package runtime

import (
	"context"
	"encoding/json"
	"fmt"
	"os"
	"path/filepath"
	"strings"
	"sync"

	"agent-native/adapters/native"
	"agent-native/runtime/tools"
	core "agent-system-core"
)

// kernelToolNames 是内核工作区自带的工具。同名宿主工具不注入，避免步骤因冲突失败。
var kernelToolNames = map[string]bool{
	"read_file": true, "write_file": true, "edit_file": true, "multi_edit": true,
	"list_dir": true, "grep": true, "glob": true, "load_skill": true,
	"run_python": true, "run_command": true, "web_search": true, "tavily_search": true,
	"fetch_url": true, "delegate_task": true,
}

type producedSink interface {
	add(ref *core.ArtifactRef)
}

// artifactList 是本次运行已登记的工件表。宿主工具可能被内核并行调用，
// 因此写入与读取都在同一把锁下：并发调用既不丢条目也不读到半成品。
type artifactList struct {
	mu    sync.Mutex
	items []*core.ArtifactRef
}

func (a *artifactList) add(ref *core.ArtifactRef) {
	if ref == nil {
		return
	}
	a.mu.Lock()
	defer a.mu.Unlock()
	a.items = append(a.items, ref)
}

// snapshot 返回当前工件的副本，供终局检查与部件装配使用。
func (a *artifactList) snapshot() []*core.ArtifactRef {
	if a == nil {
		return nil
	}
	a.mu.Lock()
	defer a.mu.Unlock()
	return append([]*core.ArtifactRef(nil), a.items...)
}

// bridgeHostTools 把画像允许的产品工具包成内核宿主工具。
// register_artifact 会先把内核步骤目录里的文件复制到会话工作区。
func bridgeHostTools(rc RunCtx, produced *artifactList) []tools.Tool {
	if produced == nil {
		produced = &artifactList{}
	}
	policy := rc.Profile().Tools
	var out []tools.Tool
	for _, desc := range rc.Tools() {
		if desc.Hidden || kernelToolNames[desc.Name] || !policy.ToolAllowed(desc.Name) {
			continue
		}
		out = append(out, &bridgedTool{rc: rc, desc: desc, produced: produced})
	}
	if rc.Settings().GetBool("ui.cardflow", false) {
		for _, desc := range cardToolDescs() {
			if policy.ToolAllowed(desc.Name) {
				out = append(out, &bridgedTool{rc: rc, desc: desc, produced: produced, card: true})
			}
		}
	}
	return out
}

type bridgedTool struct {
	rc       RunCtx
	desc     core.ToolDesc
	produced *artifactList
	card     bool
}

func (b *bridgedTool) Name() string                { return b.desc.Name }
func (b *bridgedTool) Description() string         { return b.desc.Description }
func (b *bridgedTool) Parameters() json.RawMessage { return b.desc.Parameters }

func (b *bridgedTool) Execute(ctx context.Context, args json.RawMessage) (tools.Result, error) {
	if b.desc.Name == "register_artifact" {
		stageStepFile(ctx, conversationSandbox(b.rc), args)
	}
	if b.card {
		out, err := executeCardTool(b.rc, b.desc.Name, args)
		if err != nil {
			return tools.Result{Content: err.Error(), IsError: true}, nil
		}
		return tools.Result{Content: out}, nil
	}
	res := b.rc.ExecuteTool(core.ToolCallRequest{Name: b.desc.Name, Arguments: args})
	if res.Artifact != nil {
		b.produced.add(&core.ArtifactRef{ArtifactID: res.Artifact.ID, Name: res.Artifact.Name, Kind: res.Artifact.Kind})
	}
	if res.Status != "ok" {
		return tools.Result{Content: res.Output, IsError: true}, nil
	}
	return tools.Result{Content: res.Output}, nil
}

func conversationSandbox(rc RunCtx) string {
	s, ok := rc.(interface{ ConversationSandbox() string })
	if !ok {
		return ""
	}
	return s.ConversationSandbox()
}

func stageStepFile(ctx context.Context, sandbox string, args json.RawMessage) {
	step := native.WorkDir(ctx)
	if step == "" || sandbox == "" {
		return
	}
	var a struct {
		Path string `json:"path"`
	}
	if json.Unmarshal(args, &a) != nil || strings.TrimSpace(a.Path) == "" || strings.Contains(a.Path, "..") {
		return
	}
	src := filepath.Join(step, filepath.FromSlash(a.Path))
	dst := filepath.Join(sandbox, filepath.FromSlash(a.Path))
	if _, err := os.Stat(dst); err == nil {
		return
	}
	body, err := os.ReadFile(src)
	if err != nil {
		return
	}
	if os.MkdirAll(filepath.Dir(dst), 0o755) != nil {
		return
	}
	_ = os.WriteFile(dst, body, 0o644)
}

func cardToolDescs() []core.ToolDesc {
	return []core.ToolDesc{
		{Name: toolCard, Description: "提交产物卡片", Parameters: json.RawMessage(`{"type":"object","properties":{"title":{"type":"string"},"summary":{"type":"string"},"body":{"type":"string"},"scope":{"type":"string"}},"required":["title","body"]}`)},
		{Name: toolCardBegin, Description: "开始流式产物卡", Parameters: json.RawMessage(`{"type":"object","properties":{"title":{"type":"string"},"summary":{"type":"string"},"scope":{"type":"string"}},"required":["title"]}`)},
		{Name: toolCardAppend, Description: "追加流式产物卡", Parameters: json.RawMessage(`{"type":"object","properties":{"text":{"type":"string"}},"required":["text"]}`)},
		{Name: toolCardCommit, Description: "收尾流式产物卡", Parameters: json.RawMessage(`{"type":"object","properties":{}}`)},
	}
}

func executeCardTool(rc RunCtx, name string, args json.RawMessage) (string, error) {
	switch name {
	case toolCard:
		var a struct{ Title, Summary, Body, Scope string }
		if err := json.Unmarshal(args, &a); err != nil || strings.TrimSpace(a.Title) == "" || strings.TrimSpace(a.Body) == "" {
			return "", fmt.Errorf("submit_card 参数错误")
		}
		card := core.ActivityCard{Kind: core.CardKindResult, Title: a.Title, Status: core.CardDone, Tone: "ok", Body: []core.UINode{{Type: "markdown", Markdown: a.Body}}}
		if a.Scope == "project" {
			card.ProjectID = core.ID(rc.Run().ProjectID)
		}
		created, err := rc.SubmitCard(card)
		if err != nil {
			return "", err
		}
		return "已作为卡片发出（" + created.Title + "）", nil
	case toolCardBegin:
		var a struct{ Title, Summary, Scope string }
		if err := json.Unmarshal(args, &a); err != nil || strings.TrimSpace(a.Title) == "" {
			return "", fmt.Errorf("card_begin 参数错误")
		}
		card := core.ActivityCard{Kind: core.CardKindResult, Title: a.Title, Status: core.CardActive, Tone: "ok"}
		if a.Scope == "project" {
			card.ProjectID = core.ID(rc.Run().ProjectID)
		}
		created, err := rc.BeginStreamCard(card)
		if err != nil {
			return "", err
		}
		return "流式卡已开始（" + created.Title + "）", nil
	case toolCardAppend:
		var a struct{ Text string }
		if err := json.Unmarshal(args, &a); err != nil {
			return "", err
		}
		if err := rc.AppendStreamCard(a.Text); err != nil {
			return "", err
		}
		return "已追加", nil
	case toolCardCommit:
		card, err := rc.CommitStreamCard()
		if err != nil {
			return "", err
		}
		return "已作为卡片发出（" + card.Title + "）", nil
	default:
		return "", nil
	}
}