local logger = require("rest-nvim.logger")
local utils = require("rest-nvim.utils")

local M = {}

---Get the environment variables file filetype
---@param path string The environment file path
---@return string|nil
local function get_filetype(path)
    local ext = vim.fn.fnamemodify(path, ":e")
    return ext == "" and nil or ext
end

---@param value any
---@return string
local function value_tostring(value)
    vim.validate({
        value = {
            value,
            function(v)
                return v == vim.NIL or vim.tbl_contains({ "nil", "number", "string", "boolean" }, type(value))
            end,
            "vim.NIL|nil|bumber|string|boolean",
        },
    })
    if value == vim.NIL or value == nil then
        return ""
    end
    return tostring(value)
end

---parse dotenv file
---with setter, it pass the values to setter function
---when setter isn't provided, returns variables table
---@param path string
---@param setter? fun(key:string,value:string)
---@return boolean ok
---@return table<string,string>|nil
function M.parse(path, setter)
    local vars
    if not setter then
        vars = {}
        setter = function(key, value)
            vars[key] = value
        end
    end
    if not utils.file_exists(path) then
        logger.error("Current environment file '" .. path .. "' was not found")
        return false
    end
    local env_ext = get_filetype(path)
    local file_contents = utils.read_file(path)
    if env_ext == "json" then
        local ok, json_tbl = pcall(vim.json.decode, file_contents)
        if not ok or type(json_tbl) ~= "table" or vim.islist(json_tbl) then
            logger.error("failed parsing json data")
            return false
        end
        for key, value in pairs(json_tbl) do
            if type(key) == "string" and type(value) ~= "table" then
                setter(key, value_tostring(value))
            end
        end
    else
        -- TODO: rewrite the parser with tree-sitter-bash instead
        local lines = vim.split(file_contents, "\n", { trimempty = true })
        logger.debug(lines)
        vim.iter(lines)
            :filter(function(line)
                return not line:match("^%s*#")
            end)
            :map(function(line)
                return line:match("^export%s*(.*)") or line
            end)
            :each(function(line)
                local name, value = line:match("([^#=%s]+)%s*=%s*(.*)")
                if name then
                    setter(name, value:match('^"([^"]*)"$') or value:match("^'([^']*)'$") or value:match("([^%s#]*)"))
                end
            end)
    end
    return true, vars
end

return M