import { createError } from '@cirrusct/error';
import * as nodePath from 'path';
import * as ts from 'typescript';
import { createParsedConfig, createProgram, formatDiagnostics } from './lib';
import { ProgramOptions, TsConfig, TsProjectOptions } from './types';

const tsBuildInfoFile = './.tsbuildinfo';
const DefaultIncrementalBuild = true;

export class TsProject {
    private _parsedConfig: ts.ParsedCommandLine;
    private _compilerHost: ts.CompilerHost;
    private _builderProgram: ts.BuilderProgram;
    private _lastEmitResult: ts.EmitResult;

    constructor(public readonly projectOptions: TsProjectOptions) {}

    public get tsVersion(): string {
        return ts.version;
    }

    public get parsedConfig(): ts.ParsedCommandLine {
        if (!this._parsedConfig) {
            this._parsedConfig = createParsedConfig(this.projectOptions);
        }
        return this._parsedConfig;
    }

    // public get compilerHost(): ts.CompilerHost {
    //     if (!this._compilerHost) {
    //         this._compilerHost = ts.createCompilerHost(this.parsedConfig.options, true);
    //     }
    //     return this._compilerHost;
    // }

    public get compilerHost(): ts.CompilerHost {
        if (!this._compilerHost) {
            this._compilerHost = ts.createIncrementalCompilerHost(this.parsedConfig.options);
        }
        return this._compilerHost;
    }

    public get builderProgram(): ts.BuilderProgram {
        if (!this._builderProgram) {
            const buildInfoFilePath = nodePath.join(this.parsedConfig.options.outDir, tsBuildInfoFile);
            this._builderProgram = ts.createIncrementalProgram({
                rootNames: this.projectOptions.fileNames || this.parsedConfig.fileNames,
                host: this.compilerHost,
                options: {
                    ...(this.projectOptions.parsedCompilerOptions || this.parsedConfig.options),
                    incremental: this.projectOptions.incremental === false ? false : DefaultIncrementalBuild,
                    tsBuildInfoFile: buildInfoFilePath,
                },
            });
            // this._program = ts.createProgram(
            //     this.projectOptions.fileNames || this.parsedConfig.fileNames,
            //     this.projectOptions.parsedCompilerOptions || this.parsedConfig.options,
            //     this.compilerHost
            // );
        }
        return this._builderProgram;
    }

    public get program(): ts.Program {
        return this.builderProgram.getProgram();
    }

    public emit = (): ts.EmitResult => {
        this._lastEmitResult = this.program.emit();
        return this._lastEmitResult;
    };

    public getDiagnostics = (): ts.Diagnostic[] => {
        return ts
            .getPreEmitDiagnostics(this.program)
            .concat(this._lastEmitResult ? (this._lastEmitResult.diagnostics as any) : []); // tslint:disable-line: no-any
    };

    public getFormattedDiagnostics = (useColorAndContext: boolean = true): string => {
        return formatDiagnostics(this.getDiagnostics(), useColorAndContext);
    };
}