import { describe, expect, it, vi } from 'vitest'
import { join } from 'node:path'
import { parseSshConfig, sshConfigHostsToTargets, parseSshGOutput } from './ssh-config-parser'

vi.mock('os', () => ({
  homedir: () => '/home/testuser'
}))

const LARGE_HOST_ALIAS_COUNT = 150_000
const TEST_HOME = '/home/testuser'

function testHomePath(...parts: string[]): string {
  return join(TEST_HOME, ...parts)
}

function buildHostAliases(count: number): string {
  const aliases: string[] = []
  for (let index = 0; index < count; index += 1) {
    aliases.push(`generated-${index}`)
  }
  return aliases.join(' ')
}

describe('parseSshConfig', () => {
  it('parses a basic host block', () => {
    const config = `
Host myserver
  HostName 192.168.1.100
  User deploy
  Port 2222
`
    const hosts = parseSshConfig(config)
    expect(hosts).toHaveLength(1)
    expect(hosts[0]).toEqual({
      host: 'myserver',
      hostname: '192.168.1.100',
      user: 'deploy',
      port: 2222
    })
  })

  it('parses multiple host blocks', () => {
    const config = `
Host staging
  HostName staging.example.com
  User admin

Host production
  HostName prod.example.com
  User deploy
  Port 2222
`
    const hosts = parseSshConfig(config)
    expect(hosts).toHaveLength(2)
    expect(hosts[0].host).toBe('staging')
    expect(hosts[1].host).toBe('production')
    expect(hosts[1].port).toBe(2222)
  })

  it('skips wildcard-only Host entries', () => {
    const config = `
Host *
  ServerAliveInterval 60

Host myserver
  HostName 10.0.0.1
`
    const hosts = parseSshConfig(config)
    expect(hosts).toHaveLength(1)
    expect(hosts[0].host).toBe('myserver')
  })

  it('skips Host entries with only pattern characters', () => {
    const config = `
Host *.example.com
  User admin

Host dev
  HostName dev.example.com
`
    const hosts = parseSshConfig(config)
    expect(hosts).toHaveLength(1)
    expect(hosts[0].host).toBe('dev')
  })

  it('parses IdentityFile with ~ expansion', () => {
    const config = `
Host myserver
  HostName example.com
  IdentityFile ~/.ssh/id_ed25519
`
    const hosts = parseSshConfig(config)
    expect(hosts[0].identityFile).toBe(testHomePath('.ssh', 'id_ed25519'))
  })

  it('parses Windows-style IdentityFile with ~ expansion', () => {
    const config = `
Host myserver
  HostName example.com
  IdentityFile ~\\.ssh\\id_ed25519
`
    const hosts = parseSshConfig(config)
    expect(hosts[0].identityFile).toBe(testHomePath('.ssh', 'id_ed25519'))
  })

  it('parses quoted scalar values like OpenSSH', () => {
    const config = `
Host quoted
  HostName "localhost" # local test
  User "deploy" # deploy user
  Port "2202" # ssh port
  IdentityFile "~/.ssh/id with space" # private key
  IdentityAgent "~/.1password/agent sock" # agent socket
  IdentitiesOnly "yes" # limit keys
  ProxyJump "bastion" # jump host
`
    const hosts = parseSshConfig(config)
    expect(hosts[0]).toEqual({
      host: 'quoted',
      hostname: 'localhost',
      user: 'deploy',
      port: 2202,
      identityFile: testHomePath('.ssh', 'id with space'),
      identityAgent: testHomePath('.1password', 'agent sock'),
      identitiesOnly: true,
      proxyJump: 'bastion'
    })
  })

  it('parses equals-form scalar directives', () => {
    const config = `
Host eq
  HostName=eq.example.com
  User=deploy
  Port=2202
`
    const hosts = parseSshConfig(config)
    expect(hosts[0]).toEqual({
      host: 'eq',
      hostname: 'eq.example.com',
      user: 'deploy',
      port: 2202
    })
  })

  it('parses IdentityAgent with ~ expansion', () => {
    const config = `
Host myserver
  HostName example.com
  IdentityAgent ~/.1password/agent.sock
`
    const hosts = parseSshConfig(config)
    expect(hosts[0].identityAgent).toBe(testHomePath('.1password', 'agent.sock'))
  })

  it('parses IdentitiesOnly', () => {
    const config = `
Host myserver
  HostName example.com
  IdentitiesOnly yes
`
    const hosts = parseSshConfig(config)
    expect(hosts[0].identitiesOnly).toBe(true)
  })

  it('parses ProxyCommand, ProxyUseFdpass, and ProxyJump', () => {
    const config = `
Host internal
  HostName 10.0.0.5
  ProxyCommand ssh -W %h:%p bastion
  ProxyUseFdpass yes
  ProxyJump bastion.example.com
`
    const hosts = parseSshConfig(config)
    expect(hosts[0].proxyCommand).toBe('ssh -W %h:%p bastion')
    expect(hosts[0].proxyUseFdpass).toBe(true)
    expect(hosts[0].proxyJump).toBe('bastion.example.com')
  })

  it('preserves ProxyCommand as the rest of the line', () => {
    const config = `
Host internal
  ProxyCommand sh -c "nc %h %p" # shell comment
`
    const hosts = parseSshConfig(config)
    expect(hosts[0].proxyCommand).toBe('sh -c "nc %h %p" # shell comment')
  })

  it('ignores comments and blank lines', () => {
    const config = `
# This is a comment
Host myserver
  # Another comment
  HostName example.com

  User admin
`
    const hosts = parseSshConfig(config)
    expect(hosts).toHaveLength(1)
    expect(hosts[0].user).toBe('admin')
  })

  it('handles case-insensitive keywords', () => {
    const config = `
Host myserver
  hostname EXAMPLE.COM
  user Admin
  port 3022
`
    const hosts = parseSshConfig(config)
    expect(hosts[0].hostname).toBe('EXAMPLE.COM')
    expect(hosts[0].user).toBe('Admin')
    expect(hosts[0].port).toBe(3022)
  })

  it('stops current block on Match directive', () => {
    const config = `
Host myserver
  HostName example.com

Match host *.internal
  User internal-admin

Host other
  HostName other.com
`
    const hosts = parseSshConfig(config)
    expect(hosts).toHaveLength(2)
    expect(hosts[0].host).toBe('myserver')
    expect(hosts[1].host).toBe('other')
  })

  it('returns empty array for empty input', () => {
    expect(parseSshConfig('')).toEqual([])
  })

  it('creates one parsed host per concrete alias on a multi-pattern Host line', () => {
    const config = `
Host staging stage *.example.com
  HostName staging.example.com
`
    const hosts = parseSshConfig(config)
    expect(hosts).toEqual([
      { host: 'staging', hostname: 'staging.example.com' },
      { host: 'stage', hostname: 'staging.example.com' }
    ])
  })

  it('parses large concrete alias lists on one Host line', () => {
    const config = [
      `Host ${buildHostAliases(LARGE_HOST_ALIAS_COUNT)}`,
      '  HostName generated.example.com',
      'Host after',
      '  HostName after.example.com'
    ].join('\n')

    const hosts = parseSshConfig(config)

    expect(hosts).toHaveLength(LARGE_HOST_ALIAS_COUNT + 1)
    expect(hosts[0]).toEqual({
      host: 'generated-0',
      hostname: 'generated.example.com'
    })
    expect(hosts[LARGE_HOST_ALIAS_COUNT - 1]).toEqual({
      host: `generated-${LARGE_HOST_ALIAS_COUNT - 1}`,
      hostname: 'generated.example.com'
    })
    expect(hosts.at(-1)).toEqual({
      host: 'after',
      hostname: 'after.example.com'
    })
  })

  it('applies identity agent settings to every concrete alias on a multi-pattern Host line', () => {
    const config = `
Host staging stage
  IdentityAgent ~/.1password/agent.sock
  IdentitiesOnly yes
`
    const hosts = parseSshConfig(config)
    expect(hosts).toEqual([
      {
        host: 'staging',
        identityAgent: testHomePath('.1password', 'agent.sock'),
        identitiesOnly: true
      },
      {
        host: 'stage',
        identityAgent: testHomePath('.1password', 'agent.sock'),
        identitiesOnly: true
      }
    ])
  })

  it('defaults port to 22 for invalid port values', () => {
    const config = `
Host myserver
  Port notanumber
`
    const hosts = parseSshConfig(config)
    expect(hosts[0].port).toBe(22)
  })
})

describe('sshConfigHostsToTargets', () => {
  it('converts hosts to SshTarget objects', () => {
    const hosts = [{ host: 'myserver', hostname: '10.0.0.1', port: 22, user: 'deploy' }]
    const targets = sshConfigHostsToTargets(hosts, new Set())
    expect(targets).toHaveLength(1)
    expect(targets[0]).toMatchObject({
      label: 'myserver',
      host: '10.0.0.1',
      port: 22,
      username: 'deploy'
    })
    expect(targets[0].id).toMatch(/^ssh-/)
  })

  it('uses host alias as hostname when HostName is missing', () => {
    const hosts = [{ host: 'myserver' }]
    const targets = sshConfigHostsToTargets(hosts, new Set())
    expect(targets[0].host).toBe('myserver')
  })

  it('skips hosts that are already imported', () => {
    const hosts = [
      { host: 'existing', hostname: '10.0.0.1' },
      { host: 'new-host', hostname: '10.0.0.2' }
    ]
    const targets = sshConfigHostsToTargets(hosts, new Set(['existing']))
    expect(targets).toHaveLength(1)
    expect(targets[0].label).toBe('new-host')
  })

  it('defaults username to empty string when not specified', () => {
    const hosts = [{ host: 'nouser', hostname: '10.0.0.1' }]
    const targets = sshConfigHostsToTargets(hosts, new Set())
    expect(targets[0].username).toBe('')
  })

  it('carries through identityFile, identityAgent, identitiesOnly, proxyCommand, and jumpHost', () => {
    const hosts = [
      {
        host: 'internal',
        hostname: '10.0.0.5',
        identityFile: '/home/user/.ssh/id_rsa',
        identityAgent: '/home/user/.1password/agent.sock',
        identitiesOnly: true,
        proxyCommand: 'ssh -W %h:%p bastion',
        proxyUseFdpass: true,
        proxyJump: 'bastion.example.com'
      }
    ]
    const targets = sshConfigHostsToTargets(hosts, new Set())
    expect(targets[0].identityFile).toBe('/home/user/.ssh/id_rsa')
    expect(targets[0].identityAgent).toBe('/home/user/.1password/agent.sock')
    expect(targets[0].identitiesOnly).toBe(true)
    expect(targets[0].proxyCommand).toBe('ssh -W %h:%p bastion')
    expect(targets[0].jumpHost).toBe('bastion.example.com')
  })

  it('imports duplicate aliases only once and keeps the first concrete host', () => {
    const hosts = [
      { host: 'dup', hostname: 'first.example.com', user: 'first' },
      { host: 'dup', hostname: 'second.example.com', user: 'second' }
    ]
    const targets = sshConfigHostsToTargets(hosts, new Set())

    expect(targets).toHaveLength(1)
    expect(targets[0]).toMatchObject({
      label: 'dup',
      host: 'first.example.com',
      username: 'first'
    })
  })
})

// ── parseSshGOutput ──────────────────────────────────────────────────

describe('parseSshGOutput', () => {
  it('parses hostname, user, port from ssh -G output', () => {
    const output = [
      'hostname 192.168.1.100',
      'user deploy',
      'port 2222',
      'identityfile /home/testuser/.ssh/id_ed25519',
      'forwardagent no'
    ].join('\n')

    const result = parseSshGOutput(output)
    expect(result.hostname).toBe('192.168.1.100')
    expect(result.user).toBe('deploy')
    expect(result.port).toBe(2222)
    expect(result.identityFile).toEqual(['/home/testuser/.ssh/id_ed25519'])
    expect(result.forwardAgent).toBe(false)
  })

  it('collects multiple identity files', () => {
    const output = [
      'hostname example.com',
      'identityfile ~/.ssh/id_ed25519',
      'identityfile ~/.ssh/id_rsa',
      'port 22'
    ].join('\n')

    const result = parseSshGOutput(output)
    expect(result.identityFile).toEqual([
      testHomePath('.ssh', 'id_ed25519'),
      testHomePath('.ssh', 'id_rsa')
    ])
  })

  it('parses forwardagent yes', () => {
    const output = 'hostname example.com\nforwardagent yes\nport 22'
    const result = parseSshGOutput(output)
    expect(result.forwardAgent).toBe(true)
  })

  it('defaults port to 22 when missing', () => {
    const output = 'hostname example.com'
    const result = parseSshGOutput(output)
    expect(result.port).toBe(22)
  })

  it('returns empty hostname when missing', () => {
    const output = 'user admin\nport 22'
    const result = parseSshGOutput(output)
    expect(result.hostname).toBe('')
  })

  it('returns undefined user when missing', () => {
    const output = 'hostname example.com\nport 22'
    const result = parseSshGOutput(output)
    expect(result.user).toBeUndefined()
  })

  it('handles empty output', () => {
    const result = parseSshGOutput('')
    expect(result.hostname).toBe('')
    expect(result.port).toBe(22)
    expect(result.identityFile).toEqual([])
  })

  it('skips lines without spaces', () => {
    const output = 'hostname example.com\nbadline\nport 22'
    const result = parseSshGOutput(output)
    expect(result.hostname).toBe('example.com')
    expect(result.port).toBe(22)
  })

  it('parses proxycommand and filters "none"', () => {
    const output = 'hostname example.com\nproxycommand ssh -W %h:%p bastion\nport 22'
    const result = parseSshGOutput(output)
    expect(result.proxyCommand).toBe('ssh -W %h:%p bastion')

    const noneOutput = 'hostname example.com\nproxycommand none\nport 22'
    const noneResult = parseSshGOutput(noneOutput)
    expect(noneResult.proxyCommand).toBeUndefined()
  })

  it('parses proxyusefdpass yes', () => {
    const output = 'hostname example.com\nproxyusefdpass yes\nport 22'
    const result = parseSshGOutput(output)
    expect(result.proxyUseFdpass).toBe(true)

    const noneOutput = 'hostname example.com\nproxyusefdpass no\nport 22'
    const noneResult = parseSshGOutput(noneOutput)
    expect(noneResult.proxyUseFdpass).toBe(false)
  })

  it('parses proxyjump and filters "none"', () => {
    const output = 'hostname example.com\nproxyjump bastion.example.com\nport 22'
    const result = parseSshGOutput(output)
    expect(result.proxyJump).toBe('bastion.example.com')

    const noneOutput = 'hostname example.com\nproxyjump none\nport 22'
    const noneResult = parseSshGOutput(noneOutput)
    expect(noneResult.proxyJump).toBeUndefined()
  })

  it('handles ~ expansion in identity file paths', () => {
    const output = 'hostname example.com\nidentityfile ~/custom_key\nport 22'
    const result = parseSshGOutput(output)
    expect(result.identityFile).toEqual([testHomePath('custom_key')])
  })

  it('handles Windows-style ~ expansion in identity file paths', () => {
    const output = 'hostname example.com\nidentityfile ~\\.ssh\\custom_key\nport 22'
    const result = parseSshGOutput(output)
    expect(result.identityFile).toEqual([testHomePath('.ssh', 'custom_key')])
  })

  it('parses identityagent with ~ expansion', () => {
    const output = 'hostname example.com\nidentityagent ~/.1password/agent.sock\nport 22'
    const result = parseSshGOutput(output)
    expect(result.identityAgent).toBe(testHomePath('.1password', 'agent.sock'))
  })

  it('preserves identityagent none so auth can disable agent fallback', () => {
    const output = 'hostname example.com\nidentityagent none\nport 22'
    const result = parseSshGOutput(output)
    expect(result.identityAgent).toBe('none')
  })

  it('parses identitiesonly yes', () => {
    const output = 'hostname example.com\nidentitiesonly yes\nport 22'
    const result = parseSshGOutput(output)
    expect(result.identitiesOnly).toBe(true)
  })

  it('parses controlmaster options and filters controlpath none', () => {
    const output = [
      'hostname example.com',
      'controlmaster auto',
      'controlpath ~/.ssh/cm/%r@%h:%p',
      'controlpersist 10m',
      'port 22'
    ].join('\n')
    const result = parseSshGOutput(output)
    expect(result.controlMaster).toBe('auto')
    expect(result.controlPath).toBe(testHomePath('.ssh', 'cm', '%r@%h:%p'))
    expect(result.controlPersist).toBe('10m')

    const noneResult = parseSshGOutput(
      'hostname example.com\ncontrolmaster no\ncontrolpath none\ncontrolpersist no\nport 22'
    )
    expect(noneResult.controlMaster).toBe('no')
    expect(noneResult.controlPath).toBeUndefined()
    expect(noneResult.controlPersist).toBe('no')
  })
})