package cli

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

	"agent-squad/squad"
)

// demoBackend 脚本化后端：按子工作区目录名回放预设产出（离线演示/测试）。
type demoBackend struct {
	// script: 子目录名（如 01_researcher）→ target → 文件内容。
	script map[string]map[string]string
}

func (b *demoBackend) Name() string { return "demo" }

func (b *demoBackend) Execute(ctx context.Context, req squad.ExecRequest) (*squad.ExecResult, error) {
	key := filepath.Base(filepath.Clean(req.WorkDir))
	files, ok := b.script[key]
	if !ok {
		// 未脚本化的步骤退化为写一个说明文件到首个 target。
		files = map[string]string{}
		for i, t := range req.Targets {
			if i == 0 {
				files[t] = fmt.Sprintf("# 演示产出\n\n步骤目录 %s 未脚本化，这是默认产出。\n", key)
			}
		}
	}
	patches := map[string][]byte{}
	for _, t := range req.Targets {
		content := files[t]
		if content == "" {
			content = "\n"
		}
		out := filepath.Join(req.WorkDir, t)
		_ = os.MkdirAll(filepath.Dir(out), 0o755)
		if err := os.WriteFile(out, []byte(content), 0o644); err != nil {
			return nil, err
		}
		patches[t] = []byte(content)
	}
	return &squad.ExecResult{Success: true, Patches: patches, Logs: "demo backend replay"}, nil
}

// cmdDemo 离线全链路演示：注册角色 → 规划 → 执行 → HITL 阻塞缺口挂起 →
// 人工回应 → 继续 → 质检 → 交付。全程 stub/脚本驱动，无需模型与外部智能体。
func cmdDemo(args []string) int {
	fs := flag.NewFlagSet("demo", flag.ContinueOnError)
	keep := fs.Bool("keep", false, "保留演示数据目录")
	if err := fs.Parse(args); err != nil {
		return 2
	}
	dir, err := os.MkdirTemp("", "agent-squad-demo-")
	if err != nil {
		fmt.Fprintln(os.Stderr, err)
		return 1
	}
	defer func() {
		if *keep {
			fmt.Println("\n演示工作区保留于:", dir)
		} else {
			_ = os.RemoveAll(dir)
		}
	}()

	fmt.Println("═══ agent-squad 离线演示（stub 智能体 + mock 规划器 + HITL）═══")
	fmt.Println("数据目录:", dir)

	// 1. 组装：空注册表起步。
	reg := squad.NewRoleRegistry()
	bps := squad.NewBlueprintRegistry()
	backends := squad.NewBackendResolver()
	demoScript := map[string]map[string]string{
		"01_researcher": {
			"notes.md":    "# 调研笔记\n\n- 目标产品：便携式超声诊断仪\n- 竞品：A/B/C 三款\n- 法规路径：二类器械，注册检验 + 临床评价\n",
			"fields.json": `{"target_market":"中国","device_class":"二类","budget":"15万"}`,
			"gaps.json":   `[{"item":"目标年产量未提供，影响成本测算","blocking":true}]`,
		},
		"02_writer": {
			"output.md": "# 便携式超声诊断仪调研报告\n\n## 概述与背景\n\n本报告基于输入材料与调研产出，梳理便携式超声诊断仪的市场与技术背景。目标市场为中国（二类器械），预算 15 万元。\n\n## 核心内容\n\n竞品 A/B/C 在成像质量与便携性上各有取舍；技术路线建议探头一体化设计与电池供电优化。注册路径按二类器械执行注册检验与临床评价。\n\n## 风险与注意事项\n\n- 供应链对探头晶片依赖较高\n- 注册周期受检验排队影响\n\n## 基准假设与待确认清单\n\n- 年产量按人工澄清结论执行\n",
		},
		"03_reviewer": {
			"output.md":   "# 便携式超声诊断仪调研报告（终审版）\n\n## 概述与背景\n\n本报告由小队协作产出：调研专员梳理事实与缺口，撰写专员成文，审核专员终审。目标市场为中国（二类器械），预算 15 万元，年产量 10 万套。\n\n## 核心内容\n\n竞品 A/B/C 在成像质量与便携性上各有取舍；技术路线建议探头一体化设计与电池供电优化。注册路径按二类器械执行注册检验与临床评价。成本测算基于年产量 10 万套摊薄产线投入。\n\n## 风险与注意事项\n\n- 供应链对探头晶片依赖较高\n- 注册周期受检验排队影响\n- 年产量波动超过 ±30% 时需重估成本模型\n\n## 基准假设与待确认清单\n\n- 灭菌方式采用环氧乙烷（EO）灭菌（行业常规）\n",
			"fields.json": `{"annual_volume":"100000","review":"passed"}`,
		},
	}
	backends.RegisterInstance("demo", &demoBackend{script: demoScript})

	planner := &squad.MockPlanner{Script: []squad.StepSpec{
		{ID: "step_01_research", Role: "researcher", Title: "市场与技术调研，回填事实与缺口",
			Targets: []string{"notes.md", "fields.json", "gaps.json"}},
		{ID: "step_02_draft", Role: "writer", Title: "汇总调研产出，撰写报告初稿",
			Targets: []string{"output.md"}},
		{ID: "step_03_review", Role: "reviewer", Title: "一致性终审并产出终版",
			Targets: []string{"output.md", "fields.json"}},
	}}
	sink := squad.NewFanoutSink(4096)
	engine, err := squad.NewEngine(squad.Options{
		DataDir: dir, Registry: reg, Blueprints: bps, Planner: planner,
		Backends: backends, Sink: sink,
	})
	if err != nil {
		fmt.Fprintln(os.Stderr, "组装失败:", err)
		return 1
	}

	// 2. 注册角色（演示小队编制——底座本身无预设角色）。
	fmt.Println("\n[1] 注册角色（手动注册，backend=demo 脚本智能体）")
	for _, spec := range []squad.RoleSpec{
		{Role: "researcher", Name: "调研专员", Backend: "demo", Keywords: []string{"调研", "市场", "竞品"},
			Responsibilities: []string{"市场与技术调研", "事实回填"}},
		{Role: "writer", Name: "撰写专员", Backend: "demo", Keywords: []string{"撰写", "报告"},
			Responsibilities: []string{"汇总产出并成文"}},
		{Role: "reviewer", Name: "审核专员", Backend: "demo", Keywords: []string{"审核", "终审"},
			Responsibilities: []string{"一致性终审"}},
	} {
		if err := reg.Register(spec); err != nil {
			fmt.Fprintln(os.Stderr, err)
			return 1
		}
		fmt.Printf("    + %-12s %s\n", spec.Role, spec.Name)
	}

	// 3. 发起运行。
	goal := squad.Goal{Text: "调研便携式超声诊断仪并产出报告"}
	fmt.Printf("\n[2] 发起运行：%s\n", goal.Text)
	res, err := engine.Run(context.Background(), goal, squad.RunOptions{})
	if err != nil {
		fmt.Fprintln(os.Stderr, "运行失败:", err)
		return 1
	}
	reportSteps(res)

	// 4. HITL 挂起 → 回应 → 续跑。
	for res.Status.IsHeld() && res.Pending != nil {
		fmt.Printf("\n[3] ⏸ HITL 挂起（%s）：%s\n", res.Pending.Kind, res.Pending.Question)
		for _, line := range strings.Split(res.Pending.Context, "\n") {
			if line != "" {
				fmt.Println("     ", line)
			}
		}
		answer := demoAnswer(res.Pending)
		fmt.Printf("     → 自动回应：choice=%q answer=%q\n", answer.Choice, answer.Answer)
		res, err = engine.Respond(context.Background(), res.RunID, answer)
		if err != nil {
			fmt.Fprintln(os.Stderr, "回应失败:", err)
			return 1
		}
		reportSteps(res)
	}

	// 5. 结果。
	fmt.Printf("\n[4] 运行终态：%s\n", res.Status)
	if res.Summary != "" {
		fmt.Println("   ", res.Summary)
	}
	if res.Deliverable != "" {
		path := filepath.Join(res.WorkDir, res.Deliverable)
		fmt.Println("    交付物:", path)
		if head := headLines(path, 6); head != "" {
			fmt.Println("    ┌─ 交付物预览")
			for _, l := range strings.Split(strings.TrimRight(head, "\n"), "\n") {
				fmt.Println("    │", l)
			}
			fmt.Println("    └─")
		}
	}
	bb, _ := engine.Blackboard(res.RunID)
	if bb != nil {
		enc, _ := json.MarshalIndent(bb.Fields, "", "  ")
		fmt.Println("    黑板字段:", string(enc))
	}
	fmt.Println("\n演示完成。真实使用：agent-squad role add / run / serve。")
	return 0
}

func demoAnswer(req *squad.HumanRequest) squad.RespondDecision {
	switch req.Kind {
	case squad.HitlGap:
		return squad.RespondDecision{RequestID: req.ID, Choice: "resolved", Answer: "年产量 10 万套"}
	default:
		choice := "approve"
		if len(req.Options) > 0 {
			choice = req.Options[0].Value
		}
		return squad.RespondDecision{RequestID: req.ID, Choice: choice}
	}
}

func reportSteps(res *squad.RunResult) {
	if res.Plan == nil {
		return
	}
	for _, s := range res.Plan.Steps {
		mark := map[string]string{"completed": "✔", "failed": "✘", "skipped": "⤼", "running": "…", "pending": " "}[s.Status]
		fmt.Printf("    %s %-22s %-12s %s\n", mark, s.ID, s.Role, s.Title)
	}
}

func headLines(path string, n int) string {
	data, err := os.ReadFile(path)
	if err != nil {
		return ""
	}
	lines := strings.Split(string(data), "\n")
	if len(lines) > n {
		lines = lines[:n]
	}
	return strings.Join(lines, "\n")
}