"use client";

import React, { useState, useEffect } from 'react';
import { motion } from 'framer-motion';
import { Card, CardContent, CardDescription, CardHeader, CardTitle } from '@/components/ui/card';
import { Select, SelectContent, SelectItem, SelectTrigger, SelectValue } from '@/components/ui/select';
import { Badge } from '@/components/ui/badge';
import { Button } from '@/components/ui/button';
import { 
  Brain, 
  Zap, 
  Bot, 
  AlertCircle, 
  CheckCircle, 
  Settings2, 
  RefreshCw,
  Save,
  RotateCcw,
  Loader2
} from 'lucide-react';
import { useLLMConfigs, useLLMPreferences } from '@/hooks/use-llm-configs';
import { Alert, AlertDescription } from '@/components/ui/alert';
import { toast } from 'sonner';

const ROLE_DESCRIPTIONS = {
  long_context: {
    icon: Brain,
    title: 'Long Context LLM',
    description: 'Handles complex tasks requiring extensive context understanding and reasoning',
    color: 'bg-blue-100 text-blue-800 border-blue-200',
    examples: 'Document analysis, research synthesis, complex Q&A',
    characteristics: ['Large context window', 'Deep reasoning', 'Complex analysis']
  },
  fast: {
    icon: Zap,
    title: 'Fast LLM',
    description: 'Optimized for quick responses and real-time interactions',
    color: 'bg-green-100 text-green-800 border-green-200',
    examples: 'Quick searches, simple questions, instant responses',
    characteristics: ['Low latency', 'Quick responses', 'Real-time chat']
  },
  strategic: {
    icon: Bot,
    title: 'Strategic LLM',
    description: 'Advanced reasoning for planning and strategic decision making',
    color: 'bg-purple-100 text-purple-800 border-purple-200',
    examples: 'Planning workflows, strategic analysis, complex problem solving',
    characteristics: ['Strategic thinking', 'Long-term planning', 'Complex reasoning']
  }
};

export function LLMRoleManager() {
  const { llmConfigs, loading: configsLoading, error: configsError, refreshConfigs } = useLLMConfigs();
  const { preferences, loading: preferencesLoading, error: preferencesError, updatePreferences, refreshPreferences } = useLLMPreferences();
  
  const [assignments, setAssignments] = useState({
    long_context_llm_id: preferences.long_context_llm_id || '',
    fast_llm_id: preferences.fast_llm_id || '',
    strategic_llm_id: preferences.strategic_llm_id || ''
  });

  const [hasChanges, setHasChanges] = useState(false);
  const [isSaving, setIsSaving] = useState(false);

  useEffect(() => {
    const newAssignments = {
      long_context_llm_id: preferences.long_context_llm_id || '',
      fast_llm_id: preferences.fast_llm_id || '',
      strategic_llm_id: preferences.strategic_llm_id || ''
    };
    setAssignments(newAssignments);
    setHasChanges(false);
  }, [preferences]);

  const handleRoleAssignment = (role: string, configId: string) => {
    const newAssignments = {
      ...assignments,
      [role]: configId === 'unassigned' ? '' : parseInt(configId)
    };
    
    setAssignments(newAssignments);
    
    // Check if there are changes compared to current preferences
    const currentPrefs = {
      long_context_llm_id: preferences.long_context_llm_id || '',
      fast_llm_id: preferences.fast_llm_id || '',
      strategic_llm_id: preferences.strategic_llm_id || ''
    };
    
    const hasChangesNow = Object.keys(newAssignments).some(
      key => newAssignments[key as keyof typeof newAssignments] !== currentPrefs[key as keyof typeof currentPrefs]
    );
    
    setHasChanges(hasChangesNow);
  };

  const handleSave = async () => {
    setIsSaving(true);
    
    const numericAssignments = {
      long_context_llm_id: typeof assignments.long_context_llm_id === 'string' 
        ? (assignments.long_context_llm_id ? parseInt(assignments.long_context_llm_id) : undefined)
        : assignments.long_context_llm_id,
      fast_llm_id: typeof assignments.fast_llm_id === 'string' 
        ? (assignments.fast_llm_id ? parseInt(assignments.fast_llm_id) : undefined)
        : assignments.fast_llm_id,
      strategic_llm_id: typeof assignments.strategic_llm_id === 'string' 
        ? (assignments.strategic_llm_id ? parseInt(assignments.strategic_llm_id) : undefined)
        : assignments.strategic_llm_id,
    };
    
    const success = await updatePreferences(numericAssignments);
    
    if (success) {
      setHasChanges(false);
      toast.success('LLM role assignments saved successfully!');
    }
    
    setIsSaving(false);
  };

  const handleReset = () => {
    setAssignments({
      long_context_llm_id: preferences.long_context_llm_id || '',
      fast_llm_id: preferences.fast_llm_id || '',
      strategic_llm_id: preferences.strategic_llm_id || ''
    });
    setHasChanges(false);
  };

  const isAssignmentComplete = assignments.long_context_llm_id && assignments.fast_llm_id && assignments.strategic_llm_id;
  const assignedConfigIds = Object.values(assignments).filter(id => id !== '');
  const availableConfigs = llmConfigs.filter(config => config.id && config.id.toString().trim() !== '');
  
  const isLoading = configsLoading || preferencesLoading;
  const hasError = configsError || preferencesError;

  return (
    <div className="space-y-6">
      {/* Header */}
      <div className="flex flex-col space-y-4 lg:flex-row lg:items-center lg:justify-between lg:space-y-0">
        <div className="space-y-1">
          <div className="flex items-center space-x-3">
            <div className="flex h-10 w-10 items-center justify-center rounded-lg bg-purple-500/10">
              <Settings2 className="h-5 w-5 text-purple-600" />
            </div>
            <div>
              <h2 className="text-2xl font-bold tracking-tight">LLM Role Management</h2>
              <p className="text-muted-foreground">
                Assign your LLM configurations to specific roles for different purposes.
              </p>
            </div>
          </div>
        </div>
        <div className="flex flex-wrap gap-2">
          <Button
            variant="outline"
            size="sm"
            onClick={refreshConfigs}
            disabled={isLoading}
            className="flex items-center gap-2"
          >
            <RefreshCw className={`h-4 w-4 ${configsLoading ? 'animate-spin' : ''}`} />
            <span className="hidden sm:inline">Refresh Configs</span>
            <span className="sm:hidden">Configs</span>
          </Button>
          <Button
            variant="outline"
            size="sm"
            onClick={refreshPreferences}
            disabled={isLoading}
            className="flex items-center gap-2"
          >
            <RefreshCw className={`h-4 w-4 ${preferencesLoading ? 'animate-spin' : ''}`} />
            <span className="hidden sm:inline">Refresh Preferences</span>
            <span className="sm:hidden">Prefs</span>
          </Button>
        </div>
      </div>

      {/* Error Alert */}
      {hasError && (
        <Alert variant="destructive">
          <AlertCircle className="h-4 w-4" />
          <AlertDescription>
            {configsError || preferencesError}
          </AlertDescription>
        </Alert>
      )}

      {/* Loading State */}
      {isLoading && (
        <Card>
          <CardContent className="flex items-center justify-center py-12">
            <div className="flex items-center gap-2 text-muted-foreground">
              <Loader2 className="w-5 h-5 animate-spin" />
              <span>
                {configsLoading && preferencesLoading ? 'Loading configurations and preferences...' :
                 configsLoading ? 'Loading configurations...' :
                 'Loading preferences...'}
              </span>
            </div>
          </CardContent>
        </Card>
      )}

      {/* Stats Overview */}
      {!isLoading && !hasError && (
        <div className="grid gap-4 sm:grid-cols-2 lg:grid-cols-4">
          <Card className="border-l-4 border-l-blue-500">
            <CardContent className="p-6">
              <div className="flex items-center justify-between space-x-4">
                <div className="space-y-1">
                  <p className="text-3xl font-bold tracking-tight">{availableConfigs.length}</p>
                  <p className="text-sm font-medium text-muted-foreground">Available Models</p>
                </div>
                <div className="flex h-12 w-12 items-center justify-center rounded-lg bg-blue-500/10">
                  <Bot className="h-6 w-6 text-blue-600" />
                </div>
              </div>
            </CardContent>
          </Card>
          
          <Card className="border-l-4 border-l-purple-500">
            <CardContent className="p-6">
              <div className="flex items-center justify-between space-x-4">
                <div className="space-y-1">
                  <p className="text-3xl font-bold tracking-tight">{assignedConfigIds.length}</p>
                  <p className="text-sm font-medium text-muted-foreground">Assigned Roles</p>
                </div>
                <div className="flex h-12 w-12 items-center justify-center rounded-lg bg-purple-500/10">
                  <CheckCircle className="h-6 w-6 text-purple-600" />
                </div>
              </div>
            </CardContent>
          </Card>

          <Card className={`border-l-4 ${
            isAssignmentComplete ? 'border-l-green-500' : 'border-l-yellow-500'
          }`}>
            <CardContent className="p-6">
              <div className="flex items-center justify-between space-x-4">
                <div className="space-y-1">
                  <p className="text-3xl font-bold tracking-tight">
                    {Math.round((assignedConfigIds.length / 3) * 100)}%
                  </p>
                  <p className="text-sm font-medium text-muted-foreground">Completion</p>
                </div>
                <div className={`flex h-12 w-12 items-center justify-center rounded-lg ${
                  isAssignmentComplete ? 'bg-green-500/10' : 'bg-yellow-500/10'
                }`}>
                  {isAssignmentComplete ? (
                    <CheckCircle className="h-6 w-6 text-green-600" />
                  ) : (
                    <AlertCircle className="h-6 w-6 text-yellow-600" />
                  )}
                </div>
              </div>
            </CardContent>
          </Card>

          <Card className={`border-l-4 ${
            isAssignmentComplete ? 'border-l-emerald-500' : 'border-l-orange-500'
          }`}>
            <CardContent className="p-6">
              <div className="flex items-center justify-between space-x-4">
                <div className="space-y-1">
                  <p className={`text-3xl font-bold tracking-tight ${
                    isAssignmentComplete ? 'text-emerald-600' : 'text-orange-600'
                  }`}>
                    {isAssignmentComplete ? 'Ready' : 'Setup'}
                  </p>
                  <p className="text-sm font-medium text-muted-foreground">Status</p>
                </div>
                <div className={`flex h-12 w-12 items-center justify-center rounded-lg ${
                  isAssignmentComplete ? 'bg-emerald-500/10' : 'bg-orange-500/10'
                }`}>
                  {isAssignmentComplete ? (
                    <CheckCircle className="h-6 w-6 text-emerald-600" />
                  ) : (
                    <RefreshCw className="h-6 w-6 text-orange-600" />
                  )}
                </div>
              </div>
            </CardContent>
          </Card>
        </div>
      )}

      {/* Info Alert */}
      {!isLoading && !hasError && (
        <div className="space-y-6">
        {availableConfigs.length === 0 ? (
        <Alert variant="destructive">
          <AlertCircle className="h-4 w-4" />
          <AlertDescription>
            No LLM configurations found. Please add at least one LLM provider in the Model Configs tab before assigning roles.
          </AlertDescription>
        </Alert>
      ) : !isAssignmentComplete ? (
        <Alert>
          <AlertCircle className="h-4 w-4" />
          <AlertDescription>
            Complete all role assignments to enable full functionality. Each role serves different purposes in your workflow.
          </AlertDescription>
        </Alert>
      ) : (
        <Alert>
          <CheckCircle className="h-4 w-4" />
          <AlertDescription>
            All roles are assigned and ready to use! Your LLM configuration is complete.
          </AlertDescription>
        </Alert>
      )}

      {/* Role Assignment Cards */}
      {availableConfigs.length > 0 && (
        <div className="grid gap-6">
          {Object.entries(ROLE_DESCRIPTIONS).map(([key, role]) => {
            const IconComponent = role.icon;
            const currentAssignment = assignments[`${key}_llm_id` as keyof typeof assignments];
            const assignedConfig = availableConfigs.find(config => config.id === currentAssignment);
            
            return (
              <motion.div
                key={key}
                initial={{ opacity: 0, y: 10 }}
                animate={{ opacity: 1, y: 0 }}
                transition={{ delay: Object.keys(ROLE_DESCRIPTIONS).indexOf(key) * 0.1 }}
              >
                <Card className={`border-l-4 ${currentAssignment ? 'border-l-primary' : 'border-l-muted'} hover:shadow-md transition-shadow`}>
                  <CardHeader className="pb-3">
                    <div className="flex items-center justify-between">
                      <div className="flex items-center gap-3">
                        <div className={`p-2 rounded-lg ${role.color}`}>
                          <IconComponent className="w-5 h-5" />
                        </div>
                        <div>
                          <CardTitle className="text-lg">{role.title}</CardTitle>
                          <CardDescription className="mt-1">{role.description}</CardDescription>
                        </div>
                      </div>
                      {currentAssignment && (
                        <CheckCircle className="w-5 h-5 text-green-500" />
                      )}
                    </div>
                  </CardHeader>
                  <CardContent className="space-y-4">
                    <div className="space-y-2">
                      <div className="text-sm text-muted-foreground">
                        <strong>Use cases:</strong> {role.examples}
                      </div>
                      <div className="flex flex-wrap gap-1">
                        {role.characteristics.map((char, idx) => (
                          <Badge key={idx} variant="outline" className="text-xs">
                            {char}
                          </Badge>
                        ))}
                      </div>
                    </div>
                    
                    <div className="space-y-2">
                      <label className="text-sm font-medium">Assign LLM Configuration:</label>
                                             <Select
                         value={currentAssignment?.toString() || 'unassigned'}
                         onValueChange={(value) => handleRoleAssignment(`${key}_llm_id`, value)}
                       >
                        <SelectTrigger>
                          <SelectValue placeholder="Select an LLM configuration" />
                        </SelectTrigger>
                        <SelectContent>
                          <SelectItem value="unassigned">
                            <span className="text-muted-foreground">Unassigned</span>
                          </SelectItem>
                          {availableConfigs.map((config) => (
                            <SelectItem key={config.id} value={config.id.toString()}>
                              <div className="flex items-center gap-2">
                                <Badge variant="outline" className="text-xs">
                                  {config.provider}
                                </Badge>
                                <span>{config.name}</span>
                                <span className="text-muted-foreground">({config.model_name})</span>
                              </div>
                            </SelectItem>
                          ))}
                        </SelectContent>
                      </Select>
                    </div>

                    {assignedConfig && (
                      <div className="mt-3 p-3 bg-muted/50 rounded-lg">
                        <div className="flex items-center gap-2 text-sm">
                          <Bot className="w-4 h-4" />
                          <span className="font-medium">Assigned:</span>
                          <Badge variant="secondary">{assignedConfig.provider}</Badge>
                          <span>{assignedConfig.name}</span>
                        </div>
                        <div className="text-xs text-muted-foreground mt-1">
                          Model: {assignedConfig.model_name}
                        </div>
                        {assignedConfig.api_base && (
                          <div className="text-xs text-muted-foreground">
                            Base: {assignedConfig.api_base}
                          </div>
                        )}
                      </div>
                    )}
                  </CardContent>
                </Card>
              </motion.div>
            );
          })}
        </div>
      )}

      {/* Action Buttons */}
      {hasChanges && (
        <div className="flex justify-center gap-3 pt-4">
          <Button onClick={handleSave} disabled={isSaving} className="flex items-center gap-2">
            <Save className="w-4 h-4" />
            {isSaving ? 'Saving...' : 'Save Changes'}
          </Button>
          <Button variant="outline" onClick={handleReset} disabled={isSaving} className="flex items-center gap-2">
            <RotateCcw className="w-4 h-4" />
            Reset
          </Button>
        </div>
      )}

      {/* Status Indicator */}
      {isAssignmentComplete && !hasChanges && (
        <div className="flex justify-center pt-4">
          <div className="flex items-center gap-2 px-4 py-2 bg-green-50 text-green-700 rounded-lg border border-green-200">
            <CheckCircle className="w-4 h-4" />
            <span className="text-sm font-medium">All roles assigned and saved!</span>
          </div>
        </div>
      )}

      {/* Progress Indicator */}
      <div className="flex justify-center">
        <div className="flex items-center gap-2 text-sm text-muted-foreground">
          <span>Progress:</span>
          <div className="flex gap-1">
            {Object.keys(ROLE_DESCRIPTIONS).map((key, index) => (
              <div
                key={key}
                className={`w-2 h-2 rounded-full ${
                  assignments[`${key}_llm_id` as keyof typeof assignments]
                    ? 'bg-primary'
                    : 'bg-muted'
                }`}
              />
            ))}
          </div>
          <span>
            {assignedConfigIds.length} of {Object.keys(ROLE_DESCRIPTIONS).length} roles assigned
          </span>
        </div>
      </div>
        </div>
      )}
    </div>
  );
}