package app

import (
	"encoding/json"
	"os"
	"path/filepath"
)

// prefs is the TUI's local, persisted preferences (display-only client state — kept out
// of the server config, which is shared/replayed). Stored as JSON in the correx config dir.
type prefs struct {
	StatusbarHidden []string `json:"statusbarHidden"`
}

// statusSegment is one toggleable status-bar segment. The always-on segments (correx label,
// connection, session name, spinner, background-updates) are not listed — they are load-bearing.
type statusSegment struct{ id, label string }

var statusSegments = []statusSegment{
	{"stage", "current stage (⟐)"},
	{"status", "session status"},
	{"workspace", "workspace path (⌂)"},
	{"model", "model name"},
	{"clock", "last-event clock"},
	{"gauge", "resource gauge"},
}

func prefsPath() string {
	dir := os.Getenv("CORREX_CONFIG_HOME")
	if dir == "" {
		home, err := os.UserHomeDir()
		if err != nil {
			return ""
		}
		dir = filepath.Join(home, ".config", "correx")
	}
	return filepath.Join(dir, "tui-prefs.json")
}

// loadStatusbarHidden reads the persisted hidden-segment set (best-effort: a missing or
// corrupt file yields an empty set, i.e. everything shown).
func loadStatusbarHidden() map[string]bool {
	out := map[string]bool{}
	path := prefsPath()
	if path == "" {
		return out
	}
	data, err := os.ReadFile(path)
	if err != nil {
		return out
	}
	var p prefs
	if json.Unmarshal(data, &p) == nil {
		for _, id := range p.StatusbarHidden {
			out[id] = true
		}
	}
	return out
}

// saveStatusbarHidden writes the hidden set back to disk (best-effort; ignores IO errors so
// a read-only home never crashes the UI). Order follows statusSegments for a stable file.
func saveStatusbarHidden(hidden map[string]bool) {
	path := prefsPath()
	if path == "" {
		return
	}
	var ids []string
	for _, seg := range statusSegments {
		if hidden[seg.id] {
			ids = append(ids, seg.id)
		}
	}
	if err := os.MkdirAll(filepath.Dir(path), 0o755); err != nil {
		return
	}
	if data, err := json.MarshalIndent(prefs{StatusbarHidden: ids}, "", "  "); err == nil {
		_ = os.WriteFile(path, data, 0o644)
	}
}