local cache = require('canola.cache')
local constants = require('canola.constants')
local mutator = require('canola.mutator')
local test_adapter = require('canola.adapters.test')
local test_util = require('spec.test_util')

local FIELD_ID = constants.FIELD_ID
local FIELD_NAME = constants.FIELD_NAME
local FIELD_TYPE = constants.FIELD_TYPE

describe('mutator', function()
  after_each(function()
    test_util.reset_editor()
  end)

  describe('build actions', function()
    it('empty diffs produce no actions', function()
      vim.cmd.edit({ args = { 'canola-test:///foo/' } })
      local bufnr = vim.api.nvim_get_current_buf()
      local actions = mutator.create_actions_from_diffs({
        [bufnr] = {},
      })
      assert.are.same({}, actions)
    end)

    it('constructs CREATE actions', function()
      vim.cmd.edit({ args = { 'canola-test:///foo/' } })
      local bufnr = vim.api.nvim_get_current_buf()
      local diffs = {
        { type = 'new', name = 'a.txt', entry_type = 'file' },
      }
      local actions = mutator.create_actions_from_diffs({
        [bufnr] = diffs,
      })
      assert.are.same({
        {
          type = 'create',
          entry_type = 'file',
          url = 'canola-test:///foo/a.txt',
        },
      }, actions)
    end)

    it('constructs DELETE actions', function()
      local file = test_adapter.test_set('/foo/a.txt', 'file')
      vim.cmd.edit({ args = { 'canola-test:///foo/' } })
      local bufnr = vim.api.nvim_get_current_buf()
      local diffs = {
        { type = 'delete', name = 'a.txt', id = file[FIELD_ID] },
      }
      local actions = mutator.create_actions_from_diffs({
        [bufnr] = diffs,
      })
      assert.are.same({
        {
          type = 'delete',
          entry_type = 'file',
          url = 'canola-test:///foo/a.txt',
        },
      }, actions)
    end)

    it('constructs COPY actions', function()
      local file = test_adapter.test_set('/foo/a.txt', 'file')
      vim.cmd.edit({ args = { 'canola-test:///foo/' } })
      local bufnr = vim.api.nvim_get_current_buf()
      local diffs = {
        { type = 'new', name = 'b.txt', entry_type = 'file', id = file[FIELD_ID] },
      }
      local actions = mutator.create_actions_from_diffs({
        [bufnr] = diffs,
      })
      assert.are.same({
        {
          type = 'copy',
          entry_type = 'file',
          src_url = 'canola-test:///foo/a.txt',
          dest_url = 'canola-test:///foo/b.txt',
        },
      }, actions)
    end)

    it('constructs MOVE actions', function()
      local file = test_adapter.test_set('/foo/a.txt', 'file')
      vim.cmd.edit({ args = { 'canola-test:///foo/' } })
      local bufnr = vim.api.nvim_get_current_buf()
      local diffs = {
        { type = 'delete', name = 'a.txt', id = file[FIELD_ID] },
        { type = 'new', name = 'b.txt', entry_type = 'file', id = file[FIELD_ID] },
      }
      local actions = mutator.create_actions_from_diffs({
        [bufnr] = diffs,
      })
      assert.are.same({
        {
          type = 'move',
          entry_type = 'file',
          src_url = 'canola-test:///foo/a.txt',
          dest_url = 'canola-test:///foo/b.txt',
        },
      }, actions)
    end)

    it('correctly orders MOVE + CREATE', function()
      local file = test_adapter.test_set('/a.txt', 'file')
      vim.cmd.edit({ args = { 'canola-test:///' } })
      local bufnr = vim.api.nvim_get_current_buf()
      local diffs = {
        { type = 'delete', name = 'a.txt', id = file[FIELD_ID] },
        { type = 'new', name = 'b.txt', entry_type = 'file', id = file[FIELD_ID] },
        { type = 'new', name = 'a.txt', entry_type = 'file' },
      }
      local actions = mutator.create_actions_from_diffs({
        [bufnr] = diffs,
      })
      assert.are.same({
        {
          type = 'move',
          entry_type = 'file',
          src_url = 'canola-test:///a.txt',
          dest_url = 'canola-test:///b.txt',
        },
        {
          type = 'create',
          entry_type = 'file',
          url = 'canola-test:///a.txt',
        },
      }, actions)
    end)

    it('resolves MOVE loops', function()
      local afile = test_adapter.test_set('/a.txt', 'file')
      local bfile = test_adapter.test_set('/b.txt', 'file')
      vim.cmd.edit({ args = { 'canola-test:///' } })
      local bufnr = vim.api.nvim_get_current_buf()
      local diffs = {
        { type = 'delete', name = 'a.txt', id = afile[FIELD_ID] },
        { type = 'new', name = 'b.txt', entry_type = 'file', id = afile[FIELD_ID] },
        { type = 'delete', name = 'b.txt', id = bfile[FIELD_ID] },
        { type = 'new', name = 'a.txt', entry_type = 'file', id = bfile[FIELD_ID] },
      }
      math.randomseed(2983982)
      local actions = mutator.create_actions_from_diffs({
        [bufnr] = diffs,
      })
      local tmp_url = 'canola-test:///a.txt__canola_tmp_510852'
      assert.are.same({
        {
          type = 'move',
          entry_type = 'file',
          src_url = 'canola-test:///a.txt',
          dest_url = tmp_url,
        },
        {
          type = 'move',
          entry_type = 'file',
          src_url = 'canola-test:///b.txt',
          dest_url = 'canola-test:///a.txt',
        },
        {
          type = 'move',
          entry_type = 'file',
          src_url = tmp_url,
          dest_url = 'canola-test:///b.txt',
        },
      }, actions)
    end)
  end)

  describe('order actions', function()
    it('Creates files inside dir before move', function()
      local move = {
        type = 'move',
        src_url = 'canola-test:///a',
        dest_url = 'canola-test:///b',
        entry_type = 'directory',
      }
      local create = { type = 'create', url = 'canola-test:///a/hi.txt', entry_type = 'file' }
      local actions = { move, create }
      local ordered_actions = mutator.enforce_action_order(actions)
      assert.are.same({ create, move }, ordered_actions)
    end)

    it('Moves file out of parent before deleting parent', function()
      local move = {
        type = 'move',
        src_url = 'canola-test:///a/b.txt',
        dest_url = 'canola-test:///b.txt',
        entry_type = 'file',
      }
      local delete = { type = 'delete', url = 'canola-test:///a', entry_type = 'directory' }
      local actions = { delete, move }
      local ordered_actions = mutator.enforce_action_order(actions)
      assert.are.same({ move, delete }, ordered_actions)
    end)

    it('Handles parent child move ordering', function()
      local move1 = {
        type = 'move',
        src_url = 'canola-test:///a/b',
        dest_url = 'canola-test:///b',
        entry_type = 'directory',
      }
      local move2 = {
        type = 'move',
        src_url = 'canola-test:///a',
        dest_url = 'canola-test:///b/a',
        entry_type = 'directory',
      }
      local actions = { move2, move1 }
      local ordered_actions = mutator.enforce_action_order(actions)
      assert.are.same({ move1, move2 }, ordered_actions)
    end)

    it('Handles a delete inside a moved folder', function()
      local del = {
        type = 'delete',
        url = 'canola-test:///a/b.txt',
        entry_type = 'file',
      }
      local move = {
        type = 'move',
        src_url = 'canola-test:///a',
        dest_url = 'canola-test:///b',
        entry_type = 'directory',
      }
      local actions = { move, del }
      local ordered_actions = mutator.enforce_action_order(actions)
      assert.are.same({ del, move }, ordered_actions)
    end)

    it('Detects move directory loops', function()
      local move = {
        type = 'move',
        src_url = 'canola-test:///a',
        dest_url = 'canola-test:///a/b',
        entry_type = 'directory',
      }
      assert.has_error(function()
        mutator.enforce_action_order({ move })
      end)
    end)

    it('Detects copy directory loops', function()
      local move = {
        type = 'copy',
        src_url = 'canola-test:///a',
        dest_url = 'canola-test:///a/b',
        entry_type = 'directory',
      }
      assert.has_error(function()
        mutator.enforce_action_order({ move })
      end)
    end)

    it('Detects nested copy directory loops', function()
      local move = {
        type = 'copy',
        src_url = 'canola-test:///a',
        dest_url = 'canola-test:///a/b/a',
        entry_type = 'directory',
      }
      assert.has_error(function()
        mutator.enforce_action_order({ move })
      end)
    end)

    describe('change', function()
      it('applies CHANGE after CREATE', function()
        local create = { type = 'create', url = 'canola-test:///a/hi.txt', entry_type = 'file' }
        local change = {
          type = 'change',
          url = 'canola-test:///a/hi.txt',
          entry_type = 'file',
          column = 'TEST',
          value = 'TEST',
        }
        local actions = { change, create }
        local ordered_actions = mutator.enforce_action_order(actions)
        assert.are.same({ create, change }, ordered_actions)
      end)

      it('applies CHANGE after COPY src', function()
        local copy = {
          type = 'copy',
          src_url = 'canola-test:///a/hi.txt',
          dest_url = 'canola-test:///b.txt',
          entry_type = 'file',
        }
        local change = {
          type = 'change',
          url = 'canola-test:///a/hi.txt',
          entry_type = 'file',
          column = 'TEST',
          value = 'TEST',
        }
        local actions = { change, copy }
        local ordered_actions = mutator.enforce_action_order(actions)
        assert.are.same({ copy, change }, ordered_actions)
      end)

      it('applies CHANGE after COPY dest', function()
        local copy = {
          type = 'copy',
          src_url = 'canola-test:///b.txt',
          dest_url = 'canola-test:///a/hi.txt',
          entry_type = 'file',
        }
        local change = {
          type = 'change',
          url = 'canola-test:///a/hi.txt',
          entry_type = 'file',
          column = 'TEST',
          value = 'TEST',
        }
        local actions = { change, copy }
        local ordered_actions = mutator.enforce_action_order(actions)
        assert.are.same({ copy, change }, ordered_actions)
      end)

      it('applies CHANGE after MOVE dest', function()
        local move = {
          type = 'move',
          src_url = 'canola-test:///b.txt',
          dest_url = 'canola-test:///a/hi.txt',
          entry_type = 'file',
        }
        local change = {
          type = 'change',
          url = 'canola-test:///a/hi.txt',
          entry_type = 'file',
          column = 'TEST',
          value = 'TEST',
        }
        local actions = { change, move }
        local ordered_actions = mutator.enforce_action_order(actions)
        assert.are.same({ move, change }, ordered_actions)
      end)
    end)
  end)

  describe('perform actions', function()
    it('creates new entries', function()
      local actions = {
        { type = 'create', url = 'canola-test:///a.txt', entry_type = 'file' },
      }
      test_util.await(mutator.process_actions, 2, actions)
      local files = cache.list_url('canola-test:///')
      assert.are.same({
        ['a.txt'] = {
          [FIELD_ID] = 1,
          [FIELD_TYPE] = 'file',
          [FIELD_NAME] = 'a.txt',
        },
      }, files)
    end)

    it('deletes entries', function()
      local file = test_adapter.test_set('/a.txt', 'file')
      local actions = {
        { type = 'delete', url = 'canola-test:///a.txt', entry_type = 'file' },
      }
      test_util.await(mutator.process_actions, 2, actions)
      local files = cache.list_url('canola-test:///')
      assert.are.same({}, files)
      assert.is_nil(cache.get_entry_by_id(file[FIELD_ID]))
      assert.has_error(function()
        cache.get_parent_url(file[FIELD_ID])
      end)
    end)

    it('moves entries', function()
      local file = test_adapter.test_set('/a.txt', 'file')
      local actions = {
        {
          type = 'move',
          src_url = 'canola-test:///a.txt',
          dest_url = 'canola-test:///b.txt',
          entry_type = 'file',
        },
      }
      test_util.await(mutator.process_actions, 2, actions)
      local files = cache.list_url('canola-test:///')
      local new_entry = {
        [FIELD_ID] = file[FIELD_ID],
        [FIELD_TYPE] = 'file',
        [FIELD_NAME] = 'b.txt',
      }
      assert.are.same({
        ['b.txt'] = new_entry,
      }, files)
      assert.are.same(new_entry, cache.get_entry_by_id(file[FIELD_ID]))
      assert.equals('canola-test:///', cache.get_parent_url(file[FIELD_ID]))
    end)

    it('copies entries', function()
      local file = test_adapter.test_set('/a.txt', 'file')
      local actions = {
        {
          type = 'copy',
          src_url = 'canola-test:///a.txt',
          dest_url = 'canola-test:///b.txt',
          entry_type = 'file',
        },
      }
      test_util.await(mutator.process_actions, 2, actions)
      local files = cache.list_url('canola-test:///')
      local new_entry = {
        [FIELD_ID] = file[FIELD_ID] + 1,
        [FIELD_TYPE] = 'file',
        [FIELD_NAME] = 'b.txt',
      }
      assert.are.same({
        ['a.txt'] = file,
        ['b.txt'] = new_entry,
      }, files)
    end)
  end)
end)