import { mkdtempSync, mkdirSync, writeFileSync, rmSync } from 'node:fs'
import { tmpdir } from 'node:os'
import { resolve } from 'node:path'
import { afterEach, beforeEach, describe, expect, it } from 'vitest'

import { buildBumpFileSet, incVersion } from '../scripts/update-changelog.ts'
import { resolveWorkspaces } from '../scripts/_workspaces.ts'

let tmp: string

beforeEach(() => {
  tmp = mkdtempSync(resolve(tmpdir(), 'uppt-bump-'))
})

afterEach(() => {
  rmSync(tmp, { recursive: true, force: true })
})

function writePackage (relDir: string, contents: Record<string, unknown>, opts: { indent?: string | number, trailingNewline?: string } = {}) {
  const dir = resolve(tmp, relDir)
  mkdirSync(dir, { recursive: true })
  const indent = opts.indent ?? 2
  const trailingNewline = opts.trailingNewline ?? ''
  writeFileSync(resolve(dir, 'package.json'), JSON.stringify(contents, null, indent) + trailingNewline)
}

function sourceOf (pkg: Record<string, unknown>): string {
  return JSON.stringify(pkg, null, 2) + '\n'
}

describe('incVersion', () => {
  it('bumps patch', () => {
    expect(incVersion('1.2.3', 'patch')).toBe('1.2.4')
  })

  it('bumps minor and resets patch', () => {
    expect(incVersion('1.2.3', 'minor')).toBe('1.3.0')
  })

  it('bumps major and resets minor and patch', () => {
    expect(incVersion('1.2.3', 'major')).toBe('2.0.0')
  })

  it('maps a major bump in 0.x.y to the minor slot', () => {
    expect(incVersion('0.2.3', 'major')).toBe('0.3.0')
  })

  it('maps minor and patch bumps in 0.x.y to the patch slot', () => {
    expect(incVersion('0.2.3', 'minor')).toBe('0.2.4')
    expect(incVersion('0.2.3', 'patch')).toBe('0.2.4')
  })

  it('supports 0.0.x versions with the same 0.x.y mapping', () => {
    expect(incVersion('0.0.3', 'major')).toBe('0.1.0')
    expect(incVersion('0.0.3', 'minor')).toBe('0.0.4')
    expect(incVersion('0.0.3', 'patch')).toBe('0.0.4')
  })

  it('throws on a prerelease version', () => {
    expect(() => incVersion('1.2.3-rc.1', 'patch')).toThrowError(/strict "X\.Y\.Z" semver/)
  })

  it('throws on a version with build metadata', () => {
    expect(() => incVersion('1.2.3+sha.abc', 'patch')).toThrowError(/strict "X\.Y\.Z" semver/)
  })

  it('throws on a non-semver string', () => {
    expect(() => incVersion('not-a-version', 'patch')).toThrowError(/strict "X\.Y\.Z" semver/)
  })
})

describe('buildBumpFileSet', () => {
  describe('single-package mode', () => {
    it('rewrites the root package.json with the new version', () => {
      const rootPkg = { name: 'pkg', version: '1.2.3' }
      const files = buildBumpFileSet({
        monorepo: false,
        workspaces: [],
        rootPkg,
        rootPkgSource: sourceOf(rootPkg),
        currentVersion: '1.2.3',
        newVersion: '1.2.4',
      })
      expect(files).toEqual([
        { path: 'package.json', content: `${JSON.stringify({ name: 'pkg', version: '1.2.4' }, null, 2)}\n` },
      ])
    })

    it('preserves other root fields', () => {
      const rootPkg = { name: 'pkg', version: '1.2.3', description: 'hello', private: false }
      const files = buildBumpFileSet({
        monorepo: false,
        workspaces: [],
        rootPkg,
        rootPkgSource: sourceOf(rootPkg),
        currentVersion: '1.2.3',
        newVersion: '1.2.4',
      })
      const written = JSON.parse(files[0]!.content)
      expect(written).toEqual({ name: 'pkg', version: '1.2.4', description: 'hello', private: false })
    })

    it('preserves the existing indentation of the root package.json', () => {
      const rootPkg = { name: 'pkg', version: '1.2.3' }
      const tabSource = '{\n\t"name": "pkg",\n\t"version": "1.2.3"\n}\n'
      const files = buildBumpFileSet({
        monorepo: false,
        workspaces: [],
        rootPkg,
        rootPkgSource: tabSource,
        currentVersion: '1.2.3',
        newVersion: '1.2.4',
      })
      expect(files[0]!.content).toBe('{\n\t"name": "pkg",\n\t"version": "1.2.4"\n}\n')
    })
  })

  describe('monorepo mode', () => {
    it('rewrites every workspace package.json', () => {
      writePackage('packages/a', { name: 'a', version: '1.2.3' })
      writePackage('packages/b', { name: 'b', version: '1.2.3' })
      const workspaces = resolveWorkspaces(tmp, 'packages/*')
      const rootPkg = { name: 'root', private: true }

      const files = buildBumpFileSet({
        monorepo: true,
        workspaces,
        rootPkg,
        rootPkgSource: sourceOf(rootPkg),
        currentVersion: '1.2.3',
        newVersion: '1.2.4',
      })

      const byPath = Object.fromEntries(files.map(f => [f.path, JSON.parse(f.content)]))
      expect(byPath['packages/a/package.json']).toMatchObject({ name: 'a', version: '1.2.4' })
      expect(byPath['packages/b/package.json']).toMatchObject({ name: 'b', version: '1.2.4' })
    })

    it('leaves the root alone when it has no version', () => {
      writePackage('packages/a', { name: 'a', version: '1.2.3' })
      const workspaces = resolveWorkspaces(tmp, 'packages/a')
      const rootPkg = { name: 'root', private: true }

      const files = buildBumpFileSet({
        monorepo: true,
        workspaces,
        rootPkg,
        rootPkgSource: sourceOf(rootPkg),
        currentVersion: '1.2.3',
        newVersion: '1.2.4',
      })

      expect(files.map(f => f.path)).toEqual(['packages/a/package.json'])
    })

    it('bumps the root when its version equals the current lockstep', () => {
      writePackage('packages/a', { name: 'a', version: '1.2.3' })
      const workspaces = resolveWorkspaces(tmp, 'packages/a')
      const rootPkg = { name: 'root', version: '1.2.3', private: true }

      const files = buildBumpFileSet({
        monorepo: true,
        workspaces,
        rootPkg,
        rootPkgSource: sourceOf(rootPkg),
        currentVersion: '1.2.3',
        newVersion: '1.2.4',
      })

      const rootFile = files.find(f => f.path === 'package.json')!
      expect(JSON.parse(rootFile.content)).toMatchObject({ name: 'root', version: '1.2.4', private: true })
    })

    it('leaves the root alone when its version differs from the lockstep', () => {
      writePackage('packages/a', { name: 'a', version: '1.2.3' })
      const workspaces = resolveWorkspaces(tmp, 'packages/a')
      const rootPkg = { name: 'root', version: '0.0.0', private: true }

      const files = buildBumpFileSet({
        monorepo: true,
        workspaces,
        rootPkg,
        rootPkgSource: sourceOf(rootPkg),
        currentVersion: '1.2.3',
        newVersion: '1.2.4',
      })

      expect(files.map(f => f.path)).toEqual(['packages/a/package.json'])
    })

    it('preserves unrelated workspace fields', () => {
      writePackage('packages/a', { name: 'a', version: '1.2.3', dependencies: { foo: 'workspace:^' } })
      const workspaces = resolveWorkspaces(tmp, 'packages/a')
      const rootPkg = { name: 'root', private: true }

      const files = buildBumpFileSet({
        monorepo: true,
        workspaces,
        rootPkg,
        rootPkgSource: sourceOf(rootPkg),
        currentVersion: '1.2.3',
        newVersion: '1.2.4',
      })

      expect(JSON.parse(files[0]!.content)).toEqual({
        name: 'a',
        version: '1.2.4',
        dependencies: { foo: 'workspace:^' },
      })
    })

    it('preserves each workspace package.json indentation independently', () => {
      writePackage('packages/a', { name: 'a', version: '1.2.3' }, { indent: '\t', trailingNewline: '\n' })
      writePackage('packages/b', { name: 'b', version: '1.2.3' }, { indent: 4, trailingNewline: '\n' })
      const workspaces = resolveWorkspaces(tmp, 'packages/*')
      const rootPkg = { name: 'root', private: true }

      const files = buildBumpFileSet({
        monorepo: true,
        workspaces,
        rootPkg,
        rootPkgSource: sourceOf(rootPkg),
        currentVersion: '1.2.3',
        newVersion: '1.2.4',
      })

      const byPath = Object.fromEntries(files.map(f => [f.path, f.content]))
      expect(byPath['packages/a/package.json']).toBe('{\n\t"name": "a",\n\t"version": "1.2.4"\n}\n')
      expect(byPath['packages/b/package.json']).toBe('{\n    "name": "b",\n    "version": "1.2.4"\n}\n')
    })
  })
})