feat: add linter config and clean up codebase

lua/lsp/linter.lua

@@ -0,0 +1,163 @@
+local utils = require("utils")
+
+---@class Linter
+---@field name string
+---@field namespace number
+---@field augroup number
+---@field buffers number[]
+---@field config LinterConfig
+M = {}
+M.__index = M
+
+---@alias Group
+---| "lnum"
+---| "col"
+---| "severity"
+---| "message"
+
+---@class LinterConfig
+---@field cmd string[]
+---@field stdin? boolean
+---@field stdout? boolean
+---@field stderr? boolean
+---@field pattern string
+---@field groups Group[]
+---@field severity_map table<string, vim.diagnostic.Severity>
+---@field source? string
+---@field debounce? number
+M.config = {}
+
+function M.validate(name, config)
+    local ok, resp = pcall(vim.validate, {
+        name = { name, "string" },
+        config = { config, "table" },
+    })
+
+    if ok then
+        ok, resp = pcall(vim.validate, {
+            cmd = {
+                config.cmd,
+                function(t)
+                    return utils.is_list(t, "string")
+                end,
+                "list of strings",
+            },
+            stdin = { config.stdin, "boolean", true },
+            stdout = { config.stdout, "boolean", true },
+            stderr = { config.stderr, "boolean", true },
+            pattern = { config.pattern, "string" },
+            groups = {
+                config.groups,
+                function(t)
+                    return utils.is_list(t, "string")
+                end,
+                "list of strings",
+            },
+            severity_map = {
+                config.severity_map,
+                function(t)
+                    return utils.is_map(t, "string", "number")
+                end,
+                "map of string and number",
+            },
+            debounce = { config.debounce, "number", true },
+            source = { config.source, "string", true },
+        })
+    end
+
+    if not ok then
+        utils.err(("Invalid config for linter:\n%s"):format(resp))
+        return false
+    end
+
+    return true
+end
+
+function M:run(bufnr)
+    local input
+    -- TODO: add placeholder variables for when not using stdin
+    if self.config.stdin then
+        input = vim.api.nvim_buf_get_lines(bufnr, 0, -1, false)
+    end
+
+    vim.system(
+        self.config.cmd,
+        { stdin = input },
+        vim.schedule_wrap(function(out)
+            local output
+            if self.config.stdout then
+                output = out.stdout or ""
+            end
+            if self.config.stderr then
+                output = out.stderr or ""
+            end
+
+            local output_lines = vim.fn.split(output, "\n", false)
+            local diagnostics = {}
+            for _, line in ipairs(output_lines) do
+                local ok, resp = pcall(
+                    vim.diagnostic.match,
+                    line,
+                    self.config.pattern,
+                    self.config.groups,
+                    self.config.severity_map
+                )
+                if not ok then
+                    utils.err(tostring(resp))
+                    return
+                elseif not resp then
+                    utils.err(("Failed to parse linter output:\n%s"):format(line))
+                end
+
+                resp.source = self.config.source
+                table.insert(diagnostics, resp)
+            end
+            vim.diagnostic.set(self.namespace, bufnr, diagnostics)
+        end)
+    )
+end
+
+function M:init(bufnr)
+    table.insert(self.buffers, bufnr)
+    vim.api.nvim_create_autocmd({ "TextChanged", "TextChangedI" }, {
+        buffer = bufnr,
+        callback = utils.debounce(function()
+            self:run(bufnr)
+        end, self.config.debounce),
+        group = self.augroup,
+    })
+    self:run(bufnr)
+end
+
+function M:deinit()
+    for _, bufnr in ipairs(self.buffers) do
+        vim.api.nvim_buf_clear_namespace(bufnr, self.namespace, 0, -1)
+    end
+    self.buffers = {}
+
+    vim.api.nvim_clear_autocmds({ group = self.augroup })
+end
+
+--- Create a new instance
+---@param name string
+---@param config LinterConfig
+---@return Linter|nil
+function M.new(name, config)
+    if not M.validate(name, config) then
+        return
+    end
+
+    config.debounce = config.debounce or 100
+
+    local linter = {
+        name = name,
+        namespace = vim.api.nvim_create_namespace(name),
+        augroup = vim.api.nvim_create_augroup(name, {}),
+        buffers = {},
+        config = config,
+    }
+
+    return setmetatable(linter, M)
+end
+
+return M