const core = require('@actions/core');
const github = require('@actions/github');
const axios = require('axios');
const detect = require('language-detect');
const httpsProxyAgent = require('https-proxy-agent');

function configWithProxy(config) {
    var c = config || {};
    if (process.env.OPENAI_PROXY) {
        core.debug(`use proxy: ${process.env.OPENAI_PROXY}`);
        c.proxy = false;
        c.httpsAgent = new httpsProxyAgent(process.env.OPENAI_PROXY);
        return c;
    }
    return c;
}



async function run() {
    try {
        // Get input values
        const programmingLanguage = core.getInput('PROGRAMMING_LANGUAGE');
        const openaiToken = core.getInput('OPENAI_TOKEN');
        const fullReviewComment = core.getInput('FULL_REVIEW_COMMENT');
        const reviewCommentPrefix = core.getInput('REVIEW_COMMENT_PREFIX');
        const githubToken = core.getInput('GITHUB_TOKEN');
        const githubBaseURL = core.getInput('GITHUB_BASE_URL') || process.env.GITHUB_API_URL;
        const promptTemplate = core.getInput('PROMPT_TEMPLATE');
        const maxCodeLength = core.getInput('MAX_CODE_LENGTH');
        const answerTemplate = core.getInput('ANSWER_TEMPLATE');
        const giteaToken = core.getInput('GITHUB_TOKEN');
        const sourceAt = core.getInput('SOURCE_AT');

        core.debug(`programmingLanguage: ${programmingLanguage}`);
        core.debug(`openaiToken length: ${openaiToken.length}`);
        core.debug(`fullReviewComment: ${fullReviewComment}`);
        core.debug(`reviewCommentPrefix: ${reviewCommentPrefix}`);
        core.debug(`githubToken length: ${githubToken.length}`);
        core.debug(`githubBaseURL: ${githubBaseURL}`);
        core.debug(`promptTemplate: ${promptTemplate}`);
        core.debug(`maxCodeLength: ${maxCodeLength}`);
        core.debug(`answerTemplate: ${answerTemplate}`);
        core.debug(`SourceAt: ${sourceAt}`);

        // Get information about the pull request review
        const comment = github.context.payload.comment;
        const repoName = github.context.payload.repository.name;
        const repoOwner = github.context.payload.repository.owner.login;
        const prNumber = github.context.payload.number || github.context.payload.issue.number; // get number from a pull request event or comment event

        // Get the code to analyze from the review comment
        var content = comment && comment.body || '';

        if(sourceAt === 'github') {

            const url = `${githubBaseURL}/repos/${repoOwner}/${repoName}/pulls/${prNumber}`;
            console.log(`diff url: ${url}`);
            var response = await axios.get(url, {
                headers: {
                    Authorization: `token ${githubToken}`,
                    Accept: 'application/vnd.github.diff'
                }
            });
            const code = response.data;
            core.debug(`diff code: ${code}`);
            const files = parsePullRequestDiff(code);
            core.debug(`diff files: ${files}`);

            if (!content || content == fullReviewComment) {
                // Extract the code from the pull request content
                content = promptTemplate.replace('${code}', code);
            } else {
                content = content.substring(reviewCommentPrefix.length);
                content = content.replace('${code}', code);
                const fileNames = findFileNames(content);
                core.debug(`found files name in commment: ${fileNames}`);
                for (const fileName of fileNames) {
                    for (const key of Object.keys(files)) {
                        if (key.includes(fileName)) {
                            core.debug(`replace \${file:${fileName}} with ${key}'s diff`);
                            content = content.replace(`\${file:${fileName}}`, files[key]);
                            break;
                        }
                    }
                }
            }
            content = content.substring(0, maxCodeLength);
        }
        else if(sourceAt === 'gitea')
        {
            const url = `${githubBaseURL}/api/v1/repos/${repoOwner}/${repoName}/pulls/${prNumber}.diff`;
            console.log(`diff url: ${url}`);
            var response = await axios.get(url, {
                headers: {
                    Authorization: `token ${githubToken}`,
                    Accept: 'application/vnd.github.diff'
                }
            });
            const code = response.data;
            core.debug(`diff code: ${code}`);
            const files = parsePullRequestDiff(code);
            core.debug(`diff files: ${files}`);

            if (!content || content == fullReviewComment) {
                // Extract the code from the pull request content
                content = promptTemplate.replace('${code}', code);
            } else {
                content = content.substring(reviewCommentPrefix.length);
                content = content.replace('${code}', code);
                const fileNames = findFileNames(content);
                core.debug(`found files name in commment: ${fileNames}`);
                for (const fileName of fileNames) {
                    for (const key of Object.keys(files)) {
                        if (key.includes(fileName)) {
                            core.debug(`replace \${file:${fileName}} with ${key}'s diff`);
                            content = content.replace(`\${file:${fileName}}`, files[key]);
                            break;
                        }
                    }
                }
            }
            content = content.substring(0, maxCodeLength);
        }
        // Determine the programming language if it was not provided
        if (programmingLanguage == 'auto') {
            const detectedLanguage = detect(code);
            core.debug(`Detected programming language: ${detectedLanguage}`);
            programmingLanguage = detectedLanguage;
        }

        var messages = [{
            role: "system",
            content: `You are a master of programming language ${programmingLanguage}`
        }, {
            role: "user",
            content: content
        }];

        core.debug(`content: ${content}`);

        // Call the OpenAI ChatGPT API to analyze the code
        response = await axios.post('https://api.openai.com/v1/chat/completions', {
            "model": "gpt-3.5-turbo",
            "messages": messages
        }, configWithProxy({
            headers: {
                'Content-Type': 'application/json',
                'Authorization': `Bearer ${openaiToken}`
            }
        }));

        const answer = response.data.choices[0].message.content;
        core.debug(`openai response: ${answer}`);

        if(sourceAt === 'github') {
            // Reply to the review comment with the OpenAI response
            const octokit = new github.getOctokit(githubToken, {
                baseUrl: githubBaseURL
            });

            await octokit.rest.issues.createComment({
                owner: repoOwner,
                repo: repoName,
                issue_number: prNumber,
                body: answerTemplate.replace('${answer}', answer)

            });
        } else if (sourceAt === 'gitea')
        {


            // Make a POST request to create a comment on a pull request
            const comment = answerTemplate.replace('${answer}', answer);
            const url = `${githubBaseURL}/api/v1/repos/${repoOwner}/${repoName}/issues/${prNumber}/comments`;
            const headers = { 'Content-Type': 'application/json', 'Authorization': `token ${githubToken}` };
            const data = { 'body': `${comment}`};
            core.debug(`url: ${url}`);
            core.debug(`githubToken: ${githubToken}`);
            core.debug(`data.body: ${data.body}`);
            var response = await axios.post(url, data, {
                headers: {
                    Authorization: `token ${githubToken}`,
                    Accept: 'application/json'
                }
            });
        }
    } catch (error) {
        core.setFailed(error.message);
    }
}

function parsePullRequestDiff(diffContent) {
    const files = {};
    const diffLines = diffContent.split('\n');

    let currentFile = null;
    let currentLines = [];

    for (const line of diffLines) {
        if (line.startsWith('diff --git')) {
            // Start of a new file
            if (currentFile) {
                files[currentFile] = currentLines.join('\n');
            }
            currentFile = line.substring('diff --git'.length + 1);
            currentLines = [line];
        } else {
            // Add the line to the current file's diff
            currentLines.push(line);
        }
    }

    // Add the last file's diff
    if (currentFile) {
        files[currentFile] = currentLines.join('\n');
    }

    return files;
}

function findFileNames(str) {
    const pattern = /\${file:([^{}]+)}/g;
    const matches = str.matchAll(pattern);
    const names = [];
    for (const match of matches) {
        names.push(match[1]);
    }
    return names;
}

run();