--!A cross-platform build utility based on Lua
--
-- Licensed under the Apache License, Version 2.0 (the "License");
-- you may not use this file except in compliance with the License.
-- You may obtain a copy of the License at
--
--     http://www.apache.org/licenses/LICENSE-2.0
--
-- Unless required by applicable law or agreed to in writing, software
-- distributed under the License is distributed on an "AS IS" BASIS,
-- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-- See the License for the specific language governing permissions and
-- limitations under the License.
--
-- Copyright (C) 2015-present, Xmake Open Source Community.
--
-- @author      ruki
-- @file        config.lua
--

-- define module
local config = config or {}

-- load modules
local io            = require("base/io")
local os            = require("base/os")
local path          = require("base/path")
local table         = require("base/table")
local utils         = require("base/utils")
local option        = require("base/option")
local is_cross      = require("base/private/is_cross")

-- always use workingdir?
--
-- If the -P/-F parameter is specified, we use workingdir as the configuration root
--
-- But we cannot call `option.get("project")`, because the menu script
-- will also fetch the configdir, but at this point,
-- the option has not yet finished parsing.
function config._use_workingdir()
    local use_workingdir = config._USE_WORKINGDIR
    if use_workingdir == nil then
        for _, arg in ipairs(xmake._ARGV) do
            if arg == "-P" or arg == "-F" or
                arg:startswith("--project=") or arg:startswith("--file=") then
                use_workingdir = true
            end
        end
        use_workingdir = use_workingdir or false
        config._USE_WORKINGDIR = use_workingdir
    end
    return use_workingdir
end

-- the current config is belong to the given config values?
function config._is_value(value, ...)
    if value == nil then
        return false
    end

    value = tostring(value)
    for _, v in ipairs(table.pack(...)) do
        -- escape '-'
        v = tostring(v)
        if value == v or value:find("^" .. v:gsub("%-", "%%-") .. "$") then
            return true
        end
    end
    return false
end

-- get the current given configuration
function config.get(name)
    local value = nil
    if config._CONFIGS then
        value = config._CONFIGS[name]
        if type(value) == "string" and value == "auto" then
            value = nil
        end
    end
    return value
end

-- this config name is readonly?
function config.readonly(name)
    return config._MODES and config._MODES["__readonly_" .. name]
end

-- set the given configure to the current
--
-- @param name  the name
-- @param value the value
-- @param opt   the argument options, e.g. {readonly = false, force = false}
--
function config.set(name, value, opt)
    opt = opt or {}
    assert(name)
    assert(opt.force or not config.readonly(name), "cannot set readonly config: " .. name)

    config._CONFIGS = config._CONFIGS or {}
    config._CONFIGS[name] = value
    if opt.readonly then
        config._MODES = config._MODES or {}
        config._MODES["__readonly_" .. name] = true
    end
end

-- get the current platform
function config.plat()
    return config.get("plat")
end

-- get the current architecture
function config.arch()
    return config.get("arch")
end

-- get the current mode
function config.mode()
    return config.get("mode")
end

-- get the current host
function config.host()
    return config.get("host")
end

-- get all options
function config.options()

    -- remove values with "auto" and private item
    local configs = {}
    if config._CONFIGS then
        for name, value in pairs(config._CONFIGS) do
            if not name:find("^_%u+") and (type(value) ~= "string" or value ~= "auto") then
                configs[name] = value
            end
        end
    end
    return configs
end

-- get the builddir
-- we can use `{absolute = true}` to force to get absolute path
function config.builddir(opt)

    -- get the absolute path first
    opt = opt or {}
    local rootdir
    -- we always switch to independent working directory if `-P/-F` is set
    -- @see https://github.com/xmake-io/xmake/issues/3342
    if not rootdir and config._use_workingdir() then
        rootdir = os.workingdir()
    end
    -- we switch to independent working directory if .xmake exists
    -- @see https://github.com/xmake-io/xmake/issues/820
    if not rootdir and os.isdir(path.join(os.workingdir(), "." .. xmake._NAME)) then
        rootdir = os.workingdir()
    end
    if not rootdir then
        rootdir = os.projectdir()
    end
    local builddir = config.get("builddir") or config.get("buildir") or "build"
    if not path.is_absolute(builddir) then
        builddir = path.absolute(builddir, rootdir)
    end

    -- adjust path for the current directory
    if not opt.absolute then
        builddir = path.relative(builddir, os.curdir())
    end
    return builddir
end

-- get build directory (deprecated)
function config.buildir(opt)
    utils.warning("config.buildir() has been deprecated, please use config.builddir()")
    return config.builddir(opt)
end

-- get the configure file
function config.filepath()
    return path.join(config.directory(), xmake._NAME .. ".conf")
end

-- get the local cache directory
function config.cachedir()
    return path.join(config.directory(), "cache")
end

-- get the configure directory on the current host/arch platform
function config.directory()
    if config._DIRECTORY == nil then
        local rootdir = os.getenv("XMAKE_CONFIGDIR")
        -- we always switch to independent working directory if `-P/-F` is set
        -- @see https://github.com/xmake-io/xmake/issues/3342
        if not rootdir and config._use_workingdir() then
            rootdir = os.workingdir()
        end
        -- we switch to independent working directory if .xmake exists
        -- @see https://github.com/xmake-io/xmake/issues/820
        if not rootdir and os.isdir(path.join(os.workingdir(), "." .. xmake._NAME)) then
            rootdir = os.workingdir()
        end
        if not rootdir then
            rootdir = os.projectdir()
        end
        config._DIRECTORY = path.join(rootdir, "." .. xmake._NAME, os.host(), os.arch())
    end
    return config._DIRECTORY
end

-- load the project configuration
--
-- @param opt   {readonly = true, force = true}
--
function config.load(filepath, opt)
    opt = opt or {}
    local configs, errors
    filepath = filepath or config.filepath()
    if os.isfile(filepath) then
        configs, errors = io.load(filepath)
        if not configs then
            utils.error(errors)
            return false
        end
    end
    -- merge into the current configuration
    local ok = false
    if configs then
        for name, value in pairs(configs) do
            if config.get(name) == nil or opt.force then
                config.set(name, value, opt)
                ok = true
            end
        end
    end
    return ok
end

-- save the project configuration
--
-- @note we pass only_changed to avoid frequent changes to the file's mtime,
-- because some plugins(vscode, compile_commands.autoupdate) depend on it's mtime.
--
function config.save(filepath, opt)
    opt = opt or {}
    filepath = filepath or config.filepath()
    if opt.public then
        local configs = {}
        for name, value in pairs(config.options()) do
            if not name:startswith("__") then
                configs[name] = value
            end
        end
        return io.save(filepath, configs, {orderkeys = true, only_changed = true})
    else
        return io.save(filepath, config.options(), {orderkeys = true, only_changed = true})
    end
end

-- read value from the configuration file directly
function config.read(name)
    local configs
    if os.isfile(config.filepath()) then
        configs = io.load(config.filepath())
    end
    local value = nil
    if configs then
        value = configs[name]
        if type(value) == "string" and value == "auto" then
            value = nil
        end
    end
    return value
end

-- clear config
function config.clear()
    config._MODES = nil
    config._CONFIGS = nil
end

-- the current mode is belong to the given modes?
function config.is_mode(...)
    return config._is_value(config.get("mode"), ...)
end

-- the current platform is belong to the given platforms?
function config.is_plat(...)
    return config._is_value(config.get("plat"), ...)
end

-- the current architecture is belong to the given architectures?
function config.is_arch(...)
    return config._is_value(config.get("arch"), ...)
end

-- is cross-compilation?
function config.is_cross()
    return is_cross(config.plat(), config.arch())
end

-- dump the configure
function config.dump()
    if not option.get("quiet") then
        utils.print("configure")
        utils.print("{")
        for name, value in pairs(config.options()) do
            if not name:startswith("__") then
                utils.print("    %s = %s", name, value)
            end
        end
        utils.print("}")
    end
end

-- return module
return config
