import fs from "node:fs";
import { chmod, mkdir, rm, symlink, writeFile } from "node:fs/promises";
import { dirname, join } from "node:path";

import { add, commit, init } from "isomorphic-git";
import { describe, expect, it } from "vitest";

import { createTestTempDirectory } from "../../fixtures/temporaryDirectory.js";

import { normalizeHistoricalSourceParseFailures } from "../../../src/application/ReferenceSourceImport.js";
import { importReferenceSource } from "../../support/referenceSourceResourceScope.js";
import {
  parseReferenceSourceEntries,
  projectReferenceSourceEntryFailure,
} from "../../../src/application/ReferenceSourceImportEntries.js";
import type { ReferenceSourceRead } from "../../../src/reference/ReferenceSourceReaderTypes.js";
import { createHistoricalSourceManifest } from "../../../src/domain/referenceSourceGraph.js";

const fixture = async (parent: string, name: string): Promise<string> => {
  const root = join(parent, name);
  await mkdir(join(root, "src"), { recursive: true });
  await Promise.all([
    writeFile(join(root, "src", "main.ts"), 'import "./dep";\n'),
    writeFile(join(root, "src", "dep.ts"), "export const value = 1;\n"),
    writeFile(join(root, "src", "broken.ts"), "const = ;\n"),
    writeFile(join(root, ".env"), "SECRET_SENTINEL=do-not-record\n"),
    writeFile(join(root, "package.json"), '{"name":"fixture"}\n'),
  ]);
  return root;
};

const importTree = (
  root: string,
  signal?: AbortSignal,
  secretPatterns: readonly string[] = [".env", ".env.*"],
) =>
  importReferenceSource({
    root,
    caller: "reference-import-test",
    policy: {
      secretPatterns,
    },
    ...(signal === undefined ? {} : { signal }),
  });

describe("reference source import projections", () => {
  it("deduplicates exact parse failures without collapsing distinct reasons", () => {
    const malformed = {
      path: "src/main.ts",
      parser: "babel",
      reason: "Malformed input",
    };
    const unexpected = {
      path: "src/main.ts",
      parser: "babel",
      reason: "Unexpected token",
    };

    expect(
      normalizeHistoricalSourceParseFailures([
        unexpected,
        malformed,
        unexpected,
      ]),
    ).toEqual([malformed, unexpected]);
  });

  it("retains entry failure diagnostics alongside recovery guidance", () => {
    for (const [kind, code] of [
      ["directory", "io"],
      ["symlink", "io"],
      ["file", "io"],
      ["file", "cancelled"],
      ["unknown", "unsupported"],
    ] as const) {
      const message = projectReferenceSourceEntryFailure({
        status: "failed",
        path: "safe/path",
        kind,
        code,
        message: "Observed entry failure at /owned/fixture/path",
      });
      expect(message).toContain(
        "Observed entry failure at /owned/fixture/path",
      );
      expect(message).toMatch(/Check|try again|when ready|Exclude/u);
    }
  });
});

describe("reference source symlink import", () => {
  it.each([
    { target: "dist", reason: "default-ignored", pattern: "dist/" },
    { target: "generated", reason: "project-ignored", pattern: "generated/" },
    { target: "cache", reason: "caller-excluded", pattern: "cache/" },
  ])(
    "retains links into a $reason directory without importing it",
    async ({ target, reason, pattern }) => {
      const root = await createTestTempDirectory(
        "rea-reference-excluded-links-",
      );
      await mkdir(join(root, target, "nested"), { recursive: true });
      await writeFile(
        join(root, target, "nested", "output.js"),
        "export const generated = true;\n",
      );
      await writeFile(join(root, "source.ts"), "export const value = 1;\n");
      if (reason === "project-ignored")
        await writeFile(join(root, ".gitignore"), `${pattern}\n`);
      await symlink(target, join(root, "alias"));
      await symlink(`${target}/nested/output.js`, join(root, "output-link"));

      const result = await importReferenceSource({
        root,
        caller: "reference-import-test",
        policy: { secretPatterns: [] },
        ...(reason === "caller-excluded" ? { excludePaths: [pattern] } : {}),
      });
      if (!result.ok) throw result.error;
      expect(result.value.inventory_state).toBe("partial");
      expect(result.value.exclusions).toContainEqual({
        path: target,
        entry_kind: "directory",
        reason,
        pattern,
      });
      expect(result.value.entries).toEqual(
        expect.arrayContaining([
          expect.objectContaining({
            path: "source.ts",
            kind: "file",
            content_state: "hashed",
          }),
          expect.objectContaining({
            path: "alias",
            kind: "symlink",
            target,
            target_state: "internal",
          }),
          expect.objectContaining({
            path: "output-link",
            kind: "symlink",
            target: `${target}/nested/output.js`,
            target_state: "internal",
          }),
        ]),
      );
      expect(
        result.value.entries.some(
          ({ path }) => path === target || path.startsWith(`${target}/`),
        ),
      ).toBe(false);
    },
  );

  it("does not treat an excluded file as an excluded directory for a child link", async () => {
    const root = await createTestTempDirectory(
      "rea-reference-excluded-file-link-",
    );
    await writeFile(join(root, "secret.txt"), "secret\n");
    await writeFile(join(root, "source.ts"), "export const value = 1;\n");
    await symlink("secret.txt/child", join(root, "alias"));

    const result = await importReferenceSource({
      root,
      caller: "reference-import-test",
      policy: { secretPatterns: [] },
      excludePaths: ["secret.txt"],
    });
    if (!result.ok) throw new Error(result.error.message);
    expect(result.value.inventory_state).toBe("partial");
    expect(
      result.value.entries.find(({ path }) => path === "alias"),
    ).toMatchObject({
      kind: "symlink",
      target: "secret.txt/child",
      target_state: "missing",
    });
    expect(result.value.exclusions).toContainEqual({
      path: "secret.txt",
      entry_kind: "file",
      reason: "caller-excluded",
      pattern: "secret.txt",
    });
  });

  it("preserves an unreadable target as unknown instead of a synthetic path", () => {
    const read: ReferenceSourceRead = {
      root: "/reference",
      entries: [
        {
          status: "failed",
          kind: "symlink",
          path: "src/link.ts",
          code: "io",
          message: "Symbolic link target could not be read",
        },
      ],
      bytesRead: 0,
      limitations: [],
    };

    const parsed = parseReferenceSourceEntries(read, new Set());
    expect(parsed.entries).toContainEqual(
      expect.objectContaining({
        kind: "symlink",
        path: "src/link.ts",
        target: null,
        target_state: "unreadable",
      }),
    );
  });

  it("retains external symlink targets as local graph diagnostics", async () => {
    const root = await createTestTempDirectory("rea-reference-links-");
    const outside = await createTestTempDirectory("rea-reference-outside-");
    const target = join(outside, "target.js");
    await writeFile(target, "export {};");
    await symlink(target, join(root, "external.js"));

    const imported = await importTree(root);

    if (!imported.ok) throw imported.error;
    expect(imported.value.entries).toContainEqual(
      expect.objectContaining({
        kind: "symlink",
        path: "external.js",
        target,
        target_state: "external",
        limitations: [],
      }),
    );
    expect(imported.value.entries).not.toContainEqual(
      expect.objectContaining({ path: "target.js", kind: "file" }),
    );
  });
});

describe("reference source manifest inventory", () => {
  it("retains manifest, test, generated and language classifications through import", async () => {
    const root = await createTestTempDirectory("rea-reference-classification-");
    const files = [
      ["CMakeLists.txt", "Text", ["documentation", "manifest"]],
      ["src/CMAKELISTS.TXT", "Text", ["documentation", "manifest", "source"]],
      ["CMakeLists.txt.backup", null, ["unknown"]],
      ["Dockerfile.dev.ts", "Dockerfile", ["source"]],
      ["DockerfileGuide.d.mts", "TypeScript", ["generated", "source"]],
      ["DockerfileHelper.py", "Python", ["source"]],
      ["dockerfiles", null, ["unknown"]],
      ["Widget_TeSt.TS", "TypeScript", ["source", "test"]],
      ["parser_spec.rs", "Rust", ["source", "test"]],
      ["main_test_helper.go", "Go", ["source"]],
      ["main_spec.ts.bak", null, ["unknown"]],
      ["tests/main.go", "Go", ["source", "test"]],
      ["out/widget_spec.js", "JavaScript", ["generated", "source", "test"]],
      ["vendor/widget_test.go", "Go", ["source", "test", "vendor"]],
      ["settings_spec.json", "JSON", ["config", "test"]],
      [
        "docs/api/client.ts",
        "TypeScript",
        ["documentation", "generated", "source"],
      ],
      [
        "packages/widget/Docs/API/client.ts",
        "TypeScript",
        ["documentation", "generated", "source"],
      ],
      ["docs/apis/client.ts", "TypeScript", ["documentation", "source"]],
      ["mydocs/api/client.ts", "TypeScript", ["source"]],
      ["docs/manual/api/client.ts", "TypeScript", ["documentation", "source"]],
      ["docs/api.ts", "TypeScript", ["documentation", "source"]],
      ["public/client.ts", "TypeScript", ["generated", "source"]],
      [".github", null, ["config"]],
      [".husky", null, ["config"]],
      [".gitignore", null, ["config"]],
    ] as const;
    await Promise.all(
      files.map(async ([path]) => {
        const target = join(root, path);
        await mkdir(dirname(target), { recursive: true });
        await writeFile(target, "");
      }),
    );

    const result = await importTree(root);
    if (!result.ok) throw result.error;
    expect(result.value.manifests).toEqual([
      "CMakeLists.txt",
      "src/CMAKELISTS.TXT",
    ]);
    const entries = new Map(
      result.value.entries.map((entry) => [entry.path, entry]),
    );
    for (const [path, language, classifications] of files)
      expect(entries.get(path), path).toMatchObject({
        kind: "file",
        language,
        classifications,
      });
    for (const path of ["docs/api", "packages/widget/Docs/API"])
      expect(entries.get(path), path).toMatchObject({
        kind: "directory",
        classifications: ["documentation", "generated"],
      });
  });
});

describe("reference source import behavior", () => {
  // The importer declares no byte ceiling and no entry-count ceiling. Scale
  // independence cannot be asserted as a relationship over a bounded fixture,
  // because a cap above the fixture size would pass unnoticed, so the fixture
  // has to cross any ceiling a future change would plausibly introduce: 5,000
  // entries is well past a round 1,000 or 2,000 cap, and one 4 MiB member is
  // well past a 1 MiB cap.
  //
  // The two boundaries are crossed independently rather than as a cross
  // product. Cycling the sizes over every entry would make a thousand 4 MiB
  // members, which is nearly 4 GiB of fixture and cannot fit a runner's disk.
  // Entry count is crossed by volume, byte size by a single large member.
  it("returns every written entry with complete coverage at any scale", async () => {
    const root = await createTestTempDirectory("rea-reference-scale-");
    const sizes = [0, 1, 4_097, 65_536, 4_194_304];
    const written = Array.from(
      { length: 5_000 },
      (_, index) => `entry-${String(index).padStart(5, "0")}.txt`,
    );
    // Only the first entry of each size takes that size; the remaining 4,995
    // stay one byte each. The fixture is therefore about 4.2 MiB in total
    // while still containing a member far larger than any byte ceiling.
    const sizeFor = (index: number): number => sizes[index] ?? 1;
    await Promise.all(
      written.map((name, index) =>
        writeFile(join(root, name), "a".repeat(sizeFor(index))),
      ),
    );

    const result = await importReferenceSource({
      root,
      caller: "reference-import-test",
      policy: { secretPatterns: [] },
    });

    if (!result.ok) throw result.error;
    // The importer always reports one standing advisory about pathname races,
    // so completeness is asserted per entry rather than globally.
    const limited = result.value.entries.filter(
      (entry) => entry.limitations.length > 0,
    );
    expect(limited.map((entry) => entry.path)).toEqual([]);
    expect(result.value.entries).toHaveLength(written.length);
    expect(new Set(result.value.entries.map((entry) => entry.path))).toEqual(
      new Set(written),
    );
    // Members of every size must still be hashed rather than skipped or
    // truncated, including the 4 MiB member, so each entry is checked against
    // the size it was actually written with.
    for (const [index, size] of sizes.entries()) {
      expect(result.value.entries).toContainEqual(
        expect.objectContaining({
          path: `entry-${String(index).padStart(5, "0")}.txt`,
          kind: "file",
          size,
          content_state: "hashed",
        }),
      );
    }
    // The bulk of the fixture must also survive intact, so a cap on either
    // dimension fails even though only five entries carry a distinct size.
    const bulk = result.value.entries.filter(
      (entry) =>
        Number.parseInt(entry.path.replace("entry-", ""), 10) >= sizes.length,
    );
    expect(bulk).toHaveLength(written.length - sizes.length);
    expect(bulk.every((entry) => "size" in entry && entry.size === 1)).toBe(
      true,
    );
    // `inventory_state` is deliberately not asserted to equal "complete": the
    // importer always reports a standing advisory that Node cannot offer
    // descriptor-relative openat traversal, which forces "partial" on every
    // host. Completeness is proven above at the entry level, where it is
    // actually meaningful.
  });

  it("imports BMP and supplementary filenames in Unicode code point order", async () => {
    const root = await createTestTempDirectory("reference-unicode-");
    try {
      const paths = ["\uE000.ts", "\u{10000}.ts"];
      await Promise.all(
        paths.map((path) =>
          writeFile(join(root, path), "export const value = 1;\n"),
        ),
      );
      const result = await importTree(root);
      if (!result.ok) throw result.error;
      expect(result.value.entries.map(({ path }) => path)).toEqual(paths);
      const repeated = await importTree(root);
      expect(repeated).toEqual(result);
    } finally {
      await rm(root, { recursive: true, force: true });
    }
  });

  it("is relocation-stable, resolves imports, and excludes secrets before capture", async () => {
    const parent = await createTestTempDirectory("rea-reference-import-");
    try {
      const leftRoot = await fixture(parent, "left");
      const rightRoot = await fixture(parent, "right");
      const [left, right] = await Promise.all([
        importTree(leftRoot),
        importTree(rightRoot),
      ]);
      if (!left.ok || !right.ok) throw new Error("expected imports to pass");
      expect(createHistoricalSourceManifest(left.value)).toEqual(
        createHistoricalSourceManifest(right.value),
      );
      expect(left.value.relationships).toContainEqual(
        expect.objectContaining({
          from_path: "src/main.ts",
          to: "src/dep.ts",
          resolution: "internal",
        }),
      );
      expect(left.value.parse_failures).toHaveLength(1);
      expect(left.value.exclusions).toContainEqual({
        path: ".env",
        entry_kind: "file",
        reason: "configured-secret",
        pattern: ".env",
      });
      expect(JSON.stringify(left.value)).not.toContain("SECRET_SENTINEL");
      expect(JSON.stringify(left.value)).not.toContain(leftRoot);
    } finally {
      await rm(parent, { recursive: true, force: true });
    }
  });

  it("imports the caller-selected directory and honors cancellation", async () => {
    const outside = await createTestTempDirectory("rea-reference-outside-");
    try {
      const root = await fixture(outside, "tree");
      expect(await importTree(root)).toMatchObject({ ok: true });
      const controller = new AbortController();
      controller.abort();
      const cancelled = await importTree(root, controller.signal);
      expect(cancelled).toMatchObject({
        ok: false,
        error: { code: "cancelled" },
      });
    } finally {
      await rm(outside, { recursive: true, force: true });
    }
  });

  it("records bounded local Git state without invoking Git", async () => {
    const parent = await createTestTempDirectory("rea-reference-git-");
    try {
      const root = await fixture(parent, "repo");
      await init({ fs, dir: root, defaultBranch: "main" });
      for (const filepath of ["package.json", "src/main.ts", "src/dep.ts"])
        await add({ fs, dir: root, filepath });
      const oid = await commit({
        fs,
        dir: root,
        author: { name: "REA Test", email: "rea@example.invalid" },
        message: "fixture",
      });
      const result = await importTree(root);
      if (!result.ok) throw result.error;
      expect(result.value.vcs).toEqual({ kind: "git", head: oid, dirty: null });
    } finally {
      await rm(parent, { recursive: true, force: true });
    }
  });
});

describe("reference source path selection", () => {
  it("does not omit selected files by secret-like path or filename", async () => {
    const parent = await createTestTempDirectory("rea-reference-selected-");
    try {
      const root = await fixture(parent, "tree");
      const result = await importTree(root, undefined, []);
      if (!result.ok) throw result.error;
      expect(result.value.entries).toContainEqual(
        expect.objectContaining({
          path: ".env",
          kind: "file",
          content_state: "hashed",
        }),
      );
      expect(result.value.exclusions).not.toContainEqual(
        expect.objectContaining({ path: ".env" }),
      );
    } finally {
      await rm(parent, { recursive: true, force: true });
    }
  });
});

describe("reference source rooted module specifiers", () => {
  it("keeps dot-prefixed bare specifiers external while resolving explicit relative paths", async () => {
    const root = await createTestTempDirectory("rea-reference-dot-prefix-");
    await Promise.all([
      writeFile(
        join(root, "main.js"),
        'import ".hidden.js"; import "..pkg.js"; import "./.hidden.js"; require(".hidden.js");\n',
      ),
      writeFile(join(root, ".hidden.js"), "export {};\n"),
      writeFile(join(root, "..pkg.js"), "export {};\n"),
    ]);
    const result = await importTree(root);
    if (!result.ok) throw result.error;
    expect(result.value.relationships).toEqual(
      expect.arrayContaining([
        expect.objectContaining({
          to: ".hidden.js",
          kind: "imports",
          resolution: "external",
        }),
        expect.objectContaining({
          to: "..pkg.js",
          kind: "imports",
          resolution: "external",
        }),
        expect.objectContaining({
          to: ".hidden.js",
          kind: "imports",
          resolution: "internal",
        }),
        expect.objectContaining({
          to: ".hidden.js",
          kind: "requires",
          resolution: "external",
        }),
      ]),
    );
  });

  it("does not rebase an absolute import onto a coincidentally matching source member", async () => {
    const root = await createTestTempDirectory("rea-reference-rooted-");
    await mkdir(join(root, "src", "outside"), { recursive: true });
    await writeFile(
      join(root, "src", "main.js"),
      'import "/outside/dep.js"; import "./outside/dep.js";\n',
    );
    await writeFile(
      join(root, "src", "outside", "dep.js"),
      "export const value = 1;\n",
    );
    const result = await importTree(root);
    if (!result.ok) throw result.error;
    expect(result.value.relationships).toContainEqual({
      from_path: "src/main.js",
      to: "/outside/dep.js",
      kind: "imports",
      resolution: "unresolved",
      parse_state: "parsed",
    });
    expect(result.value.relationships).toContainEqual({
      from_path: "src/main.js",
      to: "src/outside/dep.js",
      kind: "imports",
      resolution: "internal",
      parse_state: "parsed",
    });
  });
});

describe.skipIf(process.platform === "win32")(
  "reference source exclusion provenance",
  () => {
    it("preserves ordered ignore rules and reports each winning rule origin", async () => {
      const root = await createTestTempDirectory(
        "rea-reference-ignore-origin-",
      );
      const directories = [
        "dist",
        "project-parent",
        "caller-parent",
        "node_modules/pkg",
        "empty-ignored",
        "secret-dir",
        "keep-as-dir",
        "link-target",
      ];
      await Promise.all(
        directories.map((path) => mkdir(join(root, path), { recursive: true })),
      );
      const secretChild = join(root, "secret-dir", "unreadable.ts");
      await Promise.all([
        writeFile(
          join(root, ".gitignore"),
          "project.tmp\n*.log\n!keep.log\nproject-parent/\n!project-parent/keep.ts\n!default.log\nempty-ignored/\nkeep-as-dir\n!keep-as-dir/\nlinkdir/\n",
        ),
        writeFile(join(root, "project.tmp"), "project rule\n"),
        writeFile(join(root, "project.log"), "project rule\n"),
        writeFile(join(root, "keep.log"), "later default rule wins\n"),
        writeFile(join(root, "default.log"), "default rule\n"),
        writeFile(join(root, "caller-keep.log"), "caller negation\n"),
        writeFile(join(root, "dist", "output.js"), "generated output\n"),
        writeFile(join(root, "project-parent", "keep.ts"), "parent ignored\n"),
        writeFile(join(root, "caller-parent", "keep.ts"), "caller parent\n"),
        writeFile(join(root, "node_modules/pkg/package.json"), "{}\n"),
        writeFile(join(root, "secret-dir", "unreadable.ts"), "secret\n"),
        writeFile(join(root, "keep-as-dir", "kept.ts"), "re-included\n"),
        writeFile(join(root, "link-target", "source.ts"), "target\n"),
        writeFile(join(root, "selected.ts"), "selected source\n"),
      ]);
      await symlink(join(root, "link-target"), join(root, "linkdir"));

      const canRestrictPermissions =
        process.platform !== "win32" && process.getuid?.() !== 0;
      if (canRestrictPermissions) await chmod(secretChild, 0);

      try {
        const imported = await importReferenceSource({
          root,
          caller: "reference-import-test",
          policy: { secretPatterns: ["project.log", "secret-dir/"] },
          excludePaths: ["caller-parent/", "!selected.ts", "!caller-keep.log"],
        });
        if (!imported.ok) throw imported.error;

        expect(imported.value.exclusions).toEqual(
          expect.arrayContaining([
            {
              path: "project.tmp",
              entry_kind: "file",
              reason: "project-ignored",
              pattern: "project.tmp",
            },
            {
              path: "project.log",
              entry_kind: "file",
              reason: "configured-secret",
              pattern: "project.log",
            },
            {
              path: "keep.log",
              entry_kind: "file",
              reason: "default-ignored",
              pattern: "*.log",
            },
            {
              path: "dist",
              entry_kind: "directory",
              reason: "default-ignored",
              pattern: "dist/",
            },
            {
              path: "node_modules",
              entry_kind: "directory",
              reason: "default-ignored",
              pattern: "node_modules/",
            },
            {
              path: "empty-ignored",
              entry_kind: "directory",
              reason: "project-ignored",
              pattern: "empty-ignored/",
            },
            {
              path: "project-parent",
              entry_kind: "directory",
              reason: "project-ignored",
              pattern: "project-parent/",
            },
            {
              path: "caller-parent",
              entry_kind: "directory",
              reason: "caller-excluded",
              pattern: "caller-parent/",
            },
            {
              path: "secret-dir",
              entry_kind: "directory",
              reason: "configured-secret",
              pattern: "secret-dir/",
            },
          ]),
        );
        expect(imported.value.entries).toContainEqual(
          expect.objectContaining({ path: "selected.ts", kind: "file" }),
        );
        expect(imported.value.entries).toContainEqual(
          expect.objectContaining({ path: "caller-keep.log", kind: "file" }),
        );
        expect(imported.value.entries).toContainEqual(
          expect.objectContaining({
            path: "keep-as-dir/kept.ts",
            kind: "file",
          }),
        );
        expect(imported.value.entries).toContainEqual(
          expect.objectContaining({ path: "linkdir", kind: "symlink" }),
        );
        for (const path of [
          "dist",
          "node_modules",
          "empty-ignored",
          "project-parent",
          "caller-parent",
          "secret-dir",
        ])
          expect(
            imported.value.entries.some(
              (entry) =>
                entry.path === path || entry.path.startsWith(`${path}/`),
            ),
            path,
          ).toBe(false);
        expect(imported.value.exclusions).not.toContainEqual(
          expect.objectContaining({ path: "selected.ts" }),
        );
      } finally {
        if (canRestrictPermissions) await chmod(secretChild, 0o600);
      }
    });
  },
);