// The commit box's logic (spec §5.1), kept free of the vscode module so it

// can be tested: signing state from `oxy identity show`, the placeholder

// that shows it, message history, and conflict marker detection.

export interface SigningInfo {

  /** `Name <email>`, or empty without an identity. */

  who: string;

  /** Whether the secret key is in the key directory. */

  secret: boolean;

  /** `change`: every commit is signed; `seal`: changes are sealed at push. */

  mode: "change" | "seal";

}

/** Parse `oxy --plain identity show`; `null` when no identity is configured. */

export function parseIdentityShow(text: string): SigningInfo | null {

  const head = text.match(/^#\s*identity\s+(.+)$/m);

  if (!head) {

    return null;

  }

  const secretLine = text.match(/^\s*secret\s+(.+)$/m)?.[1] ?? "";

  const signingLine = text.match(/^\s*signing\s+(.+)$/m)?.[1] ?? "";

  return {

    who: head[1].trim(),

    secret: /available/.test(secretLine),

    mode: /core\.sign\s*=\s*change/.test(signingLine) ? "change" : "seal",

  };

}

/** A short name for the placeholder: the name without the address. */

function shortName(who: string): string {

  return who.replace(/\s*<[^>]*>\s*$/, "").trim() || who;

}

/** How the next commit will be authenticated, for the commit box. */

export function signingLabel(info: SigningInfo | null | undefined): string {

  if (info === undefined) {

    return "";

  }

  if (info === null) {

    return "⚠ unsigned: no identity (oxy identity create)";

  }

  if (!info.secret) {

    return `⚠ unsigned: the key for ${shortName(info.who)} is missing`;

  }

  return info.mode === "change" ? `✔ signed as ${shortName(info.who)}` : `◈ sealed at push as ${shortName(info.who)}`;

}

/** The commit box placeholder for the current mode. */

export function placeholder(opts: { amend: boolean; resolution: boolean; signing: string }): string {

  const what = opts.amend ? "Amend the last change: new message, or empty to keep it" : opts.resolution ? "Describe the resolution" : "Message";

  const key = opts.amend ? "Ctrl+Enter to amend" : "Ctrl+Enter to commit";

  return `${what} (${key})${opts.signing ? ` · ${opts.signing}` : ""}`;

}

/** Recent commit messages, newest first, without duplicates. */

export class MessageHistory {

  static readonly LIMIT = 30;

  private items: string[];

  constructor(items: readonly string[] = []) {

    this.items = items.filter((m) => m.trim()).slice(0, MessageHistory.LIMIT);

  }

  add(message: string): void {

    const m = message.trim();

    if (!m) {

      return;

    }

    this.items = [m, ...this.items.filter((x) => x !== m)].slice(0, MessageHistory.LIMIT);

  }

  get entries(): readonly string[] {

    return this.items;

  }

}

/**

 * Line numbers (1-based) that open or close a conflict: Oxygen's markers

 * (`<<<<<<< oxy conflict …`) and Git's alike, since both begin with seven

 * angle brackets.

 */

export function conflictMarkerLines(text: string): number[] {

  const out: number[] = [];

  text.split("\n").forEach((l, i) => {

    if (/^(<{7}|>{7})( |\r?$)/.test(l)) {

      out.push(i + 1);

    }

  });

  return out;

}