--!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        proto.lua
--

-- imports
import("core.base.option")
import("lib.detect.find_tool")
import("core.project.depend")
import("utils.progress")
import("private.utils.batchcmds")

-- get protoc
function _get_protoc(target, sourcekind)

    -- find protoc
    -- @see https://github.com/xmake-io/xmake/issues/4659
    local envs = os.joinenvs(target:pkgenvs(), os.getenvs())
    local protoc = target:data("protobuf.protoc")
    if not protoc and sourcekind == "cxx" then
        protoc = find_tool("protoc", {envs = envs})
        if protoc and protoc.program then
            target:data_set("protobuf.protoc", protoc.program)
        end
    end

    -- find protoc-c
    local protoc_c = target:data("protobuf.protoc-c")
    if not protoc_c and sourcekind == "cc" then
        protoc_c = find_tool("protoc-c", {envs = envs}) or protoc
        if protoc_c and protoc_c.program then
            target:data_set("protobuf.protoc-c", protoc_c.program)
        end
    end

    -- get protoc
    return assert(target:data(sourcekind == "cxx" and "protobuf.protoc" or "protobuf.protoc-c"), "protoc not found!")
end

-- get grpc_cpp_plugin
function _get_grpc_cpp_plugin(target, sourcekind)
    local envs = os.joinenvs(target:pkgenvs(), os.getenvs())
    assert(sourcekind == "cxx", "grpc_cpp_plugin only support c++")
    local grpc_cpp_plugin = find_tool("grpc_cpp_plugin", {norun = true, force = true, envs = envs})
    return assert(grpc_cpp_plugin and grpc_cpp_plugin.program, "grpc_cpp_plugin not found!")
end

-- we need to add some configs to export includedirs to other targets in on_load
-- @see https://github.com/xmake-io/xmake/issues/2256
function load(target, sourcekind)

    local sourcebatch = target:sourcebatches()[sourcekind == "cxx" and "protobuf.cpp" or "protobuf.c"]
    for _, sourcefile_proto in ipairs(sourcebatch and sourcebatch.sourcefiles) do
        local prefixdir
        local autogendir
        local public
        local grpc_cpp_plugin
        local fileconfig = target:fileconfig(sourcefile_proto)
        if fileconfig then
            public = fileconfig.proto_public
            prefixdir = fileconfig.proto_rootdir
            autogendir = fileconfig.proto_autogendir
            grpc_cpp_plugin = fileconfig.proto_grpc_cpp_plugin
        end
        local rootdir = autogendir and autogendir or path.join(target:autogendir(), "rules", "protobuf")
        local filename = path.basename(sourcefile_proto) .. ".pb" .. (sourcekind == "cxx" and ".cc" or "-c.c")
        local sourcefile_cx = target:autogenfile(sourcefile_proto, {rootdir = rootdir, filename = filename})
        local sourcefile_dir = prefixdir and path.join(rootdir, prefixdir) or path.directory(sourcefile_cx)

        -- add includedirs
        target:add("includedirs", sourcefile_dir, {public = public})

        -- add objectfile, @see https://github.com/xmake-io/xmake/issues/5426
        local objectfile_grpc
        local objectfile = target:objectfile(sourcefile_cx)
        table.insert(target:objectfiles(), objectfile)
        if grpc_cpp_plugin then
            local filename_grpc = path.basename(sourcefile_proto) .. ".grpc.pb.cc"
            local sourcefile_cx_grpc = target:autogenfile(sourcefile_proto, {rootdir = rootdir, filename = filename_grpc})
            objectfile_grpc = target:objectfile(sourcefile_cx_grpc)
            table.insert(target:objectfiles(), objectfile_grpc)
        end
    end
end

function buildcmd_pfile(target, batchcmds, sourcefile_proto, sourcekind, opt)

    -- get protoc
    local protoc = _get_protoc(target, sourcekind)

    -- get c/c++ source file for protobuf
    local prefixdir
    local autogendir
    local public
    local grpc_cpp_plugin
    local proto_flags
    local fileconfig = target:fileconfig(sourcefile_proto)
    if fileconfig then
        public = fileconfig.proto_public
        prefixdir = fileconfig.proto_rootdir
        -- custom autogen directory to access the generated header files
        -- @see https://github.com/xmake-io/xmake/issues/3678
        autogendir = fileconfig.proto_autogendir
        grpc_cpp_plugin = fileconfig.proto_grpc_cpp_plugin
        -- custom flags, pass through to protoc
        proto_flags = fileconfig.proto_flags
    end
    local rootdir = autogendir and autogendir or path.join(target:autogendir(), "rules", "protobuf")
    local filename = path.basename(sourcefile_proto) .. ".pb" .. (sourcekind == "cxx" and ".cc" or "-c.c")
    local sourcefile_cx = target:autogenfile(sourcefile_proto, {rootdir = rootdir, filename = filename})
    local sourcefile_dir = prefixdir and path.join(rootdir, prefixdir) or path.directory(sourcefile_cx)

    local grpc_cpp_plugin_bin
    local filename_grpc
    local sourcefile_cx_grpc
    if grpc_cpp_plugin then
        grpc_cpp_plugin_bin = _get_grpc_cpp_plugin(target, sourcekind)
        filename_grpc = path.basename(sourcefile_proto) .. ".grpc.pb.cc"
        sourcefile_cx_grpc = target:autogenfile(sourcefile_proto, {rootdir = rootdir, filename = filename_grpc})
    end

    local protoc_args = {
        path(sourcefile_proto),
        path(prefixdir and prefixdir or path.directory(sourcefile_proto), function (p) return "-I" .. p end),
        path(sourcefile_dir, function (p) return (sourcekind == "cxx" and "--cpp_out=" or "--c_out=") .. p end)
    }

    if grpc_cpp_plugin then
        local extension = target:is_plat("windows") and ".exe" or ""
        table.insert(protoc_args, "--plugin=protoc-gen-grpc=" .. grpc_cpp_plugin_bin .. extension)
        table.insert(protoc_args, path(sourcefile_dir, function (p) return ("--grpc_out=") .. p end))
    end

    if proto_flags then
        table.join2(protoc_args, proto_flags)
    end

    -- add commands
    batchcmds:mkdir(sourcefile_dir)
    batchcmds:show_progress(
        opt.progress,
        "${color.build.object}compiling.proto.%s %s",
        (sourcekind == "cxx" and "c++" or "c"),
        sourcefile_proto
    )
    batchcmds:vrunv(protoc, protoc_args)

    -- add deps
    local depmtime = os.mtime(sourcefile_cx)
    batchcmds:add_depfiles(sourcefile_proto)
    batchcmds:set_depcache(target:dependfile(sourcefile_cx))
    if grpc_cpp_plugin then
        batchcmds:set_depmtime(math.max(os.mtime(sourcefile_cx_grpc), depmtime))
    else
        batchcmds:set_depmtime(depmtime)
    end
end

function buildcmd_cxfile(target, batchcmds, sourcefile_proto, sourcekind, opt)

    -- get protoc
    local protoc = _get_protoc(target, sourcekind)

    -- get c/c++ source file for protobuf
    local prefixdir
    local autogendir
    local public
    local grpc_cpp_plugin
    local fileconfig = target:fileconfig(sourcefile_proto)
    if fileconfig then
        public = fileconfig.proto_public
        prefixdir = fileconfig.proto_rootdir
        -- custom autogen directory to access the generated header files
        -- @see https://github.com/xmake-io/xmake/issues/3678
        autogendir = fileconfig.proto_autogendir
        grpc_cpp_plugin = fileconfig.proto_grpc_cpp_plugin
    end
    local rootdir = autogendir and autogendir or path.join(target:autogendir(), "rules", "protobuf")
    local filename = path.basename(sourcefile_proto) .. ".pb" .. (sourcekind == "cxx" and ".cc" or "-c.c")
    local sourcefile_cx = target:autogenfile(sourcefile_proto, {rootdir = rootdir, filename = filename})
    local sourcefile_dir = prefixdir and path.join(rootdir, prefixdir) or path.directory(sourcefile_cx)

    local grpc_cpp_plugin_bin
    local filename_grpc
    local sourcefile_cx_grpc
    if grpc_cpp_plugin then
        grpc_cpp_plugin_bin = _get_grpc_cpp_plugin(target, sourcekind)
        filename_grpc = path.basename(sourcefile_proto) .. ".grpc.pb.cc"
        sourcefile_cx_grpc = target:autogenfile(sourcefile_proto, {rootdir = rootdir, filename = filename_grpc})
    end

    -- get objectfile
    local objectfile = target:objectfile(sourcefile_cx)
    local objectfile_grpc
    if grpc_cpp_plugin then
        objectfile_grpc = target:objectfile(sourcefile_cx_grpc)
    end

    batchcmds:show_progress(opt.progress, "${color.build.object}compiling.proto.$(mode) %s", sourcefile_cx)
    batchcmds:compile(sourcefile_cx, objectfile, {configs = {includedirs = sourcefile_dir}})
    if grpc_cpp_plugin then
        batchcmds:compile(sourcefile_cx_grpc, objectfile_grpc, {configs = {includedirs = sourcefile_dir}})
    end

    -- add deps
    local depmtime = os.mtime(objectfile)
    batchcmds:add_depfiles(sourcefile_proto)
    batchcmds:set_depcache(target:dependfile(objectfile))
    if grpc_cpp_plugin then
        batchcmds:set_depmtime(math.max(os.mtime(objectfile_grpc), depmtime))
    else
        batchcmds:set_depmtime(depmtime)
    end
end