import type { ServiceProvider } from "./types.js";

/**
 * GitHub Gist service provider
 *
 * Users prove ownership by creating a public gist containing their DID.
 * The gist URL is used as the claim URI.
 */
const github: ServiceProvider = {
  id: "github",
  name: "GitHub",
  homepage: "https://github.com",

  // Match GitHub Gist URLs: https://gist.github.com/username/gistid
  reUri: /^https:\/\/gist\.github\.com\/([^/]+)\/([a-f0-9]+)\/?$/,

  isAmbiguous: false,

  ui: {
    description: "Link via a public gist",
    icon: "github",
    inputLabel: "Gist URL",
    inputPlaceholder: "https://gist.github.com/username/abc123...",
    instructions: [
      "Go to [gist.github.com](https://gist.github.com) and create a new gist",
      "Name the file `keytrace.json` (or `keytrace.md` or `proof.md`)",
      "Paste the verification content below into the file",
      "Make sure the gist is **public**, then save it",
      "Copy the gist URL and paste it below",
    ],
    proofTemplate: '{\n  "did": "{did}"\n}',
  },

  processURI(uri, match) {
    const [, username, gistId] = match;

    return {
      profile: {
        display: `@${username}`,
        uri: `https://github.com/${username}`,
      },
      proof: {
        request: {
          uri: `https://api.github.com/gists/${gistId}`,
          fetcher: "http",
          format: "json",
          options: {
            headers: {
              Accept: "application/vnd.github.v3+json",
            },
          },
        },
        target: [
          // Check keytrace.json file content
          {
            path: ["files", "keytrace.json", "content"],
            relation: "contains",
            format: "text",
          },
          // Check proof.md file content
          {
            path: ["files", "proof.md", "content"],
            relation: "contains",
            format: "text",
          },
          // Check keytrace.md file content
          {
            path: ["files", "keytrace.md", "content"],
            relation: "contains",
            format: "text",
          },
          // Check openpgp.md for backwards compatibility with Keyoxide
          {
            path: ["files", "openpgp.md", "content"],
            relation: "contains",
            format: "text",
          },
          // Check gist description
          { path: ["description"], relation: "contains", format: "text" },
        ],
      },
    };
  },

  postprocess(data, match) {
    const [, username] = match;
    const gist = data as { owner?: { avatar_url?: string; login?: string } };

    return {
      subject: gist.owner?.login ?? username,
      avatarUrl: gist.owner?.avatar_url,
      profileUrl: `https://github.com/${gist.owner?.login ?? username}`,
    };
  },

  getProofText(did) {
    return `I'm linking my keytrace.dev: ${did}`;
  },

  getProofLocation() {
    return `Create a public gist with a file named keytrace.json, keytrace.md, or proof.md containing the proof text`;
  },

  getRecommendations(data) {
    const gist = data as { files?: Record<string, unknown> };
    if (!gist.files) return [];

    const actualFiles = Object.keys(gist.files);
    const expectedFiles = ["keytrace.json", "proof.md", "keytrace.md", "openpgp.md"];
    const foundExpected = expectedFiles.filter((f) => actualFiles.includes(f));

    if (foundExpected.length === 0) {
      const fileList = actualFiles.length > 0 ? `Found: ${actualFiles.join(", ")}` : "The gist appears to be empty";
      return [`No recognized proof file found (expected keytrace.json, proof.md, or keytrace.md).<br /> ${fileList}`];
    }

    return [];
  },

  tests: [
    { uri: "https://gist.github.com/alice/abc123def456", shouldMatch: true },
    { uri: "https://gist.github.com/alice/abc123def456/", shouldMatch: true },
    { uri: "https://github.com/alice", shouldMatch: false },
    { uri: "https://gist.gitlab.com/alice/abc123", shouldMatch: false },
  ],
};

export default github;