From 819a4620de30d576ce2925c9176d9be18b505d12 Mon Sep 17 00:00:00 2001
From: "Scott E. Graves" <scott.e.graves@protonmail.com>
Date: Fri, 29 Jul 2022 09:46:02 -0500
Subject: [PATCH] initial commit

---
 doc/.keep                     |   0
 lua/nvim-haven/init.lua       | 582 ++++++++++++++++++++++++++++++++++
 lua/nvim-haven/utils/init.lua |  58 ++++
 plugin/nvim-haven.lua         |   4 +
 4 files changed, 644 insertions(+)
 create mode 100644 doc/.keep
 create mode 100644 lua/nvim-haven/init.lua
 create mode 100644 lua/nvim-haven/utils/init.lua
 create mode 100644 plugin/nvim-haven.lua

diff --git a/doc/.keep b/doc/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/lua/nvim-haven/init.lua b/lua/nvim-haven/init.lua
new file mode 100644
index 0000000..193fc0a
--- /dev/null
+++ b/lua/nvim-haven/init.lua
@@ -0,0 +1,582 @@
+local action_state = require("telescope.actions.state")
+local actions = require("telescope.actions")
+local conf = require("telescope.config").values
+local finders = require("telescope.finders")
+local global_state = require("telescope.state")
+local pfiletype = require("plenary.filetype")
+local pickers = require("telescope.pickers")
+local previewers = require("telescope.previewers")
+local putils = require("telescope.previewers.utils")
+local utils = require("nvim-haven.utils")
+
+local ns_previewer = vim.api.nvim_create_namespace("telescope.previewers")
+
+local M = {}
+
+local active_saves = {}
+local changed_lookup = {}
+local directory_sep = utils.iff(utils.is_windows, "\\", "/")
+local haven_config = {
+  enabled = true,
+  exclusions = {
+    function(path, _)
+      if utils.is_windows then
+        return path:lower():starts_with((vim.fn.eval("$VIMRUNTIME") .. directory_sep):lower())
+      end
+      return path:starts_with(vim.fn.eval("$VIMRUNTIME") .. directory_sep)
+    end,
+    function(path, _)
+      if utils.is_windows then
+        return path:lower():starts_with((vim.fn.stdpath("data") .. directory_sep):lower())
+      end
+      return path:starts_with(vim.fn.stdpath("data") .. directory_sep)
+    end,
+    function(path, _)
+      if utils.is_windows then
+        return path:lower():starts_with(
+          (utils.create_path(vim.fn.eval("$XDG_CONFIG_HOME"), "coc") .. directory_sep):lower()
+        )
+      end
+      return path:starts_with(
+        utils.create_path(vim.fn.eval("$XDG_CONFIG_HOME"), "coc") .. directory_sep
+      )
+    end,
+    function(path, _)
+      if utils.is_windows then
+        return path:lower():ends_with(
+          (directory_sep .. ".git" .. directory_sep .. "COMMIT_EDITMSG"):lower()
+        )
+      end
+      return path:ends_with(directory_sep .. ".git" .. directory_sep .. "COMMIT_EDITMSG")
+    end,
+    function(path, config)
+      if utils.is_windows then
+        return path:lower():starts_with((config.haven_path .. directory_sep):lower())
+      end
+      return path:starts_with(config.haven_path .. directory_sep)
+    end
+  },
+  haven_path = utils.create_path(vim.fn.stdpath("data"), "nvim-haven"),
+  inclusions = {},
+  max_history_count = 200,
+  save_timeout = 10000
+}
+local line_ending = utils.iff(utils.is_windows, "\r\n", "\n")
+
+local print_message = function(...)
+  print("nvim-haven", ...)
+end
+
+local diff_strings = function(a, b)
+  return vim.diff(a, b, {algorithm = "minimal"})
+end
+
+local encode = function(str)
+  return str:gsub("\r?\n", "\r\n"):gsub(
+    "([^%w%-%.%_%~ ])",
+    function(c)
+      return string.format("%%%02X", string.byte(c))
+    end
+  ):gsub(" ", "+")
+end
+
+local create_save_file = function(buf_info)
+  return utils.create_path(haven_config.haven_path, encode(buf_info.name) .. ".save")
+end
+
+local save_change_file = function(buf_info, lines, save_file)
+  print_message("save_changed_file", buf_info.name)
+  active_saves[save_file] = nil
+
+  local file, err = io.open(save_file, "a")
+  if file == nil then
+    print_message(err)
+    return
+  end
+
+  local file_entry =
+    vim.json.encode(
+    {
+      date = os.time(),
+      ft = pfiletype.detect(buf_info.name, {}),
+      lines = lines
+    }
+  )
+  _, err = file:write(file_entry .. line_ending)
+  if err ~= nil then
+    print_message(err)
+  end
+  file:close()
+end
+
+local save_change_file_entries = function(buf_info, entries, save_file)
+  print_message("save_changed_file", buf_info.name)
+  active_saves[save_file] = nil
+
+  local file, err = io.open(save_file, "w+")
+  if file == nil then
+    print_message(err)
+    return
+  end
+
+  for _, entry in pairs(entries) do
+    _, err = file:write(vim.json.encode(entry) .. line_ending)
+    if err ~= nil then
+      print_message(err)
+    end
+  end
+  file:close()
+end
+
+local read_change_file = function(buf_info, save_file)
+  local file, err = io.open(save_file, "r")
+  if file == nil then
+    return nil, err
+  end
+
+  local save_data
+  save_data, err = file:read("a")
+  if err ~= nil then
+    return nil, err
+  end
+  file:close()
+
+  local entries = vim.json.decode("[" .. table.concat(save_data:split(line_ending), ",") .. "]")
+  if #entries > haven_config.max_history_count then
+    while #entries > haven_config.max_history_count do
+      table.remove(entries, 1)
+    end
+    save_change_file_entries(buf_info, entries, save_file)
+  end
+
+  return entries
+end
+
+local process_file_changed = function(buf_info)
+  local save_file = create_save_file(buf_info)
+  local changed_data = changed_lookup[save_file]
+  local immediate = vim.fn.filereadable(save_file) == 0
+  if
+    not immediate and
+      (changed_data == nil or (buf_info.changed == 0 and changed_data.changed == 0) or
+        buf_info.changedtick == changed_data.changedtick)
+   then
+    changed_lookup[save_file] = {changed = buf_info.changed, changedtick = buf_info.changedtick}
+    return
+  end
+
+  if active_saves[save_file] ~= nil then
+    active_saves[save_file].timer:stop()
+    active_saves[save_file] = nil
+  end
+
+  changed_lookup[save_file] = {changed = buf_info.changed, changedtick = buf_info.changedtick}
+
+  local lines = vim.api.nvim_buf_get_lines(buf_info.bufnr, 0, -1, true)
+
+  local entries, _ = read_change_file(buf_info, save_file)
+  if entries ~= nil then
+    if
+      diff_strings(
+        table.concat(entries[#entries].lines, line_ending),
+        table.concat(lines, line_ending)
+      ):len() == 0
+     then
+      return
+    end
+    entries = nil
+  end
+
+  local saved = false
+  local do_save = function()
+    if not saved then
+      saved = true
+      save_change_file(buf_info, lines, save_file)
+    end
+  end
+
+  if immediate then
+    do_save()
+  else
+    active_saves[save_file] = {
+      timer = vim.defer_fn(do_save, haven_config.save_timeout),
+      do_save = do_save
+    }
+  end
+end
+
+local check_requirements = function()
+  if vim.o.modifiable ~= 0 and vim.o.buftype ~= "nofile" then
+    local buf_info = vim.fn.getbufinfo(vim.fn.bufname())
+    if buf_info ~= nil and #buf_info > 0 then
+      buf_info = buf_info[1]
+      if buf_info.name:len() ~= 0 and vim.fn.filereadable(buf_info.name) ~= 0 then
+        if changed_lookup[create_save_file(buf_info)] == nil then
+          for _, is_included in pairs(haven_config.inclusions) do
+            if is_included(buf_info.name, haven_config) then
+              return true, buf_info
+            end
+          end
+
+          for _, is_excluded in pairs(haven_config.exclusions) do
+            if is_excluded(buf_info.name, haven_config) then
+              return false
+            end
+          end
+        end
+        return true, buf_info
+      end
+    end
+  end
+  return false
+end
+
+local handle_buffer_changed = function()
+  local ok, buf_info = check_requirements()
+  if ok and buf_info ~= nil then
+    process_file_changed(buf_info)
+  end
+end
+
+local handle_vim_leave = function()
+  for _, active in pairs(active_saves) do
+    active.timer:stop()
+    active.do_save()
+  end
+  active_saves = {}
+  changed_lookup = {}
+end
+
+local setup_autocmds = function()
+  local group_id = vim.api.nvim_create_augroup("nvim-haven-internal", {clear = true})
+  if haven_config.enabled then
+    vim.api.nvim_create_autocmd(
+      "BufEnter",
+      {
+        group = group_id,
+        pattern = "*",
+        callback = handle_buffer_changed
+      }
+    )
+    vim.api.nvim_create_autocmd(
+      "InsertLeave",
+      {
+        group = group_id,
+        pattern = "*",
+        callback = handle_buffer_changed
+      }
+    )
+    vim.api.nvim_create_autocmd(
+      "TextChanged",
+      {
+        group = group_id,
+        pattern = "*",
+        callback = handle_buffer_changed
+      }
+    )
+    vim.api.nvim_create_autocmd(
+      "VimLeave",
+      {
+        group = group_id,
+        pattern = "*",
+        callback = handle_vim_leave
+      }
+    )
+  else
+    vim.api.nvim_del_augroup_by_id(group_id)
+  end
+end
+
+local apply_diff_to_lines = function(diff, source_lines)
+  local diff_lines = diff:split(line_ending)
+  local changes = {}
+  local current_diff
+
+  for _, line in pairs(diff_lines) do
+    if line:len() > 0 then
+      if line:starts_with("@@") and line:ends_with("@@") then
+        local diff_range = line:sub(3, -1):sub(1, -3):split(" ")[1]:split(",")
+        if #diff_range == 1 then
+          table.insert(diff_range, "1")
+        end
+
+        local diff_start = math.abs(tonumber(diff_range[1], 10))
+        local diff_count = tonumber(diff_range[2], 10)
+        if diff_count == 0 then
+          diff_start = diff_start + 1
+        end
+
+        current_diff = {
+          diff = {line},
+          next = diff_start + diff_count,
+          start = diff_start
+        }
+        table.insert(changes, current_diff)
+      elseif current_diff ~= nil then
+        table.insert(current_diff.diff, line)
+      end
+    else
+      current_diff = nil
+    end
+  end
+
+  local actual_line = 1
+  local buffer_lines = {}
+  local diff_rows = {}
+  local source_line = 1
+  for _, change in pairs(changes) do
+    while source_line < change.start do
+      table.insert(buffer_lines, source_lines[source_line])
+      actual_line = actual_line + 1
+      source_line = source_line + 1
+    end
+
+    table.insert(diff_rows, actual_line)
+    for _, change_diff_lines in pairs(change.diff) do
+      table.insert(buffer_lines, change_diff_lines)
+      actual_line = actual_line + 1
+    end
+
+    source_line = change.next
+  end
+
+  while source_line <= #source_lines do
+    table.insert(buffer_lines, source_lines[source_line])
+    actual_line = actual_line + 1
+    source_line = source_line + 1
+  end
+
+  return buffer_lines, diff_rows
+end
+
+local show_picker = function(entries)
+  global_state.set_global_key("selected_entry", nil)
+
+  local jump_state
+
+  local jump_to_line = function(self, bufnr, lnum)
+    pcall(vim.api.nvim_buf_clear_namespace, bufnr, ns_previewer, 0, -1)
+    if lnum and lnum > 0 then
+      pcall(
+        vim.api.nvim_buf_add_highlight,
+        bufnr,
+        ns_previewer,
+        "TelescopePreviewLine",
+        lnum - 1,
+        0,
+        -1
+      )
+      pcall(vim.api.nvim_win_set_cursor, self.state.winid, {lnum, 0})
+      vim.api.nvim_buf_call(
+        bufnr,
+        function()
+          vim.cmd "norm! zz"
+        end
+      )
+    end
+  end
+
+  local do_forward_jump = function()
+    if jump_state ~= nil and #jump_state.diff_rows > 0 then
+      jump_state.cur =
+        utils.iff(
+        (jump_state.cur + 1) <= #jump_state.diff_rows,
+        jump_state.cur + 1,
+        #jump_state.diff_rows
+      )
+      jump_to_line(
+        jump_state.self,
+        jump_state.self.state.bufnr,
+        jump_state.diff_rows[jump_state.cur]
+      )
+    end
+  end
+
+  local do_reverse_jump = function()
+    if jump_state ~= nil and #jump_state.diff_rows > 0 then
+      jump_state.cur = utils.iff((jump_state.cur - 1) > 0, jump_state.cur - 1, 1)
+      jump_to_line(
+        jump_state.self,
+        jump_state.self.state.bufnr,
+        jump_state.diff_rows[jump_state.cur]
+      )
+    end
+  end
+
+  pickers.new(
+    {},
+    {
+      prompt_title = "File History",
+      previewer = previewers.new_buffer_previewer(
+        {
+          define_preview = function(self, entry)
+            jump_state = nil
+            if entry.index < #entries then
+              local previous_lines = entries[entry.index + 1].lines
+              local buffer_lines, diff_rows =
+                apply_diff_to_lines(
+                diff_strings(
+                  table.concat(previous_lines, line_ending),
+                  table.concat(entry.value.lines, line_ending)
+                ),
+                previous_lines
+              )
+              previous_lines = nil
+
+              vim.api.nvim_buf_set_lines(self.state.bufnr, 0, -1, false, buffer_lines)
+              putils.regex_highlighter(self.state.bufnr, "diff")
+
+              jump_state = {self = self, cur = 0, diff_rows = diff_rows}
+              vim.schedule(
+                function()
+                  do_forward_jump()
+                end
+              )
+            else
+              vim.api.nvim_buf_set_lines(self.state.bufnr, 0, -1, false, entry.value.lines)
+              putils.highlighter(self.state.bufnr, entry.value.ft, {})
+            end
+          end
+        }
+      ),
+      sorter = conf.generic_sorter({}),
+      finder = finders.new_table(
+        {
+          results = entries,
+          entry_maker = function(item)
+            return {
+              value = item,
+              ordinal = tostring(item.date),
+              display = os.date("%m-%d-%Y %H:%M:%S", item.date)
+            }
+          end
+        }
+      ),
+      attach_mappings = function(prompt_bufnr, map)
+        actions.select_default:replace(
+          function()
+            actions.close(prompt_bufnr)
+            local selection = action_state.get_selected_entry()
+            if selection ~= nil then
+              vim.api.nvim_buf_set_lines(0, 0, -1, false, selection.value.lines)
+            end
+          end
+        )
+        map("i", "<c-l>", do_forward_jump)
+        map("n", "<c-l>", do_forward_jump)
+        map("i", "<c-h>", do_reverse_jump)
+        map("n", "<c-h>", do_reverse_jump)
+        return true
+      end
+    }
+  ):find()
+end
+
+M.setup = function(config)
+  if config == nil then
+    config = {}
+  end
+
+  if config.exclusions ~= nil then
+    for _, e in pairs(config.exclusions) do
+      if type(e) ~= "function" then
+        print_message(
+          "'exlcusions' contains an entry that is not a function. Skipping all exclusions until this is corrected:"
+        )
+        utils.dump_table(e)
+        break
+      end
+      table.insert(haven_config.exclusions, e)
+    end
+  end
+  haven_config.enabled = vim.F.if_nil(config.enabled, haven_config.enabled)
+  haven_config.haven_path = vim.F.if_nil(config.haven_path, haven_config.haven_path)
+
+  if config.inclusions ~= nil then
+    for _, e in pairs(config.inclusions) do
+      if type(e) ~= "function" then
+        print_message(
+          "'inclusions' contains an entry that is not a function. Skipping this inclusion until it is corrected:"
+        )
+        utils.dump_table(e)
+      end
+      table.insert(haven_config.inclusions, e)
+    end
+  end
+
+  haven_config.max_history_count =
+    vim.F.if_nil(config.max_history_count, haven_config.max_history_count)
+  if haven_config.max_history_count < 10 then
+    print_message("'max_history_count' too low: " .. haven_config.max_history_count)
+    haven_config.max_history_count = 100
+    print_message("reset 'max_history_count': " .. haven_config.max_history_count)
+  elseif haven_config.max_history_count > 500 then
+    print_message("'max_history_count' too high: " .. haven_config.max_history_count)
+    haven_config.max_history_count = 500
+    print_message("reset 'max_history_count': " .. haven_config.max_history_count)
+  end
+
+  haven_config.save_timeout = vim.F.if_nil(config.save_timeout, haven_config.save_timeout)
+  if haven_config.save_timeout < 135 then
+    print_message("'save_timeout' too low: " .. haven_config.save_timeout)
+    haven_config.save_timeout = 135
+    print_message("reset 'save_timeout': " .. haven_config.save_timeout)
+  elseif haven_config.save_timeout > 10000 then
+    print_message("'save_timeout' too high: " .. haven_config.save_timeout)
+    haven_config.save_timeout = 10000
+    print_message("reset 'save_timeout': " .. haven_config.save_timeout)
+  end
+
+  if vim.fn.mkdir(haven_config.haven_path, "p") == 0 then
+    print_message("directory create failed: " .. haven_config.haven_path)
+    haven_config.enabled = false
+    return
+  end
+
+  if vim.fn.isdirectory(haven_config.haven_path) == 0 then
+    print_message("directory not found: " .. haven_config.haven_path)
+    haven_config.enabled = false
+    return
+  end
+
+  setup_autocmds()
+end
+
+M.disable = function()
+  if haven_config.enabled then
+    haven_config.enabled = false
+    setup_autocmds()
+  end
+end
+
+M.enable = function()
+  if not haven_config.enabled then
+    haven_config.enabled = true
+    handle_buffer_changed()
+    setup_autocmds()
+  end
+end
+
+M.history = function(bufname)
+  bufname = vim.F.if_nil(bufname, vim.fn.bufname())
+  local buf_info = vim.fn.getbufinfo(bufname)
+  if buf_info ~= nil and #buf_info > 0 then
+    buf_info = buf_info[1]
+    local save_file = create_save_file(buf_info)
+    if vim.fn.filereadable(save_file) ~= 0 then
+      local entries, err = read_change_file(buf_info, save_file)
+      if entries == nil then
+        print_message(err)
+        return
+      end
+
+      show_picker(table.reverse(entries))
+    end
+  end
+end
+
+_G.Nvim_Haven_Disable = M.disable
+_G.Nvim_Haven_Enable = M.enable
+_G.Nvim_Haven_History = M.history
+
+return M
diff --git a/lua/nvim-haven/utils/init.lua b/lua/nvim-haven/utils/init.lua
new file mode 100644
index 0000000..1ad4b05
--- /dev/null
+++ b/lua/nvim-haven/utils/init.lua
@@ -0,0 +1,58 @@
+local M = {}
+
+function string:ends_with(suffix)
+  return suffix == "" or self:sub(-(#suffix)) == suffix
+end
+
+function string:split(sep)
+  sep = sep or ":"
+  local fields = {}
+  local pattern = string.format("([^%s]+)", sep)
+  _ =
+    self:gsub(
+    pattern,
+    function(c)
+      fields[#fields + 1] = c
+    end
+  )
+  return fields
+end
+
+function string:starts_with(prefix)
+  return self:sub(1, #prefix) == prefix
+end
+
+function table.reverse(self)
+  local n = #self
+  local i = 1
+  while i < n do
+    self[i], self[n] = self[n], self[i]
+    i = i + 1
+    n = n - 1
+  end
+  return self
+end
+
+function M.iff(b, l, r)
+  if b then
+    return l
+  end
+
+  return r
+end
+
+M.is_windows = vim.fn.has("win32") == 1 or vim.fn.has("win64") == 1
+M.directory_sep = M.iff(M.is_windows, "\\\\", "/")
+M.not_directory_sep = M.iff(M.is_windows, "/", "\\\\")
+
+function M.create_path(...)
+  local Path = require "plenary.path"
+  local ret =
+    Path:new({...}):absolute():gsub(M.not_directory_sep, M.directory_sep):gsub(
+    M.directory_sep .. M.directory_sep,
+    M.directory_sep
+  )
+  return ret
+end
+
+return M
diff --git a/plugin/nvim-haven.lua b/plugin/nvim-haven.lua
new file mode 100644
index 0000000..6c216df
--- /dev/null
+++ b/plugin/nvim-haven.lua
@@ -0,0 +1,4 @@
+if vim.g.loaded_nvim_haven == 1 then
+  return
+end
+vim.g.loaded_nvim_haven = 1