package forwardplugin

import (
	"encoding/json"
	"fmt"
	"strings"
)

func ValidateAndNormalizePlugins(entries []PluginEntry) ([]PluginEntry, error) {
	if len(entries) == 0 {
		return nil, nil
	}
	out := make([]PluginEntry, 0, len(entries))
	for i, e := range entries {
		typ := strings.TrimSpace(e.Type)
		if typ == "" {
			return nil, fmt.Errorf("plugins[%d].type 不能为空", i)
		}
		factory, ok := getFactory(typ)
		if !ok {
			return nil, fmt.Errorf("未知插件类型: %s", typ)
		}
		cfg := e.Config
		if len(cfg) == 0 {
			cfg = json.RawMessage("{}")
		}
		p, err := factory(cfg)
		if err != nil {
			return nil, fmt.Errorf("plugins[%d]: %w", i, err)
		}
		if err := p.ValidateConfig(cfg); err != nil {
			return nil, fmt.Errorf("plugins[%d]: %w", i, err)
		}
		normalized, err := normalizeConfig(cfg, p)
		if err != nil {
			return nil, fmt.Errorf("plugins[%d]: %w", i, err)
		}
		out = append(out, PluginEntry{
			Type:    typ,
			Enabled: e.Enabled,
			Config:  normalized,
		})
	}
	return out, nil
}

func normalizeConfig(raw json.RawMessage, p Plugin) (json.RawMessage, error) {
	if norm, ok := p.(ConfigNormalizer); ok {
		return norm.NormalizeConfig(raw)
	}
	return raw, nil
}

type ConfigNormalizer interface {
	NormalizeConfig(raw json.RawMessage) (json.RawMessage, error)
}

func BuildChain(entries []PluginEntry) (*Chain, error) {
	plugins := make([]Plugin, 0, len(entries))
	for _, e := range entries {
		if !e.Enabled {
			continue
		}
		factory, ok := getFactory(e.Type)
		if !ok {
			return nil, fmt.Errorf("未知插件类型: %s", e.Type)
		}
		cfg := e.Config
		if len(cfg) == 0 {
			cfg = json.RawMessage("{}")
		}
		p, err := factory(cfg)
		if err != nil {
			return nil, err
		}
		plugins = append(plugins, p)
	}
	return &Chain{plugins: plugins}, nil
}

func PluginsJSON(entries []PluginEntry) string {
	if len(entries) == 0 {
		return "[]"
	}
	b, _ := json.Marshal(entries)
	return string(b)
}