agent/pkg/agentic/prep.go

// SPDX-License-Identifier: EUPL-1.2

// Package agentic provides MCP tools for agent orchestration.
// Prepares sandboxed workspaces and dispatches subagents.
package agentic

import (
	"context"
	"encoding/base64"
	"encoding/json"
	"fmt"
	"io"
	"net/http"
	"os"
	"os/exec"
	"path/filepath"
	"strings"
	"time"

	coreio "forge.lthn.ai/core/go-io"
	coreerr "forge.lthn.ai/core/go-log"
	"github.com/modelcontextprotocol/go-sdk/mcp"
	"gopkg.in/yaml.v3"
)

// PrepSubsystem provides agentic MCP tools.
type PrepSubsystem struct {
	forgeURL    string
	forgeToken  string
	brainURL    string
	brainKey    string
	specsPath   string
	codePath    string
	client *http.Client
}

// NewPrep creates an agentic subsystem.
func NewPrep() *PrepSubsystem {
	home, _ := os.UserHomeDir()

	forgeToken := os.Getenv("FORGE_TOKEN")
	if forgeToken == "" {
		forgeToken = os.Getenv("GITEA_TOKEN")
	}

	brainKey := os.Getenv("CORE_BRAIN_KEY")
	if brainKey == "" {
		if data, err := coreio.Local.Read(filepath.Join(home, ".claude", "brain.key")); err == nil {
			brainKey = strings.TrimSpace(data)
		}
	}

	return &PrepSubsystem{
		forgeURL:    envOr("FORGE_URL", "https://forge.lthn.ai"),
		forgeToken:  forgeToken,
		brainURL:    envOr("CORE_BRAIN_URL", "https://api.lthn.sh"),
		brainKey:    brainKey,
		specsPath:   envOr("SPECS_PATH", filepath.Join(home, "Code", "host-uk", "specs")),
		codePath:    envOr("CODE_PATH", filepath.Join(home, "Code")),
		client: &http.Client{Timeout: 30 * time.Second},
	}
}

func envOr(key, fallback string) string {
	if v := os.Getenv(key); v != "" {
		return v
	}
	return fallback
}

// Name implements mcp.Subsystem.
func (s *PrepSubsystem) Name() string { return "agentic" }

// RegisterTools implements mcp.Subsystem.
func (s *PrepSubsystem) RegisterTools(server *mcp.Server) {
	mcp.AddTool(server, &mcp.Tool{
		Name:        "agentic_prep_workspace",
		Description: "Prepare a sandboxed agent workspace with TODO.md, CLAUDE.md, CONTEXT.md, CONSUMERS.md, RECENT.md, and a git clone of the target repo in src/.",
	}, s.prepWorkspace)

	s.registerDispatchTool(server)
	s.registerStatusTool(server)
	s.registerResumeTool(server)
	s.registerCreatePRTool(server)
	s.registerListPRsTool(server)
	s.registerEpicTool(server)

	mcp.AddTool(server, &mcp.Tool{
		Name:        "agentic_scan",
		Description: "Scan Forge repos for open issues with actionable labels (agentic, help-wanted, bug).",
	}, s.scan)

	s.registerPlanTools(server)
}

// Shutdown implements mcp.SubsystemWithShutdown.
func (s *PrepSubsystem) Shutdown(_ context.Context) error { return nil }

// --- Input/Output types ---

// PrepInput is the input for agentic_prep_workspace.
type PrepInput struct {
	Repo         string            `json:"repo"`                    // e.g. "go-io"
	Org          string            `json:"org,omitempty"`           // default "core"
	Issue        int               `json:"issue,omitempty"`         // Forge issue number
	Task         string            `json:"task,omitempty"`          // Task description (if no issue)
	Template     string            `json:"template,omitempty"`      // Prompt template: conventions, security, coding (default: coding)
	PlanTemplate string            `json:"plan_template,omitempty"` // Plan template slug: bug-fix, code-review, new-feature, refactor, feature-port
	Variables    map[string]string `json:"variables,omitempty"`     // Template variable substitution
	Persona      string            `json:"persona,omitempty"`       // Persona slug: engineering/backend-architect, testing/api-tester, etc.
}

// PrepOutput is the output for agentic_prep_workspace.
type PrepOutput struct {
	Success       bool   `json:"success"`
	WorkspaceDir  string `json:"workspace_dir"`
	Branch        string `json:"branch"`
	WikiPages     int    `json:"wiki_pages"`
	SpecFiles     int    `json:"spec_files"`
	Memories      int    `json:"memories"`
	Consumers     int    `json:"consumers"`
	ClaudeMd      bool   `json:"claude_md"`
	GitLog        int    `json:"git_log_entries"`
}

func (s *PrepSubsystem) prepWorkspace(ctx context.Context, _ *mcp.CallToolRequest, input PrepInput) (*mcp.CallToolResult, PrepOutput, error) {
	if input.Repo == "" {
		return nil, PrepOutput{}, coreerr.E("prepWorkspace", "repo is required", nil)
	}
	if input.Org == "" {
		input.Org = "core"
	}
	if input.Template == "" {
		input.Template = "coding"
	}

	// Workspace root: .core/workspace/{repo}-{timestamp}/
	home, _ := os.UserHomeDir()
	wsRoot := filepath.Join(home, "Code", "host-uk", "core", ".core", "workspace")
	wsName := fmt.Sprintf("%s-%d", input.Repo, time.Now().Unix())
	wsDir := filepath.Join(wsRoot, wsName)

	// Create workspace structure
	// kb/ and specs/ will be created inside src/ after clone

	out := PrepOutput{WorkspaceDir: wsDir}

	// Source repo path
	repoPath := filepath.Join(s.codePath, "core", input.Repo)

	// 1. Clone repo into src/ and create feature branch
	srcDir := filepath.Join(wsDir, "src")
	cloneCmd := exec.CommandContext(ctx, "git", "clone", repoPath, srcDir)
	cloneCmd.Run()

	// Create feature branch
	taskSlug := strings.Map(func(r rune) rune {
		if r >= 'a' && r <= 'z' || r >= '0' && r <= '9' || r == '-' {
			return r
		}
		if r >= 'A' && r <= 'Z' {
			return r + 32 // lowercase
		}
		return '-'
	}, input.Task)
	if len(taskSlug) > 40 {
		taskSlug = taskSlug[:40]
	}
	taskSlug = strings.Trim(taskSlug, "-")
	branchName := fmt.Sprintf("agent/%s", taskSlug)

	branchCmd := exec.CommandContext(ctx, "git", "checkout", "-b", branchName)
	branchCmd.Dir = srcDir
	branchCmd.Run()
	out.Branch = branchName

	// Create context dirs inside src/
	coreio.Local.EnsureDir(filepath.Join(srcDir, "kb"))
	coreio.Local.EnsureDir(filepath.Join(srcDir, "specs"))

	// Remote stays as local clone origin — agent cannot push to forge.
	// Reviewer pulls changes from workspace and pushes after verification.

	// 2. Copy CLAUDE.md and GEMINI.md to workspace
	claudeMdPath := filepath.Join(repoPath, "CLAUDE.md")
	if data, err := coreio.Local.Read(claudeMdPath); err == nil {
		coreio.Local.Write(filepath.Join(wsDir, "src", "CLAUDE.md"), data)
		out.ClaudeMd = true
	}
	// Copy GEMINI.md from core/agent (ethics framework for all agents)
	agentGeminiMd := filepath.Join(s.codePath, "core", "agent", "GEMINI.md")
	if data, err := coreio.Local.Read(agentGeminiMd); err == nil {
		coreio.Local.Write(filepath.Join(wsDir, "src", "GEMINI.md"), data)
	}

	// Copy persona if specified
	if input.Persona != "" {
		personaPath := filepath.Join(s.codePath, "core", "agent", "prompts", "personas", input.Persona+".md")
		if data, err := coreio.Local.Read(personaPath); err == nil {
			coreio.Local.Write(filepath.Join(wsDir, "src", "PERSONA.md"), data)
		}
	}

	// 3. Generate TODO.md
	if input.Issue > 0 {
		s.generateTodo(ctx, input.Org, input.Repo, input.Issue, wsDir)
	} else if input.Task != "" {
		todo := fmt.Sprintf("# TASK: %s\n\n**Repo:** %s/%s\n**Status:** ready\n\n## Objective\n\n%s\n",
			input.Task, input.Org, input.Repo, input.Task)
		coreio.Local.Write(filepath.Join(wsDir, "src", "TODO.md"), todo)
	}

	// 4. Generate CONTEXT.md from OpenBrain
	out.Memories = s.generateContext(ctx, input.Repo, wsDir)

	// 5. Generate CONSUMERS.md
	out.Consumers = s.findConsumers(input.Repo, wsDir)

	// 6. Generate RECENT.md
	out.GitLog = s.gitLog(repoPath, wsDir)

	// 7. Pull wiki pages into kb/
	out.WikiPages = s.pullWiki(ctx, input.Org, input.Repo, wsDir)

	// 8. Copy spec files into specs/
	out.SpecFiles = s.copySpecs(wsDir)

	// 9. Write PLAN.md from template (if specified)
	if input.PlanTemplate != "" {
		s.writePlanFromTemplate(input.PlanTemplate, input.Variables, input.Task, wsDir)
	}

	// 10. Write prompt template
	s.writePromptTemplate(input.Template, wsDir)

	out.Success = true
	return nil, out, nil
}

// --- Prompt templates ---

func (s *PrepSubsystem) writePromptTemplate(template, wsDir string) {
	var prompt string

	switch template {
	case "conventions":
		prompt = `## SANDBOX: You are restricted to this directory only. No absolute paths, no cd .., no editing outside src/.

Read CLAUDE.md for project conventions.
Review all Go files in src/ for:
- Error handling: should use coreerr.E() from go-log, not fmt.Errorf or errors.New
- Compile-time interface checks: var _ Interface = (*Impl)(nil)
- Import aliasing: stdlib io aliased as goio
- UK English in comments (colour not color, initialise not initialize)
- No fmt.Print* debug statements (use go-log)
- Test coverage gaps

Report findings with file:line references. Do not fix — only report.
`
	case "security":
		prompt = `## SANDBOX: You are restricted to this directory only. No absolute paths, no cd .., no editing outside src/.

Read CLAUDE.md for project context.
Review all Go files in src/ for security issues:
- Path traversal vulnerabilities
- Unvalidated input
- SQL injection (if applicable)
- Hardcoded credentials or tokens
- Unsafe type assertions
- Missing error checks
- Race conditions (shared state without mutex)
- Unsafe use of os/exec

Report findings with severity (critical/high/medium/low) and file:line references.
`
	case "coding":
		prompt = `Read PERSONA.md if it exists — adopt that identity and approach.
Read CLAUDE.md for project conventions and context.
Read TODO.md for your task.
Read PLAN.md if it exists — work through each phase in order.
Read CONTEXT.md for relevant knowledge from previous sessions.
Read CONSUMERS.md to understand breaking change risk.
Read RECENT.md for recent changes.

Work in the src/ directory. Follow the conventions in CLAUDE.md.

## SANDBOX BOUNDARY (HARD LIMIT)

You are restricted to the current directory and its subdirectories ONLY.
- Do NOT use absolute paths (e.g., /Users/..., /home/...)
- Do NOT navigate with cd .. or cd /
- Do NOT edit files outside this repository
- Do NOT access parent directories or other repos
- Any path in Edit/Write tool calls MUST be relative to the current directory
Violation of these rules will cause your work to be rejected.

## Workflow

If PLAN.md exists, you MUST work through it phase by phase:
1. Complete all tasks in the current phase
2. STOP and commit before moving on: type(scope): phase N - description
3. Only then start the next phase
4. If you are blocked or unsure, write BLOCKED.md explaining the question and stop
5. Do NOT skip phases or combine multiple phases into one commit

Each phase = one commit. This is not optional.

If no PLAN.md, complete TODO.md as a single unit of work.

## Commit Convention

Commit message format: type(scope): description
Co-Author: Co-Authored-By: Virgil <virgil@lethean.io>

Do NOT push. Commit only — a reviewer will verify and push.
`
	default:
		prompt = "SANDBOX: Restricted to this directory only. No absolute paths, no cd ..\n\nRead TODO.md and complete the task. Work in src/.\n"
	}

	coreio.Local.Write(filepath.Join(wsDir, "src", "PROMPT.md"), prompt)
}

// --- Plan template rendering ---

// writePlanFromTemplate loads a YAML plan template, substitutes variables,
// and writes PLAN.md into the workspace src/ directory.
func (s *PrepSubsystem) writePlanFromTemplate(templateSlug string, variables map[string]string, task string, wsDir string) {
	// Look for template in core/agent/prompts/templates/
	templatePath := filepath.Join(s.codePath, "core", "agent", "prompts", "templates", templateSlug+".yaml")
	data, err := coreio.Local.Read(templatePath)
	if err != nil {
		// Try .yml extension
		templatePath = filepath.Join(s.codePath, "core", "agent", "prompts", "templates", templateSlug+".yml")
		data, err = coreio.Local.Read(templatePath)
		if err != nil {
			return // Template not found, skip silently
		}
	}

	content := data

	// Substitute variables ({{variable_name}} → value)
	for key, value := range variables {
		content = strings.ReplaceAll(content, "{{"+key+"}}", value)
		content = strings.ReplaceAll(content, "{{ "+key+" }}", value)
	}

	// Parse the YAML to render as markdown
	var tmpl struct {
		Name        string   `yaml:"name"`
		Description string   `yaml:"description"`
		Guidelines  []string `yaml:"guidelines"`
		Phases      []struct {
			Name        string   `yaml:"name"`
			Description string   `yaml:"description"`
			Tasks       []any    `yaml:"tasks"`
		} `yaml:"phases"`
	}

	if err := yaml.Unmarshal([]byte(content), &tmpl); err != nil {
		return
	}

	// Render as PLAN.md
	var plan strings.Builder
	plan.WriteString("# Plan: " + tmpl.Name + "\n\n")
	if task != "" {
		plan.WriteString("**Task:** " + task + "\n\n")
	}
	if tmpl.Description != "" {
		plan.WriteString(tmpl.Description + "\n\n")
	}

	if len(tmpl.Guidelines) > 0 {
		plan.WriteString("## Guidelines\n\n")
		for _, g := range tmpl.Guidelines {
			plan.WriteString("- " + g + "\n")
		}
		plan.WriteString("\n")
	}

	for i, phase := range tmpl.Phases {
		plan.WriteString(fmt.Sprintf("## Phase %d: %s\n\n", i+1, phase.Name))
		if phase.Description != "" {
			plan.WriteString(phase.Description + "\n\n")
		}
		for _, task := range phase.Tasks {
			switch t := task.(type) {
			case string:
				plan.WriteString("- [ ] " + t + "\n")
			case map[string]any:
				if name, ok := t["name"].(string); ok {
					plan.WriteString("- [ ] " + name + "\n")
				}
			}
		}
		plan.WriteString("\n**Commit after completing this phase.**\n\n---\n\n")
	}

	coreio.Local.Write(filepath.Join(wsDir, "src", "PLAN.md"), plan.String())
}

// --- Helpers (unchanged) ---

func (s *PrepSubsystem) pullWiki(ctx context.Context, org, repo, wsDir string) int {
	if s.forgeToken == "" {
		return 0
	}

	url := fmt.Sprintf("%s/api/v1/repos/%s/%s/wiki/pages", s.forgeURL, org, repo)
	req, _ := http.NewRequestWithContext(ctx, "GET", url, nil)
	req.Header.Set("Authorization", "token "+s.forgeToken)

	resp, err := s.client.Do(req)
	if err != nil || resp.StatusCode != 200 {
		return 0
	}
	defer resp.Body.Close()

	var pages []struct {
		Title  string `json:"title"`
		SubURL string `json:"sub_url"`
	}
	json.NewDecoder(resp.Body).Decode(&pages)

	count := 0
	for _, page := range pages {
		subURL := page.SubURL
		if subURL == "" {
			subURL = page.Title
		}

		pageURL := fmt.Sprintf("%s/api/v1/repos/%s/%s/wiki/page/%s", s.forgeURL, org, repo, subURL)
		pageReq, _ := http.NewRequestWithContext(ctx, "GET", pageURL, nil)
		pageReq.Header.Set("Authorization", "token "+s.forgeToken)

		pageResp, err := s.client.Do(pageReq)
		if err != nil || pageResp.StatusCode != 200 {
			continue
		}

		var pageData struct {
			ContentBase64 string `json:"content_base64"`
		}
		json.NewDecoder(pageResp.Body).Decode(&pageData)
		pageResp.Body.Close()

		if pageData.ContentBase64 == "" {
			continue
		}

		content, _ := base64.StdEncoding.DecodeString(pageData.ContentBase64)
		filename := strings.Map(func(r rune) rune {
			if r >= 'a' && r <= 'z' || r >= 'A' && r <= 'Z' || r >= '0' && r <= '9' || r == '-' || r == '_' || r == '.' {
				return r
			}
			return '-'
		}, page.Title) + ".md"

		coreio.Local.Write(filepath.Join(wsDir, "src", "kb", filename), string(content))
		count++
	}

	return count
}

func (s *PrepSubsystem) copySpecs(wsDir string) int {
	specFiles := []string{"AGENT_CONTEXT.md", "TASK_PROTOCOL.md"}
	count := 0

	for _, file := range specFiles {
		src := filepath.Join(s.specsPath, file)
		if data, err := coreio.Local.Read(src); err == nil {
			coreio.Local.Write(filepath.Join(wsDir, "src", "specs", file), data)
			count++
		}
	}

	return count
}

func (s *PrepSubsystem) generateContext(ctx context.Context, repo, wsDir string) int {
	if s.brainKey == "" {
		return 0
	}

	body, _ := json.Marshal(map[string]any{
		"query":    "architecture conventions key interfaces for " + repo,
		"top_k":    10,
		"project":  repo,
		"agent_id": "cladius",
	})

	req, _ := http.NewRequestWithContext(ctx, "POST", s.brainURL+"/v1/brain/recall", strings.NewReader(string(body)))
	req.Header.Set("Content-Type", "application/json")
	req.Header.Set("Accept", "application/json")
	req.Header.Set("Authorization", "Bearer "+s.brainKey)

	resp, err := s.client.Do(req)
	if err != nil || resp.StatusCode != 200 {
		return 0
	}
	defer resp.Body.Close()

	respData, _ := io.ReadAll(resp.Body)
	var result struct {
		Memories []map[string]any `json:"memories"`
	}
	json.Unmarshal(respData, &result)

	var content strings.Builder
	content.WriteString("# Context — " + repo + "\n\n")
	content.WriteString("> Relevant knowledge from OpenBrain.\n\n")

	for i, mem := range result.Memories {
		memType, _ := mem["type"].(string)
		memContent, _ := mem["content"].(string)
		memProject, _ := mem["project"].(string)
		score, _ := mem["score"].(float64)
		content.WriteString(fmt.Sprintf("### %d. %s [%s] (score: %.3f)\n\n%s\n\n", i+1, memProject, memType, score, memContent))
	}

	coreio.Local.Write(filepath.Join(wsDir, "src", "CONTEXT.md"), content.String())
	return len(result.Memories)
}

func (s *PrepSubsystem) findConsumers(repo, wsDir string) int {
	goWorkPath := filepath.Join(s.codePath, "go.work")
	modulePath := "forge.lthn.ai/core/" + repo

	workData, err := coreio.Local.Read(goWorkPath)
	if err != nil {
		return 0
	}

	var consumers []string
	for _, line := range strings.Split(workData, "\n") {
		line = strings.TrimSpace(line)
		if !strings.HasPrefix(line, "./") {
			continue
		}
		dir := filepath.Join(s.codePath, strings.TrimPrefix(line, "./"))
		goMod := filepath.Join(dir, "go.mod")
		modData, err := coreio.Local.Read(goMod)
		if err != nil {
			continue
		}
		if strings.Contains(modData, modulePath) && !strings.HasPrefix(modData, "module "+modulePath) {
			consumers = append(consumers, filepath.Base(dir))
		}
	}

	if len(consumers) > 0 {
		content := "# Consumers of " + repo + "\n\n"
		content += "These modules import `" + modulePath + "`:\n\n"
		for _, c := range consumers {
			content += "- " + c + "\n"
		}
		content += fmt.Sprintf("\n**Breaking change risk: %d consumers.**\n", len(consumers))
		coreio.Local.Write(filepath.Join(wsDir, "src", "CONSUMERS.md"), content)
	}

	return len(consumers)
}

func (s *PrepSubsystem) gitLog(repoPath, wsDir string) int {
	cmd := exec.Command("git", "log", "--oneline", "-20")
	cmd.Dir = repoPath
	output, err := cmd.Output()
	if err != nil {
		return 0
	}

	lines := strings.Split(strings.TrimSpace(string(output)), "\n")
	if len(lines) > 0 && lines[0] != "" {
		content := "# Recent Changes\n\n```\n" + string(output) + "```\n"
		coreio.Local.Write(filepath.Join(wsDir, "src", "RECENT.md"), content)
	}

	return len(lines)
}

func (s *PrepSubsystem) generateTodo(ctx context.Context, org, repo string, issue int, wsDir string) {
	if s.forgeToken == "" {
		return
	}

	url := fmt.Sprintf("%s/api/v1/repos/%s/%s/issues/%d", s.forgeURL, org, repo, issue)
	req, _ := http.NewRequestWithContext(ctx, "GET", url, nil)
	req.Header.Set("Authorization", "token "+s.forgeToken)

	resp, err := s.client.Do(req)
	if err != nil || resp.StatusCode != 200 {
		return
	}
	defer resp.Body.Close()

	var issueData struct {
		Title string `json:"title"`
		Body  string `json:"body"`
	}
	json.NewDecoder(resp.Body).Decode(&issueData)

	content := fmt.Sprintf("# TASK: %s\n\n", issueData.Title)
	content += fmt.Sprintf("**Status:** ready\n")
	content += fmt.Sprintf("**Source:** %s/%s/%s/issues/%d\n", s.forgeURL, org, repo, issue)
	content += fmt.Sprintf("**Repo:** %s/%s\n\n---\n\n", org, repo)
	content += "## Objective\n\n" + issueData.Body + "\n"

	coreio.Local.Write(filepath.Join(wsDir, "src", "TODO.md"), content)
}