import { assertEquals } from "@std/assert";
import type { SystemMessage, Tool } from "@earendil-works/pi-ai";
import type { ConversationId, EntryId, EntryRecord } from "@earendil-works/pi-durable";
import { withDom } from "@berry/util/dom.ts";

const record = (id: number, patch: Partial<SystemMessage>): EntryRecord => ({
  id: id as EntryId,
  conversationId: 1 as ConversationId,
  kind: "pi.system",
  model: [{ role: "system", content: "", timestamp: id, ...patch }],
});

Deno.test("system summaries show net tool changes, not replay churn", async (t) => {
  await withDom(async () => {
    const { transcript } = await import("./transcript.tsx");
    const tool = (name: string, description = name): Tool => ({
      name,
      description,
      parameters: { type: "object", properties: {} },
    });
    const codemode = tool("codemode");
    const read = tool("read");
    const write = tool("write");
    const baseline = record(1, { toolsAdded: [codemode, read, write] });
    const cases: { name: string; patch: Partial<SystemMessage>; expected: string }[] = [
      {
        name: "unchanged remove/re-add pairs disappear but additions remain",
        patch: {
          sections: { berry: "guide", codemode: "catalog" },
          toolsAdded: [tool("subagent"), codemode, read, write],
          toolsRemoved: [codemode, read, write],
        },
        expected: "prompt sections +berry +codemode tools +subagent",
      },
      {
        name: "a changed declaration is shown once",
        patch: {
          toolsAdded: [tool("codemode", "updated"), read, write],
          toolsRemoved: [codemode, read, write],
        },
        expected: "prompt tools +codemode",
      },
      {
        name: "real removals remain visible",
        patch: {
          toolsAdded: [codemode, read],
          toolsRemoved: [codemode, read, write],
        },
        expected: "prompt tools -write",
      },
      {
        name: "reordering alone is not a tool interface change",
        patch: {
          sections: { berry: "guide" },
          toolsAdded: [write, read, codemode],
          toolsRemoved: [codemode, read, write],
        },
        expected: "prompt sections +berry",
      },
    ];
    for (const { name, patch, expected } of cases) {
      await t.step(name, () => {
        const view = transcript();
        try {
          view.update([baseline], {});
          view.update([baseline, record(2, patch)], {});
          const summaries = view.element.querySelectorAll(".system summary");
          assertEquals(summaries[0].textContent, "prompt tools +codemode +read +write");
          assertEquals(summaries[1].textContent, expected);
        } finally {
          view.dispose();
        }
      });
    }
    await t.step("summaries are recalculated when earlier context changes", () => {
      const view = transcript();
      try {
        const updatedTools = [tool("codemode", "updated"), read, write];
        const update = record(2, {
          toolsAdded: updatedTools,
          toolsRemoved: [codemode, read, write],
        });
        view.update([baseline, update], {});
        const summary = view.element.querySelectorAll(".system summary")[1];
        assertEquals(summary.textContent, "prompt tools +codemode");
        view.update([
          record(3, { toolsAdded: updatedTools }),
          update,
        ], {});
        assertEquals(view.element.querySelectorAll(".system summary")[1], summary);
        assertEquals(summary.textContent, "prompt");
      } finally {
        view.dispose();
      }
    });
  });
});

Deno.test("section summaries compare the net effect of a reorder's patches", async (t) => {
  await withDom(async () => {
    const { transcript } = await import("./transcript.tsx");
    const sections = { berry: "guide", code: "coding", web: "browsing" };
    const baseline = record(1, { sections });
    const removal = record(2, { sections: { berry: null, code: null, web: null } });
    const cases: { name: string; sections: Record<string, string>; expected: string[] }[] = [
      {
        name: "inserting a section does not report unchanged sections",
        sections: { berry: "guide", code: "coding", code_project: "project", web: "browsing" },
        expected: ["+code_project"],
      },
      {
        name: "changed values and real removals survive replay churn",
        sections: { code: "updated coding", berry: "guide" },
        expected: ["code", "-web"],
      },
      {
        name: "reordering alone does not report content changes",
        sections: { web: "browsing", code: "coding", berry: "guide" },
        expected: [],
      },
    ];
    for (const { name, sections, expected } of cases) {
      await t.step(name, () => {
        const view = transcript();
        try {
          view.update([baseline, removal, record(3, { timestamp: 2, sections })], {});
          const summaries = view.element.querySelectorAll(".system summary");
          assertEquals(summaries.length, 2);
          assertEquals(
            Array.from(summaries[1].querySelectorAll(".system-name"), (name) => name.textContent),
            expected,
          );
        } finally {
          view.dispose();
        }
      });
    }
    await t.step("split delivery and rewinds update the same summary and its expanded body", () => {
      const view = transcript();
      try {
        const addition = record(3, {
          timestamp: 2,
          sections: { ...sections, code_project: "project" },
        });
        view.update([baseline, removal], {});
        const details = view.element.querySelectorAll<HTMLDetailsElement>(".system")[1];
        const summary = details.querySelector("summary")!;
        details.open = true;
        details.dispatchEvent(new Event("toggle"));
        view.update([baseline, removal, addition], {});
        assertEquals(view.element.querySelectorAll(".system").length, 2);
        assertEquals(details.querySelector("summary"), summary);
        assertEquals(summary.textContent, "prompt sections +code_project");
        assertEquals(Array.from(details.querySelectorAll("pre"), (pre) => pre.textContent), [
          "guide",
          "coding",
          "browsing",
          "project",
        ]);
        assertEquals(details.open, true);

        view.update([baseline, removal], {});
        assertEquals(summary.textContent, "prompt sections -berry -code -web");
        assertEquals(details.querySelectorAll("pre").length, 0);

        view.update([
          record(4, { sections: { ...sections, code_project: "project" } }),
          removal,
          addition,
        ], {});
        assertEquals(details.querySelector("summary"), summary);
        assertEquals(summary.textContent, "prompt");
      } finally {
        view.dispose();
      }
    });
    await t.step("an intervening message prevents unrelated changes from cancelling out", () => {
      const view = transcript();
      try {
        const user: EntryRecord = {
          id: 3 as EntryId,
          conversationId: 1 as ConversationId,
          kind: "pi.user",
          model: [{ role: "user", content: "continue", timestamp: 2 }],
        };
        view.update([baseline, removal, user, record(4, { timestamp: 2, sections })], {});
        assertEquals(
          Array.from(view.element.querySelectorAll(".system summary"), (node) => node.textContent),
          [
            "prompt sections +berry +code +web",
            "prompt sections -berry -code -web",
            "prompt sections +berry +code +web",
          ],
        );
      } finally {
        view.dispose();
      }
    });
  });
});