import { Router } from "@oak/oak";
import { db } from "../config/database.ts";
import { authenticateToken, authorize, getCurrentUser } from "../middleware/auth.ts";
import { sanitizeInput } from "../middleware/security.ts";

const router = new Router();

// Standard Rate interface
interface StandardRate {
  id: number;
  sub_department_id: number | null;
  activity: string | null;
  rate: number;
  effective_date: Date;
  created_by: number;
  created_at: Date;
  sub_department_name?: string;
  department_name?: string;
  department_id?: number;
  created_by_name?: string;
}

// Get all standard rates (default rates for comparison)
router.get("/", authenticateToken, async (ctx) => {
  try {
    const currentUser = getCurrentUser(ctx);
    const params = ctx.request.url.searchParams;
    const departmentId = params.get("departmentId");
    const subDepartmentId = params.get("subDepartmentId");
    const activity = params.get("activity");
    
    let query = `
      SELECT sr.*, 
             sd.name as sub_department_name,
             d.name as department_name,
             d.id as department_id,
             u.name as created_by_name
      FROM standard_rates sr
      LEFT JOIN sub_departments sd ON sr.sub_department_id = sd.id
      LEFT JOIN departments d ON sd.department_id = d.id
      LEFT JOIN users u ON sr.created_by = u.id
      WHERE 1=1
    `;
    const queryParams: unknown[] = [];
    
    // Supervisors can only see rates for their department
    if (currentUser.role === "Supervisor") {
      query += " AND d.id = ?";
      queryParams.push(currentUser.departmentId);
    }
    
    if (departmentId) {
      query += " AND d.id = ?";
      queryParams.push(departmentId);
    }
    
    if (subDepartmentId) {
      query += " AND sr.sub_department_id = ?";
      queryParams.push(subDepartmentId);
    }
    
    if (activity) {
      query += " AND sr.activity = ?";
      queryParams.push(activity);
    }
    
    query += " ORDER BY sr.effective_date DESC, sr.created_at DESC";
    
    const rates = await db.query<StandardRate[]>(query, queryParams);
    ctx.response.body = rates;
  } catch (error) {
    console.error("Get standard rates error:", error);
    ctx.response.status = 500;
    ctx.response.body = { error: "Internal server error" };
  }
});

// Get all rates (contractor + standard) for SuperAdmin - all departments, sorted by date
router.get("/all-rates", authenticateToken, authorize("SuperAdmin"), async (ctx) => {
  try {
    const params = ctx.request.url.searchParams;
    const departmentId = params.get("departmentId");
    const startDate = params.get("startDate");
    const endDate = params.get("endDate");
    
    // Get contractor rates
    let contractorQuery = `
      SELECT 
        cr.id,
        'contractor' as rate_type,
        cr.contractor_id,
        u.name as contractor_name,
        cr.sub_department_id,
        sd.name as sub_department_name,
        d.id as department_id,
        d.name as department_name,
        cr.activity,
        cr.rate,
        cr.effective_date,
        cr.created_at,
        NULL as created_by,
        NULL as created_by_name
      FROM contractor_rates cr
      JOIN users u ON cr.contractor_id = u.id
      LEFT JOIN sub_departments sd ON cr.sub_department_id = sd.id
      LEFT JOIN departments d ON sd.department_id = d.id
      WHERE 1=1
    `;
    const contractorParams: unknown[] = [];
    
    if (departmentId) {
      contractorQuery += " AND d.id = ?";
      contractorParams.push(departmentId);
    }
    
    if (startDate) {
      contractorQuery += " AND cr.effective_date >= ?";
      contractorParams.push(startDate);
    }
    
    if (endDate) {
      contractorQuery += " AND cr.effective_date <= ?";
      contractorParams.push(endDate);
    }
    
    // Get standard rates
    let standardQuery = `
      SELECT 
        sr.id,
        'standard' as rate_type,
        NULL as contractor_id,
        NULL as contractor_name,
        sr.sub_department_id,
        sd.name as sub_department_name,
        d.id as department_id,
        d.name as department_name,
        sr.activity,
        sr.rate,
        sr.effective_date,
        sr.created_at,
        sr.created_by,
        u.name as created_by_name
      FROM standard_rates sr
      LEFT JOIN sub_departments sd ON sr.sub_department_id = sd.id
      LEFT JOIN departments d ON sd.department_id = d.id
      LEFT JOIN users u ON sr.created_by = u.id
      WHERE 1=1
    `;
    const standardParams: unknown[] = [];
    
    if (departmentId) {
      standardQuery += " AND d.id = ?";
      standardParams.push(departmentId);
    }
    
    if (startDate) {
      standardQuery += " AND sr.effective_date >= ?";
      standardParams.push(startDate);
    }
    
    if (endDate) {
      standardQuery += " AND sr.effective_date <= ?";
      standardParams.push(endDate);
    }
    
    const contractorRates = await db.query<any[]>(contractorQuery, contractorParams);
    const standardRates = await db.query<any[]>(standardQuery, standardParams);
    
    // Combine and sort by date
    const allRates = [...contractorRates, ...standardRates].sort((a, b) => {
      const dateA = new Date(a.effective_date).getTime();
      const dateB = new Date(b.effective_date).getTime();
      return dateB - dateA; // Descending order
    });
    
    ctx.response.body = {
      allRates,
      summary: {
        totalContractorRates: contractorRates.length,
        totalStandardRates: standardRates.length,
        totalRates: allRates.length,
      }
    };
  } catch (error) {
    console.error("Get all rates error:", error);
    ctx.response.status = 500;
    ctx.response.body = { error: "Internal server error" };
  }
});

// Compare contractor rates with standard rates
router.get("/compare", authenticateToken, authorize("Supervisor", "SuperAdmin"), async (ctx) => {
  try {
    const currentUser = getCurrentUser(ctx);
    const params = ctx.request.url.searchParams;
    const contractorId = params.get("contractorId");
    const subDepartmentId = params.get("subDepartmentId");
    
    let departmentFilter = "";
    const queryParams: unknown[] = [];
    
    if (currentUser.role === "Supervisor") {
      departmentFilter = " AND d.id = ?";
      queryParams.push(currentUser.departmentId);
    }
    
    // Get standard rates
    let standardQuery = `
      SELECT sr.*, 
             sd.name as sub_department_name,
             d.name as department_name,
             d.id as department_id
      FROM standard_rates sr
      LEFT JOIN sub_departments sd ON sr.sub_department_id = sd.id
      LEFT JOIN departments d ON sd.department_id = d.id
      WHERE 1=1 ${departmentFilter}
    `;
    
    if (subDepartmentId) {
      standardQuery += " AND sr.sub_department_id = ?";
      queryParams.push(subDepartmentId);
    }
    
    standardQuery += " ORDER BY sr.effective_date DESC";
    
    const standardRates = await db.query<StandardRate[]>(standardQuery, queryParams);
    
    // Get contractor rates for comparison
    let contractorQuery = `
      SELECT cr.*, 
             u.name as contractor_name,
             sd.name as sub_department_name,
             d.name as department_name,
             d.id as department_id
      FROM contractor_rates cr
      JOIN users u ON cr.contractor_id = u.id
      LEFT JOIN sub_departments sd ON cr.sub_department_id = sd.id
      LEFT JOIN departments d ON sd.department_id = d.id
      WHERE 1=1
    `;
    const contractorParams: unknown[] = [];
    
    if (currentUser.role === "Supervisor") {
      contractorQuery += " AND d.id = ?";
      contractorParams.push(currentUser.departmentId);
    }
    
    if (contractorId) {
      contractorQuery += " AND cr.contractor_id = ?";
      contractorParams.push(contractorId);
    }
    
    if (subDepartmentId) {
      contractorQuery += " AND cr.sub_department_id = ?";
      contractorParams.push(subDepartmentId);
    }
    
    contractorQuery += " ORDER BY cr.effective_date DESC";
    
    const contractorRates = await db.query<any[]>(contractorQuery, contractorParams);
    
    // Build comparison data
    const comparisons = contractorRates.map(cr => {
      // Find matching standard rate
      const matchingStandard = standardRates.find(sr => 
        sr.sub_department_id === cr.sub_department_id && 
        sr.activity === cr.activity
      );
      
      const standardRate = matchingStandard?.rate || 0;
      const contractorRate = cr.rate || 0;
      const difference = contractorRate - standardRate;
      const percentageDiff = standardRate > 0 ? ((difference / standardRate) * 100).toFixed(2) : null;
      
      return {
        ...cr,
        standard_rate: standardRate,
        difference,
        percentage_difference: percentageDiff,
        is_above_standard: difference > 0,
        is_below_standard: difference < 0,
      };
    });
    
    ctx.response.body = {
      standardRates,
      contractorRates,
      comparisons,
    };
  } catch (error) {
    console.error("Compare rates error:", error);
    ctx.response.status = 500;
    ctx.response.body = { error: "Internal server error" };
  }
});

// Create standard rate (Supervisor or SuperAdmin)
router.post("/", authenticateToken, authorize("Supervisor", "SuperAdmin"), async (ctx) => {
  try {
    const currentUser = getCurrentUser(ctx);
    const body = await ctx.request.body.json() as {
      subDepartmentId?: number;
      activity?: string;
      rate: number;
      effectiveDate: string;
    };
    const { subDepartmentId, activity, rate, effectiveDate } = body;
    
    if (!rate || !effectiveDate) {
      ctx.response.status = 400;
      ctx.response.body = { error: "Missing required fields (rate, effectiveDate)" };
      return;
    }
    
    // Verify sub-department belongs to supervisor's department if supervisor
    if (subDepartmentId && currentUser.role === "Supervisor") {
      const subDepts = await db.query<any[]>(
        "SELECT sd.* FROM sub_departments sd JOIN departments d ON sd.department_id = d.id WHERE sd.id = ? AND d.id = ?",
        [subDepartmentId, currentUser.departmentId]
      );
      
      if (subDepts.length === 0) {
        ctx.response.status = 403;
        ctx.response.body = { error: "Sub-department not in your department" };
        return;
      }
    }
    
    const sanitizedActivity = activity ? sanitizeInput(activity) : null;
    
    const result = await db.execute(
      "INSERT INTO standard_rates (sub_department_id, activity, rate, effective_date, created_by) VALUES (?, ?, ?, ?, ?)",
      [subDepartmentId || null, sanitizedActivity, rate, effectiveDate, currentUser.id]
    );
    
    const newRate = await db.query<StandardRate[]>(
      `SELECT sr.*, 
              sd.name as sub_department_name,
              d.name as department_name,
              u.name as created_by_name
       FROM standard_rates sr
       LEFT JOIN sub_departments sd ON sr.sub_department_id = sd.id
       LEFT JOIN departments d ON sd.department_id = d.id
       LEFT JOIN users u ON sr.created_by = u.id
       WHERE sr.id = ?`,
      [result.insertId]
    );
    
    ctx.response.status = 201;
    ctx.response.body = newRate[0];
  } catch (error) {
    console.error("Create standard rate error:", error);
    ctx.response.status = 500;
    ctx.response.body = { error: "Internal server error" };
  }
});

// Update standard rate
router.put("/:id", authenticateToken, authorize("Supervisor", "SuperAdmin"), async (ctx) => {
  try {
    const currentUser = getCurrentUser(ctx);
    const rateId = ctx.params.id;
    const body = await ctx.request.body.json() as { rate?: number; activity?: string; effectiveDate?: string };
    const { rate, activity, effectiveDate } = body;
    
    // Verify rate exists and user has access
    let query = `
      SELECT sr.*, d.id as department_id 
      FROM standard_rates sr
      LEFT JOIN sub_departments sd ON sr.sub_department_id = sd.id
      LEFT JOIN departments d ON sd.department_id = d.id
      WHERE sr.id = ?
    `;
    const params: unknown[] = [rateId];
    
    const existing = await db.query<any[]>(query, params);
    
    if (existing.length === 0) {
      ctx.response.status = 404;
      ctx.response.body = { error: "Standard rate not found" };
      return;
    }
    
    // Supervisors can only update rates in their department
    if (currentUser.role === "Supervisor" && existing[0].department_id !== currentUser.departmentId) {
      ctx.response.status = 403;
      ctx.response.body = { error: "Access denied - rate not in your department" };
      return;
    }
    
    const updates: string[] = [];
    const updateParams: unknown[] = [];
    
    if (rate !== undefined) {
      updates.push("rate = ?");
      updateParams.push(rate);
    }
    if (activity !== undefined) {
      updates.push("activity = ?");
      updateParams.push(sanitizeInput(activity));
    }
    if (effectiveDate !== undefined) {
      updates.push("effective_date = ?");
      updateParams.push(effectiveDate);
    }
    
    if (updates.length === 0) {
      ctx.response.status = 400;
      ctx.response.body = { error: "No fields to update" };
      return;
    }
    
    updateParams.push(rateId);
    
    await db.execute(
      `UPDATE standard_rates SET ${updates.join(", ")} WHERE id = ?`,
      updateParams
    );
    
    const updatedRate = await db.query<StandardRate[]>(
      `SELECT sr.*, 
              sd.name as sub_department_name,
              d.name as department_name,
              u.name as created_by_name
       FROM standard_rates sr
       LEFT JOIN sub_departments sd ON sr.sub_department_id = sd.id
       LEFT JOIN departments d ON sd.department_id = d.id
       LEFT JOIN users u ON sr.created_by = u.id
       WHERE sr.id = ?`,
      [rateId]
    );
    
    ctx.response.body = updatedRate[0];
  } catch (error) {
    console.error("Update standard rate error:", error);
    ctx.response.status = 500;
    ctx.response.body = { error: "Internal server error" };
  }
});

// Delete standard rate
router.delete("/:id", authenticateToken, authorize("Supervisor", "SuperAdmin"), async (ctx) => {
  try {
    const currentUser = getCurrentUser(ctx);
    const rateId = ctx.params.id;
    
    // Verify rate exists and user has access
    const existing = await db.query<any[]>(
      `SELECT sr.*, d.id as department_id 
       FROM standard_rates sr
       LEFT JOIN sub_departments sd ON sr.sub_department_id = sd.id
       LEFT JOIN departments d ON sd.department_id = d.id
       WHERE sr.id = ?`,
      [rateId]
    );
    
    if (existing.length === 0) {
      ctx.response.status = 404;
      ctx.response.body = { error: "Standard rate not found" };
      return;
    }
    
    // Supervisors can only delete rates in their department
    if (currentUser.role === "Supervisor" && existing[0].department_id !== currentUser.departmentId) {
      ctx.response.status = 403;
      ctx.response.body = { error: "Access denied - rate not in your department" };
      return;
    }
    
    await db.execute("DELETE FROM standard_rates WHERE id = ?", [rateId]);
    ctx.response.body = { message: "Standard rate deleted successfully" };
  } catch (error) {
    console.error("Delete standard rate error:", error);
    ctx.response.status = 500;
    ctx.response.body = { error: "Internal server error" };
  }
});

export default router;