add flag to enable telescope preview and to choose picker (#97)

* Flags to enable telescope preview and to choose picker

* 4 spaces -> 2 space lua

* changes to align with repo code-style

vim/autoload/himalaya/mbox.lua

@@ -1,46 +0,0 @@
-local actions = require('telescope.actions')
-local action_state = require('telescope.actions.state')
-local finders = require('telescope.finders')
-local pickers = require('telescope.pickers')
-local sorters = require('telescope.sorters')
-local previewers = require('telescope.previewers')
-
-function mbox_picker(mboxes)
-  pickers.new {
-    results_title = 'Mailboxes',
-    finder = finders.new_table {
-        results = mboxes,
-        entry_maker = function(entry)
-            return {
-                value = entry,
-                display = entry,
-                ordinal = entry,
-                preview_command = function(entry, bufnr)
-                    vim.api.nvim_buf_call(bufnr, function()
-                        local page = 0 -- page 0 for preview
-                        local success, output = pcall(vim.fn['himalaya#msg#list_with'], entry.value, page, true)
-                        if not (success) then
-                            vim.cmd('redraw')
-                            vim.bo.modifiable = true
-                            local errors = vim.fn.split(output, '\n')
-                            errors[1] = "Errors: "..errors[1]
-                            vim.api.nvim_buf_set_lines(bufnr, 0, -1, true, errors)
-                        end
-                    end)
-                end
-            }
-      end,
-    },
-    sorter = sorters.fuzzy_with_index_bias(),
-    attach_mappings = function(prompt_bufnr)
-      actions.select_default:replace(function()
-        local selection = action_state.get_selected_entry()
-        actions.close(prompt_bufnr)
-        vim.fn['himalaya#mbox#post_input'](selection.display)
-      end)
-
-      return true
-    end,
-    previewer = previewers.display_content.new({})
-  }:find()
-end

vim/autoload/himalaya/mbox.vim

@@ -25,27 +25,44 @@ function! himalaya#mbox#curr_mbox()
   return s:curr_mbox
 endfunction
 
+function! s:telescope_picker(mboxes)
+  call luaeval('require("himalaya.mbox").mbox_picker')(a:mboxes)
+endfunction
+
+function! s:fzf_picker(mboxes)
+  call fzf#run({
+    \"source": a:mboxes,
+    \"sink": function("himalaya#mbox#post_input"),
+    \"down": "25%",
+  \})
+endfunction
+
+function! s:native_picker(mboxes)
+  let choice = map(copy(a:mboxes), "printf('%s (%d)', v:val, v:key)")
+  let choice = input(join(choice, ", ") . ": ")
+  redraw | echo
+  call himalaya#mbox#post_input(a:mboxes[choice])
+endfunction
+
+let s:pickers = {"telescope": function("s:telescope_picker"), "fzf": function("s:fzf_picker"), "native": function("s:native_picker")}
+
 function! himalaya#mbox#input()
   try
     let mboxes = map(s:cli("mailboxes", [], "Fetching mailboxes", 0), "v:val.name")
 
-    if &rtp =~ "telescope"
-      execute printf("luafile %s/mbox.lua", s:dir)
-      call luaeval(printf("mbox_picker({%s})", join(map(mboxes, "string(v:val)"), ", ")))
-
-    elseif &rtp =~ "fzf"
-      call fzf#run({
-        \"source": mboxes,
-        \"sink": function("himalaya#mbox#post_input"),
-        \"down": "25%",
-      \})
-
+    if exists("g:himalaya_mailbox_picker") " Get user choice for picker, otherwise check runtimepath
+      let mbox_picker = g:himalaya_mailbox_picker
     else
-      let choice = map(copy(mboxes), "printf('%s (%d)', v:val, v:key)")
-      let choice = input(join(choice, ", ") . ": ")
-      redraw | echo
-      call himalaya#mbox#post_input(mboxes[choice])
+      if &rtp =~ "telescope"
+        let mbox_picker = "telescope"
+      elseif &rtp =~ "fzf"
+        let mbox_picker = "fzf"
+      else
+        let mbox_picker = "native"
       endif
+    endif
+
+    call s:pickers[mbox_picker](mboxes)
   catch
     if !empty(v:exception)
       redraw | call himalaya#shared#log#err(v:exception)

vim/lua/himalaya/mbox.lua

@@ -0,0 +1,57 @@
+local M = {}
+
+local actions = require('telescope.actions')
+local action_state = require('telescope.actions.state')
+local finders = require('telescope.finders')
+local pickers = require('telescope.pickers')
+local sorters = require('telescope.sorters')
+local previewers = require('telescope.previewers')
+
+local function preview_command(entry, bufnr)
+  vim.api.nvim_buf_call(bufnr, function()
+    local page = 0 -- page 0 for preview
+    local success, output = pcall(vim.fn['himalaya#msg#list_with'], entry.value, page, true)
+    if not (success) then
+      vim.cmd('redraw')
+      vim.bo.modifiable = true
+      local errors = vim.fn.split(output, '\n')
+      errors[1] = "Errors: "..errors[1]
+      vim.api.nvim_buf_set_lines(bufnr, 0, -1, true, errors)
+    end
+  end)
+end
+
+local function entry_maker(entry)
+  return {
+    value = entry,
+    display = entry,
+    ordinal = entry,
+    preview_command = preview_command,
+  }
+end
+
+M.mbox_picker = function(mboxes)
+  local finder_opts = {results = mboxes}
+  local previewer = nil
+  if vim.g.himalaya_telescope_preview_enabled then
+    finder_opts.entry_maker = entry_maker
+    previewer = previewers.display_content.new({})
+  end
+  pickers.new {
+    results_title = 'Mailboxes',
+    finder = finders.new_table(finder_opts),
+    sorter = sorters.fuzzy_with_index_bias(),
+    attach_mappings = function(prompt_bufnr)
+      actions.select_default:replace(function()
+        local selection = action_state.get_selected_entry()
+        actions.close(prompt_bufnr)
+        vim.fn['himalaya#mbox#post_input'](selection.display)
+      end)
+
+      return true
+    end,
+    previewer = previewer,
+  }:find()
+end
+
+return M