package config_test

import (
	"kdelsd/config"
	"reflect"
	"strings"
	"strconv"
	"testing"
)


type TestConfig struct {
	INT int
	BOOL bool
	STR string
	OTHER_STR string `optional`
	COMPLEX complex64 `optional`
}

var testConfigReference = TestConfig{
	INT: 42,
	BOOL: true,
	STR: "sajtok",
	OTHER_STR: "default-value",
}

var testEnv = []string{
	"TEST_INT=42",
	"TEST_BOOL=true",
	"TEST_STR=sajtok",
}

func configBuilder() *config.ConfigBuilder {
	cb := config.NewBuilder()
	cb.ConfigFetchMethod = func()[]string {
		return testEnv
	}

	return cb
}


func TestConfigBuilder(t *testing.T) {
	c := TestConfig{}
	c.OTHER_STR = testConfigReference.OTHER_STR
	builder := configBuilder()

	err := builder.Build("TEST_", &c)
	if err != nil {
		t.Fatalf("Config building should not fail\n")
	}

	if c != testConfigReference {
		t.Fatalf("Parsed config shoudl equal reference config\n%v != %v\n", c, testConfigReference)
	}
}

func TestConfigBuilderParsers(t *testing.T) {
	c := TestConfig{}
	builder := configBuilder()
	builder.ConfigFetchMethod = func()[]string {
		return append(testEnv, "TEST_COMPLEX=42+42i")
	}

	err := builder.Build("TEST_", &c)
	if err == nil {
		t.Fatalf("CONFIG should not be parseable, since type has no default parser\n")
	}
	if !strings.Contains(err.Error(), "complex64") {
		t.Fatalf("Error should contain the type that failed to parse\n")
	}

	builder.RegisterParser(reflect.Complex64, func(value string)(interface{}, error) {
		num, err := strconv.ParseComplex(value, 64)
		if err != nil {
			return nil, err
		}
		return num, nil
	})
	err = builder.Build("TEST_", &c)
	if err != nil {
		t.Fatalf("Parsing type should not fail after registering a parser for it\n")
	}
}

func TestConfigBuilderOptional(t *testing.T) {
	type RequiredConfig struct {
		REQUIRED_STR string
	}
	c := RequiredConfig{}
	builder := config.NewBuilder()

	err := builder.Build("TEST_", &c)
	if err == nil {
		t.Fatalf("Fields not marked with the `optional` tag should be mandatory\n")
	}
	if !strings.Contains(err.Error(), "REQUIRED_STR") {
		t.Fatalf("Error should contain the name of the field\n")
	}

	builder.ConfigFetchMethod = func()[]string {
		return append(testEnv, "TEST_REQUIRED_STR=prrrr")
	}
	err = builder.Build("TEST_", &c)
	if err != nil {
		t.Fatalf("Config building should not fail after providing the mandatory field\n")
	}
}