package config

import (
	"fmt"
	"os"

	"gopkg.in/yaml.v3"
)

// Load runs one orchestration or CLI step.
// Signature: Load(path string) (Config, error).
// Why: keeps behavior explicit so startup/shutdown workflows remain maintainable as services evolve.
func Load(path string) (Config, error) {
	cfg := defaults()

	b, err := os.ReadFile(path)
	if err != nil {
		return Config{}, fmt.Errorf("read config %s: %w", path, err)
	}
	startupProbeRepairConfigured, err := yamlPathExists(b, "startup", "critical_service_startup_probe_repair")
	if err != nil {
		return Config{}, fmt.Errorf("decode config %s: %w", path, err)
	}
	if err := yaml.Unmarshal(b, &cfg); err != nil {
		return Config{}, fmt.Errorf("decode config %s: %w", path, err)
	}

	cfg.applyDefaults()
	if !startupProbeRepairConfigured {
		cfg.Startup.CriticalServiceStartupProbeRepair = defaults().Startup.CriticalServiceStartupProbeRepair
	}
	if err := cfg.Validate(); err != nil {
		return Config{}, err
	}
	return cfg, nil
}

// yamlPathExists runs one orchestration or CLI step.
// Signature: yamlPathExists(raw []byte, path ...string) (bool, error).
// Why: selected boolean defaults need to distinguish an omitted YAML key from an
// explicit false value after nested startup mappings are decoded.
func yamlPathExists(raw []byte, path ...string) (bool, error) {
	var root yaml.Node
	if err := yaml.Unmarshal(raw, &root); err != nil {
		return false, err
	}
	node := &root
	if node.Kind == yaml.DocumentNode && len(node.Content) > 0 {
		node = node.Content[0]
	}
	for _, key := range path {
		if node.Kind != yaml.MappingNode {
			return false, nil
		}
		found := false
		for i := 0; i+1 < len(node.Content); i += 2 {
			if node.Content[i].Value == key {
				node = node.Content[i+1]
				found = true
				break
			}
		}
		if !found {
			return false, nil
		}
	}
	return true, nil
}