package intentflow

import (
	"fmt"

	"chat-agent-system/internal/intent"
)

const PolicyVersion = "batch-action-policy.v1"

// ActionBatchPolicy is the intentflow-owned batch row. It must not copy
// Risk, RequiredSlots, CapabilityKey, or AllowedStates from ActionRegistry.
type ActionBatchPolicy struct {
	ActionKey            string
	RequiresBatchConfirm bool
	OpenFromTier         PlanTier
	AllowedModes         []ExecutionMode
	RejectPlan           bool
}

// BatchActionPolicy is the versioned fail-closed matrix keyed by ActionSpec.Key.
type BatchActionPolicy struct {
	Version string
	byKey   map[string]ActionBatchPolicy
}

func DefaultBatchActionPolicy() *BatchActionPolicy {
	p, err := NewBatchActionPolicy(defaultBatchRows(), intent.DefaultRegistry())
	if err != nil {
		panic(err)
	}
	return p
}

func NewBatchActionPolicy(rows []ActionBatchPolicy, registry *intent.ActionRegistry) (*BatchActionPolicy, error) {
	if registry == nil {
		return nil, fmt.Errorf("intentflow: action registry is required")
	}
	byKey := make(map[string]ActionBatchPolicy, len(rows))
	for _, row := range rows {
		if row.ActionKey == "" {
			return nil, fmt.Errorf("intentflow: empty policy action key")
		}
		if _, exists := byKey[row.ActionKey]; exists {
			return nil, fmt.Errorf("intentflow: duplicate policy key %q", row.ActionKey)
		}
		if _, ok := registry.Get(row.ActionKey); !ok {
			return nil, fmt.Errorf("intentflow: unknown policy action key %q", row.ActionKey)
		}
		byKey[row.ActionKey] = row
	}
	for _, spec := range registry.All() {
		if spec == nil {
			continue
		}
		if _, ok := byKey[spec.Key]; !ok {
			return nil, fmt.Errorf("intentflow: action %q missing batch policy", spec.Key)
		}
	}
	return &BatchActionPolicy{Version: PolicyVersion, byKey: byKey}, nil
}

func (p *BatchActionPolicy) Lookup(key string) (ActionBatchPolicy, error) {
	if p == nil {
		return ActionBatchPolicy{}, fmt.Errorf("intentflow: policy is nil")
	}
	row, ok := p.byKey[key]
	if !ok {
		return ActionBatchPolicy{}, fmt.Errorf("intentflow: unknown action key %q", key)
	}
	return row, nil
}

func (p *BatchActionPolicy) RequiresBatchConfirm(key string) bool {
	row, err := p.Lookup(key)
	if err != nil {
		return true
	}
	return row.RequiresBatchConfirm || row.RejectPlan
}

func defaultBatchRows() []ActionBatchPolicy {
	autoRead := []string{
		"regulation.query",
		"case.query",
		"permission.query",
		"document.reject_reason.query",
		"workflow.status.query",
		"document.status.query",
		"run.status.query",
		"project.advisory",
		"conversation.help",
	}
	confirmGenerate := []string{"task.run", "task.run.adhoc"}
	rows := make([]ActionBatchPolicy, 0, len(intent.DefaultRegistry().All()))
	seen := map[string]struct{}{}
	add := func(row ActionBatchPolicy) {
		rows = append(rows, row)
		seen[row.ActionKey] = struct{}{}
	}
	for _, key := range autoRead {
		add(ActionBatchPolicy{
			ActionKey:            key,
			RequiresBatchConfirm: false,
			OpenFromTier:         TierAutoRead,
			AllowedModes:         []ExecutionMode{ModeLive, ModeValidatedOnly},
		})
	}
	for _, key := range confirmGenerate {
		add(ActionBatchPolicy{
			ActionKey:            key,
			RequiresBatchConfirm: true,
			OpenFromTier:         TierConfirm,
			AllowedModes:         []ExecutionMode{ModeValidatedOnly, ModeLive},
		})
	}
	for _, key := range []string{
		"project.fact.supplement",
		"document.claim",
		"document.review.submit",
		"workflow.run",
		"run.resume",
		// P8 逐键放量：confirm 档即可进入计划（真实执行仍受 per-key LIVE flag 限制；
		// flag 未开时 Owner 落 dry-run validated_only）。
		"document.review.approve",
		"document.review.reject",
		"document.final.approve",
		"document.final.reject",
		"document.proposal.decide",
		"workflow.switch",
		"run.restart",
	} {
		add(ActionBatchPolicy{
			ActionKey:            key,
			RequiresBatchConfirm: true,
			OpenFromTier:         TierConfirm,
			AllowedModes:         []ExecutionMode{ModeValidatedOnly, ModeLive},
		})
	}
	add(ActionBatchPolicy{
		ActionKey:    "security.forbidden",
		RejectPlan:   true,
		OpenFromTier: TierFull,
	})
	for _, spec := range intent.DefaultRegistry().All() {
		if spec == nil {
			continue
		}
		if _, ok := seen[spec.Key]; ok {
			continue
		}
		add(ActionBatchPolicy{
			ActionKey:            spec.Key,
			RequiresBatchConfirm: true,
			OpenFromTier:         TierFull,
			AllowedModes:         []ExecutionMode{ModeValidatedOnly},
		})
	}
	return rows
}