import { describe, expect, it } from "vitest";
import { importSillyTavernPreset } from "../src/preset/importer.js";
import { PRESET_HISTORY_MARK } from "../src/preset/assembler.js";
import {
  assemblePlayWorkerMessages,
  shapeFramedMessages,
} from "../src/preset/play-frame.js";
import { normalizePseudoHistory } from "../src/preset/pseudo-history.js";
import { buildCaseMessages } from "../src/preset/test-run.js";
import type { PresetChatTurn } from "../src/types/preset.js";

const rawPreset = {
  prompts: [
    { identifier: "main", name: "main", role: "system", content: "MAIN" },
    {
      identifier: "dialogueExamples",
      name: "examples",
      role: "system",
      marker: true,
      content: "",
    },
    {
      identifier: "chatHistory",
      name: "history",
      role: "system",
      marker: true,
      content: "",
    },
  ],
  prompt_order: [
    {
      character_id: 100001,
      order: [
        { identifier: "main", enabled: true },
        { identifier: "dialogueExamples", enabled: true },
        { identifier: "chatHistory", enabled: true },
      ],
    },
  ],
};

function assemble(input: {
  pseudoHistory?: PresetChatTurn[];
  history?: Array<{ role: "user" | "assistant"; content: string }>;
  exampleDialogue?: string;
}) {
  const report = importSillyTavernPreset(rawPreset, { name: "t" });
  const preset = {
    ...report.preset,
    ...(input.pseudoHistory ? { pseudoHistory: input.pseudoHistory } : {}),
  };
  return assemblePlayWorkerMessages({
    systemPrompt: "",
    preset,
    pack: {
      worldBookBefore: [],
      history: input.history ?? [],
      worldBookAfter: [],
      turn: "",
      postTurn: [],
      ...(input.exampleDialogue ? { exampleDialogue: input.exampleDialogue } : {}),
    },
    persona: null,
    charName: "林昭",
  });
}

type Marked = { role: string; content: string };

/** 只取历史区（打了 PRESET_HISTORY_MARK 的那一段）。 */
function historyTurns(messages: Array<Record<string, unknown>>): Marked[] {
  return messages
    .filter((m) => Boolean((m as Record<symbol, unknown>)[PRESET_HISTORY_MARK]))
    .map((m) => ({ role: String(m.role), content: String(m.content) }));
}

describe("预设的假历史：真多轮，不与示例对话混用", () => {
  it("每条假历史各占一条 user / assistant 消息", () => {
    const messages = assemble({
      pseudoHistory: [
        { role: "user", content: "我推开门" },
        { role: "assistant", content: "屋里没有人。" },
      ],
    });
    expect(historyTurns(messages as never)).toEqual([
      { role: "user", content: "我推开门" },
      { role: "assistant", content: "屋里没有人。" },
    ]);
    // 不能伪装成示例对话（system + example_* 的 few-shot）
    expect(messages.some((m) => m.name)).toBe(false);
  });

  it("假历史排在真实历史之前，真实轮次原样保留", () => {
    const messages = assemble({
      pseudoHistory: [
        { role: "user", content: "前情-问" },
        { role: "assistant", content: "前情-答" },
      ],
      history: [
        { role: "user", content: "真-问" },
        { role: "assistant", content: "真-答" },
      ],
    });
    expect(historyTurns(messages as never).map((m) => m.content)).toEqual([
      "前情-问",
      "前情-答",
      "真-问",
      "真-答",
    ]);
  });

  it("正文里的换行是真换行，不会被当成新的一条", () => {
    const messages = assemble({
      pseudoHistory: [
        { role: "assistant", content: "第一段\n\n第二段\nassistant: 这不是新的一条" },
      ],
    });
    const turns = historyTurns(messages as never);
    expect(turns).toHaveLength(1);
    expect(turns[0]!.content).toContain("\n\n");
    expect(turns[0]!.content).toContain("assistant: 这不是新的一条");
  });

  it("合体后的历史区不被 squash 揉成一段", () => {
    const shaped = shapeFramedMessages(
      assemble({
        pseudoHistory: [
          { role: "user", content: "前情-问" },
          { role: "assistant", content: "前情-答" },
        ],
        history: [{ role: "user", content: "真-问" }],
      }),
      "strict",
    );
    const contents = historyTurns(shaped as never).map((m) => m.content);
    expect(contents).toEqual(["前情-问", "前情-答", "真-问"]);
  });

  it("示例对话仍是酒馆的 system + example_* 形状，与假历史并存", () => {
    const messages = assemble({
      pseudoHistory: [{ role: "user", content: "前情" }],
      exampleDialogue: "<START>\nUser: 你好\n林昭: 你也好",
    });
    const examples = messages.filter((m) => m.name?.startsWith("example_"));
    expect(examples.map((m) => m.name)).toEqual([
      "example_user",
      "example_assistant",
    ]);
    expect(examples.every((m) => m.role === "system")).toBe(true);
    // 假历史照旧是真多轮
    expect(historyTurns(messages as never)).toEqual([
      { role: "user", content: "前情" },
    ]);
  });

  it("工作台用例预览走同一条路：预设假历史 + 用例历史 + 本轮输入", () => {
    const report = importSillyTavernPreset(rawPreset, { name: "t" });
    const preset = { ...report.preset, pseudoHistory: [{ role: "user" as const, content: "预设前情" }] };
    const messages = buildCaseMessages(preset, {
      id: "c1",
      name: "c1",
      charName: "林昭",
      charDescription: "",
      worldBook: "",
      userInput: "本轮输入",
      history: [{ role: "assistant", content: "用例前情" }],
    });
    const contents = messages.map((m) => String(m.content));
    const at = (text: string) => contents.findIndex((c) => c.includes(text));
    expect(at("预设前情")).toBeGreaterThanOrEqual(0);
    expect(at("预设前情")).toBeLessThan(at("用例前情"));
    expect(at("用例前情")).toBeLessThan(at("本轮输入"));
  });

  it("非法条目被丢掉，不会变成空消息", () => {
    expect(
      normalizePseudoHistory([
        { role: "user", content: "留着" },
        { role: "system", content: "丢掉" },
        { role: "assistant", content: "   " },
        { role: "assistant" },
        "垃圾",
        null,
      ]),
    ).toEqual([{ role: "user", content: "留着" }]);
    expect(normalizePseudoHistory("user: 我")).toEqual([]);
  });
});