"""Functions used to generate source files during build time

All such functions are invoked in a subprocess on Windows to prevent build flakiness.

"""
import json
from platform_methods import subprocess_main


def _spaced(e):
    return e if e[-1] == '*' else e + ' '


def _build_gdnative_api_struct_header(api):
    out = [
        '/* THIS FILE IS GENERATED DO NOT EDIT */',
        '#ifndef GODOT_GDNATIVE_API_STRUCT_H',
        '#define GODOT_GDNATIVE_API_STRUCT_H',
        '',
        '#include <gdnative/gdnative.h>',
        '#include <android/godot_android.h>',
        '#include <arvr/godot_arvr.h>',
        '#include <nativescript/godot_nativescript.h>',
        '#include <net/godot_net.h>',
        '#include <pluginscript/godot_pluginscript.h>',
        '#include <videodecoder/godot_videodecoder.h>',
        '',
        '#ifdef __cplusplus',
        'extern "C" {',
        '#endif',
        '',
        'enum GDNATIVE_API_TYPES {',
        '\tGDNATIVE_' + api['core']['type'] + ','
    ]

    for ext in api['extensions']:
        out += ['\tGDNATIVE_EXT_' + ext['type'] + ',']

    out += ['};', '']

    def generate_extension_struct(name, ext, include_version=True):
        ret_val = []
        if ext['next']:
            ret_val += generate_extension_struct(name, ext['next'])

        ret_val += [
            'typedef struct godot_gdnative_ext_' + name + ('' if not include_version else ('_{0}_{1}'.format(ext['version']['major'], ext['version']['minor']))) + '_api_struct {',
            '\tunsigned int type;',
            '\tgodot_gdnative_api_version version;',
            '\tconst godot_gdnative_api_struct *next;'
        ]

        for funcdef in ext['api']:
            args = ', '.join(['%s%s' % (_spaced(t), n) for t, n in funcdef['arguments']])
            ret_val.append('\t%s(*%s)(%s);' % (_spaced(funcdef['return_type']), funcdef['name'], args))

        ret_val += ['} godot_gdnative_ext_' + name + ('' if not include_version else ('_{0}_{1}'.format(ext['version']['major'], ext['version']['minor']))) + '_api_struct;', '']

        return ret_val


    def generate_core_extension_struct(core):
        ret_val = []
        if core['next']:
            ret_val += generate_core_extension_struct(core['next'])

        ret_val += [
            'typedef struct godot_gdnative_core_' + ('{0}_{1}'.format(core['version']['major'], core['version']['minor'])) + '_api_struct {',
            '\tunsigned int type;',
            '\tgodot_gdnative_api_version version;',
            '\tconst godot_gdnative_api_struct *next;',
        ]

        for funcdef in core['api']:
            args = ', '.join(['%s%s' % (_spaced(t), n) for t, n in funcdef['arguments']])
            ret_val.append('\t%s(*%s)(%s);' % (_spaced(funcdef['return_type']), funcdef['name'], args))

        ret_val += ['} godot_gdnative_core_' + '{0}_{1}'.format(core['version']['major'], core['version']['minor']) + '_api_struct;', '']

        return ret_val


    for ext in api['extensions']:
        name = ext['name']
        out += generate_extension_struct(name, ext, False)

    if api['core']['next']:
        out += generate_core_extension_struct(api['core']['next'])

    out += [
        'typedef struct godot_gdnative_core_api_struct {',
        '\tunsigned int type;',
        '\tgodot_gdnative_api_version version;',
        '\tconst godot_gdnative_api_struct *next;',
        '\tunsigned int num_extensions;',
        '\tconst godot_gdnative_api_struct **extensions;',
    ]

    for funcdef in api['core']['api']:
        args = ', '.join(['%s%s' % (_spaced(t), n) for t, n in funcdef['arguments']])
        out.append('\t%s(*%s)(%s);' % (_spaced(funcdef['return_type']), funcdef['name'], args))

    out += [
        '} godot_gdnative_core_api_struct;',
        '',
        '#ifdef __cplusplus',
        '}',
        '#endif',
        '',
        '#endif // GODOT_GDNATIVE_API_STRUCT_H',
        ''
    ]
    return '\n'.join(out)


def _build_gdnative_api_struct_source(api):
    out = [
        '/* THIS FILE IS GENERATED DO NOT EDIT */',
        '',
        '#include <gdnative_api_struct.gen.h>',
        ''
    ]

    def get_extension_struct_name(name, ext, include_version=True):
        return 'godot_gdnative_ext_' + name + ('' if not include_version else ('_{0}_{1}'.format(ext['version']['major'], ext['version']['minor']))) + '_api_struct'

    def get_extension_struct_instance_name(name, ext, include_version=True):
        return 'api_extension_' + name + ('' if not include_version else ('_{0}_{1}'.format(ext['version']['major'], ext['version']['minor']))) + '_struct'

    def get_extension_struct_definition(name, ext, include_version=True):

        ret_val = []

        if ext['next']:
            ret_val += get_extension_struct_definition(name, ext['next'])

        ret_val += [
            'extern const ' + get_extension_struct_name(name, ext, include_version) + ' ' + get_extension_struct_instance_name(name, ext, include_version) + ' = {',
            '\tGDNATIVE_EXT_' + ext['type'] + ',',
            '\t{' + str(ext['version']['major']) + ', ' + str(ext['version']['minor']) + '},',
            '\t' + ('NULL' if not ext['next'] else ('(const godot_gdnative_api_struct *)&' + get_extension_struct_instance_name(name, ext['next']))) + ','
        ]

        for funcdef in ext['api']:
            ret_val.append('\t%s,' % funcdef['name'])

        ret_val += ['};\n']

        return ret_val


    def get_core_struct_definition(core):
        ret_val = []

        if core['next']:
            ret_val += get_core_struct_definition(core['next'])

        ret_val += [
            'extern const godot_gdnative_core_' + ('{0}_{1}_api_struct api_{0}_{1}'.format(core['version']['major'], core['version']['minor'])) + ' = {',
            '\tGDNATIVE_' + core['type'] + ',',
            '\t{' + str(core['version']['major']) + ', ' + str(core['version']['minor']) + '},',
            '\t' + ('NULL' if not core['next'] else ('(const godot_gdnative_api_struct *)& api_{0}_{1}'.format(core['next']['version']['major'], core['next']['version']['minor']))) + ','
        ]

        for funcdef in core['api']:
            ret_val.append('\t%s,' % funcdef['name'])

        ret_val += ['};\n']

        return ret_val

    for ext in api['extensions']:
        name = ext['name']
        out += get_extension_struct_definition(name, ext, False)

    out += ['', 'const godot_gdnative_api_struct *gdnative_extensions_pointers[] = {']

    for ext in api['extensions']:
        name = ext['name']
        out += ['\t(godot_gdnative_api_struct *)&api_extension_' + name + '_struct,']

    out += ['};\n']

    if api['core']['next']:
        out += get_core_struct_definition(api['core']['next'])

    out += [
        'extern const godot_gdnative_core_api_struct api_struct = {',
        '\tGDNATIVE_' + api['core']['type'] + ',',
        '\t{' + str(api['core']['version']['major']) + ', ' + str(api['core']['version']['minor']) + '},',
        '\t(const godot_gdnative_api_struct *)&api_1_1,',
        '\t' + str(len(api['extensions'])) + ',',
        '\tgdnative_extensions_pointers,',
    ]

    for funcdef in api['core']['api']:
        out.append('\t%s,' % funcdef['name'])
    out.append('};\n')

    return '\n'.join(out)


def build_gdnative_api_struct(target, source, env):

    with open(source[0], 'r') as fd:
        api = json.load(fd)

    header, source = target
    with open(header, 'w') as fd:
        fd.write(_build_gdnative_api_struct_header(api))
    with open(source, 'w') as fd:
        fd.write(_build_gdnative_api_struct_source(api))


if __name__ == '__main__':
    subprocess_main(globals())