// "Resolve in VS Code" (OxygenHub's conflict resolver hands a conflict to

// the extension): vscode://oxygenhub.oxygen/resolve?url=…&bookmark=…&path=…

// Parsing and matching live here, apart from VS Code, so they are tested.

export interface ResolveRequest {

  /** The repository's clone URL on the hub. */

  url: string;

  bookmark: string;

  /** Relative to the repository root. */

  path: string;

}

/** Read a resolve request's query string, or say what is wrong with it. */

export function parseResolveQuery(query: string): ResolveRequest | string {

  const q = new URLSearchParams(query);

  const url = (q.get("url") ?? "").trim();

  const bookmark = (q.get("bookmark") ?? "").trim();

  const path = (q.get("path") ?? "").trim().replace(/^\/+/, "");

  if (!/^https?:\/\/[^\s]+$/.test(url)) {

    return "the link names no repository URL";

  }

  if (!bookmark || /[\s~^:?*[\\]/.test(bookmark) || bookmark.includes("..")) {

    return "the link names no valid bookmark";

  }

  if (!path || path.split("/").some((c) => c === "" || c === "." || c === ".." || c === ".oxy")) {

    return "the link names no valid path";

  }

  return { url, bookmark, path };

}

/** Whether two remote URLs name the same repository (case of the host and a trailing slash aside). */

export function sameRemote(a: string, b: string): boolean {

  const norm = (u: string) => {

    try {

      const x = new URL(u.trim());

      return `${x.protocol}//${x.host.toLowerCase()}${x.pathname.replace(/\/+$/, "").replace(/\.oxy$/, "")}`;

    } catch {

      return u.trim().replace(/\/+$/, "");

    }

  };

  return norm(a) === norm(b);

}

export interface PlanRequest {

  url: string;

  bookmark: string;

  /** `squash` (change into target) or `rebase` (change onto target). */

  kind: "squash" | "rebase";

  change: string;

  target: string;

}

/**

 * A rewrite planned on OxygenHub's swimlanes:

 * vscode://oxygenhub.oxygen/plan?url=…&bookmark=…&kind=…&change=…&target=…

 */

export function parsePlanQuery(query: string): PlanRequest | string {

  const q = new URLSearchParams(query);

  const base = parseResolveQuery(new URLSearchParams({ url: q.get("url") ?? "", bookmark: q.get("bookmark") ?? "", path: "x" }).toString());

  if (typeof base === "string") {

    return base;

  }

  const kind = q.get("kind");

  if (kind !== "squash" && kind !== "rebase") {

    return "the link names no squash or rebase";

  }

  const hex = /^[0-9a-f]{64}$/;

  const change = q.get("change") ?? "";

  const target = q.get("target") ?? "";

  if (!hex.test(change) || !hex.test(target) || change === target) {

    return "the link names no two changes";

  }

  return { url: base.url, bookmark: base.bookmark, kind, change, target };

}