local golist = require("go.list").list
local util = require("go.utils")
local log = util.log
local vfn = vim.fn
local api = vim.api

local path_to_pkg = {}
local complete = function()
  local ok, l = golist(false, { util.all_pkgs() })
  if not ok then
    log("Failed to find all packages for current module/project.")
  end
  local curpkgmatch = false
  local curpkg = vfn.fnamemodify(vfn.expand("%"), ":h:.")
  local pkgs = {}
  for _, p in ipairs(l) do
    local d = vfn.fnamemodify(p.Dir, ":.")
    if curpkg ~= d then
      if d ~= vfn.getcwd() then
        table.insert(pkgs, util.relative_to_cwd(d))
      end
    else
      curpkgmatch = true
    end
  end
  table.sort(pkgs)
  table.insert(pkgs, util.all_pkgs())
  table.insert(pkgs, ".")
  if curpkgmatch then
    table.insert(pkgs, util.relative_to_cwd(curpkg))
  end
  return table.concat(pkgs, "\n")
end

local all_pkgs = function()
  local ok, l = golist(false, { util.all_pkgs() })
  if not ok then
    log("Failed to find all packages for current module/project.")
  end
  return l
end

local pkg_from_path = function(pkg, bufnr)
  local cmd = { "go", "list" }
  if pkg ~= nil then
    table.insert(cmd, pkg)
  end
  log(cmd)
  return util.exec_in_path(cmd, bufnr)
end

local show_float = function(result)
  local textview = util.load_plugin("guihua.lua", "guihua.textview")
  if not textview then
    util.log("Failed to load guihua.textview")

    vim.fn.setloclist(0, {}, " ", {
      title = "go package outline",
      lines = result,
    })
    vim.cmd("lopen")
    return
  end
  local win = textview:new({
    relative = "cursor",
    syntax = "lua",
    rect = { height = math.min(40, #result), pos_x = 0, pos_y = 10 },
    data = result,
  })
  log("draw data", result)
  vim.api.nvim_buf_set_option(win.buf, "filetype", "go")
  return win:on_draw(result)
end

local defs
local render_outline = function(result)
  if not result then
    log("result nil", debug.traceback())
    return
  end
  local fname = vim.fn.tempname() .. "._go" -- avoid lsp activation
  log("tmp:" .. fname)
  local uri = vim.uri_from_fname(fname)
  local bufnr = vim.uri_to_bufnr(uri)
  vim.fn.writefile(result, fname)
  vfn.bufload(bufnr)
  defs = require("go.ts.utils").list_definitions_toc(bufnr)
  return bufnr, fname
end

local outline
local render
local show_panel = function(result, pkg, rerender)
  local bufnr, fname = render_outline(result)
  if rerender then
    return true -- just re-gen the outline
  end

  log("defs 1", defs[1])
  local panel = util.load_plugin("guihua.lua", "guihua.panel")
  local pkg_name = pkg or "pkg"
  pkg_name = vfn.split(pkg_name, "/")
  pkg_name = pkg_name[#pkg_name] or "pkg"
  log("create panel")
  if panel then
    local p = panel:new({
      header = "    " .. pkg_name .. "   ",
      render = function(b)
        log("render for ", bufnr, b)
        log(debug.traceback())
        -- outline("-r")
        render()
        return defs
      end,
      on_confirm = function(n)
        log("on_confirm symbol ", n)
        if not n or not n.symbol then
          log("info missing: symbol ", n)
          return
        end
        -- need to change to main window first to enable gopls
        local wins = api.nvim_list_wins()
        local panel_win = api.nvim_get_current_win()
        log(wins, panel_win)
        local cur_win
        for _, w in ipairs(wins) do
          if w ~= panel_win then
            api.nvim_set_current_win(w)
            local cur = api.nvim_win_get_cursor(w)
            api.nvim_win_set_cursor(w, cur)
            cur_win = w
            break
          end
        end

        vim.lsp.buf_request(0, "workspace/symbol", { query = "'" .. n.symbol }, function(e, result, ctx)
          local filtered = {}
          for _, r in pairs(result) do
            local container = r.containerName
            if pkg == container and r.name == n.symbol then
              table.insert(filtered, r)
            end
          end
          log("filtered", filtered)
          if #filtered == 0 then
            log("nothing found fallback to result", pkg, n.symbol)
            filtered = result
          end

          if vfn.empty(filtered) == 1 then
            log(e, result, ctx)
            vim.notify("no symbol found for " .. vim.inspect(pkg))
            return false
          end
          if #filtered == 1 then
            -- jump to pos
            local loc = filtered[1].location
            local buf = vim.uri_to_bufnr(loc.uri)
            vfn.bufload(buf)
            api.nvim_set_current_win(cur_win)
            api.nvim_set_current_buf(buf)
            api.nvim_win_set_buf(cur_win, buf)
            api.nvim_win_set_cursor(cur_win, { loc.range.start.line + 1, loc.range.start.character })
          else
            -- lets just call workspace/symbol handler
            vim.lsp.handlers["workspace/symbol"](e, filtered, ctx)
          end
        end)
        -- vim.lsp.buf.workspace_symbol("'" .. n.symbol)
        return n.symbol
      end,
    })
    p:open(true)
  else
    vim.fn.setloclist(0, {}, " ", {
      title = "go package outline",
      lines = defs,
    })
    vim.cmd("lopen")
  end
  log("cleanup")
  vim.api.nvim_buf_delete(bufnr, { unload = true })
  os.remove(fname)
end

local pkg_info = {}
-- get package info
local function handle_data_out(_, data, ev)
  data = util.handle_job_data(data)
  if not data then
    return
  end
  local types = { "CONSTANTS", "FUNCTIONS", "TYPES", "VARIABLES" }
  for i, val in ipairs(data) do
    -- first strip the filename
    if vim.tbl_contains(types, val) then
      val = "//" .. val
    end

    local sp = string.match(val, "^(%s*)")
    if sp and #sp == 4 then
      val = "//" .. val
    end
    local f = string.match(val, "^func ")
    if f then
      -- incase the func def is mulilines
      local next_line = data[i + 1]
      if next_line then
        local next_sp = string.match(next_line, "^(%s*)") -- one tab in front
        if next_sp and #next_sp == 1 then -- tab size 1
          next_line = next_line .. "{}"
          data[i + 1] = next_line
        else
          val = val .. "{}"
        end
      else
        val = val .. "{}"
      end
    end
    -- log(val)
    table.insert(pkg_info, val)
  end
end

local gen_pkg_info = function(cmd, pkg, arg, rerender)
  log("gen_pkg_info", cmd, pkg, rerender)
  vfn.jobstart(cmd, {
    on_stdout = handle_data_out,
    on_exit = function(e, data, _)
      if data ~= 0 then
        log("no packege info data " .. e .. tostring(data))
        return
      end
      if arg == "-f" then
        return show_float(pkg_info)
      end
      show_panel(pkg_info, pkg[1], rerender)
    end,
  })
end

outline = function(...)
  log(debug.traceback())
  local arg = select(1, ...)
  local path = vim.fn.expand("%:p:h")
  path = vfn.fnamemodify(path, ":p")

  if arg == "-p" then
    path = select(2, ...)
  else
    path = "." .. util.sep() .. "..." -- how about window?
  end
  local re_render = false
  if arg == "-r" then
    re_render = true
  end
  local pkg = path_to_pkg[path]
  if not pkg then
    pkg = pkg_from_path(path) -- return list of all packages only check first one
    path_to_pkg[path] = pkg
  end
  if vfn.empty(pkg) == 1 then
    util.log("No package found in current directory.")
    return nil
  end
  local setup = { "go", "doc", "-all", "-u", "-cmd", pkg[1] }
  gen_pkg_info(setup, pkg, arg, re_render)
end

render = function(bufnr)
  log(debug.traceback())
  local fpath = vfn.fnamemodify(vfn.bufname(bufnr or 0), ":p")
  local pkg = path_to_pkg[fpath]
  if not pkg then
    pkg = pkg_from_path("." .. util.sep() .. "...", bufnr) -- return list of all packages only check first one
    path_to_pkg[fpath] = pkg
  end
  if vfn.empty(pkg) == 1 then
    util.log("No package found in current directory.")
    return nil
  end
  local cmd = { "go", "doc", "-all", "-u", "-cmd", pkg[1] }
  log("gen_pkg_info", cmd, pkg)
  vfn.jobstart(cmd, {
    on_stdout = handle_data_out,
    on_exit = function(e, data, _)
      if data ~= 0 then
        log("no packege info data " .. e .. tostring(data))
        return
      end
      bufnr, fname = render_outline(result)
      log(bufnr, fname)
    end,
  })
  return defs
end

return {
  complete = complete,
  all_pkgs = all_pkgs,
  pkg_from_path = pkg_from_path,
  outline = outline,
}

--[[
result of workspacesymbol
{ {
    containerName = "github.com/vendor/packagename/internal/aws",
    kind = 12,
    location = {
      range = {
        end = {
          character = 23,
          line = 39
        },
        start = {
          character = 5,
          line = 39
        }
      },
      uri = "file:///go_home/src/vendor/packagename/internal/aws/aws.go"
    },
    name = "S3EndpointResolver"
  } }
]]