package main

import (
	"context"
	"errors"
	"log"

	"github.com/kami/maven/internal/mcp"
	"github.com/kami/maven/internal/phraser"
	"github.com/kami/maven/internal/router"
	"github.com/kami/maven/internal/tool"
)

// actionAct handles router.IntentAct: match a verb to an enabled tool, offer
// it to the ecosystems first, and run it behind the confirm gate and the
// allowlist. proposeGap and the confirm gate itself live in confirm.go.
func (h *reactiveHandler) actionAct(ctx context.Context, dec router.Decision) string {
	// tool executor: run the matched fn against the enabled allowlist.
	// HasFn=false ⇒ try the matcher (for LLM-routed acts where the verb
	// didn't go through the stage-0 act grammar).
	if !dec.Slots.HasFn && dec.Slots.Text != "" && h.matcher != nil {
		if fn, args, ok := h.matcher.Match(dec.Slots.Text); ok {
			dec.Slots.Fn, dec.Slots.Args, dec.Slots.HasFn = fn, args, true
		}
	}

	// The board is Maven's own store, so a spoken status change is answered here
	// and never offered to an ecosystem client (Vikunja #512). First, because
	// task_status is on no allowlist and no capability registry: reaching either
	// of them would answer a turn about his own task list with a gap.
	if dec.Slots.Fn == router.TaskStatusFn {
		return h.resolveTaskStatus(ctx, dec)
	}

	// Praxis ecosystem tools: intercept before the system command executor.
	if h.ecosystem != nil && h.ecosystem.praxis != nil && dec.Slots.HasFn {
		if reply := h.handlePraxisAct(ctx, dec); reply != "" {
			return reply
		}
	}

	// Hexis ecosystem action: if ecosystem is configured and we have a verb
	// + entity text, try to resolve the entity and execute via Hexis.
	if h.ecosystem != nil && h.ecosystem.hexis != nil && dec.Slots.Text != "" {
		if reply := h.handleHexisAct(ctx, dec); reply != "" {
			return reply
		}
	}

	// HasFn still false ⇒ no allowlist match: scaffold a 'proposed' tool
	// the user can enable on the authed surface ("earn the right to ask").
	if !dec.Slots.HasFn {
		return h.proposeGap(ctx, dec)
	}
	out, err := h.tools.Exec(ctx, dec.Slots.Fn, dec.Slots.Args, false)
	if err != nil {
		switch {
		case errors.Is(err, tool.ErrNeedsConfirm):
			// destructive: park it and ask. The next utterance answers.
			phrase := actPhrase(dec.Slots.Fn, dec.Slots.Args)
			h.park(dec.Slots.Fn, dec.Slots.Args, phrase)
			return phraser.A(phraser.ActConfirm, map[string]string{"name": phrase})
		case errors.Is(err, tool.ErrUnknownTarget):
			// The verb reached a tool and the tail did not reach a target, so
			// nothing ran. Saying which word she could not place is the whole
			// answer: he either renames it or gives the row an alias that
			// carries the target, and both are one turn away (V-634).
			word := ""
			var unknown *tool.UnknownTargetError
			if errors.As(err, &unknown) {
				word = unknown.Target
			}
			return phraser.A(phraser.ActUnknownTarget, map[string]string{"name": word})
		case errors.Is(err, tool.ErrNeedsAuthedSurface):
			// Irreversible (internal/tool/risk.go). A confirm turn would not
			// help: everything that proposed this act — the STT, the router,
			// the fuzzy allowlist match — is a guess, and a spoken "да" checks
			// none of it. She names the gap instead.
			return phraser.A(phraser.ActNeedsAuthedSurface, nil)
		case errors.Is(err, tool.ErrNotEnabled):
			return h.proposeGap(ctx, dec)
		case errors.Is(err, tool.ErrNotConnected), errors.Is(err, mcp.ErrNotConnected), errors.Is(err, mcp.ErrNoServer):
			// The row is enabled and the backend is gone. Drafting a proposal
			// for it (the ErrNotEnabled path) would be answering the wrong
			// question.
			return phraser.A(phraser.ActServerDown, nil)
		case errors.Is(err, mcp.ErrToolGone):
			return phraser.A(phraser.ActWithdrawn, nil)
		case errors.Is(err, mcp.ErrNeedsArgs):
			// An MCP tool that wants named arguments a spoken verb cannot
			// supply. Guessing them would be a wrong act, so she says so
			// instead — the tool is still runnable from the authed surface,
			// where a human types them.
			return phraser.A(phraser.ActNeedsArgs, nil)
		}
		log.Printf("voice: tool %s: %v", dec.Slots.Fn, err)
		if out != "" {
			return phraser.A(phraser.ActFailOut, map[string]string{"out": firstLine(out)})
		}
		return phraser.A(phraser.ActFail, nil)
	}
	if out != "" {
		return phraser.A(phraser.ActDoneOut, map[string]string{"out": firstLine(out)})
	}
	return phraser.A(phraser.ActDone, nil)
}