import fs from "fs/promises"
import path from "path"
import { describe, expect } from "bun:test"
import { Cause, Effect, Exit, Layer } from "effect"
import { FileSystem } from "@opencode-ai/core/filesystem"
import { FSUtil } from "@opencode-ai/core/fs-util"
import { Location } from "@opencode-ai/core/location"
import { Ripgrep } from "@opencode-ai/core/ripgrep"
import { AbsolutePath, RelativePath } from "@opencode-ai/core/schema"
import { location } from "./fixture/location"
import { tmpdir } from "./fixture/tmpdir"
import { it } from "./lib/effect"

const provide = (directory: string) =>
  Effect.provide(
    FileSystem.layer.pipe(
      Layer.provide(
        Layer.mergeAll(
          FSUtil.defaultLayer,
          Ripgrep.defaultLayer,
          Layer.succeed(Location.Service, Location.Service.of(location({ directory: AbsolutePath.make(directory) }))),
        ),
      ),
    ),
  )

const withTmp = <A, E, R>(f: (directory: string) => Effect.Effect<A, E, R>) =>
  Effect.acquireRelease(
    Effect.promise(() => tmpdir()),
    (tmp) => Effect.promise(() => tmp[Symbol.asyncDispose]()),
  ).pipe(Effect.flatMap((tmp) => f(tmp.path)))

describe("FileSystem", () => {
  const expectFail = (exit: Exit.Exit<unknown, unknown>) => {
    expect(Exit.isFailure(exit)).toBe(true)
    if (Exit.isSuccess(exit)) return
    expect(Cause.hasFails(exit.cause)).toBe(true)
    expect(Cause.hasDies(exit.cause)).toBe(false)
  }

  it.live("reads text and binary files", () =>
    withTmp((directory) =>
      Effect.gen(function* () {
        yield* Effect.promise(() => fs.writeFile(path.join(directory, "text.txt"), "hello"))
        yield* Effect.promise(() => fs.writeFile(path.join(directory, "data.bin"), Buffer.from([0, 1, 2])))
        const service = yield* FileSystem.Service
        const text = yield* service.read({ path: RelativePath.make("text.txt") })
        const binary = yield* service.read({ path: RelativePath.make("data.bin") })
        expect(new TextDecoder().decode(text.content)).toBe("hello")
        expect(text.mime).toBe("text/plain")
        expect(binary.content).toEqual(new Uint8Array([0, 1, 2]))
      }).pipe(provide(directory)),
    ),
  )

  it.live("lists direct children", () =>
    withTmp((directory) =>
      Effect.gen(function* () {
        yield* Effect.promise(() => fs.mkdir(path.join(directory, "src")))
        yield* Effect.promise(() => fs.writeFile(path.join(directory, "README.md"), "# Test"))
        const entries = yield* (yield* FileSystem.Service).list()
        expect(entries.map((entry) => ({ path: entry.path, type: entry.type }))).toEqual([
          { path: RelativePath.make("src" + path.sep), type: "directory" },
          { path: RelativePath.make("README.md"), type: "file" },
        ])
      }).pipe(provide(directory)),
    ),
  )

  it.live("fails for missing paths", () =>
    withTmp((directory) =>
      Effect.gen(function* () {
        const exit = yield* (yield* FileSystem.Service)
          .read({ path: RelativePath.make("missing.txt") })
          .pipe(Effect.exit)
        expectFail(exit)
      }).pipe(provide(directory)),
    ),
  )

  it.live("fails for wrong path kinds", () =>
    withTmp((directory) =>
      Effect.gen(function* () {
        yield* Effect.promise(() => fs.mkdir(path.join(directory, "src")))
        yield* Effect.promise(() => fs.writeFile(path.join(directory, "README.md"), "# Test"))
        const service = yield* FileSystem.Service
        expectFail(yield* service.read({ path: RelativePath.make("src") }).pipe(Effect.exit))
        expectFail(yield* service.list({ path: RelativePath.make("README.md") }).pipe(Effect.exit))
      }).pipe(provide(directory)),
    ),
  )

  it.live("fails for lexical and symlink escapes", () =>
    withTmp((directory) =>
      Effect.gen(function* () {
        const outside = path.join(directory, "..", "outside.txt")
        yield* Effect.promise(() => fs.writeFile(outside, "outside"))
        yield* Effect.promise(() => fs.symlink(outside, path.join(directory, "linked.txt")))
        const service = yield* FileSystem.Service
        expectFail(yield* service.read({ path: RelativePath.make("../outside.txt") }).pipe(Effect.exit))
        expectFail(yield* service.read({ path: RelativePath.make("linked.txt") }).pipe(Effect.exit))
        yield* Effect.promise(() => fs.rm(outside))
      }).pipe(provide(directory)),
    ),
  )
})