package bfcodegen

import (
	"git.blackforestbytes.com/BlackForestBytes/goext/langext"
	"git.blackforestbytes.com/BlackForestBytes/goext/tst"
	"os"
	"path/filepath"
	"strings"
	"testing"
)

func writeTestFile(t *testing.T, dir string, name string, content string) string {
	t.Helper()
	p := filepath.Join(dir, name)
	err := os.WriteFile(p, []byte(content), 0o644)
	tst.AssertNoErr(t, err)
	return p
}

func TestProcessIDFileSimple(t *testing.T) {
	dir := t.TempDir()

	src := `package mymodels

type UserID string // @id:type
type OrderID string // @id:type
`
	fp := writeTestFile(t, dir, "models.go", src)

	ids, pkg, err := processIDFile(dir, fp, false)
	tst.AssertNoErr(t, err)
	tst.AssertEqual(t, pkg, "mymodels")
	tst.AssertEqual(t, len(ids), 2)
	tst.AssertEqual(t, ids[0].Name, "UserID")
	tst.AssertEqual(t, ids[1].Name, "OrderID")
	tst.AssertEqual(t, ids[0].FileRelative, "models.go")
}

func TestProcessIDFileNoMatches(t *testing.T) {
	dir := t.TempDir()

	src := `package x

type Foo string
type Bar int
type Baz string // not the right marker
`
	fp := writeTestFile(t, dir, "x.go", src)

	ids, pkg, err := processIDFile(dir, fp, false)
	tst.AssertNoErr(t, err)
	tst.AssertEqual(t, pkg, "x")
	tst.AssertEqual(t, len(ids), 0)
}

func TestProcessIDFileGeneratedHeaderSkipped(t *testing.T) {
	dir := t.TempDir()

	src := `// Code generated by id-generate.go DO NOT EDIT.

package x

type SkipMeID string // @id:type
`
	fp := writeTestFile(t, dir, "skip.go", src)

	ids, pkg, err := processIDFile(dir, fp, false)
	tst.AssertNoErr(t, err)
	tst.AssertEqual(t, pkg, "")
	tst.AssertEqual(t, len(ids), 0)
}

func TestProcessIDFileMissingFile(t *testing.T) {
	_, _, err := processIDFile(t.TempDir(), filepath.Join(t.TempDir(), "does_not_exist.go"), false)
	tst.AssertTrue(t, err != nil)
}

func TestGenerateIDSpecsEndToEnd(t *testing.T) {
	dir := t.TempDir()

	src1 := `package models

type UserID string // @id:type
type AnyID string // @id:type
`
	writeTestFile(t, dir, "a_models.go", src1)

	src2 := `package models

type OrderID string // @id:type
`
	writeTestFile(t, dir, "b_models.go", src2)

	dest := filepath.Join(dir, "id_gen.go")

	err := GenerateIDSpecs(dir, dest, IDGenOptions{DebugOutput: langext.PFalse})
	tst.AssertNoErr(t, err)

	out, err := os.ReadFile(dest)
	tst.AssertNoErr(t, err)
	outStr := string(out)

	tst.AssertTrue(t, strings.Contains(outStr, "package models"))
	tst.AssertTrue(t, strings.Contains(outStr, "ChecksumIDGenerator"))
	tst.AssertTrue(t, strings.Contains(outStr, "func NewUserID()"))
	tst.AssertTrue(t, strings.Contains(outStr, "func NewOrderID()"))
	tst.AssertTrue(t, strings.Contains(outStr, "func NewAnyID()"))
	tst.AssertTrue(t, strings.Contains(outStr, "AsAny()"))
}

func TestGenerateIDSpecsIdempotentWhenUnchanged(t *testing.T) {
	dir := t.TempDir()

	src := `package models

type SomeID string // @id:type
`
	writeTestFile(t, dir, "models.go", src)
	dest := filepath.Join(dir, "id_gen.go")

	err := GenerateIDSpecs(dir, dest, IDGenOptions{})
	tst.AssertNoErr(t, err)

	stat1, err := os.Stat(dest)
	tst.AssertNoErr(t, err)

	content1, err := os.ReadFile(dest)
	tst.AssertNoErr(t, err)

	err = GenerateIDSpecs(dir, dest, IDGenOptions{})
	tst.AssertNoErr(t, err)

	stat2, err := os.Stat(dest)
	tst.AssertNoErr(t, err)

	content2, err := os.ReadFile(dest)
	tst.AssertNoErr(t, err)

	tst.AssertEqual(t, stat1.ModTime().Equal(stat2.ModTime()), true)
	tst.AssertEqual(t, string(content1), string(content2))
}

func TestGenerateIDSpecsRegeneratesAfterChange(t *testing.T) {
	dir := t.TempDir()

	src := `package models

type FirstID string // @id:type
`
	fp := writeTestFile(t, dir, "models.go", src)
	dest := filepath.Join(dir, "id_gen.go")

	err := GenerateIDSpecs(dir, dest, IDGenOptions{})
	tst.AssertNoErr(t, err)

	content1, err := os.ReadFile(dest)
	tst.AssertNoErr(t, err)
	tst.AssertTrue(t, strings.Contains(string(content1), "FirstID"))
	tst.AssertFalse(t, strings.Contains(string(content1), "SecondID"))

	src2 := `package models

type FirstID string // @id:type
type SecondID string // @id:type
`
	err = os.WriteFile(fp, []byte(src2), 0o644)
	tst.AssertNoErr(t, err)

	err = GenerateIDSpecs(dir, dest, IDGenOptions{})
	tst.AssertNoErr(t, err)

	content2, err := os.ReadFile(dest)
	tst.AssertNoErr(t, err)
	tst.AssertTrue(t, strings.Contains(string(content2), "SecondID"))
}

func TestGenerateIDSpecsErrorsWithoutPackage(t *testing.T) {
	dir := t.TempDir()

	src := `// Code generated by id-generate.go DO NOT EDIT.

package x

type SkippedID string // @id:type
`
	writeTestFile(t, dir, "z.go", src)
	dest := filepath.Join(dir, "id_gen.go")

	err := GenerateIDSpecs(dir, dest, IDGenOptions{})
	tst.AssertTrue(t, err != nil)
}

func TestGenerateIDSpecsMissingDir(t *testing.T) {
	dir := filepath.Join(t.TempDir(), "definitely-missing")
	err := GenerateIDSpecs(dir, filepath.Join(dir, "id_gen.go"), IDGenOptions{})
	tst.AssertTrue(t, err != nil)
}

func TestFmtIDOutputContainsAllNames(t *testing.T) {
	ids := []IDDef{
		{File: "a.go", FileRelative: "a.go", Name: "AlphaID"},
		{File: "b.go", FileRelative: "b.go", Name: "BetaID"},
	}
	out := fmtIDOutput("CHK_ABC", ids, "models")
	tst.AssertTrue(t, strings.Contains(out, "package models"))
	tst.AssertTrue(t, strings.Contains(out, "CHK_ABC"))
	tst.AssertTrue(t, strings.Contains(out, "AlphaID"))
	tst.AssertTrue(t, strings.Contains(out, "BetaID"))
}