines.push('```json');
  lines.push(JSON.stringify(schema.schema, null, 2));
  lines.push('```');

  return lines.join('\n');
}

export function formatTypes(types: string): string {
  return ['## Generated TypeScript Types', '', '```typescript', types, '```'].join('\n');
}