import { describe, expect } from "bun:test"
import { $ } from "bun"
import fs from "fs/promises"
import path from "path"
import { Effect } from "effect"
import { LayerNode } from "@opencode-ai/util/effect/layer-node"
import { Git } from "@opencode-ai/core/git"
import { AbsolutePath, RelativePath } from "@opencode-ai/core/schema"
import { branch, commit, initRepo, read, withRemote } from "./fixture/git"
import { tmpdir } from "./fixture/tmpdir"
import { testEffect } from "./lib/effect"

const it = testEffect(LayerNode.compile(Git.node))

describe("Git", () => {
  it.live("discovers repository metadata without a work tree", () =>
    Effect.gen(function* () {
      const root = yield* Effect.acquireRelease(
        Effect.promise(() => tmpdir()),
        (dir) => Effect.promise(() => dir[Symbol.asyncDispose]()),
      )
      yield* Effect.promise(async () => {
        await initRepo(root.path)
        await $`git config core.bare true`.cwd(root.path).quiet()
      })
      const directory = AbsolutePath.make(yield* Effect.promise(() => fs.realpath(root.path)))
      const git = yield* Git.Service
      const repository = yield* git.repo.discover(directory)

      expect(repository?.worktree).toBe(directory)
      expect(repository?.gitDirectory).toBe(AbsolutePath.make(path.join(directory, ".git")))
      expect(repository?.commonDirectory).toBe(repository?.gitDirectory)
    }),
  )

  it.live("clones a remote and reads checkout metadata", () =>
    withRemote((fixture) =>
      Effect.gen(function* () {
        const git = yield* Git.Service
        const target = AbsolutePath.make(path.join(fixture.root, "checkout"))
        const repository = yield* git.repo.clone({ remote: fixture.remote, directory: target })

        expect(yield* git.remote.get(repository)).toBe(fixture.remote)
        expect(yield* git.history.head(repository)).toBeString()
        expect(yield* git.history.branch(repository)).toBe("main")
        expect(yield* git.history.defaultRemoteBranch(repository)).toBe("main")
        expect(repository.worktree).toBe(target)
        expect(repository.gitDirectory).toBe(AbsolutePath.make(path.join(target, ".git")))
        expect(repository.commonDirectory).toBe(repository.gitDirectory)
        expect(yield* read(path.join(target, "README.md"))).toBe("one\n")
      }),
    ),
  )

  it.live("fetches, checks out, and resets remote changes", () =>
    withRemote((fixture) =>
      Effect.gen(function* () {
        const git = yield* Git.Service
        const target = AbsolutePath.make(path.join(fixture.root, "checkout"))
        const repository = yield* git.repo.clone({ remote: fixture.remote, directory: target })

        yield* Effect.promise(() => commit(fixture.source, "two\n", "second"))
        yield* git.sync.fetchRemotes(repository)
        yield* git.sync.resetHard(repository, "origin/main")
        expect(yield* read(path.join(target, "README.md"))).toBe("two\n")

        yield* Effect.promise(() => branch(fixture.source, "feature/docs", "feature\n"))
        yield* git.sync.fetchBranch(repository, { branch: "feature/docs" })
        yield* git.sync.checkoutRemoteBranch(repository, { branch: "feature/docs" })
        yield* git.sync.resetHard(repository, "origin/feature/docs")
        expect(yield* git.history.branch(repository)).toBe("feature/docs")
        expect(yield* read(path.join(target, "README.md"))).toBe("feature\n")
      }),
    ),
  )
})

describe("Git worktrees", () => {
  it.live("creates, lists, and removes linked worktrees", () =>
    Effect.gen(function* () {
      const root = yield* Effect.acquireRelease(
        Effect.promise(() => tmpdir()),
        (dir) => Effect.promise(() => dir[Symbol.asyncDispose]()),
      )
      yield* Effect.promise(() => initRepo(root.path))
      const directory = AbsolutePath.make(yield* Effect.promise(() => fs.realpath(root.path)))
      const worktree = AbsolutePath.make(`${root.path}-git-worktree`)
      yield* Effect.addFinalizer(() => Effect.promise(() => fs.rm(worktree, { recursive: true, force: true })))
      const git = yield* Git.Service
      const repo = yield* git.repo.discover(directory)
      if (!repo) throw new Error("Repository not found")

      yield* git.worktree.create({ repository: repo, directory: worktree })

      expect((yield* git.worktree.list(repo)).some((entry) => entry.directory.endsWith("-git-worktree"))).toBe(true)
      const linked = yield* git.repo.discover(worktree)
      expect(linked?.worktree).toBe(AbsolutePath.make(yield* Effect.promise(() => fs.realpath(worktree))))
      expect(linked?.commonDirectory).toBe(repo.commonDirectory)
      expect(linked?.gitDirectory).not.toBe(repo.gitDirectory)
      if (!linked) throw new Error("Linked worktree not found")
      yield* git.worktree.remove({ repository: linked, directory: worktree, force: false })
      expect((yield* git.worktree.list(repo)).some((entry) => entry.directory.endsWith("-git-worktree"))).toBe(false)
    }),
  )
})

describe("Git trees", () => {
  ;[0, 1, 128].forEach((exitCode) => {
    it.live(`refresh handles check-ignore exit ${exitCode}`, () =>
      Effect.gen(function* () {
        const root = yield* Effect.acquireRelease(
          Effect.promise(() => tmpdir()),
          (dir) => Effect.promise(() => dir[Symbol.asyncDispose]()),
        )
        const project = path.join(root.path, "project")
        const paths = ["scope/allowed.txt", "scope/ignored name.txt"].map((file) => RelativePath.make(file))
        yield* Effect.promise(async () => {
          await fs.mkdir(path.join(project, "scope"), { recursive: true })
          await initRepo(project)
          await Promise.all(paths.map((file) => Bun.write(path.join(project, file), "one\n")))
          await $`git add .`.cwd(project).quiet()
          await $`git commit -m initial`.cwd(project).quiet()
        })
        const git = yield* Git.Service
        const source = yield* git.repo.discover(AbsolutePath.make(project))
        if (!source) throw new Error("Repository not found")
        const repository = yield* git.repo.create({
          worktree: source.worktree,
          gitDirectory: AbsolutePath.make(path.join(root.path, "storage")),
          seed: source,
        })
        const before = yield* git.tree.write(repository)
        yield* Effect.promise(async () => {
          await Promise.all(paths.map((file) => Bun.write(path.join(project, file), "two\n")))
          await Bun.write(path.join(source.gitDirectory, "info", "exclude"), exitCode === 0 ? `${paths[1]}\n` : "")
          if (exitCode === 128) await Bun.write(path.join(source.gitDirectory, "config"), "[broken\n")
          const result =
            await $`git --git-dir ${source.gitDirectory} --work-tree ${source.worktree} check-ignore --no-index --stdin -z < ${Buffer.from(paths.join("\0") + "\0")}`
              .cwd(project)
              .quiet()
              .nothrow()
          expect(result.exitCode).toBe(exitCode)
        })
        const refresh = git.index.refresh({ repository, scope: RelativePath.make("scope"), ignores: source })
        if (exitCode === 128) {
          const error = yield* refresh.pipe(Effect.flip)
          expect(error).toBeInstanceOf(Git.OperationError)
          expect(error.message).toContain("bad config line")
          expect(yield* git.tree.write(repository)).toBe(before)
          expect(
            yield* git.index.refresh({ repository, scope: RelativePath.make("missing"), ignores: source }),
          ).toEqual({ skipped: [] })
          return
        }
        expect(yield* git.index.ignored({ repository: source, paths })).toEqual(
          new Set(exitCode === 0 ? [paths[1]] : []),
        )
        expect(yield* refresh).toEqual({ skipped: [] })
        const after = yield* git.tree.write(repository)
        expect((yield* git.tree.diff({ repository, from: before, to: after })).map((file) => file.status)).toEqual([
          "modified",
          exitCode === 0 ? "deleted" : "modified",
        ])
      }),
    )
  })

  it.live("lists both sides of a rename as separate file changes", () =>
    Effect.gen(function* () {
      const root = yield* Effect.acquireRelease(
        Effect.promise(() => tmpdir()),
        (dir) => Effect.promise(() => dir[Symbol.asyncDispose]()),
      )
      yield* Effect.promise(async () => {
        await initRepo(root.path)
        await $`git config diff.renames true`.cwd(root.path).quiet()
        await Bun.write(path.join(root.path, "old name.txt"), "Preserve this content.\n")
      })
      const git = yield* Git.Service
      const repository = yield* git.repo.discover(AbsolutePath.make(root.path))
      if (!repository) throw new Error("Repository not found")
      const before = yield* git.tree.capture({ repository, scopes: [RelativePath.make(".")] })
      yield* Effect.promise(() => fs.rename(path.join(root.path, "old name.txt"), path.join(root.path, "new name.txt")))
      const after = yield* git.tree.capture({ repository, scopes: [RelativePath.make(".")] })

      expect(yield* git.tree.files({ repository, from: before, to: after })).toEqual([
        RelativePath.make("new name.txt"),
        RelativePath.make("old name.txt"),
      ])
      expect(
        (yield* git.tree.diff({ repository, from: before, to: after })).map((file) => [file.file, file.status]),
      ).toEqual([
        ["new name.txt", "added"],
        ["old name.txt", "deleted"],
      ])
    }),
  )

  it.live("captures, compares, previews, and restores scoped trees", () =>
    Effect.gen(function* () {
      const root = yield* Effect.acquireRelease(
        Effect.promise(() => tmpdir()),
        (dir) => Effect.promise(() => dir[Symbol.asyncDispose]()),
      )
      yield* Effect.promise(async () => {
        await initRepo(root.path)
        await fs.mkdir(path.join(root.path, "scope"))
        await fs.writeFile(path.join(root.path, "scope", "tracked.txt"), "one\n")
        await fs.writeFile(path.join(root.path, "outside.txt"), "outside\n")
        await $`git add .`.cwd(root.path).quiet()
        await $`git commit -m initial`.cwd(root.path).quiet()
      })
      const git = yield* Git.Service
      const source = yield* git.repo.discover(AbsolutePath.make(root.path))
      if (!source) throw new Error("Repository not found")
      const storage = AbsolutePath.make(path.join(root.path, ".snapshot storage"))
      const repository = yield* git.repo.create({ worktree: source.worktree, gitDirectory: storage, seed: source })
      yield* Effect.promise(() => $`git --git-dir ${storage} config --add include.path first.gitconfig`.quiet())
      yield* Effect.promise(() => $`git --git-dir ${storage} config --add include.path second.gitconfig`.quiet())
      yield* Effect.promise(() => $`git --git-dir ${storage} config core.autocrlf true`.quiet())
      yield* git.repo.create({ worktree: source.worktree, gitDirectory: storage, seed: source })
      expect(
        yield* Effect.promise(() => $`git --git-dir ${storage} config --local --includes core.autocrlf`.text()),
      ).toBe("false\n")
      expect(
        (yield* Effect.promise(() => fs.readFile(path.join(storage, "config"), "utf8"))).match(/opencode\.gitconfig/g),
      ).toHaveLength(1)
      expect(
        yield* Effect.promise(() => $`git --git-dir ${storage} config --local --get-all include.path`.text()),
      ).toBe("opencode.gitconfig\nfirst.gitconfig\nsecond.gitconfig\n")
      yield* git.index.refresh({ repository, scope: RelativePath.make("scope") })
      const before = yield* git.tree.write(repository)

      yield* Effect.promise(async () => {
        await fs.writeFile(path.join(root.path, "scope", "tracked.txt"), "two\n")
        await fs.writeFile(path.join(root.path, "scope", "added.txt"), "added\n")
        await fs.writeFile(path.join(root.path, "outside.txt"), "changed outside\n")
      })
      yield* git.index.refresh({ repository, scope: RelativePath.make("scope") })
      const after = yield* git.tree.write(repository)

      expect(yield* git.tree.files({ repository, from: before, to: after })).toEqual([
        RelativePath.make("scope/added.txt"),
        RelativePath.make("scope/tracked.txt"),
      ])
      const diffs = yield* git.tree.diff({ repository, from: before, to: after, context: 1 })
      expect(diffs.map((item) => [item.file, item.status])).toEqual([
        [RelativePath.make("scope/added.txt"), "added"],
        [RelativePath.make("scope/tracked.txt"), "modified"],
      ])

      const files = new Map([[RelativePath.make("scope/tracked.txt"), before]])
      yield* git.tree.restore({ repository, files })
      expect(yield* read(path.join(root.path, "scope", "tracked.txt"))).toBe("one\n")
      expect(yield* read(path.join(root.path, "scope", "added.txt"))).toBe("added\n")
      expect(yield* read(path.join(root.path, "outside.txt"))).toBe("changed outside\n")
    }),
  )
})