fix: account for folds when computing visible range

## Details

Issue: #138

After the change to only parse text visible in the view port we
essentially broke for users who use folds. This is because the range
calculation only used the size of the window and the start.

This change iterates through the rows and determines if they are hidden
by a fold. Otherwise the logic is mostly the same except using lines
that are not folded instead of just the lines.

Author: MeanderingProgrammer

Diff for: CHANGELOG.md

@@ -14,6 +14,12 @@
 - wiki links nested in tables [72688ba](https://github.com/MeanderingProgrammer/render-markdown.nvim/commit/72688baea4ef0ed605033bf654b54d801b6a5f01)
 - code block background when indented in lists [#133](https://github.com/MeanderingProgrammer/render-markdown.nvim/issues/133)
   [4c823b1](https://github.com/MeanderingProgrammer/render-markdown.nvim/commit/4c823b1df151dbf1ed3ddaacac517be606b1e145)
+- do not set noref in vim.deepcopy [#139](https://github.com/MeanderingProgrammer/render-markdown.nvim/pull/139)
+- gate virt_text_repeat_linebreak to neovim >= 0.10.0 [98f9965](https://github.com/MeanderingProgrammer/render-markdown.nvim/commit/98f996563591b753470942165d2d5134df868529)
+
+### Collaborator Shoutouts
+
+- @P1roks
 
 ## 6.1.0 (2024-08-11)
 

Diff for: lua/render-markdown/context.lua

@@ -19,16 +19,31 @@ function Context.new(buf, win, offset)
     local self = setmetatable({}, Context)
     self.buf = buf
     self.win = win
-    local top = vim.api.nvim_win_call(win, vim.fn.winsaveview).topline - 1
-    local height = vim.api.nvim_win_get_height(win)
-    local lines = vim.api.nvim_buf_line_count(buf)
+    local top = util.view(win).topline - 1
     self.top = math.max(top - offset, 0)
-    self.bottom = math.min(top + height + offset, lines)
+    self.bottom = self:compute_bottom(top, offset)
     self.conceal = nil
     self.links = {}
     return self
 end
 
+---@private
+---@param top integer
+---@param offset integer
+---@return integer
+function Context:compute_bottom(top, offset)
+    local bottom = top
+    local lines = vim.api.nvim_buf_line_count(self.buf)
+    local target = vim.api.nvim_win_get_height(self.win) + offset
+    while bottom < lines and target > 0 do
+        bottom = bottom + 1
+        if util.visible(self.win, bottom) then
+            target = target - 1
+        end
+    end
+    return bottom
+end
+
 ---@param info render.md.NodeInfo
 ---@param amount integer
 function Context:add_offset(info, amount)

Diff for: lua/render-markdown/health.lua

@@ -5,7 +5,7 @@ local M = {}
 
 ---@private
 ---@type string
-M.version = '6.1.6'
+M.version = '6.1.7'
 
 function M.check()
     vim.health.start('render-markdown.nvim [version]')

Diff for: lua/render-markdown/ui.lua

@@ -103,7 +103,7 @@ function M.next_state(config, win)
     if not state.enabled then
         return 'default'
     end
-    if not util.get_leftcol(win) == 0 then
+    if not util.view(win).leftcol == 0 then
         return 'default'
     end
     if not vim.tbl_contains(config.render_modes, vim.fn.mode(true)) then

Diff for: lua/render-markdown/util.lua

@@ -43,10 +43,17 @@ function M.get_buf(buf, name)
 end
 
 ---@param win integer
----@return integer
-function M.get_leftcol(win)
+---@return vim.fn.winsaveview.ret
+function M.view(win)
+    return vim.api.nvim_win_call(win, vim.fn.winsaveview)
+end
+
+---@param win integer
+---@param row integer
+---@return boolean
+function M.visible(win, row)
     return vim.api.nvim_win_call(win, function()
-        return vim.fn.winsaveview().leftcol
+        return vim.fn.foldclosed(row) == -1
     end)
 end