"""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):
    gdnative_api_init_macro = [
        '\textern const godot_gdnative_core_api_struct *_gdnative_wrapper_api_struct;'
    ]

    for ext in api['extensions']:
        name = ext['name']
        gdnative_api_init_macro.append(
            '\textern const godot_gdnative_ext_{0}_api_struct *_gdnative_wrapper_{0}_api_struct;'.format(name))

    gdnative_api_init_macro.append('\t_gdnative_wrapper_api_struct = options->api_struct;')
    gdnative_api_init_macro.append('\tfor (unsigned int i = 0; i < _gdnative_wrapper_api_struct->num_extensions; i++) { ')
    gdnative_api_init_macro.append('\t\tswitch (_gdnative_wrapper_api_struct->extensions[i]->type) {')

    for ext in api['extensions']:
        name = ext['name']
        gdnative_api_init_macro.append(
            '\t\t\tcase GDNATIVE_EXT_%s:' % ext['type'])
        gdnative_api_init_macro.append(
            '\t\t\t\t_gdnative_wrapper_{0}_api_struct = (godot_gdnative_ext_{0}_api_struct *)'
            ' _gdnative_wrapper_api_struct->extensions[i];'.format(name))
        gdnative_api_init_macro.append('\t\t\t\tbreak;')
    gdnative_api_init_macro.append('\t\t}')
    gdnative_api_init_macro.append('\t}')

    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 <pluginscript/godot_pluginscript.h>',
        '',
        '#define GDNATIVE_API_INIT(options) do {  \\\n' + '  \\\n'.join(gdnative_api_init_macro) + '  \\\n } while (0)',
        '',
        '#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

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

    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

    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']

    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']) + '},',
        '\tNULL,',
        '\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))


def _build_gdnative_wrapper_code(api):
    out = [
        '/* THIS FILE IS GENERATED DO NOT EDIT */',
        '',
        '#include <gdnative/gdnative.h>',
        '#include <nativescript/godot_nativescript.h>',
        '#include <pluginscript/godot_pluginscript.h>',
        '#include <arvr/godot_arvr.h>',
        '',
        '#include <gdnative_api_struct.gen.h>',
        '',
        '#ifdef __cplusplus',
        'extern "C" {',
        '#endif',
        '',
        'godot_gdnative_core_api_struct *_gdnative_wrapper_api_struct = 0;',
    ]

    for ext in api['extensions']:
        name = ext['name']
        out.append('godot_gdnative_ext_' + name + '_api_struct *_gdnative_wrapper_' + name + '_api_struct = 0;')

    out += ['']

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

        args = ', '.join(['%s' % n for t, n in funcdef['arguments']])

        return_line = '\treturn ' if funcdef['return_type'] != 'void' else '\t'
        return_line += '_gdnative_wrapper_api_struct->' + funcdef['name'] + '(' + args + ');'

        out.append(return_line)
        out.append('}')
        out.append('')

    for ext in api['extensions']:
        name = ext['name']
        for funcdef in ext['api']:
            args = ', '.join(['%s%s' % (_spaced(t), n) for t, n in funcdef['arguments']])
            out.append('%s%s(%s) {' % (_spaced(funcdef['return_type']), funcdef['name'], args))

            args = ', '.join(['%s' % n for t, n in funcdef['arguments']])

            return_line = '\treturn ' if funcdef['return_type'] != 'void' else '\t'
            return_line += '_gdnative_wrapper_' + name + '_api_struct->' + funcdef['name'] + '(' + args + ');'

            out.append(return_line)
            out.append('}')
            out.append('')

    out += [
        '#ifdef __cplusplus',
        '}',
        '#endif'
    ]

    return '\n'.join(out)


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

    wrapper_file = target[0]
    with open(wrapper_file, 'w') as fd:
        fd.write(_build_gdnative_wrapper_code(api))


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