package generate

// import "fmt"
import "strings"
import "testing"
import "git.tebibyte.media/sashakoshka/goparse"

var testGenerateCorrect =
`package protocol

/* # Do not edit this package by hand!
 * 
 * This file was automatically generated by the Holanet PDL compiler. The
 * source file is located at input.pdl
 * Please edit that file instead, and re-compile it to this location.
 *
 * HOPP, TAPE, METADAPT, PDL/0 (c) 2025 holanet.xyz
 */

import "git.tebibyte.media/sashakoshka/hopp/tape"

// Table is a KTV table with an undefined schema.
type Table map[uint16] any

// Message is any message that can be sent along this protocol.
type Message interface {
	tape.Encodable
	tape.Decodable

	// Method returns the method code of the message.
	Method() uint16
}

// User represents the protocol data type User.
type User struct {
	Name string
	Bio string
	Followers uint32
}

// EncodeValue encodes the value of this type without the tag. The value is
// encoded according to the parameters specified by the tag, if possible.
func (this *User) EncodeValue(encoder *tape.Encoder) (n int, err error) {
	nn, err := tape.WriteTableHeader(2)
	n += nn; if err != nil { return n, err }
	nn, err := encoder.WriteUint16(0x0000)
	n += nn; if err != nil { return n, err }
	nn, err := tape.WriteString(encoder, this.Name)
	n += nn; if err != nil { return n, err }
	nn, err := encoder.WriteUint16(0x0001)
	n += nn; if err != nil { return n, err }
	nn, err := tape.WriteString(encoder, this.Bio)
	n += nn; if err != nil { return n, err }
	return n, nil
}

// Decode replaces the data in this User with information from the decoder.
func (this *User) Decode(decoder *tape.Decoder) (n int, err error) {
	pull, nn, err := tape.ReadTableHeader(decoder)
	n += nn; if err != nil { return n, err }

	for {
		key, tag, end, nn, err := pull()
		n += nn; if err != nil { return n, err }
		if end { break }

		switch key {
		case 0x0000:
			value, nn, err := tape.ReadString(decoder)
			n += nn; if err != nil { return n, err }
			this.Name = value
		case 0x0001:
			value, nn, err := tape.ReadString(decoder)
			n += nn; if err != nil { return n, err }
			this.Bio = value 
		}
	}
	
	return n, nil
}

// MessageConnect represents the protocol message M0000 Connect.
type MessageConnect struct {
	Name string
	Password string
}

// Method returns the method code, M0000.
func (this *MessageConnect) Method() uint16 {
	return 0x0000
}

// Encode encodes the message to the encoder.
func (this *MessageConnect) Encode(encoder *tape.Encoder) (n int, err error) {
	nn, err := tape.WriteTableHeader(2)
	n += nn; if err != nil { return n, err }
	nn, err := encoder.WriteUint16(0x0000)
	n += nn; if err != nil { return n, err }
	nn, err := tape.WriteString(encoder, this.Name)
	n += nn; if err != nil { return n, err }
	nn, err := encoder.WriteUint16(0x0001)
	n += nn; if err != nil { return n, err }
	nn, err := tape.WriteString(encoder, this.Password)
	n += nn; if err != nil { return n, err }
	return n, nil
}

// Decode replaces the data in this message with information from the decoder.
func (this *MessageConnect) Decode(decoder *tape.Decoder) (n int, err error) {
	pull, nn, err := tape.ReadTableHeader(decoder)
	n += nn; if err != nil { return n, err }

	for {
		key, tag, end, nn, err := pull()
		n += nn; if err != nil { return n, err }
		if end { break }

		switch key {
		case 0x0000:
			value, nn, err := tape.ReadString(decoder)
			n += nn; if err != nil { return n, err }
			this.Name = value
		case 0x0001:
			value, nn, err := tape.ReadString(decoder)
			n += nn; if err != nil { return n, err }
			this.Password = value 
		}
	}
	
	return n, nil
}

// MessageUserList represents the protocol message M0001 UserList.
type MessageUserList struct {
	Users []User
}

// Method returns the method code, M0001.
func (this *MessageUserList) Method() uint16 {
	return 0x0001
}

// TODO methods
`

func TestGenerate(test *testing.T) {
	protocol := defaultProtocol()
	protocol.Messages[0x0000] = Message {
		Name: "Connect",
		Type: TypeTableDefined {
			Fields: map[uint16] Field {
				0x0000: Field { Name: "Name",      Type: TypeString { } },
				0x0001: Field { Name: "Password",  Type: TypeString { } },
			},
		},
	}
	protocol.Messages[0x0001] = Message {
		Name: "UserList",
		Type: TypeTableDefined {
			Fields: map[uint16] Field {
				0x0000: Field { Name: "Users",  Type: TypeArray { Element: TypeNamed { Name: "User" } } },
			},
		},
	}
	protocol.Types["User"] = TypeTableDefined {
		Fields: map[uint16] Field {
			0x0000: Field { Name: "Name",      Type: TypeString { } },
			0x0001: Field { Name: "Bio",       Type: TypeString { } },
			0x0002: Field { Name: "Followers", Type: TypeInt { Bits: 32 } },
		},
	}

	correct := testGenerateCorrect

	builder := strings.Builder { }
	generator := Generator { Output: &builder }
	/* TODO test n: */ _, err := generator.Generate(&protocol)
	if err != nil { test.Fatal(parse.Format(err)) }
	got := builder.String()

	test.Log("CORRECT:")
	test.Log(correct)
	test.Log("GOT:")
	test.Log(got)

	if correct != got {
		test.Error("not equal")
		for index := range min(len(correct), len(got)) {
			if correct[index] == got[index] { continue }
			test.Log("C:", correct[max(0, index - 8):min(len(correct), index + 8)])
			test.Log("G:", got[max(0, index - 8):min(len(got), index + 8)])
			break
		}
		test.FailNow()
	}
}

func TestGenerateRun(test *testing.T) {
	protocol := defaultProtocol()
	protocol.Messages[0x0000] = Message {
		Name: "Connect",
		Type: TypeTableDefined {
			Fields: map[uint16] Field {
				0x0000: Field { Name: "Name",      Type: TypeString { } },
				0x0001: Field { Name: "Password",  Type: TypeString { } },
			},
		},
	}
	protocol.Messages[0x0001] = Message {
		Name: "UserList",
		Type: TypeTableDefined {
			Fields: map[uint16] Field {
				0x0000: Field { Name: "Users",  Type: TypeArray { Element: TypeNamed { Name: "User" } } },
			},
		},
	}
	protocol.Types["User"] = TypeTableDefined {
		Fields: map[uint16] Field {
			0x0000: Field { Name: "Name",      Type: TypeString { } },
			0x0001: Field { Name: "Bio",       Type: TypeString { } },
			0x0002: Field { Name: "Followers", Type: TypeInt { Bits: 32 } },
		},
	}
	testGenerateRun(test, &protocol, `
		// imports
	`, `
		// test case
		messageConnect := MessageConnect {
			Name: "rarity",
			Password: "gems",
		}
		testEncode(
			&messageConnect,
			0x0) // TODO
	`)
}