local config = require('vimpack.config')
local installer = require('vimpack.installer')
local manifest = require('vimpack.manifest')
local plan = require('vimpack.plan')

local reg = { kind = 'template', url_template = 'https://h/${name}-${version}.tar.gz' }

local function cfg_with(plugins)
  return assert(config.normalize({ registry = reg, plugins = plugins }))
end

describe('plan', function()
  it('installs what is not on disk', function()
    local built = plan.build(cfg_with({ { name = 'a', version = '1' } }), manifest.empty(), {})
    assert_eq(1, #built.install)
    assert_eq('not installed', built.install[1].reason)
  end)

  it('skips an install that already matches', function()
    local data = manifest.empty()
    manifest.set(data, 'a', { version = '1', sha256 = 'ff', opt = false })
    local built = plan.build(cfg_with({ { name = 'a', version = '1' } }), data, { a = { opt = false, dir = '/x/a' } })
    assert_eq(0, #built.install)
    assert_eq(0, #built.update)
    assert_eq(1, #built.skip)
  end)

  it('updates on a version bump', function()
    local data = manifest.empty()
    manifest.set(data, 'a', { version = '1', opt = false })
    local built = plan.build(cfg_with({ { name = 'a', version = '2' } }), data, { a = { opt = false, dir = '/x/a' } })
    assert_eq(1, #built.update)
    assert_match('1 -> 2', built.update[1].reason)
  end)

  it('updates when the spec sha256 differs from the installed one', function()
    local data = manifest.empty()
    manifest.set(data, 'a', { version = '1', sha256 = 'aa', opt = false })
    local built = plan.build(
      cfg_with({ { name = 'a', version = '1', sha256 = 'bb' } }),
      data,
      { a = { opt = false, dir = '/x/a' } }
    )
    assert_eq(1, #built.update)
    assert_match('sha256', built.update[1].reason)
  end)

  it('updates when a plugin moves between start and opt', function()
    local data = manifest.empty()
    manifest.set(data, 'a', { version = '1', opt = false })
    local built = plan.build(
      cfg_with({ { name = 'a', version = '1', opt = true } }),
      data,
      { a = { opt = false, dir = '/x/start/a' } }
    )
    assert_eq(1, #built.update)
    assert_match('opt/', built.update[1].reason)
  end)

  it('updates a directory with no manifest entry', function()
    local built =
      plan.build(cfg_with({ { name = 'a', version = '1' } }), manifest.empty(), { a = { opt = false, dir = '/x/a' } })
    assert_eq(1, #built.update)
    assert_match('no manifest entry', built.update[1].reason)
  end)

  it('flags orphans on disk and in the manifest', function()
    local data = manifest.empty()
    manifest.set(data, 'ghost', { version = '9' })
    local built = plan.build(
      cfg_with({ { name = 'a', version = '1' } }),
      data,
      { a = { opt = false, dir = '/x/a' }, old = { opt = true, dir = '/x/opt/old' } }
    )
    assert_eq(2, #built.orphans)
    assert_eq('ghost', built.orphans[1].name)
    assert_eq('old', built.orphans[2].name)
    assert_eq('/x/opt/old', built.orphans[2].dir)
  end)
end)

describe('status_rows', function()
  it('reports one row per plugin plus orphans', function()
    local data = manifest.empty()
    manifest.set(data, 'a', { version = '1', opt = false })
    local rows = plan.status_rows(
      cfg_with({ { name = 'a', version = '2' }, { name = 'b', version = '1' } }),
      data,
      { a = { opt = false, dir = '/x/a' }, gone = { opt = false, dir = '/x/gone' } }
    )
    assert_eq(3, #rows)
    assert_eq({ 'a', 'b', 'gone' }, { rows[1].name, rows[2].name, rows[3].name })
    assert_eq({ 'drift', 'missing', 'orphan' }, { rows[1].state, rows[2].state, rows[3].state })
    assert_eq('1', rows[1].installed)
    assert_eq('2', rows[1].wanted)
  end)
end)

describe('run_tasks', function()
  it('runs every item and respects the concurrency cap', function()
    local items = { 1, 2, 3, 4, 5 }
    local inflight, peak, seen = 0, 0, {}
    local done_results
    installer.run_tasks(items, 2, function(item, cb)
      inflight = inflight + 1
      peak = math.max(peak, inflight)
      vim.schedule(function()
        seen[#seen + 1] = item
        inflight = inflight - 1
        cb(true)
      end)
    end, function(results)
      done_results = results
    end)
    vim.wait(1000, function()
      return done_results ~= nil
    end)
    assert_eq(5, #done_results)
    assert_eq(5, #seen)
    assert_true(peak <= 2, 'peak concurrency was ' .. peak)
  end)

  it('completes immediately on an empty list', function()
    local called = false
    installer.run_tasks({}, 4, function() end, function()
      called = true
    end)
    assert_true(called)
  end)

  it('carries failures through', function()
    local results
    installer.run_tasks({ 'a' }, 1, function(_, cb)
      cb(false, 'boom')
    end, function(r)
      results = r
    end)
    assert_eq('boom', results[1].err)
  end)
end)