Added support for relative date (#67)

* Updated format to support relative date

* Updated readme

* Updated return value

Author: mainendra

README.md

@@ -80,7 +80,7 @@ Default config:
 ```
 
 These are the fields you can configure by passing them to the `require('blame').setup({})` function:
-- `date_format` - string - Pattern for the date
+- `date_format` - string - Pattern for the date, '%r' for relative date
 - `virtual_style` - "right_align" or "float" - Float moves the virtual text close to the content of the file.
 - `views` - views that can be used when toggling blame
 - `focus_blame` - boolean - Focus on the blame window when it's opened as well as blame stack push/pop

lua/blame/blame_stack.lua

@@ -188,7 +188,7 @@ function BlameStack:open_stack_info_float()
                     .. " "
                     .. v.author
                     .. " "
-                    .. os.date(self.config.date_format, v.committer_time)
+                    .. utils.format_time(self.config.date_format, v.committer_time)
             )
         end
         vim.api.nvim_buf_set_lines(info_buf, 0, -1, false, lines_text)
@@ -222,7 +222,7 @@ function BlameStack:open_stack_info_float()
                 .. " "
                 .. v.author
                 .. " "
-                .. os.date(self.config.date_format, v.committer_time)
+                .. utils.format_time(self.config.date_format, v.committer_time)
         )
     end
     vim.api.nvim_buf_set_lines(info_buf, 0, -1, false, lines_text)

lua/blame/formats/default_formats.lua

@@ -1,3 +1,4 @@
+local utils = require("blame.utils")
 local M = {}
 
 ---@type FormatFn
@@ -14,7 +15,7 @@ M.commit_date_author_fn = function(line_porcelain, config, idx)
                     hl = "Comment",
                 },
                 {
-                    textValue = os.date(
+                    textValue = utils.format_time(
                         config.date_format,
                         line_porcelain.committer_time
                     ),
@@ -62,7 +63,7 @@ M.date_message = function(line_porcelain, config, idx)
             idx = idx,
             values = {
                 {
-                    textValue = os.date(
+                    textValue = utils.format_time(
                         config.date_format,
                         line_porcelain.committer_time
                     ),

lua/blame/utils.lua

@@ -1,5 +1,28 @@
 local M = {}
 
+local function relative_time(timestamp)
+    local diff = os.time() - timestamp
+
+    if diff < 60 then
+        return diff .. " second" .. (diff ~= 1 and "s" or "") .. " ago"
+    elseif diff < 3600 then
+        local minutes = math.floor(diff / 60)
+        return minutes .. " minute" .. (minutes ~= 1 and "s" or "") .. " ago"
+    elseif diff < 86400 then
+        local hours = math.floor(diff / 3600)
+        return hours .. " hour" .. (hours ~= 1 and "s" or "") .. " ago"
+    elseif diff < 2592000 then
+        local days = math.floor(diff / 86400)
+        return days .. " day" .. (days ~= 1 and "s" or "") .. " ago"
+    elseif diff < 31536000 then
+        local months = math.floor(diff / 2592000)
+        return months .. " month" .. (months ~= 1 and "s" or "") .. " ago"
+    else
+        local years = math.floor(diff / 31536000)
+        return years .. " year" .. (years ~= 1 and "s" or "") .. " ago"
+    end
+end
+
 ---Calculates the longest string in the string[]
 ---@param string_array string[]
 ---@return integer
@@ -13,4 +36,19 @@ M.longest_string_in_array = function(string_array)
     return longest
 end
 
+--- Formats a timestamp using a format string.
+--- If the format contains "%r", it will be replaced with a human-readable relative time.
+--- Otherwise, it behaves like os.date.
+---
+--- @param format string: A format string (e.g. "%r", "%Y-%m-%d", "Committed %r")
+--- @param timestamp number: A UNIX timestamp to format
+--- @return string: Formatted date string
+M.format_time = function(format, timestamp)
+    if format:find("%%r") then
+        return (format:gsub("%%r", relative_time(timestamp)))
+    else
+        return tostring(os.date(format, timestamp))
+    end
+end
+
 return M