// Package stack — manajemen stack & konverter docker run → compose.
//
// Converter ini adalah hasil porting perilaku composerize (MIT) yang
// dispesifikasikan di docs/rea/composerize.md — tulis ulang, bukan salin.
package stack

import (
	"fmt"
	"regexp"
	"strings"

	"gopkg.in/yaml.v3"
)

// ConvertResult — hasil konversi.
// Output = teks siap cetak (komentar warning + YAML).
type ConvertResult struct {
	Output      string
	ServiceName string
	Warnings    []string
}

// Convert — porting pipeline composerize:
// normalisasi → tokenisasi → klasifikasi flag → mapping → post-processing →
// emit YAML common-spec (tanpa `version:`, indent 2).
func Convert(cmd string) (ConvertResult, error) {
	input := normalize(cmd)

	body, ok := stripCommandPrefix(input)
	if !ok {
		return ConvertResult{}, fmt.Errorf("bukan perintah docker/podman run: %q", strings.TrimSpace(cmd))
	}

	tokens := tokenize(body)
	order, params, positionals := parseTokens(tokens)

	if len(positionals) == 0 {
		return ConvertResult{}, fmt.Errorf("docker run: image tidak ditemukan")
	}
	image := stripQuotes(positionals[0])
	serviceName := serviceNameFromImage(image)

	svc, warns, err := buildService(order, params, serviceName)
	if err != nil {
		return ConvertResult{}, err
	}

	// image & command ditambahkan terakhir (urutan key mengikuti referensi).
	svc.set("image", strNode(image))
	if len(positionals) > 1 {
		svc.set("command", strNode(strings.Join(positionals[1:], " ")))
	}

	// network_mode host → ports dibuang (parity referensi).
	if svc.has("network_mode") && svc.get("network_mode").Value == "host" {
		svc.del("ports")
	}

	res := ConvertResult{ServiceName: serviceName, Warnings: warns}
	top, extraWarn := finishTopLevel(svc, serviceName)
	res.Warnings = append(res.Warnings, extraWarn...)

	doc := &yaml.Node{Kind: yaml.DocumentNode}
	doc.Content = []*yaml.Node{top}

	var sb strings.Builder
	for _, w := range res.Warnings {
		sb.WriteString("# " + w + "\n")
	}
	enc := yaml.NewEncoder(&sb)
	enc.SetIndent(2)
	if err := enc.Encode(doc); err != nil {
		return ConvertResult{}, fmt.Errorf("emit yaml: %w", err)
	}
	_ = enc.Close()
	res.Output = strings.TrimRight(sb.String(), "\n")
	return res, nil
}

// --- normalisasi (urutan persis mengikuti referensi) ---

var (
	reComments = regexp.MustCompile(`\n\s*#[^\n]*`)
	reShellSub = regexp.MustCompile(`\$\([^)]*\)`)
	rePfix     = regexp.MustCompile(`\s-p(\d)`)
	reSpaces   = regexp.MustCompile(`(\s)+`)
	reSpBslash = regexp.MustCompile(`\s\\\s`)
	reSemi     = regexp.MustCompile(`\s*;$`)
	rePrefix   = regexp.MustCompile(`^(?:\s*\$\s+)?(?:docker|podman)\s+(run|create|container\s+run|service\s+create)\s+`)
)

func normalize(s string) string {
	s = strings.ReplaceAll(s, "\\\n", "")
	s = reComments.ReplaceAllString(s, "")
	s = reShellSub.ReplaceAllStringFunc(s, func(m string) string {
		return strings.ReplaceAll(m, " ", "\u00a4") // lindungi spasi dalam $(...)
	})
	s = reSpaces.ReplaceAllString(s, " ")
	s = strings.TrimSpace(s)
	s = rePfix.ReplaceAllString(s, " -p $1")
	s = reSpBslash.ReplaceAllString(s, " ")
	s = reSemi.ReplaceAllString(s, "")
	return s
}

func stripCommandPrefix(s string) (string, bool) {
	if m := rePrefix.FindString(s); m != "" {
		return s[len(m):], true
	}
	return "", false
}

// --- tokenisasi (quote-aware; kutip dibuang seperti shell) ---

func tokenize(s string) []string {
	var tokens []string
	var cur strings.Builder
	quote := rune(0)
	flush := func() {
		if cur.Len() > 0 {
			tokens = append(tokens, cur.String())
			cur.Reset()
		}
	}
	for _, r := range s {
		switch {
		case quote != 0:
			if r == quote {
				quote = 0
			} else {
				cur.WriteRune(r)
			}
		case r == '\'' || r == '"':
			quote = r
		case r == ' ' || r == '\t':
			flush()
		default:
			cur.WriteRune(r)
		}
	}
	flush()
	return tokens
}

// --- klasifikasi token → key: values + positional (halt-at-non-option) ---

// booleanFlags — daftar persis dari referensi (token tanpa nilai).
var booleanFlags = map[string]bool{
	"i": true, "interactive": true, "t": true, "tty": true,
	"d": true, "detach": true, "rm": true, "init": true, "help": true,
	"privileged": true, "P": true, "publish-all": true,
	"no-healthcheck": true, "oom-kill-disable": true, "read-only": true,
	"sig-proxy": true,
}

func parseTokens(tokens []string) ([]string, map[string][]string, []string) {
	params := map[string][]string{}
	var order []string // urutan kemunculan key (emit deterministik)
	var positionals []string
	positionalMode := false

	add := func(k, v string) {
		if _, seen := params[k]; !seen {
			order = append(order, k)
		}
		params[k] = append(params[k], v)
	}

	for i := 0; i < len(tokens); i++ {
		tok := tokens[i]
		if positionalMode || !strings.HasPrefix(tok, "-") || tok == "-" {
			positionalMode = true // halt-at-non-option
			positionals = append(positionals, tok)
			continue
		}
		switch {
		case tok == "--":
			positionalMode = true
		case strings.HasPrefix(tok, "--"):
			body := tok[2:]
			if k, v, ok := strings.Cut(body, "="); ok {
				add(k, v)
				continue
			}
			if booleanFlags[body] {
				add(body, "true")
				continue
			}
			// ambil token berikut sebagai nilai bila bukan opsi lain
			if i+1 < len(tokens) && !strings.HasPrefix(tokens[i+1], "-") {
				i++
				add(body, tokens[i])
			} else {
				add(body, "true")
			}
		default: // "-x", "-xVALUE", "-it" (cluster boolean)
			body := tok[1:]
			if len(body) == 0 {
				continue
			}
			if len(body) == 1 {
				if booleanFlags[body] {
					add(body, "true")
					continue
				}
				if i+1 < len(tokens) && !strings.HasPrefix(tokens[i+1], "-") {
					i++
					add(body, tokens[i])
				} else {
					add(body, "true")
				}
				continue
			}
			// semua karakter boolean → cluster; selain itu key=char pertama
			allBool := true
			for _, c := range body {
				if !booleanFlags[string(c)] {
					allBool = false
					break
				}
			}
			if allBool {
				for _, c := range body {
					add(string(c), "true")
				}
			} else {
				add(string(body[0]), body[1:])
			}
		}
	}

	return order, params, positionals
}

// --- util nilai ---

func stripQuotes(v string) string {
	if len(v) >= 2 {
		first, last := v[0], v[len(v)-1]
		if (first == '\'' || first == '"') && last == first {
			v = v[1 : len(v)-1]
		}
	}
	return strings.ReplaceAll(v, "\u00a4", " ") // kembalikan spasi dalam $(...)
}

func serviceNameFromImage(image string) string {
	name := image
	if i := strings.LastIndex(name, "/"); i >= 0 {
		name = name[i+1:]
	}
	if i := strings.Index(name, ":"); i >= 0 {
		name = name[:i]
	}
	if name == "" {
		name = "service"
	}
	return name
}

func strNode(v string) *yaml.Node {
	return &yaml.Node{Kind: yaml.ScalarNode, Tag: "!!str", Value: v}
}

func intNode(v int) *yaml.Node {
	return &yaml.Node{Kind: yaml.ScalarNode, Tag: "!!int", Value: fmt.Sprintf("%d", v)}
}

func floatNode(v float64) *yaml.Node {
	return &yaml.Node{Kind: yaml.ScalarNode, Tag: "!!float", Value: trimFloat(v)}
}

func boolNode() *yaml.Node {
	return &yaml.Node{Kind: yaml.ScalarNode, Tag: "!!bool", Value: "true"}
}

func trimFloat(f float64) string {
	s := fmt.Sprintf("%v", f)
	return s
}