/**
 * REST API client for Web Inspector backend.
 * Uses native fetch (Node 20+) with AbortController timeout.
 */

const DEFAULT_TIMEOUT = 120_000; // 120 seconds

export class ApiClient {
  constructor(private baseUrl: string) {
    // Strip trailing slash
    this.baseUrl = baseUrl.replace(/\/+$/, "");
  }

  // ── Single-page inspection ──────────────────────────────

  async startInspection(
    url: string,
    accessibilityStandard?: string,
  ): Promise<{ inspection_id: string; status: string }> {
    const body: Record<string, unknown> = { url };
    if (accessibilityStandard) body.accessibility_standard = accessibilityStandard;
    return this.post("/api/inspections", body);
  }

  async getInspection(inspectionId: string): Promise<InspectionResult> {
    return this.get(`/api/inspections/${inspectionId}`);
  }

  async getIssues(
    inspectionId: string,
    category?: string,
    severity?: string,
  ): Promise<IssuesResult> {
    const params = new URLSearchParams();
    if (category) params.set("category", category);
    if (severity) params.set("severity", severity);
    const qs = params.toString();
    return this.get(`/api/inspections/${inspectionId}/issues${qs ? `?${qs}` : ""}`);
  }

  async getInspections(
    url?: string,
    limit = 10,
  ): Promise<InspectionsListResult> {
    const params = new URLSearchParams({ limit: String(limit) });
    if (url) params.set("url", url);
    return this.get(`/api/inspections?${params.toString()}`);
  }

  // ── Site-wide inspection ────────────────────────────────

  async startSiteInspection(
    url: string,
    maxPages?: number,
    maxDepth?: number,
    accessibilityStandard?: string,
  ): Promise<{ site_inspection_id: string; status: string }> {
    const body: Record<string, unknown> = { url };
    if (maxPages !== undefined) body.max_pages = maxPages;
    if (maxDepth !== undefined) body.max_depth = maxDepth;
    if (accessibilityStandard) body.accessibility_standard = accessibilityStandard;
    return this.post("/api/site-inspections", body);
  }

  async getSiteInspection(siteInspectionId: string): Promise<SiteInspectionResult> {
    return this.get(`/api/site-inspections/${siteInspectionId}`);
  }

  async getSiteInspections(limit = 10): Promise<SiteInspectionsListResult> {
    return this.get(`/api/site-inspections?limit=${limit}`);
  }

  // ── HTTP helpers ────────────────────────────────────────

  private async get<T>(path: string): Promise<T> {
    return this.request("GET", path);
  }

  private async post<T>(path: string, body: unknown): Promise<T> {
    return this.request("POST", path, body);
  }

  private async request<T>(method: string, path: string, body?: unknown): Promise<T> {
    const controller = new AbortController();
    const timer = setTimeout(() => controller.abort(), DEFAULT_TIMEOUT);

    try {
      const res = await fetch(`${this.baseUrl}${path}`, {
        method,
        headers: body ? { "Content-Type": "application/json" } : undefined,
        body: body ? JSON.stringify(body) : undefined,
        signal: controller.signal,
      });

      if (!res.ok) {
        const text = await res.text().catch(() => "");
        throw new Error(`API ${method} ${path} failed: ${res.status} ${text}`);
      }

      return (await res.json()) as T;
    } finally {
      clearTimeout(timer);
    }
  }
}

// ── Response types ──────────────────────────────────────

export interface Issue {
  code: string;
  category: string;
  severity: "critical" | "major" | "minor" | "info";
  message: string;
  element?: string;
  line?: number;
  suggestion: string;
  wcag_criterion?: string;
  kwcag_criterion?: string;
  kwcag_name?: string;
  kwcag_principle?: string;
}

export interface CategoryResult {
  score: number;
  grade: string;
  total_issues: number;
  critical: number;
  major: number;
  minor: number;
  info: number;
  issues: Issue[];
  wcag_level?: string;
}

export interface InspectionResult {
  inspection_id: string;
  url: string;
  status: "running" | "completed" | "error";
  created_at: string;
  completed_at?: string;
  duration_seconds?: number;
  overall_score: number;
  grade: string;
  accessibility_standard?: string;
  categories: {
    html_css: CategoryResult;
    accessibility: CategoryResult;
    seo: CategoryResult;
    performance_security: CategoryResult;
  };
  summary: {
    total_issues: number;
    critical: number;
    major: number;
    minor: number;
    info: number;
  };
}

export interface IssuesResult {
  inspection_id: string;
  total: number;
  filters: Record<string, string | null>;
  issues: Issue[];
}

export interface InspectionsListResult {
  items: Array<{
    inspection_id: string;
    url: string;
    created_at: string;
    overall_score: number;
    grade: string;
    total_issues: number;
  }>;
  total: number;
  page: number;
  limit: number;
  total_pages: number;
}

export interface SiteInspectionResult {
  site_inspection_id: string;
  root_url: string;
  domain: string;
  status: "crawling" | "inspecting" | "completed" | "error";
  created_at: string;
  completed_at?: string;
  config: {
    max_pages: number;
    max_depth: number;
    concurrency: number;
    accessibility_standard: string;
  };
  discovered_pages: Array<{
    url: string;
    depth: number;
    parent_url?: string;
    inspection_id?: string;
    status: string;
    title?: string;
    overall_score?: number;
    grade?: string;
  }>;
  aggregate_scores?: {
    overall_score: number;
    grade: string;
    html_css: number;
    accessibility: number;
    seo: number;
    performance_security: number;
    total_issues: number;
    pages_inspected: number;
    pages_total: number;
  };
}

export interface SiteInspectionsListResult {
  items: Array<{
    site_inspection_id: string;
    root_url: string;
    domain: string;
    status: string;
    created_at: string;
    pages_total: number;
    pages_inspected: number;
    overall_score?: number;
    grade?: string;
  }>;
  total: number;
  page: number;
  limit: number;
  total_pages: number;
}