package handler

import (
	"encoding/json"
	"fmt"
	"net/http"
	"strings"
	"time"
)

func (h *Handler) handleCreateStatement(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodPost {
		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
		return
	}
	profile := getProfile(r.Context())

	dealID := r.FormValue("deal_id")
	title := strings.TrimSpace(r.FormValue("title"))
	body := strings.TrimSpace(r.FormValue("body"))

	if dealID == "" || title == "" || body == "" {
		http.Error(w, "deal_id, title, and body are required", 400)
		return
	}

	respID := generateID("resp")
	_, err := h.db.Exec(
		`INSERT INTO responses (id, deal_id, type, title, body, extraction_status, created_by) VALUES (?, ?, 'statement', ?, ?, 'pending', ?)`,
		respID, dealID, title, body, profile.ID)
	if err != nil {
		http.Error(w, fmt.Sprintf("Error creating statement: %v", err), 500)
		return
	}

	// Enqueue for chunking + embedding + matching
	if h.extractor != nil {
		h.enqueueExtraction(respID, "", dealID)
	}

	http.Redirect(w, r, "/deals/"+dealID+"?tab=requests", http.StatusSeeOther)
}

func (h *Handler) handleConfirmLink(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodPost {
		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
		return
	}
	profile := getProfile(r.Context())

	requestID := r.FormValue("request_id")
	responseID := r.FormValue("response_id")
	chunkID := r.FormValue("chunk_id")

	if requestID == "" || responseID == "" || chunkID == "" {
		http.Error(w, "Missing fields", 400)
		return
	}

	_, err := h.db.Exec(
		"UPDATE request_links SET confirmed = 1, confirmed_by = ?, confirmed_at = ? WHERE request_id = ? AND response_id = ? AND chunk_id = ?",
		profile.ID, time.Now().UTC().Format("2006-01-02 15:04:05"), requestID, responseID, chunkID)
	if err != nil {
		http.Error(w, "Error confirming link", 500)
		return
	}

	// Update request status to answered if not already
	h.db.Exec("UPDATE diligence_requests SET status = 'answered' WHERE id = ? AND status != 'answered'", requestID)

	w.Header().Set("Content-Type", "text/html")
	w.Write([]byte(`<span class="text-xs text-green-400 font-medium">Confirmed</span>`))
}

func (h *Handler) handleRejectLink(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodPost {
		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
		return
	}

	requestID := r.FormValue("request_id")
	responseID := r.FormValue("response_id")
	chunkID := r.FormValue("chunk_id")

	if requestID == "" || responseID == "" || chunkID == "" {
		http.Error(w, "Missing fields", 400)
		return
	}

	h.db.Exec("DELETE FROM request_links WHERE request_id = ? AND response_id = ? AND chunk_id = ?",
		requestID, responseID, chunkID)

	w.Header().Set("Content-Type", "text/html")
	w.Write([]byte(`<span class="text-xs text-gray-500 font-medium">Rejected</span>`))
}

func (h *Handler) handlePendingLinks(w http.ResponseWriter, r *http.Request) {
	dealID := strings.TrimPrefix(r.URL.Path, "/deals/responses/pending/")
	if dealID == "" {
		http.Error(w, "Missing deal ID", 400)
		return
	}

	rows, err := h.db.Query(`
		SELECT rl.request_id, rl.response_id, rl.chunk_id, rl.confidence,
			   dr.description, r.title, r.type
		FROM request_links rl
		JOIN diligence_requests dr ON rl.request_id = dr.id
		JOIN responses r ON rl.response_id = r.id
		WHERE dr.deal_id = ? AND rl.confirmed = 0 AND rl.auto_linked = 1
		ORDER BY rl.confidence DESC
	`, dealID)
	if err != nil {
		http.Error(w, "Error loading pending links", 500)
		return
	}
	defer rows.Close()

	type pendingLink struct {
		RequestID   string  `json:"request_id"`
		ResponseID  string  `json:"response_id"`
		ChunkID     string  `json:"chunk_id"`
		Confidence  float64 `json:"confidence"`
		RequestDesc string  `json:"request_desc"`
		ResponseTitle string `json:"response_title"`
		ResponseType string  `json:"response_type"`
	}

	var links []pendingLink
	for rows.Next() {
		var l pendingLink
		rows.Scan(&l.RequestID, &l.ResponseID, &l.ChunkID, &l.Confidence,
			&l.RequestDesc, &l.ResponseTitle, &l.ResponseType)
		links = append(links, l)
	}

	if links == nil {
		links = []pendingLink{}
	}
	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(links)
}

func (h *Handler) handleSaveAssignmentRules(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodPost {
		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
		return
	}

	dealID := r.FormValue("deal_id")
	rulesJSON := r.FormValue("rules")

	if dealID == "" {
		http.Error(w, "Missing deal_id", 400)
		return
	}

	type ruleInput struct {
		Keyword    string `json:"keyword"`
		AssigneeID string `json:"assignee_id"`
	}
	var rules []ruleInput
	if err := json.Unmarshal([]byte(rulesJSON), &rules); err != nil {
		http.Error(w, "Invalid rules JSON", 400)
		return
	}

	// Delete existing rules and insert new set
	h.db.Exec("DELETE FROM assignment_rules WHERE deal_id = ?", dealID)
	for _, rule := range rules {
		if rule.Keyword == "" || rule.AssigneeID == "" {
			continue
		}
		id := generateID("rule")
		h.db.Exec("INSERT INTO assignment_rules (id, deal_id, keyword, assignee_id) VALUES (?, ?, ?, ?)",
			id, dealID, rule.Keyword, rule.AssigneeID)
	}

	// Re-run auto-assignment
	h.autoAssignByRules(dealID)

	http.Redirect(w, r, "/deals/"+dealID+"?tab=requests", http.StatusSeeOther)
}

func (h *Handler) handleGetAssignmentRules(w http.ResponseWriter, r *http.Request) {
	dealID := strings.TrimPrefix(r.URL.Path, "/deals/assignment-rules/")
	if dealID == "" {
		http.Error(w, "Missing deal ID", 400)
		return
	}

	rows, err := h.db.Query(`
		SELECT ar.id, ar.keyword, ar.assignee_id, COALESCE(p.full_name, ar.assignee_id)
		FROM assignment_rules ar
		LEFT JOIN profiles p ON ar.assignee_id = p.id
		WHERE ar.deal_id = ?
		ORDER BY ar.keyword
	`, dealID)
	if err != nil {
		http.Error(w, "Error loading rules", 500)
		return
	}
	defer rows.Close()

	type ruleOut struct {
		ID           string `json:"id"`
		Keyword      string `json:"keyword"`
		AssigneeID   string `json:"assignee_id"`
		AssigneeName string `json:"assignee_name"`
	}
	var rules []ruleOut
	for rows.Next() {
		var r ruleOut
		rows.Scan(&r.ID, &r.Keyword, &r.AssigneeID, &r.AssigneeName)
		rules = append(rules, r)
	}
	if rules == nil {
		rules = []ruleOut{}
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(rules)
}

// autoAssignByRules assigns unassigned requests based on keyword→assignee rules.
func (h *Handler) autoAssignByRules(dealID string) {
	// Load rules
	ruleRows, err := h.db.Query("SELECT keyword, assignee_id FROM assignment_rules WHERE deal_id = ?", dealID)
	if err != nil {
		return
	}
	defer ruleRows.Close()

	type rule struct {
		keyword, assigneeID string
	}
	var rules []rule
	for ruleRows.Next() {
		var r rule
		ruleRows.Scan(&r.keyword, &r.assigneeID)
		rules = append(rules, r)
	}

	if len(rules) == 0 {
		return
	}

	// Load unassigned requests
	reqRows, err := h.db.Query("SELECT id, section, description FROM diligence_requests WHERE deal_id = ? AND (assignee_id = '' OR assignee_id IS NULL)", dealID)
	if err != nil {
		return
	}
	defer reqRows.Close()

	type reqInfo struct {
		id, section, desc string
	}
	var reqs []reqInfo
	for reqRows.Next() {
		var r reqInfo
		reqRows.Scan(&r.id, &r.section, &r.desc)
		reqs = append(reqs, r)
	}

	for _, req := range reqs {
		text := strings.ToLower(req.section + " " + req.desc)
		for _, rule := range rules {
			if strings.Contains(text, strings.ToLower(rule.keyword)) {
				h.db.Exec("UPDATE diligence_requests SET assignee_id = ? WHERE id = ?", rule.assigneeID, req.id)
				break
			}
		}
	}
}