From 80a7839eec62560e9160663cee4ea4c9e67196fc Mon Sep 17 00:00:00 2001
From: Folke Lemaitre <folke.lemaitre@gmail.com>
Date: Thu, 15 Dec 2022 00:22:40 +0100
Subject: [PATCH] feat: lua code generator for the README.md

---
 lua/lazy/docs.lua | 76 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 76 insertions(+)
 create mode 100644 lua/lazy/docs.lua

diff --git a/lua/lazy/docs.lua b/lua/lazy/docs.lua
new file mode 100644
index 0000000..1d20f69
--- /dev/null
+++ b/lua/lazy/docs.lua
@@ -0,0 +1,76 @@
+local M = {}
+
+function M.read(file)
+  local fd = assert(io.open(file, "r"))
+  local data = fd:read("*a") ---@type string
+  fd:close()
+  return data
+end
+
+function M.indent(str, indent)
+  local lines = vim.split(str, "\n")
+  for l, line in ipairs(lines) do
+    lines[l] = (" "):rep(indent) .. line
+  end
+  return table.concat(lines, "\n")
+end
+
+---@param str string
+function M.fix_indent(str)
+  local lines = vim.split(str, "\n")
+
+  local width = 120
+  for _, line in ipairs(lines) do
+    width = math.min(width, #line:match("^%s*"))
+  end
+
+  for l, line in ipairs(lines) do
+    lines[l] = line:sub(width)
+  end
+  return table.concat(lines, "\n")
+end
+
+---@param contents table<string, string>
+function M.save(contents)
+  local readme = M.read("README.md")
+  for tag, content in pairs(contents) do
+    content = M.fix_indent(content)
+    content = content:gsub("%%", "%%%%")
+    content = vim.trim(content)
+    local pattern = "(<%!%-%- " .. tag .. "_start %-%->).*(<%!%-%- " .. tag .. "_end %-%->)"
+    if not readme:find(pattern) then
+      error("tag " .. tag .. " not found")
+    end
+    readme = readme:gsub(pattern, "%1\n\n```lua\n" .. content .. "\n```\n\n%2")
+  end
+
+  local fd = assert(io.open("README.md", "w+"))
+  fd:write(readme)
+  fd:close()
+end
+
+---@return string
+function M.extract(file, pattern)
+  local init = M.read(file)
+  return assert(init:match(pattern))
+end
+
+function M.update()
+  local cache_config = M.extract("lua/lazy/core/cache.lua", "\nM%.config = ({.-\n})")
+  local config = M.extract("lua/lazy/core/config.lua", "\nM%.defaults = ({.-\n})")
+  config = config:gsub(
+    "\n%s*%-%-%-@type LazyCacheConfig.*cache = nil,",
+    "\n" .. M.indent("cache = " .. cache_config .. ",", 4)
+  )
+  config = config:gsub("%s*debug = false.\n", "\n")
+  M.save({
+    bootstrap = M.extract("lua/lazy/init.lua", "function M%.bootstrap%(%)\n(.-)\nend"),
+    config = config,
+    spec = M.read("lua/lazy/example.lua"),
+  })
+  vim.cmd.checktime()
+end
+
+M.update()
+
+return M