package council

import (
    "bytes"
    "crypto/sha256"
    "encoding/hex"
    "encoding/json"
    "errors"
    "fmt"
    "hash/fnv"
    "math/rand"
    "net/http"
    "strings"
    "sync"
    "time"

	"chorus/internal/persona"
)

// CouncilOpportunity represents a council formation opportunity from WHOOSH.
type CouncilOpportunity struct {
	CouncilID         string                 `json:"council_id"`
	ProjectName       string                 `json:"project_name"`
	Repository        string                 `json:"repository"`
	ProjectBrief      string                 `json:"project_brief"`
	CoreRoles         []CouncilRole          `json:"core_roles"`
	OptionalRoles     []CouncilRole          `json:"optional_roles"`
	UCXLAddress       string                 `json:"ucxl_address"`
	FormationDeadline time.Time              `json:"formation_deadline"`
	CreatedAt         time.Time              `json:"created_at"`
	Metadata          map[string]interface{} `json:"metadata"`
}

// CouncilRole represents a single role available within a council.
type CouncilRole struct {
	RoleName       string   `json:"role_name"`
	AgentName      string   `json:"agent_name"`
	Required       bool     `json:"required"`
	RequiredSkills []string `json:"required_skills"`
	Description    string   `json:"description"`
}

// RoleProfile mirrors WHOOSH role profile metadata included in claim responses.
type RoleProfile struct {
	RoleName          string   `json:"role_name"`
	DisplayName       string   `json:"display_name"`
	PromptKey         string   `json:"prompt_key"`
	PromptPack        string   `json:"prompt_pack"`
	Capabilities      []string `json:"capabilities"`
	BriefRoutingHint  string   `json:"brief_routing_hint"`
	DefaultBriefOwner bool     `json:"default_brief_owner"`
}

// CouncilBrief carries the high-level brief metadata for an activated council.
type CouncilBrief struct {
	CouncilID         string   `json:"council_id"`
	RoleName          string   `json:"role_name"`
	ProjectName       string   `json:"project_name"`
	Repository        string   `json:"repository"`
	Summary           string   `json:"summary"`
	BriefURL          string   `json:"brief_url"`
	IssueID           *int64   `json:"issue_id"`
	UCXLAddress       string   `json:"ucxl_address"`
	ExpectedArtifacts []string `json:"expected_artifacts"`
	HMMMTopic         string   `json:"hmmm_topic"`
}

// RoleAssignment keeps track of the agent's current council engagement.
type RoleAssignment struct {
	CouncilID   string
	RoleName    string
	UCXLAddress string
	AssignedAt  time.Time
	Profile     RoleProfile
	Brief       *CouncilBrief
	Persona     *persona.Persona
	PersonaHash string
}

var ErrRoleConflict = errors.New("council role already claimed")

const defaultModelProvider = "ollama"

// Manager handles council opportunity evaluation, persona preparation, and brief handoff.
type Manager struct {
	agentID      string
	agentName    string
	endpoint     string
	p2pAddr      string
	capabilities []string

	httpClient    *http.Client
	personaLoader *persona.Loader

	mu                sync.Mutex
	currentAssignment *RoleAssignment
}

// NewManager creates a new council manager.
func NewManager(agentID, agentName, endpoint, p2pAddr string, capabilities []string) *Manager {
	loader, err := persona.NewLoader()
	if err != nil {
		fmt.Printf("⚠️ Persona loader initialisation failed: %v\n", err)
	}

	return &Manager{
		agentID:       agentID,
		agentName:     agentName,
		endpoint:      endpoint,
		p2pAddr:       p2pAddr,
		capabilities:  capabilities,
		httpClient:    &http.Client{Timeout: 10 * time.Second},
		personaLoader: loader,
	}
}

// AgentID returns the agent's identifier.
func (m *Manager) AgentID() string {
	return m.agentID
}

// EvaluateOpportunity analyzes a council opportunity and decides whether to claim a role.
func (m *Manager) EvaluateOpportunity(opportunity *CouncilOpportunity, whooshEndpoint string) error {
	fmt.Printf("\n🤔 Evaluating council opportunity for: %s\n", opportunity.ProjectName)

	if current := m.currentAssignmentSnapshot(); current != nil {
		fmt.Printf("   ℹ️ Agent already assigned to council %s as %s; skipping new claims\n", current.CouncilID, current.RoleName)
		return nil
	}

	const maxAttempts = 10
	const retryDelay = 3 * time.Second

	var attemptedAtLeastOne bool

	for attempt := 1; attempt <= maxAttempts; attempt++ {
		assignment, attemptedCore, err := m.tryClaimRoles(opportunity.CoreRoles, opportunity, whooshEndpoint, "CORE")
		attemptedAtLeastOne = attemptedAtLeastOne || attemptedCore
		if assignment != nil {
			m.setCurrentAssignment(assignment)
			return nil
		}
		if err != nil && !errors.Is(err, ErrRoleConflict) {
			return err
		}

		assignment, attemptedOptional, err := m.tryClaimRoles(opportunity.OptionalRoles, opportunity, whooshEndpoint, "OPTIONAL")
		attemptedAtLeastOne = attemptedAtLeastOne || attemptedOptional
		if assignment != nil {
			m.setCurrentAssignment(assignment)
			return nil
		}
		if err != nil && !errors.Is(err, ErrRoleConflict) {
			return err
		}

		if !attemptedAtLeastOne {
			fmt.Printf("   ✗ No suitable roles found for this agent\n\n")
			return nil
		}

		fmt.Printf("   ↻ Attempt %d did not secure a council role; retrying in %s...\n", attempt, retryDelay)
		time.Sleep(retryDelay)
	}

	return fmt.Errorf("exhausted council role claim attempts for council %s", opportunity.CouncilID)
}

func (m *Manager) tryClaimRoles(roles []CouncilRole, opportunity *CouncilOpportunity, whooshEndpoint string, roleType string) (*RoleAssignment, bool, error) {
    var attempted bool

    // Shuffle roles deterministically per agent+council to reduce herd on the first role
    shuffled := append([]CouncilRole(nil), roles...)
    if len(shuffled) > 1 {
        h := fnv.New64a()
        _, _ = h.Write([]byte(m.agentID))
        _, _ = h.Write([]byte(opportunity.CouncilID))
        seed := int64(h.Sum64())
        r := rand.New(rand.NewSource(seed))
        r.Shuffle(len(shuffled), func(i, j int) { shuffled[i], shuffled[j] = shuffled[j], shuffled[i] })
    }

    for _, role := range shuffled {
        if !m.shouldClaimRole(role, opportunity) {
            continue
        }

		attempted = true
		fmt.Printf("   ✓ Attempting to claim %s role: %s (%s)\n", roleType, role.AgentName, role.RoleName)

		assignment, err := m.claimRole(opportunity, role, whooshEndpoint)
		if assignment != nil {
			return assignment, attempted, nil
		}

		if errors.Is(err, ErrRoleConflict) {
			fmt.Printf("   ⚠️ Role %s already claimed by another agent, trying next role...\n", role.RoleName)
			continue
		}

		if err != nil {
			return nil, attempted, err
		}
	}

	return nil, attempted, nil
}

func (m *Manager) shouldClaimRole(role CouncilRole, _ *CouncilOpportunity) bool {
	if m.hasActiveAssignment() {
		return false
	}
	// TODO: implement capability-based selection. For now, opportunistically claim any available role.
	return true
}

func (m *Manager) claimRole(opportunity *CouncilOpportunity, role CouncilRole, whooshEndpoint string) (*RoleAssignment, error) {
	claimURL := fmt.Sprintf("%s/api/v1/councils/%s/claims", strings.TrimRight(whooshEndpoint, "/"), opportunity.CouncilID)

	claim := map[string]interface{}{
		"agent_id":     m.agentID,
		"agent_name":   m.agentName,
		"role_name":    role.RoleName,
		"capabilities": m.capabilities,
		"confidence":   0.75, // TODO: calculate based on capability match quality.
		"reasoning":    fmt.Sprintf("Agent has capabilities matching role: %s", role.RoleName),
		"endpoint":     m.endpoint,
		"p2p_addr":     m.p2pAddr,
	}

	payload, err := json.Marshal(claim)
	if err != nil {
		return nil, fmt.Errorf("failed to marshal claim: %w", err)
	}

	req, err := http.NewRequest(http.MethodPost, claimURL, bytes.NewBuffer(payload))
	if err != nil {
		return nil, fmt.Errorf("failed to create claim request: %w", err)
	}
	req.Header.Set("Content-Type", "application/json")

	resp, err := m.httpClient.Do(req)
	if err != nil {
		return nil, fmt.Errorf("failed to send claim: %w", err)
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK && resp.StatusCode != http.StatusCreated {
		var errorResp map[string]interface{}
		_ = json.NewDecoder(resp.Body).Decode(&errorResp)

		if resp.StatusCode == http.StatusConflict {
			reason := "role already claimed"
			if msg, ok := errorResp["error"].(string); ok && msg != "" {
				reason = msg
			}
			return nil, fmt.Errorf("%w: %s", ErrRoleConflict, reason)
		}

		return nil, fmt.Errorf("claim rejected (status %d): %v", resp.StatusCode, errorResp)
	}

	var claimResp roleClaimResponse
	if err := json.NewDecoder(resp.Body).Decode(&claimResp); err != nil {
		return nil, fmt.Errorf("failed to decode claim response: %w", err)
	}

	assignment := &RoleAssignment{
		CouncilID:   opportunity.CouncilID,
		RoleName:    role.RoleName,
		UCXLAddress: claimResp.UCXLAddress,
		Profile:     claimResp.RoleProfile,
	}

	if t, err := time.Parse(time.RFC3339, claimResp.AssignedAt); err == nil {
		assignment.AssignedAt = t
	}

	if claimResp.CouncilBrief != nil {
		assignment.Brief = claimResp.CouncilBrief
	}

	fmt.Printf("\n✅ ROLE CLAIM ACCEPTED!\n")
	fmt.Printf("   Council ID: %s\n", opportunity.CouncilID)
	fmt.Printf("   Role: %s (%s)\n", role.AgentName, role.RoleName)
	fmt.Printf("   UCXL: %s\n", assignment.UCXLAddress)
	fmt.Printf("   Assigned At: %s\n", claimResp.AssignedAt)

	if err := m.preparePersonaAndAck(opportunity.CouncilID, role.RoleName, &assignment.Profile, claimResp.CouncilBrief, whooshEndpoint, assignment); err != nil {
		fmt.Printf("   ⚠️ Persona preparation encountered an issue: %v\n", err)
	}

	fmt.Printf("\n")
	return assignment, nil
}

func (m *Manager) preparePersonaAndAck(councilID, roleName string, profile *RoleProfile, brief *CouncilBrief, whooshEndpoint string, assignment *RoleAssignment) error {
	if m.personaLoader == nil {
		return m.sendPersonaAck(councilID, roleName, whooshEndpoint, nil, "", "failed", []string{"persona loader unavailable"})
	}

	promptKey := profile.PromptKey
	if promptKey == "" {
		promptKey = roleName
	}

	personaCapabilities := profile.Capabilities
	personaCapabilities = append([]string{}, personaCapabilities...)

	personaEntry, err := m.personaLoader.Compose(promptKey, profile.DisplayName, "", personaCapabilities)
	if err != nil {
		return m.sendPersonaAck(councilID, roleName, whooshEndpoint, nil, "", "failed", []string{err.Error()})
	}

	hash := sha256.Sum256([]byte(personaEntry.SystemPrompt))
	personaHash := hex.EncodeToString(hash[:])

	assignment.Persona = personaEntry
	assignment.PersonaHash = personaHash

	if err := m.sendPersonaAck(councilID, roleName, whooshEndpoint, personaEntry, personaHash, "loaded", nil); err != nil {
		return err
	}

	return nil
}

func (m *Manager) sendPersonaAck(councilID, roleName, whooshEndpoint string, personaEntry *persona.Persona, personaHash string, status string, errs []string) error {
	ackURL := fmt.Sprintf("%s/api/v1/councils/%s/roles/%s/personas", strings.TrimRight(whooshEndpoint, "/"), councilID, roleName)

	payload := map[string]interface{}{
		"agent_id":       m.agentID,
		"status":         status,
		"model_provider": defaultModelProvider,
		"capabilities":   m.capabilities,
		"metadata": map[string]interface{}{
			"endpoint":   m.endpoint,
			"p2p_addr":   m.p2pAddr,
			"agent_name": m.agentName,
		},
	}

	if personaEntry != nil {
		payload["system_prompt_hash"] = personaHash
		payload["model_name"] = personaEntry.Model
		if len(personaEntry.Capabilities) > 0 {
			payload["capabilities"] = personaEntry.Capabilities
		}
	}

	if len(errs) > 0 {
		payload["errors"] = errs
	}

	body, err := json.Marshal(payload)
	if err != nil {
		return fmt.Errorf("marshal persona ack: %w", err)
	}

	req, err := http.NewRequest(http.MethodPost, ackURL, bytes.NewBuffer(body))
	if err != nil {
		return fmt.Errorf("create persona ack request: %w", err)
	}
	req.Header.Set("Content-Type", "application/json")

	resp, err := m.httpClient.Do(req)
	if err != nil {
		return fmt.Errorf("send persona ack: %w", err)
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK && resp.StatusCode != http.StatusAccepted {
		return fmt.Errorf("persona ack rejected with status %d", resp.StatusCode)
	}

	fmt.Printf("   📫 Persona status '%s' acknowledged by WHOOSH\n", status)
	return nil
}

// HandleCouncilBrief records the design brief assigned to this agent once WHOOSH dispatches it.
func (m *Manager) HandleCouncilBrief(councilID, roleName string, brief *CouncilBrief) {
	if brief == nil {
		return
	}

	m.mu.Lock()
	defer m.mu.Unlock()

	if m.currentAssignment == nil {
		fmt.Printf("⚠️ Received council brief for %s (%s) but agent has no active assignment\n", councilID, roleName)
		return
	}

	if m.currentAssignment.CouncilID != councilID || !strings.EqualFold(m.currentAssignment.RoleName, roleName) {
		fmt.Printf("⚠️ Received council brief for %s (%s) but agent is assigned to %s (%s)\n", councilID, roleName, m.currentAssignment.CouncilID, m.currentAssignment.RoleName)
		return
	}

	brief.CouncilID = councilID
	brief.RoleName = roleName
	m.currentAssignment.Brief = brief

	fmt.Printf("📦 Design brief received for council %s (%s)\n", councilID, roleName)
	if brief.BriefURL != "" {
		fmt.Printf("   Brief URL: %s\n", brief.BriefURL)
	}
	if brief.Summary != "" {
		fmt.Printf("   Summary: %s\n", brief.Summary)
	}
	if len(brief.ExpectedArtifacts) > 0 {
		fmt.Printf("   Expected Artifacts: %v\n", brief.ExpectedArtifacts)
	}
	if brief.HMMMTopic != "" {
		fmt.Printf("   HMMM Topic: %s\n", brief.HMMMTopic)
	}
}

func (m *Manager) hasActiveAssignment() bool {
	m.mu.Lock()
	defer m.mu.Unlock()
	return m.currentAssignment != nil
}

func (m *Manager) setCurrentAssignment(assignment *RoleAssignment) {
	m.mu.Lock()
	defer m.mu.Unlock()
	m.currentAssignment = assignment
}

func (m *Manager) currentAssignmentSnapshot() *RoleAssignment {
	m.mu.Lock()
	defer m.mu.Unlock()
	return m.currentAssignment
}

// GetCurrentAssignment returns the current role assignment (public accessor)
func (m *Manager) GetCurrentAssignment() *RoleAssignment {
	return m.currentAssignmentSnapshot()
}

// roleClaimResponse mirrors WHOOSH role claim response payload.
type roleClaimResponse struct {
	Status        string        `json:"status"`
	CouncilID     string        `json:"council_id"`
	RoleName      string        `json:"role_name"`
	UCXLAddress   string        `json:"ucxl_address"`
	AssignedAt    string        `json:"assigned_at"`
	RoleProfile   RoleProfile   `json:"role_profile"`
	CouncilBrief  *CouncilBrief `json:"council_brief"`
	PersonaStatus string        `json:"persona_status"`
}