package agentloop

import (
	"context"
	"encoding/json"
	"errors"
	"fmt"

	"github.com/thepeterstone/claudomator/internal/agentchannel"
	"github.com/thepeterstone/claudomator/internal/provider"
	"github.com/thepeterstone/claudomator/internal/sandbox"
)

// agentToolSpecs returns the eight tools available to the loop: the four
// agent back-channel tools (mirroring the MCP tools ContainerRunner exposes)
// plus the four sandbox tools, as provider-neutral ToolSpecs. Ported verbatim
// (same names/descriptions/JSON schemas) from the former
// executor.agentToolDefs (internal/executor/localtools.go).
func agentToolSpecs() []provider.ToolSpec {
	strProp := func(desc string) map[string]any {
		return map[string]any{"type": "string", "description": desc}
	}
	return []provider.ToolSpec{
		{
			Name:        "ask_user",
			Description: "Ask the user a question when you genuinely need a decision to proceed. The task pauses until the user answers; do not call other tools after this.",
			ParametersJSONSchema: map[string]any{
				"type": "object",
				"properties": map[string]any{
					"question": strProp("the question to ask, phrased as a real question"),
					"options":  map[string]any{"type": "array", "items": map[string]any{"type": "string"}, "description": "optional suggested answer choices"},
				},
				"required": []string{"question"},
			},
		},
		{
			Name:        "report_summary",
			Description: "Record a concise 2-5 sentence summary of what you accomplished. Call this before finishing.",
			ParametersJSONSchema: map[string]any{
				"type":       "object",
				"properties": map[string]any{"summary": strProp("the summary text")},
				"required":   []string{"summary"},
			},
		},
		{
			Name:        "spawn_subtask",
			Description: "Create a child task to be executed separately. Use this to break large work into focused pieces.",
			ParametersJSONSchema: map[string]any{
				"type": "object",
				"properties": map[string]any{
					"name":           strProp("short descriptive name for the subtask"),
					"instructions":   strProp("complete instructions for the subtask agent"),
					"model":          strProp("optional model override"),
					"max_budget_usd": map[string]any{"type": "number", "description": "optional budget cap in USD"},
				},
				"required": []string{"name", "instructions"},
			},
		},
		{
			Name:        "record_progress",
			Description: "Record a short progress note that appears in the task timeline.",
			ParametersJSONSchema: map[string]any{
				"type":       "object",
				"properties": map[string]any{"message": strProp("a short progress note")},
				"required":   []string{"message"},
			},
		},
		{
			Name:        "read_file",
			Description: "Read the contents of a file in the sandbox working directory.",
			ParametersJSONSchema: map[string]any{
				"type":       "object",
				"properties": map[string]any{"path": strProp("path to the file, relative or absolute")},
				"required":   []string{"path"},
			},
		},
		{
			Name:        "write_file",
			Description: "Write or overwrite a file in the sandbox working directory.",
			ParametersJSONSchema: map[string]any{
				"type": "object",
				"properties": map[string]any{
					"path":    strProp("path to the file, relative or absolute"),
					"content": strProp("content to write"),
				},
				"required": []string{"path", "content"},
			},
		},
		{
			Name:        "run_bash",
			Description: "Run a shell command in the sandbox working directory. Returns exit code, stdout, and stderr.",
			ParametersJSONSchema: map[string]any{
				"type":       "object",
				"properties": map[string]any{"command": strProp("shell command to execute")},
				"required":   []string{"command"},
			},
		},
		{
			Name:        "glob",
			Description: "List files matching a glob pattern relative to the sandbox working directory.",
			ParametersJSONSchema: map[string]any{
				"type":       "object",
				"properties": map[string]any{"pattern": strProp("glob pattern, e.g. **/*.go")},
				"required":   []string{"pattern"},
			},
		},
	}
}

// dispatchTool invokes one model-requested tool. Back-channel tools
// (ask_user/report_summary/spawn_subtask/record_progress) go to l.Channel;
// sandbox tools (read_file/write_file/run_bash/glob) go to l.Sandbox. It
// returns the text to feed back to the model as the tool result, and a
// blocked flag set when ask_user could not be answered in-session (the run
// must stop and the task block). Ported from the former
// executor.dispatchAgentTool (internal/executor/localtools.go), preserving
// identical result-string formatting.
func (l *Loop) dispatchTool(ctx context.Context, name, argsJSON string) (result string, blocked bool, err error) {
	switch name {
	case "ask_user":
		var a struct {
			Question string   `json:"question"`
			Options  []string `json:"options"`
		}
		_ = json.Unmarshal([]byte(argsJSON), &a)
		q := map[string]any{"text": a.Question}
		if len(a.Options) > 0 {
			q["options"] = a.Options
		}
		payload, _ := json.Marshal(q)
		ans, askErr := l.Channel.AskUser(ctx, string(payload))
		if errors.Is(askErr, agentchannel.ErrAgentBlocked) {
			return "", true, nil
		}
		if askErr != nil {
			return "", false, askErr
		}
		return ans, false, nil

	case "report_summary":
		var a struct {
			Summary string `json:"summary"`
		}
		_ = json.Unmarshal([]byte(argsJSON), &a)
		if rsErr := l.Channel.ReportSummary(ctx, a.Summary); rsErr != nil {
			return "", false, rsErr
		}
		return "Summary recorded.", false, nil

	case "spawn_subtask":
		var a struct {
			Name         string  `json:"name"`
			Instructions string  `json:"instructions"`
			Model        string  `json:"model"`
			MaxBudgetUSD float64 `json:"max_budget_usd"`
		}
		_ = json.Unmarshal([]byte(argsJSON), &a)
		id, ssErr := l.Channel.SpawnSubtask(ctx, agentchannel.SubtaskSpec{
			Name:         a.Name,
			Instructions: a.Instructions,
			Model:        a.Model,
			MaxBudgetUSD: a.MaxBudgetUSD,
		})
		if ssErr != nil {
			return "", false, ssErr
		}
		return "Created subtask " + id, false, nil

	case "record_progress":
		var a struct {
			Message string `json:"message"`
		}
		_ = json.Unmarshal([]byte(argsJSON), &a)
		if rpErr := l.Channel.RecordProgress(ctx, a.Message); rpErr != nil {
			return "", false, rpErr
		}
		return "Noted.", false, nil

	case "read_file":
		var a struct {
			Path string `json:"path"`
		}
		_ = json.Unmarshal([]byte(argsJSON), &a)
		content, readErr := l.Sandbox.ReadFile(ctx, a.Path)
		if readErr != nil {
			return "", false, readErr
		}
		return content, false, nil

	case "write_file":
		var a struct {
			Path    string `json:"path"`
			Content string `json:"content"`
		}
		_ = json.Unmarshal([]byte(argsJSON), &a)
		if writeErr := l.Sandbox.WriteFile(ctx, a.Path, a.Content); writeErr != nil {
			// A guardrail rejection (sandbox.Guarded wrapping the real
			// Sandbox) is not a fatal execution error: feed the reason back
			// to the model as ordinary tool content so it can self-correct,
			// instead of aborting the whole run the way a genuine sandbox
			// failure (e.g. no working directory) does.
			var rej *sandbox.RejectionError
			if errors.As(writeErr, &rej) {
				return rej.Error(), false, nil
			}
			return "", false, writeErr
		}
		return "Written.", false, nil

	case "run_bash":
		var a struct {
			Command string `json:"command"`
		}
		_ = json.Unmarshal([]byte(argsJSON), &a)
		out, errOut, exitCode, runErr := l.Sandbox.RunBash(ctx, a.Command)
		if runErr != nil {
			var rej *sandbox.RejectionError
			if errors.As(runErr, &rej) {
				return rej.Error(), false, nil
			}
			return "", false, runErr
		}
		return fmt.Sprintf("exit_code: %d\nstdout:\n%s\nstderr:\n%s", exitCode, out, errOut), false, nil

	case "glob":
		var a struct {
			Pattern string `json:"pattern"`
		}
		_ = json.Unmarshal([]byte(argsJSON), &a)
		matches, globErr := l.Sandbox.Glob(ctx, a.Pattern)
		if globErr != nil {
			return "", false, globErr
		}
		out, _ := json.Marshal(matches)
		return string(out), false, nil

	default:
		return "", false, fmt.Errorf("unknown tool %q", name)
	}
}