/*
 * Copyright 2025 Google LLC
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import * as fs from 'fs';
import * as path from 'path';
import yargs from 'yargs';
import {hideBin} from 'yargs/helpers';
import {logger, setupLogger} from './logger';
import {modelsToTest} from './models';
import {prompts, TestPrompt} from './prompts';
import {Generator} from './generator';
import {Validator} from './validator';
import {Evaluator} from './evaluator';
import {EvaluatedResult} from './types';
import {analysisFlow} from './analysis_flow';

const schemaFiles = [
  '../../json/common_types.json',
  '../../catalogs/basic/catalog.json',
  '../../json/server_to_client.json',
];

function loadSchemas(): Record<string, any> {
  const schemas: Record<string, any> = {};
  for (const file of schemaFiles) {
    const schemaString = fs.readFileSync(path.join(__dirname, file), 'utf-8');
    const schema = JSON.parse(schemaString);
    const key = file.replace('../../', '');
    schemas[key] = schema;
  }

  // Alias catalogs/basic/catalog.json to catalog.json to match server_to_client.json references
  // This mirrors the logic in run_tests.py
  if (schemas['catalogs/basic/catalog.json']) {
    const catalogSchema = JSON.parse(JSON.stringify(schemas['catalogs/basic/catalog.json']));
    if (catalogSchema['$id']) {
      catalogSchema['$id'] = catalogSchema['$id'].replace(
        /catalogs\/basic\/catalog\.json$/,
        'catalog.json',
      );
    }
    schemas['catalog.json'] = catalogSchema;
  }

  return schemas;
}

function generateSummary(
  results: EvaluatedResult[],
  analysisResults: Record<string, string>,
): string {
  const promptNameWidth = 40;
  const latencyWidth = 20;
  const failedRunsWidth = 15;
  const severityWidth = 15;

  // Group by model
  const resultsByModel: Record<string, EvaluatedResult[]> = {};
  for (const result of results) {
    if (!resultsByModel[result.modelName]) {
      resultsByModel[result.modelName] = [];
    }
    resultsByModel[result.modelName].push(result);
  }

  let summary = '# Evaluation Summary';
  for (const modelName in resultsByModel) {
    summary += `\n\n## Model: ${modelName}\n\n`;
    const header = `| ${'Prompt Name'.padEnd(
      promptNameWidth,
    )} | ${'Avg Latency (ms)'.padEnd(latencyWidth)} | ${'Schema Fail'.padEnd(
      failedRunsWidth,
    )} | ${'Eval Fail'.padEnd(failedRunsWidth)} | ${'Minor'.padEnd(
      severityWidth,
    )} | ${'Significant'.padEnd(severityWidth)} | ${'Critical'.padEnd(severityWidth)} |`;
    const divider = `|${'-'.repeat(promptNameWidth + 2)}|${'-'.repeat(
      latencyWidth + 2,
    )}|${'-'.repeat(failedRunsWidth + 2)}|${'-'.repeat(
      failedRunsWidth + 2,
    )}|${'-'.repeat(severityWidth + 2)}|${'-'.repeat(
      severityWidth + 2,
    )}|${'-'.repeat(severityWidth + 2)}|`;
    summary += header;
    summary += `\n${divider}`;

    const modelResults = resultsByModel[modelName];
    const promptsInModel = modelResults.reduce(
      (acc, result) => {
        if (!acc[result.prompt.name]) {
          acc[result.prompt.name] = [];
        }
        acc[result.prompt.name].push(result);
        return acc;
      },
      {} as Record<string, EvaluatedResult[]>,
    );

    const sortedPromptNames = Object.keys(promptsInModel).sort();
    for (const promptName of sortedPromptNames) {
      const runs = promptsInModel[promptName];
      const totalRuns = runs.length;
      const schemaFailedRuns = runs.filter(r => r.error || r.validationErrors.length > 0).length;
      const evalFailedRuns = runs.filter(
        r => r.evaluationResult && !r.evaluationResult.pass,
      ).length;

      const totalLatency = runs.reduce((acc, r) => acc + r.latency, 0);
      const avgLatency = (totalLatency / totalRuns).toFixed(0);

      const schemaFailedStr = schemaFailedRuns > 0 ? `${schemaFailedRuns} / ${totalRuns}` : '';
      const evalFailedStr = evalFailedRuns > 0 ? `${evalFailedRuns} / ${totalRuns}` : '';

      let minorCount = 0;
      let significantCount = 0;
      let criticalCount = 0;

      for (const r of runs) {
        if (r.evaluationResult?.issues) {
          for (const issue of r.evaluationResult.issues) {
            if (issue.severity === 'minor') minorCount++;
            else if (issue.severity === 'significant') significantCount++;
            else if (issue.severity === 'critical') criticalCount++;
          }
        }
      }

      const minorStr = minorCount > 0 ? `${minorCount}` : '';
      const significantStr = significantCount > 0 ? `${significantCount}` : '';
      const criticalStr = criticalCount > 0 ? `${criticalCount}` : '';

      summary += `\n| ${promptName.padEnd(
        promptNameWidth,
      )} | ${avgLatency.padEnd(latencyWidth)} | ${schemaFailedStr.padEnd(
        failedRunsWidth,
      )} | ${evalFailedStr.padEnd(failedRunsWidth)} | ${minorStr.padEnd(
        severityWidth,
      )} | ${significantStr.padEnd(severityWidth)} | ${criticalStr.padEnd(severityWidth)} |`;
    }

    const totalRunsForModel = modelResults.length;
    const successfulRuns = modelResults.filter(
      r =>
        !r.error &&
        r.validationErrors.length === 0 &&
        (!r.evaluationResult || r.evaluationResult.pass),
    ).length;

    const schemaSuccessfulRuns = modelResults.filter(
      r => !r.error && r.validationErrors.length === 0,
    ).length;

    const schemaSuccessPercentage =
      totalRunsForModel === 0
        ? '0.0'
        : ((schemaSuccessfulRuns / totalRunsForModel) * 100.0).toFixed(1);

    const successPercentage =
      totalRunsForModel === 0 ? '0.0' : ((successfulRuns / totalRunsForModel) * 100.0).toFixed(1);

    summary += `\n\n**Schema successful runs:** ${schemaSuccessfulRuns} / ${totalRunsForModel} (${schemaSuccessPercentage}% schema success)`;
    summary += `\n**Total successful eval runs:** ${successfulRuns} / ${totalRunsForModel} (${successPercentage}% overall success)`;

    if (analysisResults[modelName]) {
      summary += `\n\n### Failure Analysis\n\n${analysisResults[modelName]}`;
    }
  }

  summary += '\n\n---\n\n## Overall Summary\n';
  const totalRuns = results.length;
  const totalToolErrorRuns = results.filter(r => r.error).length;
  const totalRunsWithAnyFailure = results.filter(
    r =>
      r.error || r.validationErrors.length > 0 || (r.evaluationResult && !r.evaluationResult.pass),
  ).length;

  const modelsWithFailures = [
    ...new Set(
      results
        .filter(
          r =>
            r.error ||
            r.validationErrors.length > 0 ||
            (r.evaluationResult && !r.evaluationResult.pass),
        )
        .map(r => r.modelName),
    ),
  ].join(', ');

  let totalMinor = 0;
  let totalSignificant = 0;
  let totalCritical = 0;
  let totalCriticalSchema = 0;

  for (const r of results) {
    if (r.evaluationResult?.issues) {
      for (const issue of r.evaluationResult.issues) {
        if (issue.severity === 'minor') totalMinor++;
        else if (issue.severity === 'significant') totalSignificant++;
        else if (issue.severity === 'critical') totalCritical++;
        else if (issue.severity === 'criticalSchema') totalCriticalSchema++;
      }
    }
  }

  summary += `\n- **Total tool failures:** ${totalToolErrorRuns} / ${totalRuns}`;
  const successPercentage =
    totalRuns === 0
      ? '0.0'
      : (((totalRuns - totalRunsWithAnyFailure) / totalRuns) * 100.0).toFixed(1);
  summary += `\n- **Number of runs with any failure (tool error, validation, or eval):** ${totalRunsWithAnyFailure} / ${totalRuns} (${successPercentage}% success)`;
  summary += `\n- **Severity Breakdown:**`;
  summary += `\n  - **Minor:** ${totalMinor}`;
  summary += `\n  - **Significant:** ${totalSignificant}`;
  summary += `\n  - **Critical (Eval):** ${totalCritical}`;
  summary += `\n  - **Critical (Schema):** ${totalCriticalSchema}`;

  const latencies = results.map(r => r.latency).sort((a, b) => a - b);
  const totalLatency = latencies.reduce((acc, l) => acc + l, 0);
  const meanLatency = totalRuns > 0 ? (totalLatency / totalRuns).toFixed(0) : '0';
  let medianLatency = 0;
  if (latencies.length > 0) {
    const mid = Math.floor(latencies.length / 2);
    if (latencies.length % 2 === 0) {
      medianLatency = (latencies[mid - 1] + latencies[mid]) / 2;
    } else {
      medianLatency = latencies[mid];
    }
  }

  summary += `\n- **Mean Latency:** ${meanLatency} ms`;
  summary += `\n- **Median Latency:** ${medianLatency} ms`;

  if (modelsWithFailures) {
    summary += `\n- **Models with at least one failure:** ${modelsWithFailures}`;
  }
  return summary;
}

async function main() {
  const argv = await yargs(hideBin(process.argv))
    .option('log-level', {
      type: 'string',
      description: 'Set the logging level',
      default: 'info',
      choices: ['debug', 'info', 'warn', 'error'],
    })
    .option('results', {
      type: 'string',
      description:
        'Directory to keep output files. If not specified, uses results/output-<model>. If specified, uses the provided directory (appending output-<model>).',
      coerce: arg => (arg === undefined ? true : arg),
      default: true,
    })
    .option('runs-per-prompt', {
      type: 'number',
      description: 'Number of times to run each prompt',
      default: 1,
    })
    .option('model', {
      type: 'string',
      array: true,
      description: 'Filter models by exact name',
      default: [],
      choices: modelsToTest.map(m => m.name),
    })
    .option('prompt', {
      type: 'string',
      array: true,
      description: 'Filter prompts by name prefix',
    })
    .option('eval-model', {
      type: 'string',
      description: 'Model to use for evaluation',
      default: 'gemini-2.5-flash',
      choices: modelsToTest.map(m => m.name),
    })
    .option('clean-results', {
      type: 'boolean',
      description: 'Clear the output directory before starting',
      default: false,
    })

    .help()
    .alias('h', 'help')
    .strict().argv;

  // Filter Models
  let filteredModels = modelsToTest;
  if (argv.model && argv.model.length > 0) {
    const modelNames = argv.model as string[];
    filteredModels = modelsToTest.filter(m => modelNames.includes(m.name));
    if (filteredModels.length === 0) {
      logger.error(`No models found matching: ${modelNames.join(', ')}.`);
      process.exit(1);
    }
  }

  // Filter Prompts
  let filteredPrompts = prompts;
  if (argv.prompt && argv.prompt.length > 0) {
    const promptPrefixes = argv.prompt as string[];
    filteredPrompts = prompts.filter(p => promptPrefixes.some(prefix => p.name.startsWith(prefix)));
    if (filteredPrompts.length === 0) {
      logger.error(`No prompt found with prefix "${promptPrefixes.join(', ')}".`);
      process.exit(1);
    }
  }

  // Determine Output Directory (Base)
  // Note: Generator/Validator/Evaluator handle per-model subdirectories if outputDir is provided.
  // But we need a base output dir to pass to them.
  let resultsBaseDir: string | undefined;
  const resultsArg = argv.results;
  if (typeof resultsArg === 'string') {
    resultsBaseDir = resultsArg;
  } else if (resultsArg === true) {
    resultsBaseDir = 'results';
  }

  // Clean Results
  if (argv['clean-results'] && resultsBaseDir && fs.existsSync(resultsBaseDir)) {
    // Only force clean known result directories for safety if the user provides the flag.
    if (resultsBaseDir === 'results') {
      fs.rmSync(resultsBaseDir, {recursive: true, force: true});
    } else {
      fs.rmSync(resultsBaseDir, {recursive: true, force: true});
    }
  }

  // Configure global logger. File logging is currently only supported when testing a single model.
  if (resultsBaseDir) {
    if (filteredModels.length === 1) {
      const modelDirName = `output-${filteredModels[0].name.replace(/[\/:]/g, '_')}`;
      setupLogger(path.join(resultsBaseDir, modelDirName), argv['log-level']);
    } else {
      setupLogger(undefined, argv['log-level']);
    }
  } else {
    setupLogger(undefined, argv['log-level']);
  }

  const schemas = loadSchemas();
  const catalogRulesPath = path.join(__dirname, '../../json/basic_catalog_rules.txt');
  let catalogRules: string | undefined;
  if (fs.existsSync(catalogRulesPath)) {
    catalogRules = fs.readFileSync(catalogRulesPath, 'utf-8');
  } else {
    logger.warn(
      `Catalog rules file not found at ${catalogRulesPath}. Proceeding without specific catalog rules.`,
    );
  }

  // Phase 1: Generation
  const generator = new Generator(schemas, resultsBaseDir, catalogRules);
  const generatedResults = await generator.run(
    filteredPrompts,
    filteredModels,
    argv['runs-per-prompt'],
  );

  // Phase 2: Validation
  const validator = new Validator(schemas, resultsBaseDir);
  const validatedResults = await validator.run(generatedResults);

  // Phase 3: Evaluation
  const evaluator = new Evaluator(schemas, argv['eval-model'], resultsBaseDir);
  const evaluatedResults = await evaluator.run(validatedResults);

  // Phase 4: Failure Analysis
  const analysisResults: Record<string, string> = {};
  const resultsByModel: Record<string, EvaluatedResult[]> = {};
  for (const result of evaluatedResults) {
    if (!resultsByModel[result.modelName]) {
      resultsByModel[result.modelName] = [];
    }
    resultsByModel[result.modelName].push(result);
  }

  for (const modelName in resultsByModel) {
    const modelResults = resultsByModel[modelName];
    const failures = modelResults
      .filter(
        r =>
          r.error ||
          r.validationErrors.length > 0 ||
          (r.evaluationResult && !r.evaluationResult.pass),
      )
      .map(r => {
        let failureType = 'Unknown';
        let reason = 'Unknown';
        let issues: string[] = [];

        if (r.error) {
          failureType = 'Tool Error';
          reason = r.error.message || String(r.error);
        } else if (r.validationErrors.length > 0) {
          failureType = 'Schema Validation';
          reason = 'Schema validation failed';
          issues = r.validationErrors;
        } else if (r.evaluationResult && !r.evaluationResult.pass) {
          failureType = 'Evaluation Failure';
          reason = r.evaluationResult.reason;
          if (r.evaluationResult.issues) {
            issues = r.evaluationResult.issues.map(i => `${i.severity}: ${i.issue}`);
          }
        }

        return {
          promptName: r.prompt.name,
          runNumber: r.runNumber,
          failureType,
          reason,
          issues,
        };
      });

    if (failures.length > 0) {
      logger.info(`Running failure analysis for model: ${modelName}...`);
      try {
        const analysis = await analysisFlow({
          modelName,
          failures,
          numRuns: modelResults.length,
          evalModel: argv['eval-model'],
        });
        analysisResults[modelName] = analysis;
      } catch (e) {
        logger.error(`Failed to run failure analysis for ${modelName}: ${e}`);
        analysisResults[modelName] = 'Failed to run analysis.';
      }
    }
  }

  // Summary
  const summary = generateSummary(evaluatedResults, analysisResults);
  logger.info(summary);

  if (resultsBaseDir) {
    // Save a copy of the evaluation summary to each model's output directory.
    for (const model of filteredModels) {
      const modelDirName = `output-${model.name.replace(/[\/:]/g, '_')}`;
      const modelDir = path.join(resultsBaseDir, modelDirName);
      if (fs.existsSync(modelDir)) {
        fs.writeFileSync(path.join(modelDir, 'summary.md'), summary);
      }
    }
  }
}

if (require.main === module) {
  main().catch(console.error);
}
