--!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        find_ndk.lua
--

-- imports
import("core.base.option")
import("core.base.global")
import("core.project.config")
import("core.cache.detectcache")
import("lib.detect.find_directory")

-- get triple
function _get_triple(arch)
    local triples =
    {
        ["armv5te"]     = "arm-linux-androideabi"   -- deprecated
    ,   ["armv7-a"]     = "arm-linux-androideabi"   -- deprecated
    ,   ["armeabi"]     = "arm-linux-androideabi"   -- removed in ndk r17
    ,   ["armeabi-v7a"] = "arm-linux-androideabi"
    ,   ["arm64-v8a"]   = "aarch64-linux-android"
    ,   ["riscv64"]     = "riscv64-linux-android"
    ,   i386            = "i686-linux-android"      -- deprecated
    ,   x86             = "i686-linux-android"
    ,   x86_64          = "x86_64-linux-android"
    ,   mips            = "mips-linux-android"      -- removed in ndk r17
    ,   mips64          = "mips64-linux-android"    -- removed in ndk r17
    }
    return triples[arch]
end

-- find ndk directory
function _find_ndkdir(sdkdir)

    -- get ndk directory
    if not sdkdir then
        sdkdir = os.getenv("ANDROID_NDK_HOME") or os.getenv("ANDROID_NDK_ROOT")
        if not sdkdir and config.get("android_sdk") then
            local ndkbundle = path.join(config.get("android_sdk"), "ndk-bundle")
            if os.isdir(ndkbundle) then
                sdkdir = ndkbundle
            end
        end
        if not sdkdir and is_host("macosx") then
            sdkdir = find_directory("NDK", "/Applications/AndroidNDK*.app/Contents")
            if not sdkdir then
                sdkdir = find_directory("*", "~/Library/Android/sdk/ndk")
            end
            if not sdkdir then
                sdkdir = "~/Library/Android/sdk/ndk-bundle"
            end
        end
    end

    -- get ndk directory
    if sdkdir and os.isdir(sdkdir) then
        return path.translate(sdkdir)
    end
end

-- find the sdk version of ndk
function _find_ndk_sdkver(sdkdir, bindir, sysroot, arch)

    -- uses llvm stl?
    local use_llvm = false
    local ndk_cxxstl = config.get("ndk_cxxstl")
    if ndk_cxxstl then
        -- we uses c++_static/c++_shared instead of llvmstl_static/llvmstl_shared
        if ndk_cxxstl:startswith("c++") or ndk_cxxstl:startswith("llvmstl") then
            use_llvm = true
        end
    elseif bindir and bindir:find("llvm", 1, true) then
        use_llvm = true
    end

    -- get triple
    local triple = _get_triple(arch)
    assert(triple, "no triple found for arch %s (wrong arch?)", arch)

    -- try to select the best compatible version
    local sdkver = "16"
    if use_llvm or arch == "arm64-v8a" or arch == "riscv64" then
        sdkver = (arch == "riscv64") and "35" or "21"
    end
    if sysroot then
        if os.isdir(path.join(sysroot, "usr", "lib", triple, sdkver)) then
            return sdkver
        end
    end
    if os.isdir(path.join(sdkdir, "platforms", "android-" .. sdkver)) then
        return sdkver
    end

    -- find the max version
    local sdkver_max = 0
    local sdkver_dir_pattern
    if sysroot and os.isdir(path.join(sysroot, "usr", "lib")) then
        sdkver_dir_pattern = path.join(sysroot, "usr", "lib", triple, "*")
    else
        sdkver_dir_pattern = path.join(sdkdir, "platforms", "android-*")
    end
    for _, sdkdir in ipairs(os.dirs(sdkver_dir_pattern)) do

        -- get version
        local filename = path.filename(sdkdir)
        local version, count = filename:gsub("android%-", "")
        if count > 0 then

            -- get the max version
            local sdkver_now = tonumber(version)
            if sdkver_now > sdkver_max then
                sdkver_max = sdkver_now
            end
        end
    end

    -- get the max sdk version
    return sdkver_max > 0 and tostring(sdkver_max) or nil
end

-- find the toolchains version of ndk
function _find_ndk_toolchains_ver(bindir)
    return bindir:match("%-(%d*%.%d*)[/\\]")
end

-- find sysroot directory
function _find_ndk_sysroot(sdkdir)

    -- get sysroot above ndk r22
    -- @see https://github.com/android/ndk/wiki/Changelog-r22
    local prebuilt = (is_host("macosx") and "darwin" or os.host()) .. "-x86_64"
    local sysroot_r22 = path.join(sdkdir, "toolchains", "llvm", "prebuilt", prebuilt, "sysroot")
    if os.isdir(sysroot_r22) then
        return sysroot_r22
    end

    -- get sysroot above ndk r14
    -- @see https://android.googlesource.com/platform/ndk/+/master/docs/UnifiedHeaders.md
    local sysroot_r14 = path.join(sdkdir, "sysroot")
    if os.isdir(sysroot_r14) then
        return sysroot_r14
    end
end

-- find the ndk toolchain
function _find_ndk(opt)
    opt = opt or {}
    local arch = opt.arch
    local sdkdir = opt.sdkdir
    local ndk_sdkver = opt.ndk_sdkver
    local ndk_toolchains_ver = opt.ndk_toolchains_ver
    local compiler = opt.compiler

    -- find ndk root directory
    sdkdir = _find_ndkdir(sdkdir)
    if not sdkdir then
        return
    end

    -- get cross
    local crosses =
    {
        ["armv5te"]     = "arm-linux-androideabi-" -- deprecated
    ,   ["armv7-a"]     = "arm-linux-androideabi-" -- deprecated
    ,   ["armeabi"]     = "arm-linux-androideabi-" -- removed in ndk r17
    ,   ["armeabi-v7a"] = "arm-linux-androideabi-"
    ,   ["arm64-v8a"]   = "aarch64-linux-android-"
    ,   ["riscv64"]     = "riscv64-linux-android-"
    ,   i386            = "i686-linux-android-"    -- deprecated
    ,   x86             = "i686-linux-android-"
    ,   x86_64          = "x86_64-linux-android-"
    ,   mips            = "mips-linux-android-"    -- removed in ndk r17
    ,   mips64          = "mips64-linux-android-"  -- removed in ndk r17
    }
    local cross = crosses[arch]

    -- get gcc toolchain sub-directory
    local gcc_toolchain_subdirs =
    {
        ["armv5te"]     = "arm-linux-androideabi-*"
    ,   ["armv7-a"]     = "arm-linux-androideabi-*"
    ,   ["armeabi"]     = "arm-linux-androideabi-*"
    ,   ["armeabi-v7a"] = "arm-linux-androideabi-*"
    ,   ["arm64-v8a"]   = "aarch64-linux-android-*"
    ,   ["riscv64"]     = "riscv64-linux-android-*"
    ,   i386            = "x86-*"
    ,   x86             = "x86-*"
    ,   x86_64          = "x86_64-*"
    ,   mips            = "mipsel-linux-android-*"
    ,   mips64          = "mips64el-linux-android-*"
    }
    local gcc_toolchain_subdir = gcc_toolchain_subdirs[arch] or "arm-linux-androideabi-*"

    -- find the binary directory
    local llvm_toolchain
    local prebuilt = (is_host("macosx") and "darwin" or os.host()) .. "-x86_64"
    local bindir = find_directory("bin", path.join(sdkdir, "toolchains", "llvm", "prebuilt", prebuilt)) -- larger than ndk r16
    if bindir and compiler ~= "gcc" then
        llvm_toolchain = path.directory(bindir)
    else
        bindir = find_directory("bin", path.join(sdkdir, "toolchains", gcc_toolchain_subdir, "prebuilt", "*"))
    end
    if not bindir then
        return
    end

    -- find the gcc toolchain
    local gcc_toolchain = find_directory("bin", path.join(sdkdir, "toolchains", gcc_toolchain_subdir, "prebuilt", "*"))
    if gcc_toolchain then
        gcc_toolchain = path.directory(gcc_toolchain)
    end

    -- find the toolchains version
    local toolchains_ver = ndk_toolchains_ver or _find_ndk_toolchains_ver(gcc_toolchain or bindir)

    -- find sysroot directory
    local sysroot = _find_ndk_sysroot(sdkdir)

    -- find the sdk version
    local sdkver = ndk_sdkver or _find_ndk_sdkver(sdkdir, bindir, sysroot, arch)

    -- get ndk version, e.g. r16b, ..
    local ndkver = nil
    if sysroot then
        local ndk_version_header = path.join(sysroot, "usr/include/android/ndk-version.h")
        if os.isfile(ndk_version_header) then
            local ndk_version_info = io.readfile(ndk_version_header)
            if ndk_version_info then
                ndk_version_info = ndk_version_info:match("#define __NDK_MAJOR__ (%d+)")
                if ndk_version_info then
                    ndkver = tonumber(ndk_version_info)
                end
            end
        end
    end

    return {ndkver = ndkver,
            sdkdir = sdkdir,
            bindir = bindir,
            cross = cross,
            sdkver = sdkver,
            llvm_toolchain = llvm_toolchain, -- >= ndk r22
            gcc_toolchain = gcc_toolchain,
            toolchains_ver = toolchains_ver,
            sysroot = sysroot}
end

-- find ndk toolchains
--
-- @param sdkdir    the ndk directory
-- @param opt       the argument options
--                  e.g. {arch = "[armeabi|armeabi-v7a|arm64-v8a]", verbose = true, force = false, sdkver = 19, toolchains_ver = "4.9"}
--
-- @return          the ndk toolchains. e.g. {bindir = .., cross = ..}
--
-- @code
--
-- local toolchain = find_ndk("/xxx/android-ndk-r10e")
-- local toolchain = find_ndk("/xxx/android-ndk-r10e", {arch = "arm64-v8a"})
--
-- @endcode
--
function main(sdkdir, opt)

    -- init arguments
    opt = opt or {}

    -- attempt to load cache first
    local key = "detect.sdks.find_ndk"
    local cacheinfo = detectcache:get(key) or {}
    if not opt.force and cacheinfo.ndk and cacheinfo.ndk.sdkdir and os.isdir(cacheinfo.ndk.sdkdir) then
        return cacheinfo.ndk
    end

    -- get arch
    local arch = opt.arch or config.get("arch") or "armeabi-v7a"

    -- find ndk
    local ndk = _find_ndk({sdkdir = sdkdir or config.get("ndk") or global.get("ndk"),
            arch = arch,
            ndk_sdkver = opt.sdkver or config.get("ndk_sdkver"),
            ndk_toolchains_ver = opt.toolchains_ver or config.get("ndk_toolchains_ver"),
            compiler = opt.compiler})
    if ndk and ndk.sdkdir then
        config.set("ndk", ndk.sdkdir, {force = true, readonly = true})
        config.set("ndkver", ndk.ndkver, {force = true, readonly = true})
        config.set("ndk_sdkver", ndk.sdkver, {force = true, readonly = true})
        config.set("ndk_toolchains_ver", ndk.toolchains_ver, {force = true, readonly = true})
        if opt.verbose or option.get("verbose") then
            local extra = ""
            if ndk.sdkver then
                extra = " (sdk: " .. ndk.sdkver .. ")"
            end
            cprint("checking for Android NDK ... ${color.success}%s%s", ndk.sdkdir, extra)
        end
    else
        if opt.verbose or option.get("verbose") then
            cprint("checking for Android NDK ... ${color.nothing}${text.nothing}")
        end
    end

    -- save to cache
    cacheinfo.ndk = ndk or false
    detectcache:set(key, cacheinfo)
    return ndk
end
