// Copyright 2018 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// This file implements outputLanguage for Dart
package source_generator

import (
	"sort"
)

type Dart struct{}

func (_ Dart) getCommentPrefix() string { return "//" }
func (_ Dart) supportsTypeAlias() bool  { return false }

func (_ Dart) writeExtraHeader(so *sourceOutputter, projectName, customerName string, namespaces []string) {
}
func (_ Dart) writeExtraFooter(so *sourceOutputter, projectName, customerName string, namespaces []string) {
}

func (_ Dart) writeEnumBegin(so *sourceOutputter, name ...string) {
	so.writeLineFmt("class %s {", toPascalCase(name...))
}

func (_ Dart) writeEnumEntry(so *sourceOutputter, value uint32, name ...string) {
	so.writeLineFmt("  static const int %s = %d;", toPascalCase(name...), value)
}

func (_ Dart) writeEnumAliasesBegin(so *sourceOutputter, name ...string) {
}

func (_ Dart) writeEnumAlias(so *sourceOutputter, name, from, to []string) {
	so.writeLineFmt("  static const int %s = %s;", toPascalCase(to...), toPascalCase(from...))
}

func (_ Dart) writeEnumEnd(so *sourceOutputter, name ...string) {
	so.writeLineFmt("}")
}

func (_ Dart) writeEnumExport(so *sourceOutputter, enumName, name []string) {
	enum := toPascalCase(enumName...)
	variant := toPascalCase(name...)
	so.writeLineFmt("const int %s_%s = %s.%s;", enum, variant, enum, variant)
}

func (_ Dart) writeTypeAlias(so *sourceOutputter, from, to []string)                                {}
func (_ Dart) writeNamespacesBegin(so *sourceOutputter, namespaces []string, outputFilename string) {}
func (_ Dart) writeNamespacesEnd(so *sourceOutputter, namespaces []string, outputFilename string)   {}

func (_ Dart) writeConstUint32(so *sourceOutputter, value uint32, name ...string) {
	so.writeComment("ignore: constant_identifier_names")
	so.writeLineFmt("const int %s = %d;", toCamelCase(name...), value)
}

func (_ Dart) writeConstInt64(so *sourceOutputter, value int64, name ...string) {
	so.writeComment("ignore: constant_identifier_names")
	so.writeLineFmt("const int %s = %d;", toCamelCase(name...), value)
}
func (_ Dart) writeConstMap(so *sourceOutputter, value map[uint32]string, name ...string) {
	var keys []uint32
	for k := range value {
		keys = append(keys, k)
	}
	sort.Slice(keys, func(i, j int) bool { return keys[i] < keys[j] })

	so.writeComment("ignore: constant_identifier_names")
	so.writeLineFmt("const Map<String, int> %s = {", toCamelCase(name...))
	for _, id := range keys {
		dimensionValue := value[id]
		so.writeLineFmt("    '%s': %d,", dimensionValue, id)
	}
	so.writeLineFmt("};")
}

func (_ Dart) writeStringConstant(so *sourceOutputter, value string, name ...string) {
	so.writeLineFmt("const String %s = '%s';", toCamelCase(name...), value)
}

func (_ Dart) writeStructBegin(so *sourceOutputter, name ...string) {
	so.writeLineFmt("class %s {", toPascalCase(name...))
}

func (_ Dart) writeStructField(so *sourceOutputter, name, typeName []string) {
	so.writeLineFmt("  int %s = 0;", toSnakeCase(name...))
}

func (_ Dart) writeToVectorMethod(so *sourceOutputter, structName []string, fields [][]string) {
	so.writeLine("")
	so.writeLine("  List<int> toList() {")
	so.writeLineFmt("    return [")
	for _, field := range fields {
		so.writeLineFmt("      %s,", toSnakeCase(field...))
	}
	so.writeLineFmt("    ];")
	so.writeLine("  }")
}

func (_ Dart) writeStructEnd(so *sourceOutputter) {
	so.writeLine("}")
}

// Returns an output formatter that will output the contents of a Dart file
// that contains a variable declaration for a string literal that contains
// the base64-encoding of the serialized proto.
//
// varName will be the name of the variable containing the base64-encoded serialized proto.
// namespace is a list of nested namespaces inside of which the variable will be defined.
// If forTesting is true, a constant will be generated for each report ID, based on the report's name.
func DartOutputFactory(varName string, options generatorOptions) OutputFormatter {
	return newSourceOutputter(Dart{}, varName, options).getOutputFormatter()
}