/**
 * Usage Analytics Data Store
 *
 * Manages AI usage analytics and performance metrics
 *
 * @package ThinkRank
 * @since 1.0.0
 */

import { createReduxStore } from '@wordpress/data';
import apiFetch from '@wordpress/api-fetch';

// Initial state
const DEFAULT_STATE = {
    metrics: {},
    reports: {},
    costs: {},
    usage: {},
    isLoading: false,
    error: null,
    lastUpdated: null,
};

// Action types
const TYPES = {
    SET_METRICS: 'SET_METRICS',
    SET_REPORTS: 'SET_REPORTS',
    SET_COSTS: 'SET_COSTS',
    SET_USAGE: 'SET_USAGE',
    SET_LOADING: 'SET_LOADING',
    SET_ERROR: 'SET_ERROR',
    SET_LAST_UPDATED: 'SET_LAST_UPDATED',
    CLEAR_ERROR: 'CLEAR_ERROR',
};

// Reducer
const reducer = (state = DEFAULT_STATE, action) => {
    switch (action.type) {
        case TYPES.SET_METRICS:
            return {
                ...state,
                metrics: action.metrics,
                error: null, // Clear error on successful data fetch
            };

        case TYPES.SET_REPORTS:
            return {
                ...state,
                reports: action.reports,
                error: null,
            };

        case TYPES.SET_COSTS:
            return {
                ...state,
                costs: action.costs,
                error: null,
            };

        case TYPES.SET_USAGE:
            return {
                ...state,
                usage: action.usage,
                error: null,
            };

        case TYPES.SET_LOADING:
            return {
                ...state,
                isLoading: action.loading,
            };

        case TYPES.SET_ERROR:
            return {
                ...state,
                error: action.error,
                isLoading: false, // Stop loading on error
            };

        case TYPES.CLEAR_ERROR:
            return {
                ...state,
                error: null,
            };

        case TYPES.SET_LAST_UPDATED:
            return {
                ...state,
                lastUpdated: action.timestamp,
            };

        default:
            return state;
    }
};

// Actions
const actions = {
    setMetrics(metrics) {
        return {
            type: TYPES.SET_METRICS,
            metrics,
        };
    },

    setReports(reports) {
        return {
            type: TYPES.SET_REPORTS,
            reports,
        };
    },

    setCosts(costs) {
        return {
            type: TYPES.SET_COSTS,
            costs,
        };
    },

    setUsage(usage) {
        return {
            type: TYPES.SET_USAGE,
            usage,
        };
    },

    setLoading(loading) {
        return {
            type: TYPES.SET_LOADING,
            loading,
        };
    },

    setError(error) {
        return {
            type: TYPES.SET_ERROR,
            error,
        };
    },

    clearError() {
        return {
            type: TYPES.CLEAR_ERROR,
        };
    },

    setLastUpdated(timestamp) {
        return {
            type: TYPES.SET_LAST_UPDATED,
            timestamp,
        };
    },

    // Simple action that returns a function for async operations
    fetchMetrics: (period = '30d', userId = 0) => {
        return async ({ dispatch }) => {
            dispatch(actions.setLoading(true));
            dispatch(actions.clearError());

            try {
                const response = await apiFetch({
                    path: `/thinkrank/v1/analytics/overview?period=${period}&user_id=${userId}`,
                });

                if (response && response.success && response.data) {
                    dispatch(actions.setMetrics(response.data));
                    dispatch(actions.setLastUpdated(Date.now()));
                } else {
                    throw new Error(response?.message || 'Failed to fetch analytics data');
                }

            } catch (error) {
                console.error('Failed to fetch analytics metrics:', error);

                let errorMessage = 'Failed to load analytics data';
                if (error.message) {
                    if (error.message.includes('404')) {
                        errorMessage = 'Analytics API endpoint not found.';
                    } else if (error.message.includes('403')) {
                        errorMessage = 'You do not have permission to view analytics data.';
                    } else if (error.message.includes('500')) {
                        errorMessage = 'Server error while loading analytics data.';
                    } else {
                        errorMessage = error.message;
                    }
                }

                dispatch(actions.setError({
                    message: errorMessage,
                    code: error.code || 'fetch_error',
                    type: 'metrics'
                }));
            } finally {
                dispatch(actions.setLoading(false));
            }
        };
    },

    fetchUsageBreakdown: (period = '30d', groupBy = 'day', userId = 0) => {
        return async ({ dispatch }) => {
            dispatch(actions.setLoading(true));
            dispatch(actions.clearError());

            try {
                const response = await apiFetch({
                    path: `/thinkrank/v1/analytics/usage?period=${period}&group_by=${groupBy}&user_id=${userId}`,
                });

                if (response && response.success && response.data) {
                    dispatch(actions.setUsage(response.data));
                } else {
                    throw new Error(response?.message || 'Failed to fetch usage data');
                }

            } catch (error) {
                console.error('Failed to fetch usage breakdown:', error);
                dispatch(actions.setError({
                    message: error.message || 'Failed to load usage data',
                    code: error.code || 'fetch_error',
                    type: 'usage'
                }));
            } finally {
                dispatch(actions.setLoading(false));
            }
        };
    },

    fetchCostAnalysis: (period = '30d', provider = 'all', userId = 0) => {
        return async ({ dispatch }) => {
            dispatch(actions.setLoading(true));
            dispatch(actions.clearError());

            try {
                const response = await apiFetch({
                    path: `/thinkrank/v1/analytics/costs?period=${period}&provider=${provider}&user_id=${userId}`,
                });

                if (response && response.success && response.data) {
                    dispatch(actions.setCosts(response.data));
                } else {
                    throw new Error(response?.message || 'Failed to fetch cost data');
                }

            } catch (error) {
                console.error('Failed to fetch cost analysis:', error);
                dispatch(actions.setError({
                    message: error.message || 'Failed to load cost data',
                    code: error.code || 'fetch_error',
                    type: 'costs'
                }));
            } finally {
                dispatch(actions.setLoading(false));
            }
        };
    },

    fetchReports: (type = 'overview') => {
        return async ({ dispatch }) => {
            dispatch(actions.setLoading(true));
            dispatch(actions.clearError());

            try {
                // Placeholder for future reports implementation
                const reports = {
                    type,
                    message: 'Reports feature coming in Phase 4'
                };

                dispatch(actions.setReports(reports));

            } catch (error) {
                console.error('Failed to fetch reports:', error);
                dispatch(actions.setError({
                    message: error.message || 'Failed to load reports',
                    code: error.code || 'fetch_error',
                    type: 'reports'
                }));
            } finally {
                dispatch(actions.setLoading(false));
            }
        };
    },
};

// Selectors
const selectors = {
    // Basic state selectors
    getMetrics(state) {
        return state.metrics;
    },

    getReports(state) {
        return state.reports;
    },

    getCosts(state) {
        return state.costs;
    },

    getUsage(state) {
        return state.usage;
    },

    getIsLoading(state) {
        return state.isLoading;
    },

    getError(state) {
        return state.error;
    },

    getLastUpdated(state) {
        return state.lastUpdated;
    },

    // Metrics selectors
    getContentOptimized(state) {
        return state.metrics.content_optimized || 0;
    },

    getAverageSeoScore(state) {
        return state.metrics.average_seo_score || 0;
    },

    getCreditsUsed(state) {
        return state.metrics.credits_used || 0;
    },

    getTimeSaved(state) {
        return state.metrics.time_saved || 0;
    },

    getAiActions(state) {
        return state.metrics.ai_actions || 0;
    },

    getContentBriefs(state) {
        return state.metrics.content_briefs || 0;
    },

    getFeaturesUsedCount(state) {
        return state.metrics.features_used_count || 0;
    },

    getMostUsedFeature(state) {
        return state.metrics.most_used_feature || '';
    },

    getMostUsedCount(state) {
        return state.metrics.most_used_count || 0;
    },

    getSuccessRate(state) {
        return state.metrics.success_rate || 0;
    },

    getFeatureBreakdown(state) {
        return state.metrics.feature_breakdown || {};
    },

    getProviderBreakdown(state) {
        return state.metrics.provider_breakdown || {};
    },

    // Cost-related selectors
    getTotalCosts(state) {
        return state.metrics.total_cost || 0;
    },

    getCostsByProvider(state) {
        const breakdown = state.metrics.provider_breakdown || {};
        return {
            openai: breakdown.openai?.cost || 0,
            claude: breakdown.claude?.cost || 0
        };
    },

    getEstimatedMonthlyCost(state) {
        const totalCost = state.metrics.total_cost || 0;
        const period = state.metrics.period || '30d';

        // Calculate monthly projection based on current period
        switch (period) {
            case '7d':
                return totalCost * (30 / 7);
            case '30d':
                return totalCost;
            case '90d':
                return totalCost / 3;
            default:
                return totalCost;
        }
    },

    getCostEfficiency(state) {
        const totalCost = state.metrics.total_cost || 0;
        const contentOptimized = state.metrics.content_optimized || 0;
        const avgScore = state.metrics.average_seo_score || 0;

        return {
            costPerOptimizedPost: contentOptimized > 0 ? totalCost / contentOptimized : 0,
            costPerSeoPoint: avgScore > 0 ? totalCost / avgScore : 0,
            timeSavedValue: (state.metrics.time_saved || 0) * 0.5 // Assuming $30/hour, 0.5 per minute
        };
    },

    // Usage trend selectors
    getUsageTrend(state) {
        return state.usage.trend || [];
    },

    getFeatureUsageBreakdown(state) {
        return state.usage.by_feature || {};
    },

    // Error handling selectors
    hasError(state) {
        return !!state.error;
    },

    getErrorMessage(state) {
        return state.error?.message || '';
    },

    getErrorType(state) {
        return state.error?.type || '';
    },

    // Data availability selectors
    hasData(state) {
        const metrics = state.metrics;
        return !!(metrics.content_optimized || metrics.ai_actions || metrics.total_cost);
    },

    isDataStale(state) {
        if (!state.lastUpdated) return true;
        const fiveMinutes = 5 * 60 * 1000;
        return Date.now() - state.lastUpdated > fiveMinutes;
    },

    // Combined selectors for dashboard cards (8-card layout)
    getDashboardMetrics(state) {
        // Format most used feature display
        const mostUsedFeature = state.metrics.most_used_feature || '';
        const mostUsedCount = state.metrics.most_used_count || 0;

        // Get contextual subtitle based on feature type
        const getFeatureSubtitle = (feature, count) => {
            if (!feature || count === 0) return '';

            // Map feature types to their action descriptions
            const actionMap = {
                'content_brief': 'Generated',
                'seo_metadata': 'Optimized',
                'content_analysis': 'Analyzed',
                'site_identity_optimization': 'Optimized',
                'homepage_meta_optimization': 'Optimized',
                'homepage_hero_optimization': 'Optimized',
                'llms_txt_optimization': 'Generated'
            };

            const action = actionMap[feature] || 'Used';
            return `${count} ${action}`;
        };

        const mostUsedDisplay = mostUsedFeature ?
            mostUsedFeature.replace(/_/g, ' ').replace(/\b\w/g, l => l.toUpperCase()).replace(/\bSeo\b/g, 'SEO') :
            'None';
        const mostUsedSubtitle = getFeatureSubtitle(mostUsedFeature, mostUsedCount);

        return {
            // Row 1: Core Performance Metrics
            postsAnalyzed: {
                value: state.metrics.content_optimized || 0,
                change: state.metrics.content_optimized_change || 0,
                label: 'Posts Analyzed'
            },
            aiOptimizations: {
                value: state.metrics.ai_actions || 0,
                change: 0, // No change tracking for total actions yet
                label: 'AI Optimizations'
            },
            averageSeoScore: {
                value: state.metrics.average_seo_score || 0,
                change: state.metrics.seo_score_change || 0,
                label: 'Average SEO Score',
                suffix: '/100'
            },
            totalCost: {
                value: state.metrics.total_cost || 0,
                change: state.metrics.cost_change || 0,
                label: 'AI Credits Used',
                prefix: '$',
                subtitle: `${state.metrics.total_tokens || 0} tokens`
            },
            // Row 2: Feature & Efficiency Metrics
            featuresUsed: {
                value: state.metrics.features_used_count || 0,
                change: 0, // No change tracking for features count yet
                label: 'Features Used'
            },
            timeSaved: {
                value: Math.round((state.metrics.time_saved || 0) / 60),
                change: state.metrics.time_saved_change || 0,
                label: 'Time Saved',
                suffix: 'h',
                subtitle: `${state.metrics.ai_actions || 0} AI actions`
            },
            mostUsedFeature: {
                value: mostUsedDisplay,
                change: 0, // No change tracking for most used feature yet
                label: 'Most Used Feature',
                subtitle: mostUsedSubtitle,
                isText: true
            },
            successRate: {
                value: state.metrics.success_rate || 0,
                change: 0, // No change tracking for success rate yet
                label: 'Success Rate',
                suffix: '%'
            }
        };
    },
};

// Create and export store
const store = createReduxStore('thinkrank/analytics', {
    reducer,
    actions,
    selectors,
});

export default store;