/**
 * @file Client calls for the better-conflicts and history-rewrite surface
 * (server/lib/git-conflicts.js, server/lib/git-rewrite.js): the merge editor's
 * stage read and save, the reflog, remotes, the rewrite plans, and the rewrite
 * / remote writes — each a POST /git/<action> like `api.lanes.gitAction`. Kept
 * out of api.ts so its own surface stays in one file. Every write fires the
 * shared `agenthub:git-changed` event once (`emitGitChanged`, gitChanged.ts),
 * as `api.lanes.gitAction` does, so every open git view reads again.
 * @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
 */

import { gitUrl, request, type GitTarget } from "./api";
import { emitGitChanged } from "./gitChanged";

/** One conflicted file's three sides and the working file it saves over. */
export interface ConflictSides {
  available: boolean;
  path: string;
  operation: "merge" | "cherry-pick" | "revert" | "rebase" | null;
  branch: string | null;
  incoming: { sha: string; short: string; subject: string } | null;
  base: string | null;
  ours: string | null;
  theirs: string | null;
  working: string | null;
  sha: string | null;
  usable: boolean;
  binary: boolean;
  tooBig: boolean;
}

export interface ReflogEntry {
  index: number;
  selector: string;
  sha: string;
  short: string;
  action: string;
  message: string;
  time: number | null;
  subject: string;
}

export interface GitRemote {
  name: string;
  url: string;
  pushUrl: string;
  defaultBranch: string | null;
  /** Its fetched remote-tracking branches (every one, a local copy or not). */
  branches?: string[];
}

export interface PlanCommit {
  sha: string;
  short: string;
  subject: string;
  message: string;
  pushed: boolean;
}

interface PlanCommon {
  available: boolean;
  head: string;
  branch: string | null;
  subdir: boolean;
  operation: string | null;
  dirty: boolean;
}
export interface RebasePlan extends PlanCommon {
  kind: "rebase";
  onto: string;
  commits: PlanCommit[];
  behind: number;
  pushed: number;
}
export interface InteractivePlan extends PlanCommon {
  kind: "interactive";
  base: string;
  merges: boolean;
  commits: PlanCommit[];
  pushed: number;
}
export interface ResetPlan extends PlanCommon {
  kind: "reset";
  target: string;
  related: boolean;
  dropped: number;
  added: number;
  pushed: number;
}
export interface PushPlan extends PlanCommon {
  kind: "push";
  remote: string;
  remoteBranch: string;
  remoteSha: string | null;
  ahead: number;
  behind: number;
  protected: boolean;
  allowed: boolean;
}

export type TodoAction = "pick" | "reword" | "squash" | "fixup" | "drop";
export interface TodoEntry {
  sha: string;
  action: TodoAction;
  message?: string;
}
export type ResetMode = "soft" | "mixed" | "keep" | "hard";

export type RewriteAction =
  | "rebase"
  | "rebase-continue"
  | "rebase-skip"
  | "rebase-abort"
  | "rebase-interactive"
  | "reset"
  | "undo-rewrite"
  | "force-push"
  | "remote-branch-delete"
  | "remote-add"
  | "remote-rename"
  | "remote-remove"
  | "conflict-save";

export interface RewriteResult {
  action: string;
  ok: true;
  output: string;
  before?: string;
  after?: string | null;
  conflicts?: string[];
  stopped?: boolean;
  needsForcePush?: boolean;
  resolved?: boolean;
}

export const gitRewrite = {
  conflict: (t: GitTarget, path: string) =>
    request<ConflictSides>(gitUrl(t, "/conflict", new URLSearchParams({ path }))),
  reflog: (t: GitTarget, opts: { ref?: string; skip?: number; limit?: number } = {}) => {
    const q = new URLSearchParams();
    if (opts.ref) q.set("ref", opts.ref);
    if (opts.skip) q.set("skip", String(opts.skip));
    if (opts.limit) q.set("limit", String(opts.limit));
    return request<{ available: boolean; ref?: string; entries: ReflogEntry[]; more: boolean }>(
      gitUrl(t, "/reflog", q)
    );
  },
  remotes: (t: GitTarget) =>
    request<{ available: boolean; remotes: GitRemote[] }>(gitUrl(t, "/remotes")),
  planRebase: (t: GitTarget, onto: string) =>
    request<RebasePlan>(gitUrl(t, "/rewrite-plan", new URLSearchParams({ kind: "rebase", onto }))),
  planInteractive: (t: GitTarget, base?: string) =>
    request<InteractivePlan>(
      gitUrl(
        t,
        "/rewrite-plan",
        new URLSearchParams(base ? { kind: "interactive", base } : { kind: "interactive" })
      )
    ),
  planReset: (t: GitTarget, target: string) =>
    request<ResetPlan>(gitUrl(t, "/rewrite-plan", new URLSearchParams({ kind: "reset", target }))),
  planPush: (t: GitTarget) =>
    request<PushPlan>(gitUrl(t, "/rewrite-plan", new URLSearchParams({ kind: "push" }))),
  /** POST /git/<action>; fires `agenthub:git-changed` once after it answers (ok or not). */
  run: async (t: GitTarget, action: RewriteAction, body: Record<string, unknown> = {}) => {
    try {
      return await request<RewriteResult>(gitUrl(t, `/${action}`), {
        method: "POST",
        body: JSON.stringify(body),
      });
    } finally {
      emitGitChanged(typeof t === "number" ? t : t.lane, action);
    }
  },
};

/** The error message of a failed call, for an inline alert. */
export function errText(e: unknown): string {
  return e instanceof Error ? e.message : String(e);
}

/** The error code of a failed call (`ApiError.code` / `.status` shape). */
export function errCode(e: unknown): string | undefined {
  const c = (e as { code?: unknown })?.code;
  return typeof c === "string" ? c : undefined;
}