feat(picker): added new icons picker for nerd fonts and emoji. Closes #703

lua/snacks/picker/source/icons.lua

@@ -0,0 +1,97 @@
+local M = {}
+
+---@type table<string, {url: string, v?:number, build: fun(data:table):snacks.picker.Icon[]}>
+M.sources = {
+  nerd_fonts = {
+    url = "https://github.com/ryanoasis/nerd-fonts/raw/refs/heads/master/glyphnames.json",
+    v = 3,
+    build = function(data)
+      ---@cast data table<string, {char:string, code:string}>
+      local ret = {} ---@type snacks.picker.Icon[]
+      for name, info in pairs(data) do
+        if name ~= "METADATA" then
+          local font, icon = name:match("^([%w_]+)%-(.*)$")
+          if not font then
+            error("Invalid icon name: " .. name)
+          end
+          table.insert(ret, {
+            name = icon,
+            icon = info.char,
+            source = "nerd font",
+            category = font,
+          })
+        end
+      end
+      return ret
+    end,
+  },
+  emoji = {
+    url = "https://raw.githubusercontent.com/muan/unicode-emoji-json/refs/heads/main/data-by-emoji.json",
+    v = 4,
+    build = function(data)
+      ---@cast data table<string, {name:string, slug:string, group:string}>
+      local ret = {} ---@type snacks.picker.Icon[]
+      for icon, info in pairs(data) do
+        table.insert(ret, {
+          name = info.name,
+          icon = icon,
+          source = "emoji",
+          category = info.group,
+        })
+      end
+      return ret
+    end,
+  },
+}
+
+---@class snacks.picker.Icon: snacks.picker.finder.Item
+---@field icon string
+---@field name string
+---@field source string
+---@field category string
+---@field desc? string
+
+---@param source_name string
+local function load(source_name)
+  local source = M.sources[source_name]
+  local file = vim.fn.stdpath("cache") .. "/snacks/picker/icons/" .. source_name .. "-v" .. (source.v or 1) .. ".json"
+  vim.fn.mkdir(vim.fn.fnamemodify(file, ":h"), "p")
+  if vim.fn.filereadable(file) == 1 then
+    local fd = assert(io.open(file, "r"))
+    local data = fd:read("*a")
+    fd:close()
+    return vim.json.decode(data) ---@type snacks.picker.Icon[]
+  end
+
+  Snacks.notify("Fetching `" .. source_name .. "` icons …")
+  if vim.fn.executable("curl") == 0 then
+    Snacks.notify.error("`curl` is required to fetch icons")
+    return {}
+  end
+  local out = vim.fn.system({ "curl", "-s", "-L", source.url })
+  if vim.v.shell_error ~= 0 then
+    Snacks.notify.error(out, { title = "Icons Picker" })
+    return {}
+  end
+  local icons = source.build(vim.json.decode(out))
+  local fd = assert(io.open(file, "w"))
+  fd:write(vim.json.encode(icons))
+  fd:close()
+  return icons
+end
+
+---@param opts snacks.picker.icons.Config
+---@type snacks.picker.finder
+function M.icons(opts)
+  local ret = {} ---@type snacks.picker.Icon[]
+  for _, source in ipairs(opts.icons or { "nerd_fonts", "emoji" }) do
+    vim.list_extend(ret, load(source))
+  end
+  for _, icon in ipairs(ret) do
+    icon.text = Snacks.picker.util.text(icon, { "source", "category", "name" })
+    icon.data = icon.icon
+  end
+  return ret
+end
+
+return M