local fn = vim.fn
local api = vim.api
local keymap = vim.keymap
local lsp = vim.lsp
local diagnostic = vim.diagnostic
local lspconfig = require("lspconfig")

local utils = require("utils")

-- set quickfix list from diagnostics in a certain buffer, not the whole workspace
local set_qflist = function(buf_num, severity)
  local diagnostics = nil
  diagnostics = diagnostic.get(buf_num, { severity = severity })

  local qf_items = diagnostic.toqflist(diagnostics)
  vim.fn.setqflist({}, " ", { title = "Diagnostics", items = qf_items })

  -- open quickfix by default
  vim.cmd([[copen]])
end

local custom_attach = function(client, bufnr)
  -- Mappings.
  local map = function(mode, l, r, opts)
    opts = opts or {}
    opts.silent = true
    opts.buffer = bufnr
    keymap.set(mode, l, r, opts)
  end

  map("n", "gd", vim.lsp.buf.definition, { desc = "go to definition" })
  map("n", "<C-]>", vim.lsp.buf.definition)
  map("n", "K", vim.lsp.buf.hover)
  map("n", "<C-k>", vim.lsp.buf.signature_help)
  map("n", "<space>rn", vim.lsp.buf.rename, { desc = "varialbe rename" })
  map("n", "gr", vim.lsp.buf.references, { desc = "show references" })
  map("n", "[d", diagnostic.goto_prev, { desc = "previous diagnostic" })
  map("n", "]d", diagnostic.goto_next, { desc = "next diagnostic" })
  -- this puts diagnostics from opened files to quickfix
  map("n", "<space>qw", diagnostic.setqflist, { desc = "put window diagnostics to qf" })
  -- this puts diagnostics from current buffer to quickfix
  map("n", "<space>qb", function()
    set_qflist(bufnr)
  end, { desc = "put buffer diagnostics to qf" })
  map("n", "<space>ca", vim.lsp.buf.code_action, { desc = "LSP code action" })
  map("n", "<space>wa", vim.lsp.buf.add_workspace_folder, { desc = "add workspace folder" })
  map("n", "<space>wr", vim.lsp.buf.remove_workspace_folder, { desc = "remove workspace folder" })
  map("n", "<space>wl", function()
    vim.print(vim.lsp.buf.list_workspace_folders())
  end, { desc = "list workspace folder" })

  -- Set some key bindings conditional on server capabilities
  if client.server_capabilities.documentFormattingProvider then
    map({ "n", "x" }, "<space>f", vim.lsp.buf.format, { desc = "format code" })
  end

  -- Uncomment code below to enable inlay hint from language server, some LSP server supports inlay hint,
  -- but disable this feature by default, so you may need to enable inlay hint in the LSP server config.
  -- vim.lsp.inlay_hint.enable(true, {buffer=bufnr})

  api.nvim_create_autocmd("CursorHold", {
    buffer = bufnr,
    callback = function()
      local float_opts = {
        focusable = false,
        close_events = { "BufLeave", "CursorMoved", "InsertEnter", "FocusLost" },
        border = "rounded",
        source = "always", -- show source in diagnostic popup window
        prefix = " ",
      }

      if not vim.b.diagnostics_pos then
        vim.b.diagnostics_pos = { nil, nil }
      end

      local cursor_pos = api.nvim_win_get_cursor(0)
      if
        (cursor_pos[1] ~= vim.b.diagnostics_pos[1] or cursor_pos[2] ~= vim.b.diagnostics_pos[2])
        and #diagnostic.get() > 0
      then
        diagnostic.open_float(nil, float_opts)
      end

      vim.b.diagnostics_pos = cursor_pos
    end,
  })

  -- The blow command will highlight the current variable and its usages in the buffer.
  if client.server_capabilities.documentHighlightProvider then
    vim.cmd([[
      hi! link LspReferenceRead Visual
      hi! link LspReferenceText Visual
      hi! link LspReferenceWrite Visual
    ]])

    local gid = api.nvim_create_augroup("lsp_document_highlight", { clear = true })
    api.nvim_create_autocmd("CursorHold", {
      group = gid,
      buffer = bufnr,
      callback = function()
        lsp.buf.document_highlight()
      end,
    })

    api.nvim_create_autocmd("CursorMoved", {
      group = gid,
      buffer = bufnr,
      callback = function()
        lsp.buf.clear_references()
      end,
    })
  end

  if vim.g.logging_level == "debug" then
    local msg = string.format("Language server %s started!", client.name)
    vim.notify(msg, vim.log.levels.DEBUG, { title = "Nvim-config" })
  end
end

local capabilities = require("cmp_nvim_lsp").default_capabilities()

-- required by nvim-ufo
capabilities.textDocument.foldingRange = {
  dynamicRegistration = false,
  lineFoldingOnly = true,
}

-- For what diagnostic is enabled in which type checking mode, check doc:
-- https://github.com/microsoft/pyright/blob/main/docs/configuration.md#diagnostic-settings-defaults
-- Currently, the pyright also has some issues displaying hover documentation:
-- https://www.reddit.com/r/neovim/comments/1gdv1rc/what_is_causeing_the_lsp_hover_docs_to_looks_like/

if utils.executable("pyright") then
  local new_capability = {
    -- this will remove some of the diagnostics that duplicates those from ruff, idea taken and adapted from
    -- here: https://github.com/astral-sh/ruff-lsp/issues/384#issuecomment-1989619482
    textDocument = {
      publishDiagnostics = {
        tagSupport = {
          valueSet = { 2 },
        },
      },
      hover = {
        contentFormat = { "plaintext" },
        dynamicRegistration = true,
      },
    },
  }
  local merged_capability = vim.tbl_deep_extend("force", capabilities, new_capability)

  lspconfig.pyright.setup {
    cmd = { "delance-langserver", "--stdio" },
    on_attach = custom_attach,
    capabilities = merged_capability,
    settings = {
      pyright = {
        -- disable import sorting and use Ruff for this
        disableOrganizeImports = true,
        disableTaggedHints = false,
      },
      python = {
        analysis = {
          autoSearchPaths = true,
          diagnosticMode = "workspace",
          typeCheckingMode = "standard",
          useLibraryCodeForTypes = true,
          -- we can this setting below to redefine some diagnostics
          diagnosticSeverityOverrides = {
            deprecateTypingAliases = false,
          },
          -- inlay hint settings are provided by pylance?
          inlayHints = {
            callArgumentNames = "partial",
            functionReturnTypes = true,
            pytestParameters = true,
            variableTypes = true,
          },
        },
      },
    },
  }
else
  vim.notify("pyright not found!", vim.log.levels.WARN, { title = "Nvim-config" })
end

if utils.executable("ruff") then
  require("lspconfig").ruff.setup {
    on_attach = custom_attach,
    capabilities = capabilities,
    init_options = {
      -- the settings can be found here: https://docs.astral.sh/ruff/editors/settings/
      settings = {
        organizeImports = true,
      },
    },
  }
end

-- Disable ruff hover feature in favor of Pyright
vim.api.nvim_create_autocmd("LspAttach", {
  group = vim.api.nvim_create_augroup("lsp_attach_disable_ruff_hover", { clear = true }),
  callback = function(args)
    local client = vim.lsp.get_client_by_id(args.data.client_id)
    -- vim.print(client.name, client.server_capabilities)

    if client == nil then
      return
    end
    if client.name == "ruff" then
      client.server_capabilities.hoverProvider = false
    end
  end,
  desc = "LSP: Disable hover capability from Ruff",
})

if utils.executable("ltex-ls") then
  lspconfig.ltex.setup {
    on_attach = custom_attach,
    cmd = { "ltex-ls" },
    filetypes = { "text", "plaintex", "tex", "markdown" },
    settings = {
      ltex = {
        language = "en",
      },
    },
    flags = { debounce_text_changes = 300 },
  }
end

if utils.executable("clangd") then
  lspconfig.clangd.setup {
    on_attach = custom_attach,
    capabilities = capabilities,
    filetypes = { "c", "cpp", "cc" },
    flags = {
      debounce_text_changes = 500,
    },
  }
end

-- set up vim-language-server
if utils.executable("vim-language-server") then
  lspconfig.vimls.setup {
    on_attach = custom_attach,
    flags = {
      debounce_text_changes = 500,
    },
    capabilities = capabilities,
  }
else
  vim.notify("vim-language-server not found!", vim.log.levels.WARN, { title = "Nvim-config" })
end

-- set up bash-language-server
if utils.executable("bash-language-server") then
  lspconfig.bashls.setup {
    on_attach = custom_attach,
    capabilities = capabilities,
  }
end

-- settings for lua-language-server can be found on https://luals.github.io/wiki/settings/
if utils.executable("lua-language-server") then
  lspconfig.lua_ls.setup {
    on_attach = custom_attach,
    settings = {
      Lua = {
        runtime = {
          -- Tell the language server which version of Lua you're using (most likely LuaJIT in the case of Neovim)
          version = "LuaJIT",
        },
        hint = {
          enable = true,
        },
      },
    },
    capabilities = capabilities,
  }
end

-- Change diagnostic signs.
fn.sign_define("DiagnosticSignError", { text = "🆇", texthl = "DiagnosticSignError" })
fn.sign_define("DiagnosticSignWarn", { text = "⚠️", texthl = "DiagnosticSignWarn" })
fn.sign_define("DiagnosticSignInfo", { text = "ℹ️", texthl = "DiagnosticSignInfo" })
fn.sign_define("DiagnosticSignHint", { text = "", texthl = "DiagnosticSignHint" })

-- global config for diagnostic
diagnostic.config {
  underline = false,
  virtual_text = false,
  signs = true,
  severity_sort = true,
}

-- lsp.handlers["textDocument/publishDiagnostics"] = lsp.with(lsp.diagnostic.on_publish_diagnostics, {
--   underline = false,
--   virtual_text = false,
--   signs = true,
--   update_in_insert = false,
-- })

-- Change border of documentation hover window, See https://github.com/neovim/neovim/pull/13998.
lsp.handlers["textDocument/hover"] = lsp.with(vim.lsp.handlers.hover, {
  border = "rounded",
})